The Epistemology of Keith Lehrer (Philosophical Studies Series)

THE EPISTEMOLOGY OF KEITH LEHRER

PHILOSOPHICAL STUDIES SERIES VOLUME 95

Founded by Wilfrid S. Sellars and Keith Lehrer

Editor Keith Lehrer, University of Arizona, Tucson Associate Editor Stewart Cohen, Arizona State University, Tempe Board of Consulting Editors Lynne Rudder Baker, University of Massachusetts at Amherst Radu Bogdan, Tulane University, New Orleans Marian David, University of Notre Dame Allan Gibbard, University of Michigan Denise Meyerson, Macquarie University François Recanati, Institut Jean-Nicod, EHESS, Paris Stuart Silvers, Clemson University Barry Smith, State University of New York at Buffalo Nicholas D. Smith, Lewis & Clark College

The titles published in this series are listed at the end of this volume.

THE EPISTEMOLOGY OF KEITH LEHRER Edited by

ERIK J. OLSSON University of Constance, Germany

KLUWER ACADEMIC PUBLISHERS DORDRECHT / BOSTON / LONDON

A C.I.P. Catalogue record for this book is available from the Library of Congress.

ISBN 1-4020-1605-0

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Cover art: MetaMe, Keith Lehrer, 2002, Oil painting, 16˝ × 20˝

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Table of Contents PREF ACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

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INTRODUCTION ............................................ . Erik J. Olsson: "The Epistemology of Keith Lehrer"

EXTERNALISMVS. INTERNALISM ............................ 21 Chapter 1, Ernest Sosa: "Epistemology: Does it Depend on Independence?" . . . . . . .. 23 Chapter 2 John Greco: "Why Not Reliabilism?" ............................. 31 Chapter 3 Jonathan L. Kvanvig: "Justification and Proper Basing" ............... 43 Chapter 4 Todd Stewart: "Lehrer on Knowledge and Causation" ................ 63 Chapter 5 Volker Halbach: "Can we Grasp Consistency?" ..................... 75

COHERENCE AND PERSONAL JUSTIFICATION. . . . . . . . . . . . . . . .. 89 Chapter 6 Glenn Ross: "Reasonable Acceptance and the Lottery Paradox: The Case for a More Credulous Consistency" ....................... 91 Chapter 7 Charles B. Cross: "Relational Coherence and Cumulative Reasoning" . .. 109 Chapter 8 Wolfgang Spohn: "Lehrer Meets Ranking Theory" .................. 129 Chapter 9 Carl G. Wagner: "Two Dogmas ofProbabilism" .................... 143

vi TRUSTWORTHINESS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 153 Chapter 10 James Van Cleve: "Lehrer, Reid, and the First of All Principles" ....... 155 Chapter 11 G. J. Mattey: "Self-Trust and the Reasonableness of Acceptance" ...... 173 Chapter 12 Richard N. Manning: "The Dialectic Illusion ofa Vicious Bootstrap" ... 195

UNDEFEA TED JUSTIFICATION AND THE GETTlER PROBLEM .. 217 Chapter 13 Hans Rott: "Lehrer's Dynamic Theory of Knowledge" ............... 219 Chapter 14 Gordian Haas: "Some Remarks on the Definition of Lehrer's Ultrasystem" ......................................... 243 Chapter 15 Jacob Rosenthal: "On Lehrer's Solution to the Gettier Problem" ....... 253

SKEPTICISM .............................................. 261 Chapter 16 John W. Bender: "Skepticism, Justification and the Trustworthiness Argument" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 263 Chapter 17 Peter Klein: "Coherence, Knowledge and Skepticism" ............... 281 Chapter 18 David A. Truncellito: "The Ultrasystem and the Conditional Fallacy" ... 299 Chapter 19 Keith Lehrer: "Coherence, Circularity and Consistency: Lehrer Replies" ............................................. 309

PREFACE Few have contributed so much to the articulation and defense of internalism and the coherence theory as Keith Lehrer. Thanks to his persistent efforts, we are in a better position to appreciate their consequences and assess their tenability. The authors who have contributed to this book were asked to take a closer look at Lehrer's epistemology from their own different perspectives. Many are, of course, critical; that is in the nature of the game. But the reader will also find several constructive attempts to defend or improve on Lehrer's theory. In the final essay, Lehrer gives his replies. All articles appear here for the first time. I am personally indebted to Keith Lehrer in many different ways. Most importantly, his Theory of Knowledge was the first book I read on epistemology, and it made me start thinking seriously about the subject. I never stopped. In recent years I have had the great pleasure of meeting Keith and discussing philosophical issues with him on several occasions. I take the opportunity here to express my gratitude for this and also for his support and practical advice in connection with this book project. Ann Hickman has done an excellent job in preparing the book for publication, for which I am extremely grateful. Thanks also to Christopher von Buelow and Radu Dudau for their editorial assistance. Finally, my warm thanks goes to all contributing authors for their dedication and commitment. My own work was financed by the German Research Council (Deutsche Forschungsgemeinschaft) as a contribution to the research project Logic in Philosophy (Logik in der Philosophie). Involved in this research project, among the authors, are also Wolfgang Spohn, Hans Rott, Volker Halbach and, as associated members, Gordian Haas and Jacob Rosenthal. Erik J. Olsson

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Introduction THE EPISTEMOLOGY OF KEITH LEHRER Erik J. Olsson University of Constance

Fido sees that there is a bone on the plate, but does Fido know that there is a bone on the plate? David, a two-year-old, sees that the door to the refrigerator is open, but does he know that it is open? Examples such as these prompt very different reactions from philosophers. Some think it is obvious that Fido and David know, and that they know in the same sense as adult humans do. Others respond, equally emphatically, that they do not know, at least not in the same way as adult humans. Philosophers ofthe latter inclination may grant that someone who believes that Fido knows is allowed to use the term 'know' in any way he or she wishes and, further, that there might be some point in defining a concept of knowledge applicable also to Fido; but, they will urge, that concept will not be of great interest if what we really care about is human knowledge in its characteristic form. Keith Lehrer belongs to the second category of epistemologists for whom the mere possession of correct information is insufficient for human knowledge, however reliable the source delivering the information may have been. In order to know one must, in addition, recognize that the information one possesses is correct. This additional demand for reasons internal to the subject -characteristic of the position known as internalism-excludes poor old Fido, and probably also David, neither of whom can plausibly be credited with the conceptual resources required for such recognition, for "[t]hey lack any conception of the distinction between veracity and correct information, on the one hand, and deception and misinformation, on the other" (Lehrer, 2000, p. 11). Why is it so important to recognize that one's sources are reliable? Why does it not suffice that they actually are reliable, that the belief was caused in a reliable way? Lehrer's answer, if! understand him correctly, is that the role of E.J. Olsson (ed.), The Epistemology of Keith Lehrer, 1-20. © 2003 Kluwer Academic Publishers.

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knowledge in human reasoning is essential to its nature (ibid., p. 6), and one role of knowledge concerns its employment in reasoning, e.g., in confirming some hypotheses and refuting others. It is essential to knowledge that it enables us to "reason about what is true or false, what is real and unreal" and to justify our knowledge claims "in critical discussion and rational confrontation" (ibid., p. 11). Thus, knowledge, as Lehrer conceives it, is, in its essence, "inextricably woven into reasoning, justification, confirmation, and refutation" (ibid., p. 6). An externalist will certainly agree that knowledge plays an important role in reasoning, but he or she will typically resist the conclusion that this role is essential to its nature. He or she will concede that it is a good thing to have reasons for one's beliefs-for instance, in convincing others that we know-while insisting that having such reasons is not an ingredient in the very concept of knowledge (see for instance Dretske, 1991). An externalist might even grant that having reasons is part of the pre-systematic concept of knowledge, and yet argue that there are good grounds, in this case, to depart from it in favor of an allegedly more fruitful externalist conception. Several of the papers in this volume address, directly or indirectly, the internalism/externalism issue, e.g., the articles by Ernest Sosa, John Greco, and Volker Halbach. Lehrer's view on justification and causation is discussed in the papers by Jonathan L. Kvanvig and Todd Stewart. Highly relevant in this connection is also the article by James Van Cleve. The main purpose of this introduction is to survey the main ideas in Lehrer's epistemology, so as to provide the necessary background against which the other papers in this volume can be more readily appreciated. Another aim is to point out what might be some difficulties in Lehrer's view. A majority of these issues are explored in greater detail in the other contributions to this book, and I have added references to guide the reader to the corresponding places. This introduction, then, is also intended to serve as a conceptual and argumentative map of the present book. Unless otherwise indicated, references to Lehrer are to the 2000 edition of his Theory of Knowledge (abbreviated TK). Theory of Knowledge, an extended and thoroughly revised version of Lehrer's early book Knowledge, was published for the first time in 1990. Between the two editions there are some interesting differences that will play a role later in this introduction.

1.

COHERENCE AND PERSONAL JUSTIFICATION

Lehrer subscribes to a traditional post-Gettier analysis of knowledge, according to which a subject S knows that p if and only if (i) p is true, (ii) S accepts that p, (iii) S is (personally or subjectively) justified in accepting that p, and (iv) S is justified in accepting that p in some way that does not depend on

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a false statement. The last clause is intended to take care of troublesome Gettier examples, a topic I will return to later. The particular interest of Lehrer's theory lies of course in its details. Taking truth for granted, let us focus first on the condition of acceptance: for S to know that p, S must accept that p. Why "acceptance" and not "belief', and what might be the difference between the two? Acceptance, Lehrer writes, is an attitude defined in terms of some purpose and involves an evaluation of whether the attitude fulfills the purpose. Moreover the special kind of acceptance relevant to knowledge is acceptance for the purpose of "attaining truth and avoiding error with respect to the very thing one accepts" (p. 13): to accept that p if and only ifp. Belief, on the other hand, is not defined in terms of a purpose. Belief may happen to serve the purpose of attaining truth and avoiding error but it is not defined in terms of that, or any other, purpose. We may, to take Lehrer's example, believe that a loved one is safe because of the comfort of believing this, and not because of an intrinsic interest in the truth of the matter. Belief, Lehrer argues, is not the attitude characteristic of genuine knowledge; acceptance is. Another feature of acceptance that will playa role later is that it is a functional state, being characterized by the role it plays in thought, inference and action. Obviously much hinges on the third condition of personal justification. In Lehrer's view, such justification amounts to coherence with a background system. The relevant background system---called the evaluation system -consists of three parts: the acceptance system, the preference system and the reasoning system. The acceptance system is the core of the evaluation system and is defined as the set of states of acceptance of S described by statements of the form "S accepts that p" attributing to S just those things S accepts at t with the objective of obtaining truth and avoiding error with respect to the content accepted, that is, with respect to the content that p (p. 130). In the 1990' sedition of TK, the background system was equated with the acceptance system. Suppose, to take an example, that S accepts that Paris is the capital of France. That might lead one to expect that the statement "Paris is the capital of France" should be an element of S's acceptance system. But this, as we just saw, is not how Lehrer defines the notion. Rather, the acceptance system contains the statement "S accepts that Paris is the capital of France". So, when Lehrer writes that in personal justification we must start with what we accept (p. 123), this does not mean that we are allowed to take the truth of "Paris is the capital of France" and other propositions we accept for granted. It means only that we may take for granted that we accept those things, i.e., that we take a certain attitude, that of acceptance, towards those propositions. Lehrer sometimes calls the set of all propositions p such that "S accepts that p" is in the acceptance system the content of that system, a practice I will follow here.

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The preference system of Sat t over acceptances is defined as the set of states of preference described by statements of the form "S prefers accepting that P to accepting that q" attributing to S just those preferences S has at t with the objective of obtaining truth and avoiding error with respect to the contents of the acceptances. Finally, the reasoning system of S at t is the set of states of reasoning described by statements of the form "S reasons from acceptance of the premises PI' P2' and forth to Pj to acceptance of the conclusion COO with the objective of obtaining truth and avoiding error with respect to the content of the acceptances. What is Lehrer's motivation for introducing the preference and reasoning systems as part of the evaluation system? As for preferences, he writes the following in his book Self- Trust (pp. 27-28): "I have said before that a person is personally justified in accepting something if and only if acceptance of it coheres with the acceptance system of the person. I now think that will not suffice, because preferences are also essential to the kind of coherence that yields justified acceptance." It is also of interest to note that, in Lehrer's view, the justification of preferences parallels the justification of acceptances: "Thus, personally justified acceptance, acceptance justified for me, is acceptance that coheres with an evaluation system including preferences, just as personally justified preference, preference justified for me, is preference that coheres with an evaluation system that includes acceptances" (ibid., p. 28). I will return to the reasoning system in connection with the Gettier problem. So much for the evaluation system. Justification, we are told, is coherence with that system. How, then, should we understand coherence? The intuitive idea is that we can think of all sorts of objections an imaginative critic may raise to what a person accepts. These objection might be directly incompatible with what the person accepts or they might, while being compatible with the thing accepted, threaten to undermine my reliability in making assessments of the kind in question. For instance, a critic might object to my claim that I see a tree by suggesting that I am merely hallucinating. That would be an example of the first sort of objection. As an example of the second sort, we might take a case in which the critic replies that I cannot tell whether I am hallucinating or not (Lehrer, 1989, p. 253). Coherence, and personal justification, results when all objections have been met. Thus, the process of justifying a claim has the character of a game with the objections and answers being the different moves the players can make. Lehrer, fittingly, calls it the justification game. If all the objections raised by the critic can be met, then the claimant wins the game. If she wins the game, her original claim coheres with the evaluation system and she is personally or subjectively justified in accepting her original claim; ifnot, she is not justified in her acceptance (TK, 1990b, p. 119). Lehrer is careful to point out that the justification game is only a "heuristic device for understanding the

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considerations that make a person justified in accepting something rather than a psychological model of mental processes" (ibid.). Leaving heuristic considerations aside, Lehrer's semi-formal definition ofjustification runs as follows: S is personally justified in acceptingp at t if only if p coheres with S's evaluation system at t. Further, p coheres with S's evaluation system at t if and only if all objection to p are answered or neutralized relative to S's evaluation system at t. This raises the question of how the notion of an objection should be understood, and what it might mean that an objection is answered or neutralized relative to an evaluation system. Lehrer defines the notion of an objection as follows: 0 is an objection to p if and only if it is more reasonable to accept that p on the assumption that 0 is false than on the assumption that 0 is true (relative to S's evaluation system and t). An objection o to p is answered, moreover, if and only if 0 is an objection to p, but it is more reasonable for S to accept p than to accept 0 (with the appropriate relativizations). In the 1990 edition of TK, objections were called "competitors" and answered objection were said to be "beaten". Before citing Lehrer's definition of neutralization, it might be helpful to consider an example. Suppose I claim to be seeing a zebra and I am faced with the objection that I am sleeping and dreaming that I see a zebra. Then I might be in a position to answer this objection by showing how it follows from my evaluation system that it is more reasonable that I am actually seeing a zebra than that I am merely dreaming that I see one. But suppose the critic instead were to object merely that people sometimes dream that they see zebras. This is an objection, in Lehrer's technical sense, to my claim that I see a zebra; for it is less reasonable to accept that I actually see a zebra if people sometimes dream that they see zebras than if people never dream that they see zebras. And yet it may be very difficult to answer this objection by showing that it is less reasonable to accept than my claim that I see a zebra for the simple reason that it is very reasonable to accept that people sometimes dream they see zebras. In order to allow the claimant to counter objections of this sort, Lehrer introduces the notion of neutralization. The idea is that I should be allowed to counter an objection by pointing out its irrelevance to the issue. In this case, I would be allowed to reply that the objection that people sometimes dream that they see zebras is irrelevant because I am not dreaming. Lehrer defines neturalization as follows: n neutralizes 0 as an objection to p if and only if 0 is an objection to p, the conjunction of 0 and n is not an objection to p, and it is as reasonable for S to accept the conjunction of 0 and n as to accept 0 alone (with the appropriate relativizations). In the example the conjunction that people sometimes dream they see zebras and that I am not dreaming is not an objection to my seeing a zebra. Moreover, it is, we grant, as reasonable for me to accept this conjunction as it is to accept that people sometimes dream they see zebras alone.

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It is not evident that this is the correct way of defining neutralization. Moreover, on pain of triviality, this definition rules out a probabilistic interpretation of reasonableness. For, disregarding some uninteresting limit cases, a conjunction is always less probable than its conjuncts. Hence, on a probabilistic reading of reasonableness a conj unction can never be as reasonable as one of its conjuncts, which means that no objection can be neutralized. For more on comparative reasonableness and neutralization, see the contributions to this volume by Glenn Ross, Charles B. Cross, and Wolfgang Spohn. A related problem in the theory of probability is explored in Carl G. Wagner's paper. Also relevant in this connection are the contributions by G. J. Mattey and Hans Rott. Glenn Ross looks at Lehrer's theory from the point of view of the lottery paradox. The reader might wish to consult Olsson (1998) for another perspective on Lehrer's treatment of the paradoxes of justification. The part of Lehrer's theory that I have outlined so far is intended to specify under what conditions a person is justified in accepting a proposition from the point of view of that person's own evaluation system. But it also suggests a solution to another problem, viz., the problem of specifying rules for inductive inference. This problem can be stated in the following form: Given a set of propositions that I accept, what am I entitled to accept in addition? Obviously I should be allowed to accept everything that follows logically from what I accept. More interestingly, I might also be entitled to accept some propositions which, although they do not follow logically from what I accept, are nevertheless very plausible on that basis. Lehrer's theory suggests the following solution to this problem: in addition to what I accept, I may accept all propositions that cohere with what I accept. The problem of inference is not exactly the same problem as Lehrer's problem of justification, if only because, for the purposes of inductive inference, we would like to start with what we accept and not merely with reports about what we accept. There are also indications that the problem ofjustification, as Lehrer sees it, is one ofjustifying acceptance based on some sort of input (in the form of reports), whereas the problem of inductive inference is one of adding things in the absence of input. 1 The fruitfulness of Lehrer' s semi-formal theory of personal justification for the purposes of inductive inference is explored, in this volume, by Charles B. Cross and Wolfgang Spohn. See also Hans Rott's contribution.

2.

TRUSTWORTHINESS

Where does self-trust or trustworthiness come in? Knowledge, as Lehrer defines it, requires personal justification with the evaluation system of the person. But as that system is defined preciously little will be personally justified. Statements of the form ItS accepts that pIt constitute too meager a basis for

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concluding anything interesting about the relative reasonableness of more substantial claims. They are mere reports of what I accept, and little follows unless I can somehow conclude that what they report is true or at least plausible. So how do I get from "I accepts that p" to p itself? Lehrer's answer is to invoke the principle of trustworthiness. In addition to my other acceptances, I must accept that I am trustworthy, that is, I must accept the following principle: (T) I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true.

In the 1990 edition of TK, Lehrer employed the principle of trustworthiness as a principle of detachment, allowing me to detach p from "I accept that p". The 2000 edition is less optimistic in this respect. According to the view stated there, trustworthiness in combination with "I accept that p" does not allow me to conclude that p is true but only my being reasonable in accepting that p. The reasoning leading up to this conclusion-Lehrer's trustworthiness argumentruns as follows: (T) I am trustworthy in what 1 accept with the objective of

accepting something just in case it is true. I accept that p with the objective of accepting that p just in case it is true. Therefore, 1 am trustworthy in accepting that p with the objective of accepting that p just in case it is true. Therefore, 1 am reasonable in accepting that p with the objective of accepting that p just in case it is true. The trustworthiness argument illustrates the alleged explanatory role of trustworthiness. That I am reasonable in accepting that p may be explained by my being trustworthy, provided that the premises of the trustworthiness argument are true. In particular it must be true that I am actually trustworthy, since a false premise does not explain anything. Lehrer stresses that the principle (T) should not be seen as saying that I am always trustworthy. Rather, it is a statement of a capacity or disposition to be trustworthy and is compatible with my failing now and then. Hence, the inference from my general trustworthiness to my being reasonable in accepting p is inductive rather than deductive. Moreover, my trustworthiness is not only a matter of my past track record in obtaining truth and avoiding error. For "I may proceed in a manner that is worthy of my trust in what 1 accept but be deceived through no fault of my own", as would be the case if I were deceived by a Cartesian demon (p. 139). It is only required that "I am as trustworthy as the

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circumstances allow" (p. 140). For more on the intended interpretation of the principle of trustworthiness, see the first chapter in Lehrer's Self-Trust. There are corresponding principles of trustworthiness for the other parts of the evaluations system. Thus I may accept that I am trustworthy in what I prefer with the objective of preferring to accept somethingjust in case it is true. By an argument paralleling the trustworthiness argument for acceptance I may then conclude that I am reasonable in having a given preference. By the same token, I may accept that I am trustworthy in how I reason, from which I may conclude that I am reasonable in my reasoning to a given conclusion. My acceptance of the principle of trustworthiness does not automatically make my other acceptances justified; but it does make them reasonable and hence in that way it contributes to their justification. This raises the question of how to justify trustworthiness itself. Trustworthiness can hardly contribute to the justification of other acceptances unless it is itself justified or at least reasonable. Lehrer's basic answer is that trustworthiness applies not only to other acceptances but also to itself. We recall that, for any proposition p which I accept for the purpose of obtaining truth and avoiding error, I may reason from the acceptance of my trustworthiness to the reasonableness of my accepting that p. As a special case, I may reason from the acceptance of my trustworthiness to the reasonableness of my accepting that I am trustworthy. Lehrer has characterized the special role played by self-trust using an analogy from Thomas Reid: ''just as light, in revealing the illuminated object, at the same time reveals itself, so the principle, in rendering the acceptance of other things reasonable, at the same time renders the acceptance of itself reasonable" (p. 143). Reid's epistemology has had a profound influence on Lehrer's theorizing about self-trust. On Lehrer's interpretation, one of Reid's principles of common sense is applicable to all other principles including itself. See Lehrer (1989) and, for a discussion of Lehrer's Reid interpretation, James Van Cleve's article in the present volume. As in the case of other acceptances, the trustworthiness argument falls short of establishing that I am justified in my acceptance of (1). It only establishes that I am reasonable in my acceptance (provided that the premises are true). For me to be justified in my acceptance of (1), all objections to that claim have to be answered or neutralized. In order to answer or neutralize such objections I will need to refer to other things I accept. Hence, even in the case of (1), background information is required in order for me to be personally justified in accepting it. The principle (1) does not justify itselfbut depends for its justification on the background system of other things we accept. Therefore it would be incorrect to call it a basic belief in the foundationalist sense. Lehrer has suggested that (1) is more like a keystone in an arch. Without the keystone, the

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arch would collapse; at the same time the keystone is supported by the other stones in the arch. Is the circularity involved in the argument from my acceptance of my trustworthiness to the reasonableness of that acceptance a vicious one? Lehrer has argued that it is not vicious by pointing out that his intention is not to use (T) as a premise to prove something to a skeptic, but rather to use it for explanatory purposes, the claim being that the principle of trustworthiness can be used for explaining why it is reasonable for us to accept what we accept. Indeed, the shift from justification to explanation makes it less obvious that the circle is vicious. Lehrer even thinks that circularity in this case may be a virtue rather than a vice. It is, he notices, preferable to leave as little as possible unexplained. Hence, an explanation that does not only explain why other acceptances are reasonable but also why its own acceptance is reasonable is better in this respect that an explanation which accomplishes the former but not the latter. Several contributors to this volume express dissatisfaction with Lehrer's discussion of trustworthiness. As some point out, what Lehrer says about the possible explanatory merits of self-trust seems irrelevant to the issue of justification. Lehrer's view on the matter is examined in the contributions by James Van Cleve, G. J. Mattey and Richard N. Manning. The papers by John W. Bender, John Greco and Peter Klein contain related material. Manning, for instance, contends that difficulties arise because of Lehrer's presupposition that the principle of trustworthiness is something that needs to be argued for in the first place. In Manning's view, by contrast, self-trust is a transcendental condition on the possibility of our epistemic practice.

3.

IN WHAT SENSE IS LEHRER'S THEORY A COHERENCE THEORY?

What has been said so far raises the following question: In what sense, if any, is Lehrer's theory a coherence theory, as Lehrer claims it is (at least in part)? If one takes it as essential that such a theory make use of a concept of systematic or global coherence, then Lehrer's theory is clearly not a coherence theory. For in Lehrer's view, "[c]oherence ... is not a global feature of the system" (1997, p. 31). Rather, what he calls coherence, as we have seen, is a relation between an evaluation system and a proposition. This relation, moreover, "does not depend on global features of the system" (ibid.). This notwithstanding, Lehrer has said that the content of the acceptance system should be logically consistent, thus referring to the global feature of consistency (1991, p. 131). Lehrer has also addressed the issue of consistency in his paper "Reason and Consistency", reprinted as Chapter 6 in Metamind. The role of

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consistency in an internalist epistemology is explored in Volker Halbach's contribution to this volume. What reasons, then, are there for calling the relation of meeting objections to a given claim relative to an evaluation system a relation of coherence? As I understand Lehrer, his answer is that it is a relation of "fitting together with", rather than, say, a relation of "being inferable from". He writes, in the 1990 edition of TK: "[i]f it is more reasonable for me to accept one of [several] conflicting claims than the other on the basis of my acceptance system, then that claim fits better or coheres better with my acceptance system" (p. 116). He also contends that "[a] belief may be completely justified for a person because of some relation ofthe belief to a system to which it belongs, the way it coherence with the system, just as a nose may be beautiful because of some relation of the nose to a face, the way it fits with the face" (p. 88). Lehrer is here claiming that a statement's cohering with a system is analogous with a nose's fitting with a face. However, as I have argued elsewhere (Olsson, 1999), this analogy is incompatible with Lehrer's contention that coherence does not depend on global features of a system. For when we say that a nose fits with a face, we mean that combining the two yields a beautiful overall result, so that the nose fits with the face in virtue of the underlying global property of beauty. If cohering is analogous to fitting, as Lehrer proposes, then a statement coheres with a system if combining the two yields a coherent overall result, so that the statement fits with the system in virtue ofthe underlying global property of coherence. This, again, clashes with Lehrer's declaration that coherence does not depend on global features ofthe system. So Lehrer's relation of coherence with an evaluation system has little to do with coherence properly so called, being more akin to inference. Nevertheless, Lehrer's more recent ideas about trustworthiness are arguably sufficient to turn his theory into a coherence theory after all. As we have observed, there is a circularity involved in the argument from my acceptance of my trustworthiness to the reasonableness of that very acceptance. And a salient feature of a coherence theory is presumably that it licenses circular reasoning-at least this is one popular way of characterizing such a theory.

4.

THE PROBLEM OF PSYCHOLOGICAL REALISM

Externalist theories allow for a modest psychological makeup of the knower. Internalist theories, on the other hand, are typically much more demanding in this respect, insisting that the knowing subject be capable of various higher level cognitive states. Lehrer's internal ism, as we have seen, is no exception to this general rule. According to Lehrer, I am not in a position to

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know, say, that I see a tree over there, unless I also accept my trustworthiness in relevant matters. But is it psychologically realistic to suppose that acceptances about other acceptances-in particular about their trustworthiness-are necessary for knowledge? It seems that people often make perceptual claims without ever having thought about the trustworthiness of their perceptual faculties. Are we then forced to say that they do not know what they claim to know? While Lehrer concedes that some "unrealistic theory of belief maintaining that all beliefs are occurrent states may yield the consequence that we lack such beliefs [about trustworthiness]" (p. 202), he contends that his own theory of acceptance avoids this conclusion. For according to the latter the mental state of acceptance is a functional state, one that plays a role in thought, inference and action. As a consequence, I may be said to accept that p at a time t even if my acceptance ofp is not something I am contemplating at t. What is essential to my acceptance of p is how I think, infer and act. This holds, in particular, for my acceptance of my trustworthiness, which need not be present to my mind either. As Lehrer puts it, "[ w]e think, infer, and act, in a way manifesting our trust in what we accept" (ibid.). He concludes that "it is appropriate and not at all unrealistic to suppose that, in addition to the other things we accept, we accept our own trustworthiness and the reliability of it as well" (ibid.). But does this clever defense against charges of lack of psychological realism really work? Let us first ask this question: What would be the difference between the functional role of my acceptingp only and the functional role of my accepting, in addition, my trustworthiness in matters concerningp? Suppose that I accept that p without accepting my trustworthiness in matters concerning p. This means that I am inclined to think, infer and act in a certain way. More precisely, my acceptance of p amounts to my being "inclined to assent to it automatically, to draw inferences based on the assumption of it, and, in general, to act as though it were true" (Lehrer, 1989, p. 270). For instance, suppose that I am planning to take a walk. My acceptance that it is raining will then manifest itself in my acting as though it were true, e.g., in my being inclined to bring my umbrella. My acceptance that it is raining will also manifest itself in my being inclined to infer, and thus to accept, further propositions as well, e.g., that the ground will be wet. This new acceptance in turn will make me inclined to put on my boots rather than my less sturdy Italian shoes, and so on. Now add to my acceptance that p my further acceptance that I am trustworthy in matters concerning p. My suspicion is that this addition contributes nothing to how I will think, infer and act beyond what was already part of my acceptance of p. To continue the example, my acceptance that it is raining will manifest itself in my being inclined to bring my umbrella and infer that the ground will be wet, and so on. Add to this my acceptance of my trustworthiness in telling whether it is raining or not. This addition has no

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THE EPISTEMOLOGY OF KEITH LEHRER

further effect on my dispositions to think, infer and act. I will still be inclined to bring my umbrella and to infer that the ground will be wet, and no new dispositions to think, infer and act seem to come forth. From the point of view of how I think, infer and act, there is no difference between, on the one hand, my accepting that p and, on the other hand, my accepting that p and, in addition, that I am trustworthy regarding p. Rather, these two descriptions-"my accepting that p" and "my accepting that p and, in addition, that I am trustworthy regarding p"-are merely two different characterizations of one and the same functional state, namely, that in which I accept that p. The upshot of all this is to confront Lehrer with the following dilemma. Without a functional theory of acceptance, his theory is indeed vulnerable to charges of lack of psychological realism. But the same functional theory which solves this problem so neatly has the unwelcome effect of trivia Ii zing the very idea of trustwort hi ness, reducing trustworthy acceptance to mere acceptance. A related objection is raised in John Greco's contribution to this volume.

5.

UNDEFEATED JUSTIFICATION AND THE GETTlER PROBLEM

In a classical paper, Edmund Gettier gave a counter example to defining knowledge as justified true belief. The variation discussed by Lehrer runs as follows. A teacher wonders whether any of her students owns a Ferrari. She has strong evidence that one student, Mr. Nogot, owns one. Mr. Nogot says he owns a Ferrari, he drives one and has all the papers proving that he owns one, and so on. The teacher has no reason to think that there be other Ferrari owners among her students. From her evidence she concludes that Mr. Nogot owns a Ferrari, from which she draws the further conclusion that someone in her class owns a Ferrari. Now, as a matter of fact, Mr. Nogot has lied about the Ferrari. He does not own one and the evidence he has presented was fabricated for the purposes of improving his social status. This notwithstanding, there is another student, Mr. Havit, who does own a Ferrari, though the teacher has no evidence of this. Hence, the teacher's belief that someone in her class owns a Ferrari is true after all. Moreover, being based on good evidence, her belief is also justified. Yet it seems intuitively incorrect to say that the teacher knows that someone in her class owns a Ferrari. Rather, she was just lucky that there was a real Ferrari owner in her class. The teacher's justification for believing that someone in her class owns a Ferrari depends on the false premise that Mr. N ogot owns a Ferrari. Hence, the obvious reaction is to add a fourth requirement to the definition of knowledge to the effect that the subject's knowledge claim not be dependent on a false

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premise. However, as Lehrer notices, one can construct a similar example in which no false premise is in play. For the teacher could conceivably conclude directly from the evidence (Mr. Nogot is a student of my class, he has told me that he owns a Ferrari, and so on) that someone in her class owns a Ferrari without first concluding that Mr. Nogot does. And we tend to think that she would not know that there is a Ferrari owner in her class in this case either. In the 1990 edition of TK, Lehrer suggested an elegant general approach to Gettier type cases. The idea was to consider not only the subject's actual acceptance system but also acceptance systems that can be obtained from that system by removing any false statement or replacing any such statement by its negation. The collection of all systems obtained in this manner he called the ultrasystem of the subject. Lehrer then required that the subject's claim, in order to count as knowledge, be justified relative to all elements of the ultrasystem, in which case the subject's justification was said to be undefeated. It is obvious that this proposal takes care ofthe original Ferrari example. For one element of the ultrasystem is obtained by replacing the claim that Mr. Nogot owns a Ferrari by its negation, so that the teacher is no longer justified in concluding that someone owns a Ferrari. Let us also examine how the proposal applies to the more difficult example in which the teacher never accepted that Mr. Nogot owns a Ferrari in the first place, but concluded directly from the evidence that someone in her class owns one. Lehrer argues that in this case the teacher would nevertheless subscribe to the conditional "If the evidence I have that Nogot owns a Ferrari is true, then Nogot owns a Ferrari". We may now construct an element of the ultrasystem by replacing this conditional statement by its negation, i.e., by "The evidence I have that Nogot owns a Ferrari is true but Nogot does not own a Ferrari". Clearly, the teacher is not justified in accepting that someone in her class owns a Ferrari on the basis ofthe member of the ultrasystem thus constructed, and therefore she does not know what she claims to know. One problem with this intriguing proposal has to do with how to eliminate and replace statements while retaining logical integrity. Suppose that p is to be eliminated (or more exactly "I accept that pOl) and that p is implied by q which the subject also accepts. Then, as Lehrer points out (1990b, p. 141), it is not sufficient just to remove p but q has to be removed as well; otherwise p can be derived back from q. However, as Hans Rott observes in his contribution, and also in his book from 2001, elimination is unexpectedly complicated. The same goes for replacement which is quite a subtle type of change in need of more careful attention. There is an interesting connection here between the 1990 version of Lehrer's theory and the area of philosophical logic called belief revision theory in which problems of the kind just mentioned has been studied independently by logicians since the seventies. This connection is explored in Rott's paper.

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Promising as Lehrer's 1990 solution may seem, the 2000 edition of TK features a substantially different approach to Gettier problems. The new solution is simpler in that only one alternative system is taken into account-the one obtained from the present system by removing all false judgments-and no complicated contractions and replacements are called for. The new solution is more complex in another respect, though, since the system from which judgments are deleted is now the more complex evaluation system and not the simpler acceptance system (which, we recall, is but a part of the evaluation system). Hence not only false acceptances are removed but also preferences for accepting something false over something true as well as unsound patterns of reasoning. The result is called the ultrasystem, a term which has thus been given a new definition? Finally, for the subject to know that p it is necessary that p be justified relative to the ultrasystem. In the preface to the 2000 edition of TK, Lehrer writes that the new solution to Gettier problems is based on a "simplified" and "improved" conception of an ultrasystem, claims that are not substantiated in the course of his book. As we have seen, while the new conception is simpler in some respects, it is more complex in another respect, being based on a more complex conception of a background system. Moreover, it is not clear that the new proposal represents an improvement, since, as I will try to make likely, Lehrer's new treatment of the hard Ferrari example (in which the teacher or claimant concluded directly from the evidence that someone owns a Ferrari) is not entirely convincing. The idea behind what Lehrer calls the ultra justification game is that the ultracritic should try to disprove the claimant on the basis of the claimant's ultrasystem. Lehrer envisages the following ultra justification game to illustrate the outcome of applying his new proposal to the hard Ferrari example: Claimant: Someone in my class owns a Ferrari. If I have the evidence that Nogot owns a Ferrari, that he is student in my class, that he has told me that he owns a Ferrari, that he has shown me papers stating that he owns a Ferrari and that he drives a Ferrari, then Nogot owns a Ferrari. I have all that evidence consisting of true claims. Ultracritic: You must eliminate your hypothetical claim that if you have the evidence that Nogot owns a Ferrari, that he is student in your class, that he has told you that he owns a Ferrari, that he has shown you papers stating that he owns a Ferrari and that he drives a Ferrari, then he owns a Ferrari! The evidence you have that Nogot owns a Ferrari is true, but Nogot does not own a Ferrari. It is not more reasonable for you to accept that someone in your class

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owns a Ferrari than that no one does. No one in your class owns a Ferrari. (My italics.) Lehrer now maintains that the claimant, on the basis of her ultrasystem, will not be able to answer or neutralize the ultracritic's objection. As I understand it, Lehrer's analysis of the hard Ferrari example is intended to illustrate the claim that "[t]he proper solution to these [Gettier] problems may be obtained from the ultrajustification game by extending the role of the critic in the game to include considerations of preferences and reasonings that supplement the acceptance system in the evaluation system of the claimant" (p. 160). Clearly, this particular example must be taken to illustrate considerations of reasonings. Now, the ultracritic may instruct the claimant to give up a piece of reasoning only if that reasoning is unsound. In the example, she instructs her to give up her reasoning from the evidence about Mr. Nogot's driving a Ferrari etc. to his owning a Ferrari. But is that reasoning really unsound? I think not. The fact that the premises are true but the conclusion false in the example only serves to disprove the deductive validity of the inference, but this is beside the point, since the claimant is not committed to its deductive validity but at most to its inductive validity. As an inductive inference it is sound. For the conclusion that Mr. Nogot owns a Ferrari is highly probable on the evidence of his driving one, showing papers stating that he owns one etc. But perhaps Lehrer did not after all intend his new analysis of the hard Ferrari example to illustrate the elimination of reasonings from the evaluation system. Perhaps we should think of the hypothetical linking the evidence about Nogotto his owning a Ferrari not as belonging to the reasoning system butto the acceptance system (as in the 1990 edition of TK). But in that case it is unclear what role the reasoning system plays in Lehrer's analysis of Gettier cases. Does it perform any useful function at all? Hence, it is not evident that Lehrer's new approach to the Gettier problem amounts to an improvement in comparison to the old. Of course, some logicians that were attracted to the 1990 version of Lehrer's theory primarily because of its interesting relationship to belief revision theory will be quite happy with this observation. Yet, Lehrer might be able to derive some support for his new approach from Gordian Haas's article in this volume, in which Haas presents a formal argument to the effect that the complicated elimination and replacement operations occurring in the older approach are actually superfluous. Jacob Rosenthal argues, in his contribution, that both solutions presented by Lehrer are unsatisfactory. Undefeated justification and the Gettier problem are also discussed in the papers by John Greco, Peter Klein and Wolfgang Spohn.

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6.

THE EPISTEMOLOGY OF KEITH LEHRER

THE ANSWER TO SKEPTICISM

What is Lehrer's reply to skepticism? In answering this question I will try to distillate two different and, as I hope to show, conflicting tendencies in Lehrer's work. According to Lehrer, the sophisticated common sense philosopher, there is no need to bother with radical skepticism, and this is so for purely methodological reasons. We can safely assume that we know most of the common sense things we think we know, and we do not have to take various skeptical hypotheses into account. Lehrer, the moderate skeptic, is of a different opinion. According to him, we have knowledge only if we are not systematically deceived. If we are deceived, e.g. by a Cartesian demon, then we do not know anything at all. Let us start with Lehrer, the common sense philosopher. Lehrer addresses skepticism already in the first chapter of TK in which he rejects Cartesian epistemology and its method of pretending to total ignorance in the hope of arriving at something completely certain (p. 2). He rejects it in favor of what he calls critical epistemology which is said to be "neither skeptical nor metaphysical" (ibid.), beginning with "common sense and scientific assumption about what is real and what is known" (p. 3). These convictions, he adds, "constitute our data, perhaps even conflicting data if common sense and science conflict" (ibid.). For example, the critical epistemologist takes for granted the premise that we have knowledge of the internal world of our ideas from consciousness and of the external world of matter from observation (p. 4). The object of philosophical inquiry in general, and critical epistemology in particular, is to account for the data in a way that is "systematic and critical" (p. 3). That it is critical means that "[s]ometimes we explain the data and sometimes we explain the data away" (p. 4). The best systematic account of the data may be one which, "in a few instances" (ibid.), does not classify as knowledge what was classified as such by common sense. For instance, such data would include my claims that I know that I am sitting before my computer now, that Paris is the capital of France, that George W. Bush is the president of the United States, and so on. It would be the job of the critical epistemologist to find what is common to all, or most, of these presumed instances of knowledge, e.g., thatthey have been derived from reliable sources, or are examples of justified true beliefs, and so on. A few pages later, Lehrer clarifies the task of the critical epistemologist further by saying that she should aim at explicating concepts in the sense of RudolfCarnap, i.e., by generating new philosophically and scientifically useful concepts. Carnap required of an explication that the explicatum (the concept resulting from the explication) be (1) similar to the explicandum (the original pre-systematic concept that is to be explicated), (2) exact, (3) fruitful and (4) simple. More precisely, the explicatum should be similar to the explicandum in

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such a way that the explicatum can be used in most cases in which the explicandum has so far been used, but the similarity need not be very close. The explicatum, besides being exact, should also be fruitful in the sense of being useful for formulating universal statements (empirical laws and logical theorems). Finally, the explicatum should be as simple as the other more important desiderata permit. Lehrer's characterization of critical epistemology conveys the impression that he is essentially a common sense philosopher in the tradition of G. E. Moore. Like G. E. Moore, he repudiates the idea that epistemology should engage in radical doubt concerning common sense knowledge claims. Yet being based on a general view as to the nature of philosophical and scientific definitions, Lehrer's approach is more sophisticated than Moore's position, which, lacking a more solid methodological foundation, amounts to ruling out skepticism on the sole grounds that it conflicts with common sense. It is not difficult to appreciate that from the point of view of Lehrer's critical epistemology, even in the sophisticated form referring to Carnap's notion of explication, radical skepticism can be dismissed for methodological reasons alone. For a radical skeptic will want to define knowledge so that most or all of our common sense knowledge claims turn out false, e.g., by insisting that anything worthy of the name must be such that there is no logical possibility of error. Hence, any such attempt will score very poorly as regards Carnap' s criterion of similarity to the explicandum. To compensate for this, it would have to do extremely well in other respects, i.e., regarding exactness, fruitfulness and simplicity. But even ifit can be given an exact and simple definition, a skeptical conception of knowledge will be a complete failure with respect to the important desideratum of fruitfulness: a concept under which nothing, or very little, falls will be utterly useless for articulating laws and theories. We would not accept a definition of water that makes nothing qualify as water; and we should be equally discontent with a definition of knowledge that makes nothing qualify as such. Almost any other proposal one could think of will fare better. The (sophisticated) common sense position is presented in the introductory chapter of TK, but its influence seems to decline as the book develops, and in Chapter 9 radical skepticism makes a surprising comeback as an epistemological threat that must be "answered". Lehrer's reasoning in defense of what is, in effect, a moderate skepticism is not easy to follow, and I will not be able to cover all details here. Nonetheless, the main idea seems to be the following. We cannot rule out the possibility that we may be in error regarding what we accept because of the general fallibility of our faculties and because we may be deceived by a Cartesian demon. However, our fallibility does not imply a lack of personal justification on our part in accepting what we do accept. For we may still be able to answer or neutralize all objections on the basis of our acceptance system, or so Lehrer claims. This is accomplished by our

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acceptance of our own trustworthiness which serves to neutralize all objections referring to our fallibility (p. 220). Recall that, in general, n neutralizes 0 as an objection to p if accepting the conjunction of 0 and n is not an objection to p and is as reasonable as to accept 0 alone (relative to a person, an evaluation system and a point in time). The principle of trustworthiness neutralizes fallibilism as an objection to any specific knowledge claim since it is, Lehrer contends, as reasonable to accept both that we are fallible and that we are trustworthy as it is to accept that we are fallible alone. This last step is clearly one of the weaker links in Lehrer's argument, and, to the best of my knowledge, Lehrer has presented no detailed argument in its support. To continue the argument, personal justification is not sufficient for knowledge. In order for me to know, my personal justification must be undefeated by errors in the evaluation system. For instance, it must be true that I am really trustworthy, or the neutralization of the fallibilistic objection will fail relative to the ultrasystem. In short, if there is a demon, I will fail to know even the most basic thing: "[i]fwe were massively mistaken, as we would be if the Cartesian demon were loose in the land, then we would lack knowledge" (p. 209). On the other hand, if there is no demon, I will presumably know most common sense things. Lehrer's argument does not allow us to conclude, on good grounds, that we have knowledge. On the other hand, we may not conclude that we are ignorant either. Whether we know or not depends on whether we are systematically deceived or not. Since, as a matter of principle, we can have no empirical evidence either for or against systematic deception, I take it that Lehrer's moderately skeptical concept of knowledge will be useless in formulating empirical laws and theories. This is, of course, a problematic fact on the background of Lehrer's methodological reliance on Carnap's notion of explication. This moderately skeptical view should be contrasted with what I take to be Lehrer's common sense position, according to which we do have knowledge whether we are systematically deceived or not (if systematic deception is at all regarded a serious possibility). It should also be distinguished from radical skepticism, or at least one form of it, according to which we are ignorant whether we are systematically deceived or not. Lehrer, the common sense philosopher, is in conflict with Lehrer, the moderate skeptic. For, as I interpret the former, he is saying that we have knowledge even if we are systematically deceived. This is denied by the latter, according to whom systematic deception implies ignorance. For reasons already noted, I find the view of Lehrer, the moderate skeptic, unconvincing. A crucial step relies on the rather vague idea of comparative reasonableness and, more fundamentally, it is unclear to me what the methodological basis for his answer to skepticism might be. On the other hand,

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I have great sympathy for Lehrer, the sophisticated common sense philosopher, who has a simple and, in my view, entirely satisfactory answer to skepticism based on some general methodological considerations concerning the nature of philosophical and scientific definitions. Lehrer's answer to skepticism is critically assessed in the contributions by John W. Bender and Peter Klein. There is also the issue of whether Lehrer's theory implies radical skepticism concerning facts of acceptance. Robert Shope (1978) has argued that Lehrer, in his account of undefeated justification, commits the "conditional fallacy". A similar objection is raised by Peter Klein in this volume. Suppose that I accept some proposition p which is actually false. While p's falsity prevents me from knowing that p, it should not prevent me from knowing that 1 accept that p. But Lehrer's theory seems to have just this consequence: if p is false, 1 cannot know even that 1 accept that p. The reason is that "I accept that p" will not be in the ultrasystem, making it impossible for me to answer or neutralize the objection that 1 do not accept that p. Lehrer, as a matter of fact, has addressed this problem in the latest edition of TK, in which the ultrasystem is required to acknowledge the existence of the eliminated states of acceptance, preference and reasoning in the original evaluation system (p. 160). The conditional fallacy is discussed in David A. Truncellito's contribution to this volume. Truncellito maintains that the objection rests on a misunderstanding of Lehrer's account. The purpose of this introduction has been merely to give a brief overview of Lehrer's theory of knowledge and justification, and to indicate what might be possible troubles. It goes without saying that there is much more to be said about Lehrer's epistemology. My perhaps most serious omission concerns his and Carl G. Wagner's celebrated theory of rational consensus which they have developed in a series of papers and an influential book, Rational Consensus in Science and Society. Wagner's paper in the present volume discusses some probabilistic issues of importance to this other, no less important, aspect of Lehrer's epistemological theorizing. 3

ENDNOTES 1 Lehrer writes on p. 10 in TK: "We shall be concerned with an analysis that will be useful for explaining how people know that the input (the reports and representations) they receive from other people, their own senses, and reason is correct information rather than error and misinformation. A person may receive a representation that p as input without knowing that the representation is correct and, therefore, without knowing that p." 2 For reasons that that will emerge later, the ultrasystem is also required to acknowledge the existence ofthe eliminated states of acceptance, preference and reasoning in the original evaluation system (p. 160). 3 Thanks are due to Gordian Haas for his comments on an earlier version of this introduction.

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REFERENCES Carnap, R. (1950), Logical Foundations ofProbability, The University of Chicago Press, Chicago. Dretske, F. (1991), "Two Conceptions of Knowledge: Rational vs. Reliable Belief', Grazer Philosophische Studien, Vol. 40: 15-30. Lehrer, K. (1974), Knowledge, Clarendon Press, Oxford. Lehrer, K. (1975), "Reason and Consistency", in Analysis and Metaphysics: Essays in Honor of R, M Chisholm, Lehrer, K. (ed.), Dordrecht. Lehrer, K. (1989), "Reply to My Critics", in The Current State ofthe Coherence Theory, Bender, J. W. (ed.), Philosophical Studies Series, Vol. 44, Kluwer, Dordrecht. Lehrer, K. (I 990a), Metamind, Clarendon Press, Oxford. Lehrer, K. (1990b), Theory of Knowledge, First Edition, Westview Press, Boulder. Lehrer, K. (1991), "Reply to Mylan Engel", Grazer Philosophische Studien, Vol. 40: 131-133. Lehrer, K. (1997), Self-Trust: A Study of Reason, Knowledge and Autonomy, Clarendon Press, Oxford. Lehrer, K. (2000), Theory of Knowledge, Second Edition, Westview Press, Boulder. Lehrer, K, and Wagner, C. G. (1981), Rational Consensus in Science and SOCiety, Reidel, Dordrecht. Olsson, E. 1. (1998), "Competing for Acceptance: Lehrer's Rule and the Paradoxes of Justification", Theoria, Vol. 64: 34-54. Olsson, E. J. (1999), "Cohering With", Erkenntnis, Vol. 50, Nos. 2-3: 273-291. Rott, H. (2001), Change, Choice and Inference, Oxford Logic Guides No. 42, Oxford University Press. Shope, R. (1978), 'The Conditional Fallacy in Contemporary Philosophy", Journal ofPhilosophy, Vol. 75: 397-413.

EXTERNALISM VS. INTERNALISM

Chapter 1 EPISTEMOLOGY: DOES IT DEPEND ON INDEPENDENCE?1 Ernest Sosa Brown University and Rutgers University

It is Lehrer's epistemology that most engages me, and that is what I will focus on here, while acknowledging his more recent extraepistemological analogies and comparisons, and the parallel forms of reasoning that he uncovers concerning ethics, and even wisdom, autonomy, and love. Perhaps we will go astray in abstracting thus from the broader context. If so, I hope Keith will set us straight. Let me begin with a word of explanation about my title. Independence there is Lehrer's term, by which he means non supervenience. And here is the question on which I will focus: What is the place of supervenience in epistemology? Most epistemologists take epistemology to include as a central concern the study of normative epistemic statuses such as epistemic justification, warrant, rationality, reasonableness, and knowledge itself. It is widely held that although the normative is not definable in terms of the nonnormative, nevertheless it does supervene on the nonnormative. Recall the notorious naturalistic fallacy. The mistake there is essentially that of trying to define the normative through the nonnormative. It was G.E. Moore who brought that fallacy to our attention, but Moore himself also advocated a thesis of the supervenience of the normative on the nonnormative. As for the supervenience of the epistemically normative, that would seem just a special case of the supervenience of the normative generally. Again, the orthodox stance has it that epistemic justification and other normative epistemic statuses supervene. This is often just taken for granted as it silently structures reflection and research in the field. Main controversies, such as internalism/externalism and foundationalism/coherentism, can often 23 E.!. Olsson (ed.), The Epistemology of Keith Lehrer, 23-30. © 2003 Kluwer Academic Publishers.

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be seen as disagreements over the general shape of how justification supervenes. Occasionally this becomes explicit, especially in recent work. For example, in a recent defense of epistemic internal ism, Conee and Feldman call their version mentalism, which is the thesis that the epistemic justification of any belief supervenes on the mental properties of the believer. I myself favor the boringly orthodox stance. Lehrer, by contrast, has argued for the more exciting contrarian view, that the epistemically normative does not supervene. Excitingly contrarian views are bound to meet resistance, however, and in keeping with my role as commentator I intend in what follows dutifully to resist. In epistemology, Lehrer has been a vigorous opponent of externalism and foundational ism. Together with Bonjour and others influenced by Wilfrid Sellars, he has rejected simplistic thermometer conceptions of knowledge as belief with appropriate causal, or tracking, or reliabilist properties. These properties may all remain outside the relevant grasp of the believer, after all, in which case they can give him "information" but hardly knowledge. What more is required? Here Lehrer's internal ism and coherentism come to the fore. To know that p, one needs a coherent perspective wherein one "accepts that p with the goal of gaining truth and avoiding error." Accepting that p is not just believing it. It is rather an evaluative stance on the question whether p, to the effect that it is advisable to accept it, with a view to gaining truth and avoiding error. No matter how coherently and deeply one might defend one's acceptance of p with further supportive acceptances, however, this will not ensure that one knows, since one's justification can still be defeated. How so? Through the falsity of enough of the supportive structure that lends coherence to one's acceptance ofp. Either one's justification is defeated, then, or it is not. If one's justification is defeated, if the removal of falsehood does entail the loss of sufficiently coherent support, then one's acceptance of p is justified personally but not also verifically. If one's justification is not defeated, on the other hand, if one's accepting p is still supported with sufficient coherence even after the removal of all such falsehood, then one's acceptance of p is justified both personally and verifically. It is one's acceptance system in the search for truth (and avoidance of error) that determines what one is justified in accepting. Only what coheres with one's system is one justified in accepting. How then does acceptance of a hypothesis cohere with such a system? This is detailed through a complex set of definitions, but the key idea is that accepting the hypothesis needs to be reasonable enough in the light of the acceptance system. (Here I am simplifying by focusing on the acceptance system, whereas Lehrer's more recent, fuller view would replace the acceptance system with the so-called

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evaluation system, which includes not only acceptances and evaluations of acceptances of various sorts, but also preferences and evaluations of preferences of various sorts. My simplified account is thus a caricature, but one that does, I hope, still convey, perhaps more vividly, key features of the epistemology proper.) Crucial to Lehrer's defense of such coherentism is his claim that the epistemic does not supervene on the nonepistemic and natural. In his view, only this rejection of supervenience enables him to defend his favored coherentism from its rival, foundationalism. So how should we understand the rejected supervenience thesis? What is the supervenience at issue? Properties X supervene on properties Y if and only if whenever an X property is exemplified, this follows necessarily from the exemplification of a Yproperty.

That then is what is required for epistemic properties of beliefs to supervene on their natural, nonepistemic properties. According to Lehrer, no such requirement is satisfied by the epistemic relative to the nonepistemic: there are no nonepistemic, natural properties and relations, such that whenever one reasonably accepts something, this is entailed by the fact that one's acceptance exemplifies such natural properties or enters into such natural relations. One might take coherentism to offer an advantage over foundationalism for those who prize explanation. Thus compare the following two principles: one foundationalist, one coherentist. (F)

IfNBp, then Jp, where NB is a naturalistic property of basic beliefs and J is a property of justification. To the question, why are we justified in accepting that p ifNB of p, the answer is that we just are ... 2

(CSR)

If S has an evaluation [acceptance] system A which contains (CSR) and p n-coheres with A, then S is justified in accepting that p.

If On-coheres' were defined non-epistemically, perhaps in terms of some naturalistic probability relation such as relative truth frequency, this principle could be construed as a principle of supervenience .... 3

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Now, it may be thought an advantage of CSR-coherentism that one could explain one's justification for acceptance of CSR by appeal to CSR itself, so long as CSR itself n-coheres with one's evaluation [acceptance] system A. It may be thought that F would be denied this explanatory advantage. But this is only an illusion. After all, there is no reason why F could not itself have foundationalist property NB, in which case the foundationalist could equally explain his justification for accepting F by appeal to F itself. Having recognized that no advantage accrues to coherentism through the reasoning just reviewed, Lehrer reacts as follows: If we are interested, therefore, in arguing that the coherence theory has an advantage in explaining why things are justified that the foundations theory must lack, we must reject the thesis of supervenience and argue for a coherence theory that makes justification independent [non supervenient]. Moreover, we must do this in such a way as to show why coherence leads to the doctrine of independence and the foundations theory does not. But how can we accomplish this? What is there about coherence that yields independence?4

"The answer, in brief, is that an adequate account of coherence must involve epistemic notions." Lehrer argues for this both with regard to the undefeated justification requisite for knowledge and also with regard to the personal justification requisite for undefeated justification. I confess that the structure of Lehrer's argument for this stance is not crystal clear to me. So far as I have been able to get it in focus, however, it seems to depend on a point made for example in the following two passages: ... I am trustworthy in what I accept only if I can tell whether I am trustworthy or not. I must be able to tell whether I am trustworthy or not about something in order to be trustworthy about it. I must accept that I am trustworthy when I am and not accept that I am trustworthy when I am not, at least a trustworthy amount of the time. 5 ... if I am asked how often a person must be correct in order to be trustworthy over time, I can only say, uninformatively, that he must be right a trustworthy amount of the time. 6

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If I have understood him properly, Lehrer reasons that even so much as personal justification requires that the subject be trustworthy enough, and there's no specifying in nonepistemic terms how trustworthy that needs to be. So even the most basic epistemic state, personal justification, will fail to supervene on the nonepistemic. Equally, therefore, will the more complex epistemic states, of verific justification and of knowledge, also fail to supervene, constituted as they are out of personal justification. 7 I have the following three questions about this way of reasoning in favor of coherentism and against supervenience. 1. Even if the relevant epistemic statuses, of knowledge, say, and of epistemic reasonability and justification, are to be understood in terms of coherence, and even if an adequate "account" of coherence must involve epistemic notions, how does this refute the supervenience of the epistemic? Compare tallness. It may be that there is no way to define 'tall relative to group G' without using tallness terminology. Thus it may not be possible to do so without using the predicate "sufficiently taller than the average" or the like, which will only raise the question "Sufficiently for what?"-to which the only acceptable answer may be "Sufficiently to make one tall." Yet, even if any adequate account of tallness must in that way involve tallness notions, so that in effect there is no acceptable noncircular definition of that notion, surely tallness does supervene on the distribution of heights over the relevant group. Moreover, the point here need not be restricted to relative terms such as 'tall' and its cognates. It would seem to apply well beyond that, to any terms that while indefinable in terms of some basis still supervene on that basis. (And the point would apply not only to definability but also to reducibility, if the standards for biconditional reducibility are set lower than those for outright definability. It would still be plausibly arguable that failure of biconditional reducibility to a certain basis is compatible with supervenience on that basis.) Suppose we do need to appeal in our explication of our concept of tallness, such as it is, to "sufficiently taller than the average to make one tall." Surely we can still insist quite plausibly that whenever someone S is tall (relative to group G) this follows necessarily from the distribution of heights in group G, including S's own height. Moreover, it would still seem plausible that, relative to any possible counterpart group with the same distribution of heights, necessarily the counterpart of subject S would also be tall (relative to the counterpart of group G) as a necessary consequence of that distribution of heights. Note, moreover, that it does not matter for our purposes how the people in that counterpart group use the word 'tall' or what contextual variation there might be to their proper and truthful application of that word.

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That does not affect the truth or falsehood of what we say when we say that in that group what matters to whether the counterpart of S is tall is the distribution of heights in the group. Here we are of course relying on what we mean by 'tall' and on whatever contextual constraints there may be on our present proper and truthful use of such terminology. So it is important to distinguish our question of whether tallness-relative-to-G supervenes on the distribution of heights alone, from the question of whether the correctness of applications of 'tall (for group G)' in group G is entailed simply by the distribution of heights. (Obviously it is not entailed simply by that; such correctness is also crucially dependent on the standards operative in group G for the use of the relevant terminology, which need not coincide with our standards. ) Our question should also be distinguished, moreover, from the question whether our attributions of 'tall (for group G)' have their correctness determined simply by the distribution of heights. Here again, the answer to our correctness-of-attribution question is clearly in the negative, since here again a crucial factor determinative of such correctness will be the standards and meanings for the predicate among the relevant set of speakers, those the correctness of whose attributions is at issue. But this further factor is surely not determinative of which of us is actually tall; it is determinative rather of which of us is now truthfully and properly said to be "tall" (which in turn is distinct from the question of which of us is now truthfully and properly said to be tall.) 2. Lehrer's defense of coherentism relies on the idea that coherentism comports better with the nonsupervenience of the epistemic. And he believes this to be so in virtue of something else he believes: namely, that there is no "account" of the epistemic in nonepistemic terms. So far I have questioned whether nonsupervenience would indeed derive from such lack of an "account." Be that as it may, there is now this further question: Why should we suppose that no foundationalist status could be akin to coherence in failing to have any adequate "account" in nonepistemic terms? Take clarity and distinctness as the relevant foundationalist status. In fact, Descartes's proposal is in terms of enough clarity and distinctness. And, in any case, even if it is not Descartes's own, a foundationalist proposal could be defined in terms of enough clarity and distinctness. This would of course raise the question "Enough for what?"-to which the only acceptable answer might then be "Enough to give one certainty (or justification, or reasonableness, etc.)." Suppose, only for the sake of argument, that the indefinability in nonepistemic terms of the key epistemic status used by a theory (foundationalist or coherentist) would make that epistemic status independent (nonsupervenient). And suppose, again only for the sake of argument, that

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this would give that theory an advantage in competition with its rival theories of that epistemic status. In that case, it would seem that our foundationalism of enough clarity and distinctness would share the supposed advantages of coherentism. 3. Suppose, again only for the sake of argument, that coherence is inextricably epistemic, and, furthermore independent: that it does not supervene on the nonepistemic. And consider a foundationalist theory on which epistemic status does supervene on nonepistemic properties. Why should this give an advantage to coherent ism? If foundational justification is in fact supervenient, might this not give an advantage to foundationalism: namely, that it provides an account of epistemic justification, and of knowledge, and explains how these are supervenient on the nonepistemic? So long as the foundational account is able to do as well as the coherentist account in every other relevant respect, why should the coherentist account derive any advantage from the fact that it invokes only properties that are independent and not supervenient? Having thought hard about Lehrer's work for years, I was not about to stop doing so for this occasion. Thinking hard about something often leads to a lot of questions, of course, and much of the fun of philosophy is in the give and take of question and answer. I have tried to present my questions as starkly and clearly as I could, so as to avoid side issues and distracting qualifications. This does incur the risk of overlooking important subtleties. But if my questions are based on oversight or misunderstanding, they may at least elicit from Keith a fuller account of just how his anti supervenience argument for coherentism is supposed to go. It is an honor to have this opportunity to importune my friend, and I look forward to his response. 8

ENDNOTES I This paper originated as a talk in a Symposium in honor of Keith Lehrer held as part of the 2001 Pacific Division meetings of the American Philosophical Association. I remember meeting Keith at an APA "smoker," as they were called in the early sixties. Keith was then a professor in the legendary Wayne State department, I a graduate student at Pitt. Little did we know that our paths would cross so often in the years to follow, always to my benefit, as Keith realized his brilliant potential, with many publications on issues of main interest to us both, especially in epistemology. Though we started out far apart, over the ensuing decades our relevant views have converged steadily. To dwell on agreement would be boring, however, so here I will discuss one main remaining disagreement. 2 Self-Trust: A Study of Reason, Knowledge, and Autonomy (Oxford University Press, 1997), p. 62. 3 Ibid., p. 65. 4 Ibid., p. 67.

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5 Self- Trust, pp. 70-l. (, "Replies," in a book symposium on Self-Trust in Philosophy and Phenomenological Research 59 (1999): 1065-74; p. 1071. 7 On the question of supervenience there is a gulf between Lehrer and me. Already in "How Do You Know'?" (APO, 1974; reprinted in my Knowledge in Perspective), r am committed to the supervenience of the epistemic: Every case of knowledge by a subject S is said there to require a Tree of knowledge, such that: "Trees display true epistemic propositions concerning S and they also show what 'makes their propositions true' via epistemic principles .... A tree must do this for every epistemic proposition that constitutes one of its nodes. That is to say, trees contain no epistemic terminal nodes. It is in this sense that trees provide complete epistemic explanations .... " (KIP, p. 33.) 8 For illuminating discussion of epistemic supervenience and of Lehrer's views see James Van Cleve's "Epistemic Supervenience revisited," Philosophy and Phenomenological Research LIX (1999): 1049-1055, part of a PPR book symposium on Lehrer's Self-Trust, along with Lehrer's reply to Van Cleve on pp. 1069-1071. That in turn continues a conversation between the two of them over many years, continued first in Self-Trust, and then in the book symposium. My present paper joins that conversation, to which I had also been invited already in Lehrer's book.

Chapter 2 WHY NOT RELIABILISM? John Greco Fordham University

When I was a graduate student I would have gone to great lengths to talk with Keith Lehrer about epistemology. In fact, I did! Hearing that Lehrer would be talking at my alma mater, Georgetown University, I drove down to Washington D.C. from Providence, listened to his talk, and got myself invited to dinner. Much to the Georgetown students' horror, and probably Lehrer's as well, I proceeded to monopolize his time with my questions and commentary. (Sorry about that, Keith.) In any case, it is a great honor for me now to be invited to engage Lehrer more formally and more appropriately. I very much appreciate this opportunity. In his Theory ofKnowledge Lehrer tells us that his coherentist theory can be regarded as a form of reliabilism. 1 His reasoning is that, on his view, reliability is a necessary condition of both undefeated justification and knowledge. More specifically, personal justification requires that one accept both of the following principles: (T) I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true, and (TR) If! am trustworthy in what I accept, then I am reliable in obtaining truth and avoiding error in what I accept.

Moreover, undefeated justification and knowledge require that both of these acceptances be true. Hence undefeated justification and knowledge require reliability regarding what one accepts. (194) Notice that the reliability that Lehrer's view requires is reliability of the knower herself, as opposed to 31 E.1. Olsson (ed.), The Epistemology of Keith Lehrer, 31-41. © 2003 Kluwer Academic Publishers.

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reliability of her methods, or her evidence, or something else. Hence Lehrer's view is a version of what I have elsewhere called "agent reliabilism"; i.e., he requires that the knower herself, the cognitive agent, be reliable regarding what she accepts. 2 In this paper I want to raise the following question: Why isn't agent reliability enough? Or better, why does knowledge require, in addition to agent reliability, further conditions regarding coherence? In pursuing this question, I will consider what I take to be Lehrer's three most important arguments for thinking that agent reliability is not enough, and that therefore something further, such as coherence, is required. I will argue that none of Lehrer's arguments against a non-coherentist version of reliabilism is persuasive. Lehrer's three arguments can be summed up as follows. 1.

Knowledge has a functional role in science and in practical reasoning, and this functional role requires abilities involving articulation, reason-giving, and defense against objections. Hence the grounds of knowledge must be in an appropriate way available to the knower, as they are in a coherence theory.

2.

Externalism in general, and reliabilism in particular, are open to "the opacity objection." More specifically, they are open to counter-examples such as that ofMr. Truetemp, in which a) the person in question is reliable in what he accepts, but b) this reliability is opaque to him. Contra reliabilism, such persons lack knowledge. However, coherence removes opacity and thereby issues in knowledge.

3.

Gettier problems show that true reliable acceptance is not sufficient for knowledge. However, coherence requires further conditions, and these work so as to solve Gettier problems.

In the next section I will consider Lehrer's first argument rather briefly. I will then tum to the opacity objection in a more extended way. Here my argument will be this: Depending on how we interpret Lehrer's conditions for coherence, we must say either a) that Mr. Truetemp satisfies those conditions and therefore knows, or b) that in ordinary cases of perception, people do not satisfy those conditions and therefore do not know. If (a), then the counterexamples employed by the opacity objection fail to distinguish Lehrer's coherentism from non-coherentist versions of reliabilism. If (b), then Lehrer's coherentism has unacceptable skeptical results. I will end by considering Lehrer's treatment ofGettier problems. Here I will argue that a non-coherentist version of agent reliabilism can adopt a strategy very similar to Lehrer's.

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Lehrer has long endorsed a broadly Sellarsian theme: that knowledge properly so-called involves abilities to articulate and give one's reasons, and to defend one's knowledge and reasons against relevant objections. In the second edition of his Theory of Knowledge, for example, Lehrer writes: It is fundamental to the kind of human knowledge that concerns us in this book that it is inextricably woven into reasoning, justification, confirmation, and refutation. It is required both for the ratiocination of theoretical speculation in science and practical sagacity in everyday life. To do science-to engage in experimental inquiry and scientific ratiocination-one must be able to tell whether one has correct information or not.. .. Engaging in law or commerce requires the same sort of knowledge, which may be used as the premises of critical reflection or claimed as the prizes of informed reasoning. (6)

This same theme is the basis for objections to both foundationalism and externalism. Thus Lehrer objects to a foundationalist account of perceptual beliefs on the following grounds: Perceptual beliefs are considered innocent until proven guilty when we care not the least whether the belief is innocent or guilty. Once we do care, though, we start to ask serious questions, the ones concerning justification .... We seek to determine if the person has information that would enable him to determine whether he actually sees the thing he thinks he does and render him justified. (74)

A similar objection is lodged against externalism. As in our refutation offoundationalism, what is missing from the accounts of externalists is the needed supplementation of background information and the transparency of it.... Such information is what is needed to supplement the information contained in the belief alone, and it is precisely the sort of information required for coherence and irrefutable justification. (185-6)

The reasoning behind these objections can be reconstructed as follows. First, knowledge plays an essential role in scientific inquiry and practical wisdom, which role makes knowledge "inextricably woven into reasoning, justification, confirmation, and refutation." But these, in turn, issue in the

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requirement of relevant background information. In other words, such background information is needed to make possible the knowledge-related practices of reasoning, justification, confirmation, and refutation. This sounds reasonable enough, but it raises the question of psychological plausibility. Namely, is it plausible that we typically have the background information that is required? For example, do we typically have relevant information about our perceptual faculties, the circumstances in which they are reliable, and whether we are presently situated in such circumstances? Lehrer's answer to the psychological plausibility objection is to understand background information in terms of acceptances, and to understand acceptances in terms of their functional role in reasoning, confirmation, etc. 3 Hence, for S to accept that her perceptual faculties are reliable in present circumstances does not require that she explicitly judges that this is so. Rather, it requires only that S act in certain ways when in certain circumstances. But can we think of this sort of implicit acceptance as background information, as we would have to for it to be relevant to coherence and justification? Lehrer's answer is yes: A person may be said to have information he cannot easily describe and to employ such information in various ways. For example, suppose I know the shortest route from Rochester to Buffalo, though I cannot tell you the name of the highway. Moreover, imagine that I am not very good at giving directions, so I cannot tell you how to get from Rochester to Buffalo .... That I make the trip successfully on many occasions shows that I have the required information, which I might find difficult to articulate, about the route from Rochester to Buffalo. Similarly, my reliability in accepting that I see when I do, or even in accepting that I feel or think when I do, depends on my ability to employ information, which I might find difficult to articulate, about seeing, feeling, and thinking. (74-5)

The problem is now this: The present objection to externalism, and the motivation for turning to a coherentist version of reliabilism, is that knowledge requires background information for the purposes of reasoning, justification, confirmation, and refutation. But now, it turns out, the background information that coherence provides need not be available for use in these activities. It would seem that Sellarsian themes regarding the role of knowledge in science and practical wisdom cannot be used to motivate Lehrer's coherentism over noncoherentist reliabilism.

2. THE OPACITY OBJECTION TO RELIABILISM. The opacity objection to externalism in general and to reliabilism in particular is as follows.

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There is, however, a general objection to all externalist theories that is as simple to state as it is fundamental: the external relationship might be opaque to the subject, who has no idea that her beliefs are produced, caused, or causally sustained by a reliable belief-forming process or properly functioning cogntive faculty .... All externalist theories share a common defect, to wit, that they provide accounts of the possession of information, which may be opaque to the subject, rather than of the attainment of transparent knowledge. (185)

The opacity objection is illustrated by the case ofMr. Trutemp. Suppose a person, Mr. Truetemp, undergoes brain surgery by an experimental surgeon who invents a small device that is both a very accurate thermometer and a computational device capable of generating thoughts .... Assume that the tempucomp is very reliable, and so his thoughts are correct temperature thoughts. All told, this is a reliable belief-forming process and a properly functioning cognitive faculty. Now imagine, finally, that Mr. Truetemp has no idea that the tempucomp has been inserted in his brain and is only slightly puzzled about why he thinks so obsessively about the temperature; but he never checks a thermometer to determine whether these thoughts about the temperature are correct. He accepts them unrefiectively, another effect of the tempucomp. Thus, he thinks and accepts that the temperature is 104 degrees. It is. Does he know that it is? Surely not. He has no idea whether he or his thoughts about the temperature are reliable. (187)

The example ofMr. Truetemp is supposed to serve as a counter-example to reliabilism. More specifically, it is supposed to be a counterexample to noncoherentist versions of reliabilism. The idea is that Mr. Truetemp does not know, although he does fulfill the conditions for knowledge set down by noncoherentist reliabilism. However, the example does not serve Lehrer's purposes unless some other things are true as well. First, it must be the case that Mr. Truetemp does not know on the conditions for knowledge set down by Lehrer's coherentist theory. Otherwise, the Truetemp example will not distinguish noncoherentist reliabilism from coherentist reliabilism. Furthermore, it cannot be the case that Lehrer's theory is overly restrictive, so that it turns out that, on his view, there is no knowledge even in ordinary cases of perception. Otherwise, the fact that Lehrer's theory rules that Mr. Truetemp does not know will not indicate a virtue of his theory. Accordingly, for the Truetemp example to work for Lehrer against non-coherentist reliabilism, all of the following three conditions must be fulfilled: 1.

Mr. Truetemp knows on non-coherentist reliabilism,

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Mr. Truetemp does not know on Lehrer's coherentist reliabilism, and

3.

Ordinary cases of perception count as knowledge on Lehrer's coherentist reliabilism.

I will now argue that there is no way to interpret Lehrer's theory so that all of these conditions are fulfilled. More specifically, on some interpretations of Lehrer's theory, Mr. Truetemp knows. On other interpretations, ordinary cases of perception do not count as knowledge. First, it is not clear why Mr. Truetemp does not know on Lehrer's account. Specifically, it is not clear why Truetemp is not in the same position, vis-a.-vis coherence, as knowers are in ordinary cases. Consider, for example, Lehrer's remarks concerning knowledge and skepticism. Although we thank the skeptic for reminding us that...we sometimes err and are ever fallible in our judgment, we may at the same time neutralize her objection .... The objection based on our fallibility is neutralized by our trustworthiness. It is as reasonable to accept both that we are fallible and that we are trustworthy in a truth-connected way as it is to accept only that we are fallible. (220) In general, Lehrer thinks, we can invoke our trustworthiness to reason that some acceptance is reasonable. A consequence of adding principle (T) to my evaluation system is that I may reason from it and the acceptance of some target acceptance that p to the conclusion that the target acceptance is reasonable. My reasoning would be as follows. T. I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true. I accept that p with the objective of accepting that p just in case it is true. Therefore, I am trustworthy in accepting that p with the objective of accepting that p just in case it is true. Therefore, I am reasonable in accepting that p with the objective of accepting that p just in case it is true.

The argument from trustworthiness to reasonableness, which I shall refer to as the trustworthiness argument, assumes that my trustworthiness may explain why it is reasonable for me to accept what I do. (139)

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The relevant question is, why can't Mr. Truetemp reason in exactly the same way? Put differently, why isn't the reasonableness of Mr. Truetemp's acceptance about the temperature explained in exactly the same way? Moreover, why can't Mr. Truetemp invoke principle (TR) to reason even further, and to conclude that his acceptances about the temperature are not only trustworthy, but reliable? Again, consider how, according to Lehrer, the dialectic with the skeptic proceeds in ordinary cases. Critic (or skeptic): Let us admit that your are intellectually trustworthy and intellectually virtuous, as you claim. You are, nevertheless, in error because such trustworthiness and virtue fail to achieve their purpose. What you accept in this trustworthy and virtuous way is not reliably connected with the truth .... What should the claimant reply? The reply must be that the critic or skeptic is wrong! ...

Claimant: What I accept in this trustworthy and virtuous way is reliably connected with truth in a successful way. The way of virtue is also the way of truth. (211-2)

Again, why can't Mr. Truetemp follow the same dialectic? If he can, then Truetemp knows on Lehrer's account, and so the Truetemp case does not distinguish non-coherentist reliabilism from Lehrer's coherentism. I assume that Lehrer thinks that Mr. Truetemp cannot follow the same dialectic. However, it is not clear why. One reason that suggests itself is that Mr. Truetemp accepts his thoughts about the temperature "unreflectively." But what does this mean? One thing it might mean is that Truetemp has no further acceptances regarding his trustworthiness and reliability in this regard, and so does not have the requisite materials in his evaluation system to sustain a relevant dialectic. However, it is not at all clear that Mr. Truetemp does not have the relevant acceptances in his system. Remember, Lehrer defines acceptances in terms of their functionality in action and thought. But according to the example, Mr. Truetemp does act and think as if he thinks that he is trustworthy and reliable regarding his ability to determine the temperature. He acts and thinks more or less the way that normal people do regarding their ability to determine simple mathematical truths, or regarding their ability to determine colors in good light. That is, he acts and thinks as if he thinks that he is trustworthy and reliable, although he makes no conscious judgements in this regard. Moreover, Mr. Truetemp is reliable in the relevant regard, and therefore his acceptances are true and convert personal justification to undefeated justification and knowledge.

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Lehrer might object that Mr. Truetemp cannot explain his ability to tell the temperature in any detailed way; i.e. in a way more specific than referring to principles (T) and (TR). But neither could most people defend their ability to tell colors in any detailed way. Most people, I assume, would simply insist that they can tell, or else very quickly get into a quite inadequate (and probably false) explanation as to how they can tell. Let me be clear: The point I am making here is not that Mr. Truetemp knows. On the contrary, I think that he does not know, and below I will offer my own explanation regarding why he does not know. My point, rather, is that Lehrer's coherence theory is faced with the dilemma set out above. Depending on how one interprets Lehrer's conditions for coherence and knowledge, either a) Truetemp has the requisite true acceptances in his evaluation system, in which case he knows, or b) he does not, in which case neither do ordinary perceivers, and so they don't know. Let us consider one more reply on Lehrer's behalf, however. Lehrer might argue that there are true objections (or competitors) in the Truetemp case, which defeat Truetemp's personal justification, and which are not present in cases of ordinary perception. For example, Lehrer might argue, Truetemp cannot answer the following objecton: (0) Someone has implanted a device in your brain, and that is why you believe what you do about the temperature. Notice, however, that (0) is misleading: (0) counts as an objection on Lehrer's view, since it is less reasonable for Truetemp to accept what he does about the temperature on the assumption that (0) is true than it is on the assumption that (0) is false on the basis ofTruetemp's evaluation system. However, Truetemp is perfectly reliable in matters regarding the temperature, and so the objection is misleading insofar as it suggests a reason against Truetemp's belief. But now consider that there will also be misleading objections available against S's acceptances in ordinary cases of perception. For example: (0') You are reliable in your perceptual beliefs in conditions C but not C', and it is possible that you are presently in conditions C'. Or consider: (0") There are experts in philosophy and science who believe that apples are not red and that the sky is not blue. How are these sorts of objections to be answered in ordinary cases of perception? Why should we think that such objections always can be answered? For example, consider that C' in (0') might describe conditions about which S is wholly ignorant, or perhaps conditions that S lacks the conceptual capacities even to consider. Similarly, S might have no idea why anyone would accept that (0") is true, and no idea how to reply to such considerations if she did have an idea of them. Perhaps S can neutralize (0') and (0") by referring to principle (T) and/or principle (TR) above. Or maybe she can neutralize the objections in some other way. But if she can, why can't Mr. Truetemp neutralize (0) in the same way? Again, depending on how Lehrer's theory is supposed to handle

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misleading objections, it would seem that either a) Truetemp has the requisite true acceptances in his evaluation system to neutralize such objections, in which case he knows, or b) he does not, in which case neither do ordinary perceivers, and so they don't know. Either way, the Truetemp case does not serve Lehrer's purposes in the opacity objection against externalism and reliabilism.

3.

GETTlER PROBLEMS

I now turn to Lehrer's third argument against non-coherentist reliabilism: that true reliable acceptance is not sufficient for knowledge. Another equally important reason why reliabilism will not suffice [for the sort ofjustification required for knowledge] is that global reliability might be irrelevant locally. Consider again the case of Mr. Goodsumer, who sums reliably but not in the particular case. He is not trustworthy in the way he sums in this case. Trustworthiness must be connected with truth in order for personal justification to convert to knowledge in the particular case. (224)

What is the nature ofthe required connection? What does it mean to say that trustworthiness in what one accepts is successfully connected with truth in what one accepts in the particular case? It cannot mean, as we have noted in the case of Goodsumer, that being trustworthy in what one accepts is generally or reliably successful. It means that the person is successful in accepting what is true because she accepts what she does in a trustworthy way in the particular case. Her trustworthiness explains her success in accepting what is true .... Her trustworthiness and the reliability of it explains her success in the particular case. (223)

This is a very nice idea. In Gettier cases, the person has true acceptance but it is only a matter of luck that the acceptance is true. In cases of knowledge, the person has true acceptance because she is trustworthy (or virtuous) in the way that she accepts what she does. This idea does not give the advantage to coherentism over non-coherentist reliabilism, however, because the reliabilist can say the same thing. More specifically, the agent reliabilist can say the same thing: in cases of knowledge, S accepts what is true because she is reliable. 4 This move is particularly attractive from the perspective of agent reliabilism, since in general credit is closely tied to agent reliability. For example, we give an athlete credit when we think that she accomplishes her feat because she has great abilities. According to Aristotle, actions deserving moral credit "proceed from a firm and unchangeable character."s The present

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suggestion is that knowledge involves a kind of intellectual credit. In cases of knowledge, it is to S's credit that she accepts what is true; i.e. she accepts what is true because she is reliable in the relevant way. Finally, the present perspective gives us an explanation as to why Mr. Truetemp does not know. Namely, the tempucomp in Truetemp's brain undermines the notion that he accepts the truth because he is reliable. In other words, it is not to Truetemp's credit that he accepts the truth. Consider the following remarks by Joel Feinberg, concerning the requirements for moral credit. should like to suggest that the more important to a full and comprehensive understanding of a triggered action the actor's own dispositions and thresholds are, the more likely we are to consider the act truly his, provided that those dispositions and thresholds are not biologically or psychologically abnormal and that they were not imposed on him by manipulation. 6

In other words, we do not consider Truetemp's acceptances about the temperature to be truly his, in the sense required for intellectual credit, precisely because they are the result of dispositions and thresholds that are "biologically and psychologically abnormal" and "imposed on him by manipulation." Truetemp accepts the truth because the tempucomp is reliable, not because he is reliable. 7 Hence agent reliabilism can endorse Lehrer's strategy for solving Gettier problems, and can place this strategy within a general theory of credit. Moreover, this strategy gives agent reliabilism resources for explain ing why Mr. Truetemp does not know. None of this has anything to do with coherentism, however. I conclude, then, that Lehrer does not give us good reasons to prefer coherentism to non-coherentist versions of agent reliabilism. 8

ENDNOTES IKeith Lehrer, Theory 0/ Knowledge, 2nd edition (Boulder, CO: Westview Press, 2000), p. 172. Below, all page numbers in the text refer to this volume. 2. See my "Agent Reliabilism," Philosophical Perspectives. J3, Epistemology, James Tomberlin, ed. (Atascadero. CA: Ridgeview Press, 1999); and Putting Skeptics in Their Place (Cambridge: Cambridge University Press, 2000). 3. See Lehrer's "Replies" in The Current State 0/ the Coherence Theory, John Bender, ed. (Dordrecht: Kluwer Academic Publishers, 1989); and Theory o/Knowledge, esp. pp. 39-40. 4. I argue for this account ofknowledge in "Knowledge as Credit for True Belief," in Intellectual Virtue. Perspectives from Ethics and Epistemology, Michael DePaul and Linda Zagzebski, eds. (Oxford: Oxford University Press, 2002).

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Nicomachean Ethics, II.4. Joel Feinberg suggests that all attributions of moral credit imply that the action in question proceeds from character. This is probably too strong. Nevertheless, there is a special sort of moral credit, with which Aristotle is concerned, that does imply this. See .Toe I Feinberg, DOing and Deserving: Essays in the Theory of Responsibility (Princeton: Princeton University Press, 1970), p. 126. 6. Doing and Deserving, p. 171. Emphasis added. 7 More needs to be said, of course. I try to say some of it in "Knowledge as Credit for True Belief." On my own view, abnormality and manipulation do not always undermine positive epistemic status. But they do in cases where they undermine credit. x. I would like to thank Keith Lehrer and Ernest Sosa for helpful conversations on relevant issues. 5.

Chapter 3 JUSTIFICATION AND PROPER BASING' Jonathan L. Kvanvig University of Missouri

Some thirty or so years ago, Keith Lehrer attacked the idea that causation has much to do with knowledge or justification with the case of the gypsy lawyer, and has more recently endorsed the same kind of attack with the case of the racist scientist. 2 These cases threaten not only causal theories of knowledge but also theories of knowledge or justification which require that one's evidence be at least a partial cause of one's belief. They threaten, that is, the view that causation is at the heart of the distinction between propositional justification, the justification one has for the content of one's belief, and doxastic justification, the justification which attaches to the believing itself. When justification attaches to the believing itself rather than merely to the content of what is believed, it is because one holds the belief in question on the basis of the evidence. When justification only attaches to propositional contents, there is a failure of such basing, e.g., one may have the evidence but believe for different reasons. This distinction is important for at least two reasons. First, only doxastically justified beliefs are candidates for knowledge, on any theory which requires justification for knowledge. Propositional justification is a step in the right direction, but if one's believing itself is not justified, one cannot have met the justificatory requirements for knowledge. Second, only doxastically justified beliefs satisfy any purely intellectual requirement to believe claims that are justified, for any such requirement will surely include the requirement that we hold such beliefs for the right reason, i.e., on the basis of that which justifies them. So a proper account of the distinction between doxastic and propositional justification is important for a complete theory of justification and for a complete theory of knowledge. 43 E.J. Olsson (ed.). The Epistemology of Keith Lehrer, 43-62. © 2003 Kluwer Academic Publishers.

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Though Lehrer's arguments played a role in the abandonment of causal theories of knowledge, the epistemological community has not endorsed his view that a causal account of the basing relation is defective. In some cases, epistemologists have simply found Lehrer's examples unpersuasive,3 and in other cases, they have argued against the conclusion Lehrer draws from his examples. I want to look at this issue here, for I think that there is more to be said on behalf of Lehrer's view than has been appreciated. Causality is ubiquitous in nearly all of our experience of the world, but it is not conceptually involved in the concepts of knowledge or justification. In particular, Lehrer is right that the basing relation is not a species of causal relation. A terminological point is in order before beginning. There is a sense in which, when someone denies that evidence needs to be causally responsible for belief in order for it to be doxastically justified or to count as knowledge, that person is denying that belief needs to be based on that evidence. After all, in such cases, belief is not causally grounded in, nor explained by, awareness of the evidence. That is not the concept of basing that is relevant here, however. What is central here is the distinction between propositional and doxastic justification. Two jurors, for example, can be presented with precisely the same evidence and both believe the defendant is innocent. One might believe this claim by attending to the evidence, and the other because his horoscope said, "you will need courage today to make a negative judgment about a very bad person." In the second case, the juror does not attend to the evidence or even consider the question of whether the evidence confirms the guilt of the defendant. He hears the evidence and forms beliefs about it, but this experience is not connected at all with his belief. So, whereas the first juror is doxastically justified and may know, on the basis of the evidence, that the defendant is guilty, the secondjuror only has propositional justification and fails to know on the basis of the evidence that the defendant is guilty. The concept of basing that is relevant here is that concept central to this distinction. Even ifthere are other concepts of basing on which a person can be said to know without basing belief on evidence (because the evidence doesn't cause the belief), the concept of concern here is that concept in virtue of which we distinguish candidates for knowledge in terms of whether the person has doxastic or merely propositional justification for belief.

1.

LEHRER'S EXAMPLES

We can begin with Lehrer's examples. The first case concerns a gypsy lawyer of a client accused of eight murders. The lawyer consults the Tarot cards, and they say that the client is guilty of committing all but the eighth murder. The lawyer believes what the cards say, and his conviction of the innocence of his client regarding the eighth murder leads him to reconsider the

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evidence, which he now comes to see conclusively establishes that his client is innocent of the eighth murder. Lehrer then goes on to claim: He freely admits, however, that the evidence which he claims shows that he knows his client to be innocent of that crime is not what convinced him of the innocence of his client, and, indeed, would not convince him now were he not already convinced by the cards ... His conviction could not be increased by his consideration of the evidence because he was already completely convinced. On the other hand, were his faith in the cards to collapse, then emotional factors which influence others would sway him too. Therefore the evidence which completely justifies his belief does not explain why he believes as he does, his faith in the cards explains that, and the evidence in no way supports ... or partially explains why he believes as he does. 4 Lehrer thus claims that the lawyer knows that his client is innocent even though the evidence which justifies his belief does not either prompt his original acquisition of the belief, nor does the evidence lend increased confidence in the belief once it is discovered, nor does the evidence at present sustain the belief. This last point is true in virtue of the fact that, if the influence of the cards were removed, emotional factors would hold sway and the lawyer would no longer believe that his client was innocent. Nonetheless the lawyer now knows and justifiably believes that his client is innocent of the eighth murder. More recently, Lehrer has forwarded the case of Ms. Prejudice: Imagine the case of Ms. Prejudice, who out of prejudice against a race believes that the members of the race who have a certain disease get the disease because of their genetic makeup. Of course, she, being very racist, believes this is a sign oftheir racial inferiority, and she is totally convinced because of her racism that the disease is the result of the genetic constitution of the race. Now imagine that Ms. Prejudice becomes a medical student and learns, to her pleasure, of the medical evidence that supports her prejudiced conviction. She becomes, however, a medical expert of the highest quality, fully capable of separating her prejudices from her scientific studies. As luck would have it, she becomes part of a research team assigned the task of checking on the genetic basis of the disease .... She wants to make sure it [the disease] really is [genetically caused], and she will force them [her co-investigators] to investigate with the greatest care every reason for doubting that the disease is genetically caused. She wants to make absolutely sure that she cannot be charged with concluding on the basis of the scientific evidence that the disease is genetically caused because of prejudice. Of course, her belief that the disease is genetically caused is the result of her still very intense prejudice, but her scientific evaluation ofthe evidence in favor of this belief must be rigorously tested.

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JUSTIFICATION AND PROPER BASING Every objection to the claim is considered and refuted by the team, all of whom, except for Ms. Prejudice, who plays devil's advocate, are completely without prejudice. They all conclude that the scientific evidence shows conclusively that the disease is genetically caused, as Ms. Prejudice has believed all along. After the investigation, she knows that the disease is genetically caused. She has the same evidence ... for believing this as the other members of her team, and if they know that the disease is genetically caused, so does she. But her belief is the product of an improperly functioning system of racial prejudice. 5

Just as in the case of the gypsy lawyer, the racist scientist initially comes to a belief on the basis of suspect motivations. According to Lehrer, these motivations remain the basis for the belief even after learning of the evidence that confirms the belief. Still, Lehrer claims, the racist scientist has knowledge (and, by implication, justification) if her colleagues do. After all, they have worked on the project together, knowing the intellectual character and prejudices of each member of the team. It is obvious that, if asked who on the team knows and who doesn't, they'd be perplexed at the idea of having to draw such a distinction. They'd surely say that either everyone knows or no one does. Since I will be focusing on the issue of the proper construal ofthe basing relation, it will be useful to recast the discussion in terms of it. The lawyer and the scientist each have adequate evidence for thinking what they do, but they do not initially base their beliefs on that evidence. Later on, each comes to see that the evidence confirms their belief, even though the evidence is not even a partial cause of their beliefs. Since there is nonetheless a distinction between merely having sufficient evidence for a belief and having that evidence justifY one's believing of the claim in question, we can characterize the two cases as follows. The lawyer and the scientist come to be doxastically justified in believing what they were originally not doxastically justified in believing, and this claim implies that they satisfY whatever basing relation between evidence and belief is appropriate for capturing the distinction between doxastic justification and propositional justification. Their beliefs are nonetheless not caused, not even partially, by their awareness of the evidence; their deficient intellectual characters result in still-true regrettable causal stories about their beliefs. Thus, if we accept Lehrer's account, a causal account of the basing relation is mistaken.

2.

AUDI'S DEFENSE

Causal theorists have gone in two different directions in response to such cases. Some have admitted the existence of knowledge and proper basing after

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investigation by the principals involved, and have attempted to save the heart of the causal theory by giving up the claim that any actual causal relations are required. Instead, they have attempted to salvage some causality in knowledge by finding a true counterfactual involving a causal relation between evidence and belief which is true and hence is compatible with these admissions, claiming that this causality-embedded counterfactual is necessary for knowledge. 6 I have argued against such theories elsewhere/ but will bypass the issues involved here. For such emendations of a causal requirement on the basing relation do not amount to a defense of a causal theory of basing. Instead, they agree with Lehrer that a causal requirement is mistaken, so they pose no threat to the conclusion Lehrer wishes to draw from his examples. The other direction is to argue against the claim that the players in Lehrer's examples come to have doxastically justified beliefs and hence against the claim that they have knowledge. Robert Audi presents the only sustained defense in the literature of this position, and his discussion focuses on the case of the gypsy lawyer. He says, Let us first consider some consequences of Lehrer's interpretation of the example. Recall the assumption that the cards are not actually relevant to p. Thus, even though S (here the gypsy) has (objectively) good evidence for p, given a contrary verdict from the cards he would (other things equal) have had the false belief that not-po Second, given his faith in the cards, he would have believed p even if it had been false, indeed, even if, on the basis of the cards, it had not been rendered so much as objectively likely (to any degree) to be true, i.e., very roughly, likely to some degree given the actual facts relevant to p... Third, S would have believed other falsehoods about the crime, had the cards pointed to them, e.g., that the client's spouse committed it. These points, especially the second, strongly suggest that S does not justifiably believe p. It is, after all, simply good fortune (because the cards happened to be right) that S did not believe something false in place of p. Surely if one's belief that p is justified by good evidence, it cannot be simply good fortune that one did not believe something false instead. 8 Audi here worries about a certain sort of epistemic luck in believing a proposition. This sort of luck is present when one is indiscriminate with respect to the truth. In the case of the lawyer, his reliance on the cards makes him indiscriminate with respect to the claim that his client is innocent. As Audi claims, "given his faith in the cards, he would have believed p even if it had been false, indeed, even if, on the basis of the cards, it had not been rendered so much as objectively likely (to any degree) to be true." This feature of the gypsy lawyer case runs counter to what Audi sees as a reliable indicator connection established by the presence of personal justification. That connection is that

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personal justification implies that if the proposition in question were not true, the person in question would not believe it. Audi thus claims that because the lawyer's belief is just a matter of this sort of epistemic luck, or "good fortune" as he puts it, it is wrong to think that the lawyer really knows, or justifiably believes, that his client is innocent of the eighth murder. Audi seems to recognize some weakness in this defense of the causal requirement, however. Consider his formulation of the reliable indicator connection: [T]here is also an important (and far less widely recognized) connection between personal justification and truth. The latter connection is our main concern here. In the most common cases where Ss belief that p is justified by good evidence, q, S would not have believed p if p were not true or at least objectively likely to be true. For here S would not have believed p ifhe had not believed q, in virtue of which-since q is (objectively) good evidence for p-p is at least objectively likely. There is, I suggest, a measure of protection from believing falsehoods which justification by good evidence provides. 9

Audi claims that there is a connection between personal justification (what I have been calling doxastic justification) and a measure of protection from believing falsehoods. The protection arises from the reliable indicator requirement, to the effect that if the claim had not been true, the person in question would not have believed it. This protective clause is supposed to support a rejection of Lehrer's account of his examples, but notice that Audi does not give a complete endorsement of the clause. Rather, he claims that the requirement holds "in the most common cases ... " A response on behalf of Lehrer is easy if this qualifier is taken seriously, for gypsy lawyer cases need not be all that common in order to undermine the causal view. If it is granted that the reliable indicator connection only holds in the most common cases, however, it is not clear how the reliable indicator connection can form a strong enough reason for maintaining that there is an exceptionless causal sustaining requirement. Yet that is just the structure of Audi's argument: he holds that there is a reliable indicator connection which holds in the most common cases and uses this information to conclude that there is an exceptionless causal sustaining requirement. That argument is not telling against Lehrer's view, for it would be at least as plausible to conclude from Audi's premise that there is a causal sustenance element in the most common cases of knowledge. Furthermore, Audi's worries about the presence of luck are not telling, either. It is well-known that it takes a cooperative environment for knowledge to occur. Think, for example of Goldman's fake barn case, in which the residents of a certain area undermine our claim to knowledge by planting a huge

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number offake barns in a landscape in which we happen to focus on the one real barn. Suppose, though, that they were only giddily considering the fun they'd have doing so, but decide at the last minute not to play such ajoke on us. We'd have knowledge in such a case, but be lucky to have it. Or suppose that they decide to play the joke on us, but we serendipitously happen to take a different road and happen to look at a different landscape with no fake barns on it. Perhaps a black cat crossed the road, and our superstitions led us to turn to the right rather than the left in order to avoid the horror of having the cat cross the fork in the road that we traveled. Then we'd still have knowledge, but be lucky to have it. Audi might insist that these are not the kinds of luck that knowledge rules out, whereas the kind he is speaking of is that kind. To defend such a position, we would need an account of the distinction between these two kinds of luck, and Audi recognizes that no such account will be forthcoming by appeal to the reliable indicator connection (since it can only be said to hold in the most common cases). In addition, progress on the dispute between Audi and Lehrer is not going to be made by relying on some delineation of the various kinds of luck that might infect belief. As I see it, the only way to determine what kind of luck knowledge rules out is to forward an acceptable account of knowledge, and then classify instances ofluck in terms of that account. That is, I see no grounds for thinking that we could sort instances of luck into kinds apart from our interest in the nature of knowledge, and have one of these kinds be just the right kind to solve the Gettier problem. In the absence of the plausibility of this approach to the Gettier problem, appeals to the concept of luck will end up as unconvincing as relevant alternative responses to skepticism, which claim that skepticism is false because one need only be immune from error in relevant alternatives, among which are not found skeptical alternatives. For these reasons, Audi's arguments based on the concepts ofluck and reliable indication against Lehrer's examples must be determined to be unsuccessful.

3.

A GENERAL APPROACH TO JUSTIFICATION

In terms of persuading the reader to accept the alternative conclusion that a causal theory of the basing relation is mistaken, the discussion to this point has done little more than the presentation of the gypsy lawyer case itself would have done. We have seen that the arguments against Lehrer's examples are unconvincing, but it remains the case that this example has not moved many to reject causal accounts. It seems, then, that some further argument would be useful, and I believe there is a strong argument to buttress Lehrer's examples from the general nature of justification. I say "general nature," because justification is not only a property of beliefs but also of actions. It is plausible,

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therefore, to assume that a proper account of justified beliefwill be extendable to an account of justified behavior. I want to argue that a theoretically unified approach to the concept of justification, one that attends not only to the nature of justification as a feature of belief but also to its nature as a feature of action, provides a strong argument against a causal view of the basing relation. In the arena of action, the causal view maintains that there is a distinction between reasons which only justify the action performed and reasons which justify the performance of the action. On the causal view, if the reasons are causally responsible (in the right way) for the action in question, then those reasons justify the performance of the action as well as the action itself; otherwise they can only justify the action itself. In this way, the causal account of rational action claims to have explained the difference between a sort of personal justification, where the performance of an action is justified, and a more impersonal justification, where only the action performed, but not the performing of it, is justified. This distinction mirrors the distinction we have in the arena of belief between propositional justification and doxastic justification. I believe this causal view is not adequate and I shall argue that it cannot make sense of one feature of justification. Most of us discover, at one time or another, that our motivations for behavior are less than desirable. I shall argue that one response to this awareness, a response in which justification is created where it did not exist before, is one for which the causal view cannot account. Let us begin by considering a bit of behavior which is to be assumed to lack full justification. Suppose Jim is running for Congress, where this behavior is to be explained by an irrational desire to prove his critics wrong. This desire arose because, being from the hill country in Texas, he believes that people make fun of him and ridicule him because there is no possibility of his ever "amounting to much." As a matter of fact, Jim has no reason to believe this and is just showing paranoid tendencies, but he does hold the beliefs in question and because he does, he forms the desire to prove his critics wrong. So, Jim is running for Congress to show that he has amounted to something. Regardless of how common or understandable such motivations are, they present an explanation for Jim's actions which does not amount to ajustification of them. Whatever reasons there might be which could justify Jim's running for Congress, this irrational desire to prove his critics wrong (irrational because his beliefthat there are such critics is unfounded) is not among them. Further, suppose that Jim has not detected his real motivations and that he has given reasons both to himself and others for running which have been quite different from the "real" reasons for which he runs. But now, having advanced in years and self-understanding, Jim has come to realize his true motives. He has come to realize that the reasons he has given for running are not what brings him to run for Congress.

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In evaluating the plausibility of this causal view, I will be employing two kinds of claims as a guide to which causal connections exist in a given case. First, I will employ counterfactuals. One theory of causation is a counterfactual theory, on which to say that one event or state is the cause of another is to say (roughly) that, were the first event or state absent, the second would be absent as well. 10 There are many problems with this theory of causation, II one ofwhich is especially pertinent here. For, at most, the counterfactual theory of causation is only adequate for deterministic causation, and is wholly implausible regarding probabilistic causality. In order to address this concern, I will also look at the issue of probability enhancement by proposed causal factors, in addition to the counterfactuals to be examined. In each case, I do not presume that the concept of causality can be analyzed or explicated in terms of these notions. I only presuppose that the existence or lack of such is good evidence regarding the existence of causal connections. In the case we are considering, we have sufficient evidence for thinking that Jim's running for Congress is the result of his irrational desire because, if Jim's irrational desire were absent, he would quit the campaign. Perhaps he would become a beach bum instead. When Jim's self-awareness increases, Jim comes to realize thatthe reasons he has been offering for his behavior (i) did not originally prompt the behavior, (ii) have not, in the past, sustained the behavior, and (iii) do not now sustain the behavior. Regarding this third fact, what Jim realizes is that he is so constituted at present that the reasons he has offered do not even enhance the probability of his running, even if we were to control for the causal force of his irrational desire. Upon confronting these rather disturbing facts, Jim then reasons as follows: "the inadequate motivations both past and present are regrettable and everything possible ought to be done to alter them; but, until this alteration can be accomplished, everything possible ought to be done to maintain some motivation or other to keep running for Congress since, after all, it is nonetheless true that I am extraordinarily good at convincing others of correct policy, that I am best qualified to serve the constituents of this district, and if persons were to attempt to quit doing everything which is done for inadequate reasons, not (as) much good would be done." So, Jim concludes, he ought to do all in his power to keep the race for Congress alive in spite of his bad motivations. There is an epistemic fact about Jim which needs to be explained by a satisfactory account of justification. How to express this fact is a bit troublesome, but we might try to put the point as follows. Jim has made progress of a purely theoretical sort toward the goal of being perfectly rational, of achieving the justificatory ideal. He has achieved a level of coherence between thought and action which, though not ideal, is closer to the ideal than what his prior self had achieved, first in ignorance of his true motivations and next in a quandary about what to make of the tension between his behavior and

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his awareness of his inadequate motivations. The fact which must be explained is this progress. The explanation I will argue for is that the progress achieved is that sort attaching to the performance of the action in question which, when it obtains, justifies the performance of that action. Of course, this explanation cannot be employed by the causal theory, because the reasoning process above does not have any causal impact on the particular behavior with which we are concerned. Call the reasoning process in question "R". The occurrence of R is compatible with the following truths: (a) if Jim did not have his irrational desire, he would no longer be running for Congress; (b) even if R had not occurred, Jim would still be running for Congress; and (c) if R had occurred and Jim's irrational desire disappeared, Jim would no longer run for Congress. Moreover, if we were to find a way to control for the effect of Jim's irrational desire, R would have no probabilistic effect on Jim's behavior. Surely it is reasonable to assume that R will affect his overall behavior at some point, for that is exactly what the reasoning process shows Jim's intentions to be; but it need not have any immediate causal impact on his running for Congress. We might capture this point by calling the reasoning process a meta-motivational or meta-causal reasoning process. If the reasoning process is a motivational one, i.e., if it is even minimally causally efficacious with respect to the action in question, it would be quite confused; for it includes the recognition that Jim cannot, simply by willing it or thinking about it, alter his motivation at present. I shall assume, though, that Jim is not so confused. What needs to be explained, to repeat, is the progress Jim makes in the above case. What I shall argue is that any of the explanations open to a causal theory do not sufficiently explain this progress, and thus that the causal theory is shown to be inadequate by cases involving meta-motivational reasoning processes. In order to defend these claims, we need some understanding of the components of the justificatory ideal so we will be able to ascertain the variety of alternative explanations open to the causal theory. This ideal requires, first, that all actions, beliefs, desires, intentions, etc., be fully justified, i.e., all actions be justified ones to perform, and all mental states be justified states in which to be. Further, it requires that one justifiably perform all of one's actions, and justifiably be in all the relevant mental states in question. Finally, this ideal requires that the person in question have certain character traits which I shall refer to loosely using the notion of being fully rational. The first two requirements of the ideal relate, first, to the actions and states themselves, and then to the relation between the person and the actions and states. This final requirement relates to the person alone: he/she must be fully, or ideally, rational as well. So, we are looking for an explanation in one of these three areas for the progress that Jim has made in reconciling his running with his inadequate motivations.

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Consider first the implications of the causal theory which give no explanation of Jim's progress. The causal theory denies that Jim's running is justified either before or after his discovery and resolution of his real motives, i.e., prior to Jim's discovery his running is not justified, after discovering his motivations and prior to his formulation of R his running is not justified, and after formulating R his running is not justified. In what follows, I will refer to these three stages of this case as stages one, two, and three, respectively. A causal theorist may say that there is an impersonal justification in all three stages for the action which Jim performs, but he must deny at each stage that Jim's performing ofthat action is justified. As we have just seen, this answer can be maintained only if the causal theory can also explain the progress Jim makes toward the justificatory ideal in some other way than by claiming he comes to have a justification for the performance of an action where he previously only had a justification for the content ofthe action. We can categorize the options which a causal theory can appeal to by which to explain the movement toward the ideal as follows. First, the theory can appeal either to some present difference in Jim or to a difference there will be in the future. If the appeal is to some present difference in Jim, the options are several: (i) the appeal may be to some internal mental state of Jim which becomes (more) justified, (ii) the appeal may be to certain acts or omissions, or aspects of certain acts or omissions, which undergo an increase in their level of justification, or (iii) the appeal may be that Jim, himself becomes more rational. As far as I can tell, there are no other options to which a causal theorist can appeal. In order to show that the causal theory is inadequate, what needs to be done is to show that Jim's progress is compatible with no increases of the sort described in the last paragraph to which a causal theorist might appeal. I shall begin this extended argument to eliminate the available options by considering the appeal to features of the future. We shall see that this option is the least attractive, and thus we will devote the major portion of this elimination argument to features of the present and features of Jim himself to which a causal theorist might appeal in explaining Jim's progress.

4.

FEATURES OF THE FUTURE

The causal theorist might attempt to account for the case by claiming that the only difference is a future difference. So, for example, the causal theorist might hold that, given R, it is now true that in the future, Jim will justifiably run for Congress (perhaps when he comes up for re-election); whereas withoutR, he will not. On this option, no present difference exists except for the fact that it is now true that the future will be different than it otherwise would have been.

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This claim seems straightforwardly wrong, however. There is clearly a present difference between stages one and three, and any view which cannot explain that difference is inadequate. Once we have recognized our inadequate motivations and seen that it is better that our behavior not change, we are closer to the justificatory ideal, at that instant, than we were before. Were we to die in the next instant, our legacy should include our having made such an advance during the final moments of our lives. If the above explanation of the difference is all that the causal theorist can offer, all he can say is that we would have made such an advance had we not expired. Hence, the causal theorist must look at features of the present for an account of Jim's progress.

5.

INTERNAL FEATURES OF THE PRESENT

A more promising attempt looks for certain mental states to which a causal theorist might appeal to explain Jim's progress, mental states which in virtue of their enhanced justificatory state can explain Jim's progress toward ideal rationality. The answer to the question whether there are such mental states is, I think, no. First, the progress is not merely a matter of increased self-awareness. Jim is no more aware of himself after reconciling his inadequate motivations with his continued playing than he was before that reconciliation, i.e., no increase in self-awareness occurs between stages two and three. Yet, progress is clearly achieved between stages two and three, so we cannot explain his progress by appeal to some increased self-awareness. Also, we cannot explain the progress made by an appeal to an increase in the rationality of any of Jim's beliefs or desires. First, consider his desire to run for Congress. If Jim's desire is to run in order to show his critics wrong, this desire has the same irrational status both before and after constructing R. On the other hand, it might be claimed that Jim has the desire to run, after constructing R, in order to use his abilities for his constituents, thus making the desire to run a rational one where no such desire was rational before constructing R. The problem with this view is that Jim need not have any such desire. He may only intend to come to have that sort of desire, knowing (regrettably) that his only present desire is to show his critics wrong. So, in either case, the causal theory cannot be rescued by appeal to Jim's desire to run for Congress. An appeal to Jim's desire or intention to alter his motivational structure is of no use either. Jim could have added this desire or intention (and had either be justified) prior to constructing R and hence prior to resolving his motivations with the continuation of his campaign. In other words, such a desire or intention could have been added before stage three arises, and hence before the progress which needs to be explained had been achieved. In fact, if Jim is like the rest of us, he probably added this desire or intention in stage two prior to resolving his

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behavior with his motivations. And yet his distinctive progress does not occur until stage three. Hence, neither of these internal states can be the only explanation of the difference in Jim's state before constructing R and after constructing R. The final internal state to which a causal theorist might appeal is Jim's belief that he should (continue to) run for Congress. A causal theorist might claim that, before constructing R, this belief was not doxastically justified, for it was sustained by Jim's desire to prove his critics wrong; after constructing R, R comes (at least in part) to sustain that belief. Hence, the progress Jim makes is to be accounted for by noting that, before constructing R, Jim may have had ajustification for thinking that he should continue to run, but he did notjustifiably believe that claim. After constructing R, he comes to justifiably believe that he should continue the campaign. The difficulty with this attempt is that there is no reason to think that R must sustain in part the belief in question. The irrational desire to prove his critics wrong may be responsible both for his behavior and for his belief that he should continue the campaign. Jim may know this sad fact about himself, and try to sever the causal connection between his desire and this belief in addition to trying to sever the causal connection between his desire and his running for Congress. Nonetheless, it is still intuitively obvious that Jim has made progress; thus, appeal to the belief in question will not explain this progress. Moreover, there is something unsatisfying about the general approach suggested here, that Jim's progress can be explained by citing some additional mental states that are justified. Mere numbers of unrelated beliefs, desires, intentions, or other mental states would add to Jim's overall epistemic condition, but would not explain the unique kind of progress Jim has made. Furthermore, the mere addition of further justified mental states about the particular issue of running for progress won't explain his progress either. For note that such changes are bound to occur between stages one and two, for the simple reason that new experience can be counted on to provide additional evidence for new mental attitudes. Yet, the sense of progress that Jim makes between stages two and three is simply not there in the transition from stage one, where he is unaware of his inadequate motivations, to stage two, where he becomes aware of them. With this new awareness comes a host of new mental attitudes about himself and his situation, attitudes which we may presume to be justified. Some progress in terms ofjustification or rationality has been achieved because of this change, but it is not the distinctive kind achieved in the transition from stage two to stage three. This fact suggests that it is not in virtue of addingj Llstified mental states that explains the progress Jim has made. So, it would seem, appeal to internal states cannot salvage the causal theory from the case of the ill-motivated politician. Let us turn then to a different area to see if it offers more hope for the causal theory, for if internal

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states cannot explain what needs to be explained, perhaps external features, i.e., that which counts as overt behavior by Jim, can.

6.

ACTS, OMISSIONS, AND ASPECTS OF EACH

These external features include the acts, omissions, and aspects of each which characterize or might characterize Jim at present. One such external feature which cannot be of any use to the causal theorist is the act of running for Congress itself. That act had a justification for it before Jim discovered his motivations for performing it, and presumably the act itself is also justified after Jim constructs R. Further, the causal theorist cannot hold that Jim justifiably performs the act either before or after constructing R, for in neither stage does that which justifies the act causally sustain his so acting. A causal theorist might claim, though, that the act in question comes to have a greater justification, or perhaps a justification all things considered (of which Jim is aware), after constructing R. The appeal to a greater justification, though, does not explain the advance toward the justificatory ideal. For one can acquire a greater justification for believing, e.g., that all ravens are black just by seeing another black raven, without making any such advance. The intuitively obvious point about Jim is that he has made that sort of progress, and since greater justification can occur without such progress, citing it in this case does not explain that progress. Nor does the appeal to justification all things considered explain the progress. The only way for this appeal to explain the progress would be for the act to fail to be justified, all things considered, before Jim undergoes the reasoning process in question, for otherwise there would be no difference (on these grounds) between the first and second stages. Yet, when Jim was not aware of his poor motivations for running, he had ajustification, all things considered, for his campaign; so if we are to accept this explanation, we must hold that after finding out about his poor motivations, Jim loses this justification, and then regains it after engaging in the reasoning process described. This explanation is inadequate precisely because the process from lack of awareness to reconciliation through the reasoning process involves progress toward an ideal, whereas the proposed explanation leaves Jim at the same level after the total process as before. Hence, this attempt fails to free the causal theory of the counterexample of the ill-motivated politician. Could the causal theorist claim that Jim has greater justification than he had before for running for Congress? I think the answer is no. On the proposal above, Jim loses justification for running when he becomes aware of his inadequate motivations. This information defeats whatever justified his running in the first place. The force of the reasoning process is, then, to override the defeating information. When such overriding occurs, the force of the original

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justification is reinstated, but it is not enhanced. For enhancement to occur, some other explanation of the stages would have to be forthcoming. Perhaps a causal theorist might appeal to however Jim is proceeding in attempting to alter his motivational structure. Perhaps this act is justified and can explain Jim's progress. It cannot. Jim may be doing nothing at present to even attempt to alter his motivational structure. His intention may be simply to take any actions he can find to alter it, but he may not have found any as yet. Since there are no other actions which Jim must be performing at the time in question, perhaps a causal theorist will appeal to acts which Jim omits to perform to explain his advance in rationality. Perhaps one might appeal to Jim's not taking steps that will alter his desires and cause him to quit the Congressional race, or to Jim's not looking for acts to undermine the effects of his inadequate motivational structure. Any such explanation is adequate only if it is the omitting which is justified, and not just the content of the omission. If we suppose that only the omission (and not Jim's omitting) is justified, no progress will have been explained. Rather, such instances present an even greater need for progress toward the ideal in question because, in the case at hand, if only the omission were justified, we would have a case in which an omission occurs but the omitting is not justified. Such an explanation would add to Jim's problems regarding justification, not explain how he is eliminating them. So, any omission cited needs to be justifiably omitted. Regarding steps which would alter his desires and cause him to quit the race, it is hard to see why one would think Jim justifiably omits such steps. Perhaps ifhe had some steps in mind, he could justifiably omit them; but Jim may have no idea of how to go about altering his desires and thereby cause himself to quit the race. There simply is no good reason to suppose that Jim justifiably omits such actions. This argument does not affect Jim's omitting to look for such steps. Jim's not looking may be justified, but it is not clear that this fact helps the causal theory. When an absence of action is justified, at least in certain types of cases, such justification obtains only because some other action (which is not an omission) is justified. The sorts of cases in which this is so are cases where the action, the omission of which is justified, has a primafacie justification for it. F or example, if a doctor's failing to stop and help an accident victim is justified, it is so justified only in virtue of some other action overriding the importance of the first (such as being needed at a more serious operation at the hospital). In Jim's case, looking for a way to alter his motivational structure isprimafacie justified--at least in part because it is either a part of, or inextricably linked to, Jim's performing an action which will alter his motivational structure (an action which Jim correctly believes to be prima facie justified). So to say that Jim justifiably fails to look for such an action cannot be the end of the story. For to

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say that an omission of a prima facie justified act is justified requires the justification of some other action which implies that the primafacie justification for the omission is overridden. Thus, the difference in levels of rationality before and after having reconciled his bad motivations with continuing to run cannot be explained merely by claiming that certain omissions are justified. That may be true, but if it is, it is only true in virtue of Jim's justifiably doing something else. One obvious option here is that it is justified in virtue of its understood relationship to Jim's running for Congress in spite of his inadequate motivations, but that explanation is not open to the causal theory. For it would first have to be granted that Jim s running is itself personally justified since its impersonal justification is no different from stage one to stage three. Without appeal to this action and its justification, however, it is hard to see where to find an action whose justification confers justification on the omission in question. So we must conclude that this attempt at an explanation is only as good as some other one as yet forthcoming. The only remaining alternative is to claim that some of Jim's actions, or some aspects of his action, are justified while some others are not. The causal theorist might hold that Jim's running is not justified, though his attempting to help his constituents is. Or he might claim that Jim's running is not justified though his acting so as to alter his motivational structure is. This approach does not work either. For the aspects of the action, or the different acts (however one chooses to individuate actions), are inextricably linked. Perhaps some of the elements are primafacie unjustified whereas others are prima facie justified. Given the inextricable linkage that occurs, however, none of the elements can achieve actualjustificatory status without all the others achieving the same status. There may be possible circumstances in which the linkage is dissolved so that, say, Jim's running is not justified and yet his attempting to help his constituents is. But it would be quite regrettable if this possibility were taken to imply that the justificatory status actually diverges. For the only way to make sense of the transition from prima facie justification to actual justification is with reference to the entire set of elements of the actual circumstances--to say that a prima facie justified action is actually justified is to say that there is nothing else in the actual circumstances that overrides the primafacie justification. And to say that a prima facie unjustified action is not on the whole justified is to say that no other action has a primafacie justification strong enough to override the prima facie lack of justification in such a way as to justify the second action. But that is equivalent to requiring that the justificatory status of the elements stand or fall together, given that they are all parts of the same situation. Thus, the causal theorist cannot hold that Jim's playing is not justified whereas his using his talents is, and hence we must look I

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elsewhere if the causal theory is to escape the case of the ill-motivated politician.

7.

RATIONALITY OF THE PERSON

The final option open to the causal theorist is to claim that, whereas no progress is made in the areas considered above, progress is made in that Jim, himself is more rational after constructing R than before. It is, on this option, progress regarding the rationality of the person in question (rather than his (present or future) mental states, acts or omissions) which explains Jim's progress. In order to evaluate this attempt to rescue a causal theory, we must consider what it is for a person to be rational. When we claim that a person is rational, there are two things we might be claiming: first, we may be saying something about the collection of actual beliefs, actions, etc., of the person and noting that the collection is constituted by a sufficiently high degree of rational beliefs, actions, etc., to warrant calling the person a rational one; or, alternatively, we may be claiming that a positive evaluation applies to the character of that person. The first option is ruled out by the above discussion of the internal and external features of the case ofthe ill-motivated politician, for all the same points can be made about the presence of rational belief and action as were made about the presence of justified belief. So let us concentrate on the second option. On it, to say that a person is rational is to say something about the way in which that person determines what to do and how to do it, what to believe, what and how to change, or what and how not to change. In other words, we are saying something about the dispositions of the person in question to proceed rationally or justifiably in forming and holding beliefs, choosing actions, etc. To return to the case of Jim, our ill-motivated politician, the causal theory is claiming that Jim has better dispositions with regard to his actions, beliefs, desires, etc., after constructing R than he had before constructing R. There is something to be said in favor of the view that, through the process of self-discovery, Jim himself becomes more rational. Perhaps prior to learning of his poor motivations, he was disposed to form beliefs and perform actions in line with poor motivations; after becoming aware of his poor motivations, he is less inclined to do so. After learning that his irrational desire can prompt his behavior, perhaps he is less likely to form a belief or perform an action when all it has in its favor is that it satisfies such an irrational desire. This difference is not sufficient for the causal theorist. In the case of the politician, we have three separate stages: the first stage is where he is unaware of his poor motivations, the second is where he becomes aware of his poor

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motivations, and the third stage involves his reconciliation of his poor motivations with his continuing to play professionally. Any advance in the rationality of Jim's character, as clarified in the last paragraph, occurs in the second stage, for his awareness of his poor motivations and the role his irrational desire can play in his behavior have already been perceived prior to the reconciliation in question. The progress Jim makes for which we are seeking an explanation, however, occurs most obviously at stage three. Hence, this explanation fails to account for the data. It may be thought that Jim adds an intention in the third stage, so that this stage involves two distinctive elements: first, the reconciliation about the particular bit of behavior under question and second, an intention to alter his motivational structure if he can. It might then be claimed that the progress to be explained is that the additional intention is justified, and given its presence Jim is both better off now and will be better off in the future. The intention in question could just as easily have been added during the second stage, however, and if it were added at that point, it would still be the case that Jim makes progress toward ideal rationality in the third stage. Thus, the case does not depend on the additional intention at the third stage. Further, even if the added intention were central to the third stage, that would not explain the progress in question, for, as we saw earlier, appeals to desires, intentions, and increased self-awareness on their own do not explain the distinctive advance characteristic of stage three, as opposed to stage two, which involves increased self-awareness and new mental attitudes which can be presumed to bejustified. It appears, then, that the causal theorist has no resources whatsoever by which to explain the progress Jim makes toward ideal rationality. It is important to notice that none of my arguments against the causal view here presupposes a deterministic theory of causation. These arguments work just as well against the proposal that Jim's reasoning provides some degree of causal support, however minute. It is just as possible for this reasoning to occur and have no probabilistic causal impact on his behavior as it is for it to occur without having a deterministic impact. A denial of this possibility could be sustained only by arguing that reasons must always be causes, but such a claim wreaks havoc with the idea that Jim's running failed initially to be personally justified. For in stage one, Jim has reasons for what he is doing (he gives these reasons to himself and to others when asked), and hence if reasons are always causally active in some way, these reasons would have to be partial causes even in stage one. Such a maneuver would make a defense of the causal view even more difficult than it is on the assumption that reasons need not always be causes, for if reasons are always causes, then the causal view has no interesting story to tell to distinguish doxastic from propositional justification. No matter how causal theorists wish to view such a problem, however, the point remains that nothing argued here presumes a non-probabilistic account of

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causation. So there is nowhere for a causal theorist to turn for rescue from the case of the ill-motivated politician.

8.

CONCLUSION

The most natural account ofthis case is just this: before constructing R, Jim did not possess the kind of rationality which implies that he is justifiably running for Congress; but after constructing R, his running is rational in a way which implies that it is perfectly justified. The advance Jim makes is to be explained by his moving from performing a justified action to justifiably performing that action, from performing an impersonally justified action to performing a personally justified one. Such a conclusion gives us an account of the nature of justification that covers the variety of things to which it applies and one which fits well with Lehrer's intuitions about the gypsy lawyer and the racist scientist. The only relevant difference between the racist scientist and the ill-motivated politician, in this view, is that the scientist has no remorse for her racism whereas the politician has regrets for his motivational structure. In that way, the politician is better offthan the scientist. Still, the relevant beliefs and actions are on par, being justified by the reasons available to each person, contrary to the demands of the causal account of basing. One may worry here that in accepting the non-causal account of the case given above, we have lost the obvious point that there is something lacking about Jim and his relation to his Congressional campaign. That is not so. We can readily grant that Jim has not achieved ideal rationality, even if it turns out that the lack of rationality in his running for Congress is the last vestige of irrationality or lack of justification remaining among any of his acts, beliefs, intentions, desires, valuations, etc. In order to be ideally rational, Jim must have a proper character; and having a proper character requires being disposed toward rationality and justification in the arenas of action, belief, desire, intention, valuation, etc. Resolving his inadequate motivations with his continued running surely does not eliminate the character flaw he possesses, even if this event is part of the process toward character perfection. I close with one last word of speculation on the attractions of the causal theory. Perhaps the more fundamental kinds of knowledge, such as perceptual knowledge, are kinds for which meta-motivational reasoning processes such as those discussed here are not possible. Perhaps, that is, perceptual beliefs rely essentially for their justification on a causal element in perception, and no circuitous route through a meta-motivational reasoning process could make up for a faulty causal story about such beliefs. Given the central place that perceptual knowledge plays in the construction and defense of theories of

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knowledge, it would be understandable for theorists to generalize from what may be true of such fundamental kinds of knowledge to all knowledge of any type. It would still be a mistake, but an understandable one.

ENDNOTES I. This essay is written in honor of Lehrer's luminary career in philosophy, out of deep respect for his intellectual achievements and gratitude for his acquaintance and gracious assistance throughout my career. It is a privilege to know him, and I dedicate this essay to a splendid human being and brilliant philosopher.

2 Keith Lehrer, Knowledge, (Oxford: Oxford University Press. 1974), pp. 124-125; "Proper Function versus Systematic Coherence," in Jonathan L. Kvanvig, ed., Warrant in Contemporary Epistemology, (Lanham, Maryland: Rowman & Littlefield Publishers, Inc., 1996), pp. 25-46. 3 The common attitude is represented in discussion of the issue by John Pollock, who footnotes his claim that the basing relation is in part a causal relation as follows: "Lehrer has argued against this, but I do not find his counterexample persuasive," (Contemporary Theories of Knowledge, (Totowa, NJ: Rowman and Littlefield, 1986), p. 81). He offers no argument, supplies no discussion. 4 Keith Lehrer, Knowledge, pp. 124-125. 5 Keith Lehrer, 'Proper Function versus Systematic Coherence,' pp. 33-34. 6 See, for example, Marshall Swain, Reasons and Knowledge, (Ithaca: Cornell University Press, 1981), chapter 3. 7 See "Swain on the Basing Relation," Analysis, Vol. 45, No.3, June 1985, pp. 153-158. Lory Lemke criticizes my arguments in "Kvanvig and Swain on the Basing Relation," Analysis, Vol. 46, No.3, June 1986, pp. 138-144; I reply to his objections in "On Lemke's Defense of a Causal Basing Requirement," Analysis, Vol. 47, No.3, June 1987, pp. 162-167. 8 Robert Audi, "The Causal Structure of Indirect Justification," Journal of Philosophy, 1983, p. 406. 9 ibid., p. 407. 10 For a developed defense of the counterfactual theory of causation, see David Lewis, Countelfactuals, (Oxford: Basil Blackwell, 1973). II See, e.g., Jaegwon Kim, "Causes and Counterfactuals," in Ernest Sosa, ed., Causation and Conditionals, (Oxford: Oxford University Press, 1975), pp. 192-195.

Chapter 4 LEHRER ON KNOWLEDGE AND CAUSATION T odd Stewart University ofArizona

Keith Lehrer has argued that it is possible to have knowledge of a proposition despite the fact that one's belief in that proposition is causally unrelated to one's epistemic reasons. This is an interesting and contentious claim, but an assessment of it is not the task of this paper. Instead, I will argue that Lehrer, and perhaps one critic as well, both take Lehrer's theory to entail that knowledge is possible without causation by reasons, but that this is mistaken. Lehrer's theory as it stands actually delivers no verdict on the issue of whether proper causation is necessary for knowledge or a belief's being justified. While this means that the coherence of Lehrer's theory can be saved should his treatment of these issues yield counterintuitive results, it also means that the theory as it currently stands is incomplete. The theory simply does not make any predictions about certain kinds of examples, and this reveals that Lehrer's theory is unfinished in an important respect. Let us turn to the racist Mr. Raco, which is where Lehrer asserts that an agent can be completely justified and yet that agent's reasons need play no causal role in the explanation ofthe belief that is completely justified. Here is Lehrer's statement ofthe case: It is easy to imagine the case of someone who comes to believe something for the wrong reason and, consequently, cannot be said to be justified in his belief, but who, as a result of his belief, uncovers some evidence which completely justifies his belief. Suppose that a man, Mr. Raco, is racially prejudiced and, as a result, believes that the members of some race are sllsceptible to some disease to which members of his race are not susceptible. 63 E.J. Olsson (ed.). The Epistemology of Keith Lehrer, 63-74. © 2003 Kluwer Academic Publishers.

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KNOWLEDGE AND CAUSA nON This belief, we may imagine, is an unshakable conviction. It is so strong a conviction that no evidence to the contrary would weaken his prejudiced conviction, and no evidence in favor would strengthen it. Now imagine that Mr. Raco becomes a doctor and begins to study the disease in question. Imagine that he reads all that is known about the disease and discovers that the evidence, which is quite conclusive, confirms his conviction. The scientific evidence shows that only members of the race in question are susceptible to the disease. We may imagine as well that Mr. Raco has become a medical expert perfectly capable of understanding the canons of scientific evidence, though, unfortunately, he becomes no less prejudiced as a result of this. Nevertheless, he understands and appreciates the evidence as well as any medical expert and, as a result, has reason for his belief that justifies it. He has discovered that his conviction is confirmed by the scientific evidence. He knows that only members of the other race are susceptible to the disease in question. Yet, the reasons that justify him in this belief do not causally explain the belief. The belief is the result of prejudice, not reason, but it is confirmed by reason which provides the justification for the belief. Prejudice gives Mr. Raco conviction, but reason gives him justification. I

I find the case a bit underdescribed by Lehrer. Two critical pieces of the example are left unstated: (1) whether or not Mr. Raco, when asked about his belief regarding the susceptibility of a particular minority to some disorder, lists off the relevant scientific studies as his reasons, and (2) if Mr. Raco himself takes these scientific studies to be his reasons of ifhe simply gives these reasons to others to stop them from attacking his racism. I think that the case is meant to be one in which Mr. Raco does in fact respond to challenges by citing the scientific studies and in which he does sincerely take his reasons to be those studies. Mr. Raco does not realize that the root of his belief is his racism. What Lehrer intends is to put forward a case where the agent honestly takes his reasons to be ones which are not the actual cause of the belief or acceptance? The important thing to notice about the example is that Lehrer does clearly claim that Mr. Raco knows and is completely justified in believing that members of the race in question are susceptible to the disease. A brief sketch of the relevant pieces of Lehrer's theory is warranted at this point. Knowledge according to Lehrer is, roughly, completely justified true belief (acceptance).3 A belief is completely justified when it is both personally and verifically justified. 4 Lehrer uses complete justification as a technical term, so it is important that he explicitly claims that Mr. Raco is completely justified. This means that Lehrer thinks that Mr. Raco is both personally and verifically

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justified according to his theory. Lehrer's analyses of personal and verific justification will be discussed below when we turn to whether or not Mr. Raco is in fact completely justified in his racist belief according to the theory as it stands. Dirk Koppelberg has criticized Lehrer's claim that appropriate causation is not necessary for justification and knowledge. While Koppelberg never explicitly claims that Lehrer's own theory has this consequence, he does say some things that make it plausible that he thinks this. For example, he opens his "Justification and Causation" with the following: Coherence theorists subscribe to the thesis that epistemic justification consists in appropriately specified inferential relations among beliefs. In contrast many reliabilists hold that it is the causal origin or the causal sustenance of a belief which is responsible for epistemic justification ... Keith Lehrer and Thomas Bartelborth have vigorously argued that any theory ofjustification which allows for causal considerations is deeply mistaken. 5 From this, we can infer that since Lehrer is a coherence theorist and further thinks that any correct theory excludes causal factors as irrelevant to whether or not a belief is justified, Lehrer's own theory must exclude these causal factors, since otherwise Lehrer's own theory would (a) not be a coherence theory, and (b) be incorrect. This is such an obvious inference that I suspect that Koppelberg would endorse it. Again he never actually addresses the issue of whether or not Mr. Raco is justified according to Lehrer's theory since he is more interested in showing that Mr. Raco is not justified according to the various notions of justification that Koppelberg thinks to be correct. 6 Koppelberg ends his paper by making similar general remarks about causation and coherence theories. He writes, "A genuine coherence theory claims that epistemic justification consists in adequately specified inferential relations among belief contents--causal relations among belief states do not matter.,,7 Again, the inference to the claim that Lehrer's theory, insofar as it is a coherence theory, will entail that a belief may be justified even if it is not appropriately related to its justifying reasons is obvious. So, I think it fair to claim that Koppelberg would agree that Lehrer's theory is committed to the view that appropriate causation is not necessary for a belief's being justified. Of course, Koppelberg would use this to claim that Lehrer's theory is false, but this is not important at present. Interestingly enough, the arguments later in this paper will show that Koppelberg (and perhaps Lehrer as well if he sees coherentism as being logically incompatible with giving a role to causation) is simply incorrect to suppose that coherence theories must by their nature exclude the causal origin

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or sustenance of belief from consideration. For, while Koppelberg is correct that coherentism considers only inferential relations between beliefs, if the beliefs themselves have partially causal content, the inferential relations themselves will be impacted by this. While it is still presumably true that the facts of causation themselves do not matter when it comes to being personally justified (as I will explain below), when we add whatever Gettier conditions, etc., are necessary in order to create an account of knowledge, the facts about the causation of a belief may become relevant. And we should always remember that Lehrer is ultimately interested in an analysis of knowledge, and hence Gettier conditions are an important component of his theory. In his theory, verific justification plays the role of bridging the gap between personal justification and knowledge. And, as I hope to show, verific justification leaves room for appropriate causation as a necessary condition for knowledge, as it is a possibility that claims about what is a reason for what have a causal component built into their content. 8 So, while it is perhaps true that bare coherence theories do not make room for causation, when we add whatever is necessary to these theories for an account of knowledge, causation may become relevant once again. Now that we have seen that both Lehrer and a critic take Mr. Raco to be completely justified according to Lehrer's theory, we must assess whether this is correct. Recall that, according to Lehrer, a belief is completely justified if and only if that belief is both personally and verifically justified. Let me now briefly sketch Lehrer's basic theory of personal justification, and explain why Lehrer's theory says that Mr. Raco is personally justified (assuming that he meets all of Lehrer's other conditions). According to Lehrer's final account of personal justification: S is personally justified in accepting that p at t if and only if everything that competes with p for S on the basis of the acceptance system of Sat t is beaten or neutralized on the basis of the acceptance system of Sat t. 9 A proposition C competes with p for an agent (given her acceptance system) if it is less reasonable for that agent to accept p on the assumption that c is true than to accept that p on the assumption that c is false.1O In other words, c competes with p iff Rs(P/c) < Rs(P/~c).1l Proposition p beats c for S iff c competes with p but it is more reasonable for S to accept that p than to accept that c on the basis of the agent's acceptance system (all at a time). Again, we might express this as:p beats c iffRs(P/c) Rs(c). Finally, n neutralizes c as a competitor of p for S iff c competes with p for S, but the conjunction of nand c does not compete with p for S, and it is as reasonable for S to accept this conjunction as to accept c alone according to S's acceptance

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system. This can be represented as: n neutralizes c as a competitor of p iff (Rs(P/c) < Rs(P/~c) and Rs(P/(c !\ n)) ~ Rs(P/~(c !\ n)) and Rs(c !\ n) ~ RS(C).12 In the case at hand, Mr. Raco does meet all of these conditions. In terms of the scientific evidence which Mr. Raco believes, all competitors to Mr. Raco's beliefs are beaten or neutralized. For example, if the skeptic suggests (as per the justification game) that one of the scientific studies could be inappropriate, Mr. Raco can respond that given his knowledge of how the studies were conducted, etc., it is more reasonable for him to believe that the studies are fair and accurate (this competitor is hence beaten). But, suppose the skeptic offers the following competitor: c.

You (Mr. Raco) are not causally influenced in your belief by the scientific evidence.

Mr. Raco can neutralize this competitor by claiming something like the following:

n.

The scientific evidence I possess shows that what I believe is true, and it really doesn't matter whether or not the possession of the evidence in this case causally influences my belief. I am concerned in believing what is true about who suffers from this disease, so why should I care about the causation of my belief?

Proposition n can neutralize c, assuming that c does in fact compete with the racist belief, because the conjunction of c and n does not compete with p given Mr. Raco's beliefs and it is at least as reasonable for Mr. Raco to accept this conjunction as to accept c alone given his acceptance system.13 For, we can stipulate that Mr. Raco does in fact accept various things that do appropriately support n. Hence, c is neutralized and Mr. Raco is personally justified in his belief despite the evidentially-illicit causation of his belief. So far, we have seen that Lehrer's theory does entail that Mr. Raco is personally justified. But, is Mr. Raco verifically justified? Unfortunately, I think that Lehrer's theory as it stands does not deliver any verdict on this issue. Further, this failure can be traced to the fact that Lehrer's theory actually takes no stand at all on whether appropriate causation by reasons is necessary for a belief to be completely justified or an instance of knowledge. Here we should separate Lehrer from his theory; clearly, Lehrer thinks that causation is not required for justification. But, surprisingly, Lehrer's theory as it stands does not commit itself on this question. Let us now turn to the argument for this claim. An agent's verific justification system is what remains of her personal j ustification system but with

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all false beliefs deleted. If belief in a given proposition can be justified on the basis of what remains (and these propositions can all be verifically justified as well, and so on until a special kind of circle emerges), then that belief is verifically justified. Thus, if we wanted to show that Mr. Raco is not verifically justified in his racist belief, we would need to locate false beliefs that will be used in support of the belief in question (either directly or in the handling of competitors suggested by the skeptic). And, this is the heart of the problem: Lehrer needs to explicitly claim that certain propositions are true or false in order for his theory to entail that Mr. Raco has or lacks verific justification. But, Lehrer's theory as it stands simply does not do this. Because of this, it is impossible to say whether Mr. Raco's racist belief is verifically justified according to the theory. To see this, suppose that the skeptic makes the following claim during the ultra-justification game: 14 c.

Mr. Raco, the reasons you give for your belief that the minority suffers from a disease are good reasons but they are not your reasons because they have no causal influence on your belief. As this is the case, despite the fact that they are good reasons, since they are not your reasons, they do not justify your bel ief.

Before moving to Mr. Raco's reply to competitor c, a brief discussion of a reason vs. one's own reason is in order. I think that there is a fairly intuitive difference between the two that can be brought out by considering cases where one has lied about why one believes something but has nonetheless provided a good reason for the belief. Suppose that Wendy is trying to convince her friend Greg that a certain mathematical theorem is true. Knowing that Greg is a bit slow when it comes to math, she claims that Mr. Mathright (their high-school calculus teacher who was renowned for his care, professionalism, and precision) said the theorem was true. Actually, Wendy holds the theorem to be true because she proved it herself one afternoon in a fit of inspiration. IS Mr. Mathright did say that the theorem is true. But, Wendy is a bit of a skeptic about trusting others; she refuses to take anyone's authority as a justification for a mathematical claim until she can establish it for herself. Awareness of Mr. Mathright's assertions and reputation alone would suffice to justify most people's acceptance of the theorem. 16 So, as it happens Wendy has offered a good reason for accepting the theorem to be true. But, it is not her reason. She lied to Greg to simplify matters. Wendy believes the theorem on the basis of her proof. When one gives one's own reason, one is tacitly making a claim about the causation of one's beliefs; this explains how it is possible to lie about one's

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reasons while still giving what is a good reason. Causation is actually part of the content of certain reasons claims, and hence relevant to their truth or falsity. So, when Wendy claims that she accepts a certain mathematical proposition on the basis of Mr. Mathright's testimony, a necessary condition for the truth of her claim is that Mr. Mathright's testimony itself or her belief that there was such testimony was in some part causally responsible for producing or sustaining the belief in the mathematical proposition. Because this causal component is false in Wendy's case (and further we may assume that Wendy believes it to be false as well - this must be added so that Wendy counts as actually having lied), Wendy has lied about her reasons for accepting the mathematical proposition. I? This, I hope, helps to make sense of c above; causation can and does enter the picture where one's own reasons are concerned. The skeptic then claims that only one's own reasons are relevant to justification. This is the skeptic's objection to Mr. Raco. So, what can Mr. Raco say in response to c? He could try to beat this competitor by saying the following: b.

Justifying reasons need not be my own reasons (in the sense just clarified). The reasons I just gave are the ones that justify me (Raco) in believing what I do whether or not these reasons have any causal influence on my belief in this case. For example, the valid deduction of a conclusion from justified premises (when I know that these premises are justified and the deduction valid) is enough to justify my belief in the conclusion even though the these facts are not the causes of my belief in the conclusion. IS

But, here it matters very much whether b is true or false. One can only beat or neutralize a competitor in the ultra-justification game with a proposition if that proposition is true. Otherwise, the skeptic is allowed to delete the belief and make any other necessary adjustments to the agent's doxastic system in light of this deletion. So, if b is true, and Mr. Raco responds to c with b, then b beats c and Mr. Raco is verifically as well as personally justified in his belief (assuming that b is in fact both personally and verifically justified as well). Hence, he knows thatthe minority suffers from some peculiar and otherwise rare disease. However, if b is false, then the skeptic can say this, excluding b from use in the ultra-justification game. This means that b would not beat c, and therefore Mr. Raco would not have knowledge according to Lehrer's theory as it is not the case that all competitors have been beaten or neutralized. 19 Thus, we can appreciate the critical importance of the truth or falsity of b in Lehrer's theory.

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The problem is that Lehrer's theory does not actually tell us whether b is true or false. The core of Lehrer's theory-all of Lehrer's definitions, formal principles, etC.-is compatible with conflicting judgements about Mr. Raco; if b is true, then Mr. Raco is verifically justified in his racist belief, but if b is false then Mr. Raco is not verifically justified. One way of better seeing this is by noticing that one could adjust Lehrer's theory to require appropriate causation merely by understanding all reasons claims as about one's own reasons. Mr. Raco's own reasons are not the scientific studies but rather his racism (if we count this as a reason at all). Therefore, when Mr. Raco replies to the skeptic with b and the skeptic rebuts him and deletes the proposition from Mr. Raco's acceptance system, Mr. Raco is left without good reasons for his racist belief. Thus, this belief will fail to be verifically justified and will not be an instance of knowledge. To secure this result, however, no changes were made anywhere to Lehrer's stated theory of knowledge and justification. No definitions were adjusted, nor were any principles rewritten. Even the spirit of Lehrer's theory is preserved here; only our conception of how we are related to a fact, as encoded in the statement of our reasons for acceptance, and truth and falsity (as the externalist bridge between personal justification and knowledge) are relevant to justification. 20 This in itself helps make clear that Lehrer's theory simply does not entail a verdict except in light of the truth or falsity of various propositions which the theory itself does not entail. The deeper significance of this sort of concern is that Lehrer's theory is incomplete as it stands. In particular, it will only deliver verdicts about certain kinds of cases when it is supplemented by specific claims as to the truth or falsity of certain propositions that might be used to beat or neutralize various skeptical objections. For, an agent can be personally justified in accepting that a proposition beats or neutralizes a competitor or objection and yet not be verifically justified in believing this. This reveals a more troubling problem for Lehrer's theory: all of the definitions and principles do little to actuaIly pin down exactly when an agent is verifically justified. These principles wiIl need to be supplemented with various contentful claims about what is true and false before it will be possible to derive results about verific justification. 21 This leaves us with the question as to whether it matters that Lehrer's theory is incomplete. On the one hand, the incompleteness of the theory means that it may be adjusted in all sorts of ways without changing the existing theory itself. So, as I argued above, Lehrer's theory can be made to account for the intuition that Mr. Raco's racist beliefis not an instance of knowledge by adding a claim about the falsity of a certain proposition that will be employed by the agent when she attempts to neutralize or beat the skeptic's objections in the ultra-justification game. And, it might be considered a considerable virtue of a theory that it remains silent about, yet compatible with, all sorts of contentious claims about the relationship of causation to justification, etc. At the very least,

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the theory is weaker than it perhaps appears, but hence more flexible because of this. In some sense, this is as it should be since Lehrer's theory is fallibilist and allows that an agent can be personally justified and yet lack knowledge. But, it also makes clear that the externalist components of Lehrer's theory- namely the creation of an ultra-system by the deletion of all false beliefs-play such an important role that we can only assess knowledge claims according to Lehrer's theory if we have an indication of exactly what propositions are true and false and hence which propositions an agent may use to neutralize or beat objections, remembering that all false propositions will be deleted by the skeptic in the ultra-justification game. Lehrer's treatment of the Mr. Raco case makes clear what Lehrer thinks, namely that knowledge is possible without causation by justifying reasons. But, Lehrer would need to explicitly add claims about the truth or falsity of various kinds of propositions likely to be employed to meet the skeptic's objections in the ultra-justification game to his theory for it to entail this result. On the other hand, this incompleteness makes Lehrer's theory very difficult to assess, and might even make the theory nearly unfalsifiable. Testing our intuitions against the theory as it stands may be impossible in some cases, as with Mr. Raco. Critics will have to be extremely careful to make sure that Lehrer's theory really does deliver certain results before they can present compelling counterexamples. Because of this, it might be best to focus on the general structural features of the theory and refrain from the usual sort of counterexamples until the theory is modified so as to have clear consequences about various kinds of cases, but this severely limits our ability to determine whether or not Lehrer's theory is a good one. The flexibility of the theory is here purchased at the cost of our ability to test the theory in various respects. I have argued that Keith Lehrer's theory of knowledge does not in fact have some of the consequences that Lehrer and others have taken it to have. In particular, Lehrer's theory as it stands remains silent about the relationship of causation to justification. Indeed, it seems possible to easily accommodate the view that causation is necessary for justification by simply understanding reasons claims as always being partly causal. Causation would enter the picture here because it is explicitly represented in reasons claims, and improper causation can make such reasons claims false. Of course, Lehrer's theory is also compatible with the view that justifying reasons need not be causal. Whether the incompleteness of Lehrer's theory is a virtue or a vice, and both the flexibility and difficulty of assessment this incompleteness reveals, I leave to the reader to decide. 22

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ENDNOTES I Lehrer (1990), pp. 169-70. The Mr. Raco case also appears in Lehrer's more recent (2000) second edition in an essentially unchanged form on p. 196. 2 Dirk Koppelberg understands the case in basically the same way. See his (1999), p. 452. 3 Hereafter I will speak in terms of belief rather than acceptance merely for ease of exegesis. Acceptance, however, is not the same as belief according to Lehrer; rather, acceptance is something like belief with the goals of believing truths and avoiding falsehoods. 4 See Lehrer (1990), p. 149. 5 Koppelberg (1999), p. 447. (, In some sense, Koppelberg never takes Lehrer's theory of justification very seriously at all. Koppelberg never assesses Lehrer's theory but rather simply argues that Mr. Raco is not justified according to various other conceptions of justification. Insofar as there is any direct contact between Koppelberg and Lehrer, it is that Koppelberg would deny that Mr. Raco has knowledge of the proposition belief in which is sustained or caused by prejudice. See fn. 21, p. 460. 7 Koppelberg, p. 459. 8 One might argue that what this shows is that Lehrer's theory is not really a coherence theory after all. This taxonomic maneuver strikes me as unsatisfying, though. Lehrer's theory strikes me as an exemplar of a certain type of coherence theory (with certain externalist components of the sort needed to solve the Gettier problem), and it would do injustice to our taxonomy to classify it otherwise. In particular, I think that we will always have to add non-coherence factors - most obviously truth - to our account of knowledge, and so as long as one's basic theory of justification is coherentist, one should be classified as a coherentist. This does seem true of Lehrer's theory. 9 Lehrer, p. 126. 10 For convenience, I have dropped reference to a specific time t t!'om the definitions. II I intend Rs to be interpreted as reasonableness given acceptance system S. Obviously, reasonableness is not the same thing as probability on many interpretations of probability, and the notation I use is strikingly similar to that of the probability calculus. According to Lehrer, as reasonableness is a primitive normative notion, it seems unlikely that any view of probability which is non-normative could adequately cxpress Lehrer's position. But, the point of my use of this notation here is simply to help make clear some of Lehrer's definitions in a condensed format. 12 All of these definitions can be found in Lehrer, pp. 117-126. 13 It is not actually clear to me that c as I state it does compete with Mr. Raco's racist belief. But, if it does not, the skeptic can presumably work c into something that is a competitor that can be neutralized (or perhaps beaten) with something approximately like n. For example, the skeptic might claim that it unreasonable to hold a belief if it is not causally responsive to evidence. We could then understand n as rebutting this further claim which would act as a competitor to the racist belief. 14 In the ultra-justification game, the skeptic is allowed to simply delete any false propositions (and all propositions that logically imply this proposition) used in the defense of some other proposition, disqualifying such stricken propositions from use as justifiers. This is core of the difference between the justification and ultra-justification games. See Lehrer, pp. 141-44. 15 Read the "because" in this sentence as both causal and justificatory. 16 I wish to remain neutral on how it is that testimony justifies what the content of what the testifier says (viz., whether testimony proceeds on the basis of perception and induction, or whether it has some sort of intrinsic a priori authority as a basic source of belief, etc.). I use testimony here only because it helped make for a clear example. 17 I am being intentionally vague here about exactly what is to count as a reason. Is it Wendy's belief that Mr. Mathright testified, or Mr. Mathright's testimony, or something else entirely? I do not think that my argument depends on any specific construal of a reason, so I leave it to the reader to supply their own preferred notion. What I am suggesting, however, is that one could very easily

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build an explicit causal component into the truth conditions for at least some of these conceptions ofa reason. 18 I think we need to treat this proposition as beating the skeptic's objection rather than neutralizing it because one cannot consistently believe both c and b. Second, I will admit that I am a bit concerned that it is far from likely that any average person, even one with a bit of philosophical savvy, would respond to the skeptic's challenge in this way. I fear that perhaps Lehrer's account may exclude many intuitive cases of knowledge. But, this is an argument for another time. 19 Interestingly enough, one might try to explain differences in intuition (which a small poll has revealed do seem to diverge) about the Mr. Raco case by focusing on one's attitude towards b. If one thinks that b is true, then one will likely have the intuition that Mr. Raco does have knowledge. On the other hand, if one sees b as false, then one will be inclined to deny that Mr. Raco has knowledge. 20 See Lehrer (1990), p. 153. 21 I suspect that this problem is not limited to various causal principles of justification. For example, the skeptic might challenge certain people on the grounds that their justifications are too short. Instead of presenting any content-dependent reasons for accepting thatp, suppose the agent simply argues that she is trustworthy in what she accepts and hence, given that she accepts that p, p is likely to be true (this argument will work for any proposition which the agent accepts). Suppose that the skeptic objects that not everything that the agent believes can be justified with this universal argument. Suppose that the agent replies by simply reapplying the simple argument again: since the agent accepts that his justifications are long enough to justify his beliefs, and what he accepts he accepts in a trustworthy manner, it is probably true that his arguments are long enough to justify his belief. Is this an effective way of beating the skeptic's objection? This will depend where verific justification is concerned on whether or not the agent's reply is in fact true. But, does Lehrer's theory as it stands tell us whether or not we can use this simple universal argument to completely justify all our beliefs? This is not clear to me. 22. Thanks to Keith Lehrer for his support and comments on drafts of this paper. Thanks also to Erik Olsson and to Paul Thorn for their extremely helpful suggestions.

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REFERENCES Koppelberg, Dirk. "Justification and Causation." Erkenntnis 50, 447-462 (1990). Lehrer, Keith. Theory of Knowledge. Boulder, co: Westview Press, 1990. Lehrer, Keith. Theory of Knowledge, Second Edition. Boulder, CO: Westview Press, 2000.

Chapter 5 CAN WE GRASP CONSISTENCY? Volker Halbach University of Constance

In this paper, I will scrutinize a family of arguments which are supposed to show that consistency is not accessible in an epistemically relevant sense. If these arguments were sound, then consistency would be on a par with external facts: neither are directly accessible to us. External factors are not directly accessible because they need to be mediated in some way. Consistency would be inaccessible, according to these arguments, because proving or determining consistency in the relevant cases exceeds our intellectual capabilities. Thus, if consistency were actually inaccessible, then consistency could hardly playa role in an internalist account of epistemology. Traditionally (for instance, in Schlick's account (1934)), however, consistency has been seen as a main ingredient of coherence. Modern epistemologists, like Bonjour (1985), have also used consistency as a criterion of coherence, and they have even used consistency in order to define coherence. The arguments against the accessibility of consistency jeopardizes this central role of consistency in any internalist account of epistemic justification. I Thus, epistemic justification cannot imply the consistency of the belief system. If consistency is not directly accessible, then it cannot be used as a criterion for consistency on an internalist account. Keith Lehrer's epistemology is not internalist. Internalist justification, however, is an important ingredient of Lehrers's account since internalist justification is a necessary condition for 'full' justification. Because of the Gettier problem, external factors enter the definition of one form of epistemic justification on Lehrer's account. Lehrer (1990b), for instance, distinguishes between personal and undefeated justification. External factors form part of the definition of the latter. Undefeated justification is then used in the definition of 75 E.J. Olsson (ed.), The Epistemology of Keith Lehrer, 75-87. © 2003 Kluwer Academic Publishers.

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knowledge. As we will show, this account of internalism makes Lehrer's theory as vulnerable to the arguments mentioned above as an actually internalist theory-if consistency is employed as a condition for internal justification. Lehrer's opinion on the relationship of consistency and justification has not been constant, as I will show below. In (1991), he explicitly endorses the view that consistency is a necessary condition for justification: 2 Our acceptance systems may not be deductively closed, but the deductive closure of an acceptance system fully articulates the logical content of the system. The content of an inconsistent system would, therefore, be useless for the purposes of justifying anything and would, consequently, fail to serve as the basis of knowledge. Thus justification implies the consistency of the acceptance system. 3 The quoted passage does not imply that we have a direct grasp of the consistency of our acceptance system, and Lehrer avoided, as far as I can see, such strong claims. The reason for avoiding such a commitment may be, in part, the argument I will discuss in this paper. Implicitly, however, consistency is also central for Lehrer's theory, for an inconsistent theory logically refutes any given belief. One would like to conclude that an inconsistent belief system therefore also defeats any belief. It seems hard to see how Lehrer can avoid that consequence, although he must deny this when claiming that beliefs can be justified on the basis of an inconsistent belief system. Therefore, one has to be, at least, very careful about inconsistency. The reader is sent to the above mentioned papers (Lehrer 1990a) and (Lehrer 1999) for a discussion of this topic. At any rate, it seems interesting to see to what extent consistency can be used as a criterion for justification and coherence in a framework like Lehrer's. In the following, I will discuss the arguments against the accessibility of consistency in a general setting in order to see whether consistency can be used as a criterion for epistemic justification. I will not explore what consequences are implied for particular theories like Lehrer's or Bonjour's. The point of this paper is modest: I will show that some of these arguments have been accepted rashly and that their scope is more limited than is often assumed. I hope that this is interesting enough. For these arguments have had a major impact, and they have influenced many epistemologists. Thus, I will examine whether the arguments actually demonstrate that consistency is not accessible and, in this respect, is much like an external factor. The problem is vague, of course. In the first place, it has to be specified whether one is dealing with the consistency of arbitrary sets of beliefs or only with the consistency of one or more specific sets like one's belief system, (i.e., the set of beliefs one accepts). Moreover, I have to specify for whom consistency is or

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is not accessible. Is consistency accessible only to intellectually perfect beings with no limits of their computational powers, or also to human beings with their imperfections? The arguments differ in their scope. Some purport to show that consistency is inaccessible to agents with limited computational abilities, while other are supposed to apply to perfect agents too. Furthermore, accessibility itself is a vague notion. Must we have a 'direct grasp' of consistency, or are we allowed to employ auxiliary resources in order to prove or check consistency? For instance, may we calculate with the aid of paper and pencil, or even with the aid of a computer? Rather than giving here at the beginning a precise account of accessibility, consistency, and so on, I will instead examine what is achieved by the respective arguments, since they differ widely in their scope. As we shall see, some arguments actually prove that consistency is not accessible in a very strong sense; but accessibility in this strong sense hardly matters for the purposes of epistemology. The arguments against the attainability of consistency for epistemological purposes rely on an assumption about belief systems; viz., that belief systems can be represented by sets of sentences. Something can be said for the view that belief systems are more than just pure sets of sentences. However, for our purposes considering sets of sentences and their consistency is sufficient: a belief system is consistent if and only if the corresponding set of sentences is consistent. If this assumption were denied, then the arguments I will scrutinize would not get off the ground at all, and there would be no need to refute them. In the following, I will consider the arguments. I start with the most radical and basic arguments, and then move to more sophisticated arguments. In particular, I will move on to arguments that rely on more and more technically sophisticated arguments.

1.

A SIMPLE ARGUMENT

The following is the most radical argument I will consider. According to this argument, consistency cannot be checked by human beings for more than a very limited number of beliefs. Thus, not even reference to the complexity of truth tables, or similar metalogical aspects, are envoked. In his presentation ofChemiak's (1986) account, Hooker (1994) writes: In practice, humans can only juggle a few beliefs simultaneously in consciousness to check for consistency, to make and check inferences, and so forth-less than ten for most of us, and only so long as they are simple in structure. [ ... ] It is simply not possible to carry out even partial global consistency checks, [ ... ]

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An even stronger claim is made by Kornblith (1989, p. 211): It is not simply that human beings have difficulty in determining the con-

sistency of large sets of sentences. It is simply beyond the powers of any possible computational device to determine the consistency of a large set of sentences.

I agree that human beings are not able to determine the consistency of arbitrary large sets of sentences for their consistency. But in order to attain justification a subject only has to prove that its own belief system is consistent. Thus, Kornblith seems to think that humans are not able to establish the consistency of a set of sentences that is as large as our belief systems. However, it is not in general impossible for human beings to establish the consistency of certain large and even infinite sets. Kornblith's claim taken as a universal statement is simply false. It is not generally beyond the powers of any possible computational device to determine the consistency of large sets of sentences. Logicians prove consistency of infinite sets of axioms all the time. Peano Arithmetic PA, for instance, is given by infinitely many axioms and cannot be axiomatized by a finite set of axioms. Nevertheless, it does not exceed the capabilities of the average logician to show the consistency of PA by providing a model, or by proving its consistency in Gentzen's style (cut elimination). Further examples can be found in abundance. In general, a high cardinality of an axiom set does not prevent logicians from providing consistency proofs. In general, consistency proofs do not require that we juggle all sentences of a set simultaneously in consciousness; this is not necessary for carrying out consistency proofs. In a consistency argument, we do not have to use the sentences of the set in question, which is impossible; rather we only have to talk about them. The latter is no problem; we can say that all sentences in a set have a certain property. In particular, we can ascribe certain formal properties to all sentences in a set and finally arrive at the conclusion that a contradiction cannot be derived from these sentences. Therefore, the argument does not show, by any means, that we cannot determine the consistency of sets with more than ten sentences.

2.

THE SOPHISTICATED ARGUMENTS

I now turn to more elaborate arguments. These arguments, it is claimed, show that consistency is inaccessible to human epistemic subjects for metamathematical reasons.

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There are, at least, three results in metamathematics that have been employed in order to prove the inaccessibility of consistency. The arguments fall into three classes: • Complexity of truth tables. This point concerns consistency only with respect to propositional logic. Propositional logic is decidable; a straightforward method for checking it is provided by the truth table method, which is taught in almost any introductory course to logic. There are 2n many different assignments of truth values to n propositional variables. Thus, a propositional sentence with, for instance, 12 propositional variables yields a truth table with 212 = 4096 many lines. It is easily seen that even very simple sentences are hard to check for consistency with the truth table method and practically cannot be checked for consistency by the truth table method. • Undecidability of predicate logic (Church's Theorem). In contrast to propositional logic, predicate logic is not decidable. There is no decision procedure to determine whether a given (recursive or even finite) set of sentences is or is not consistent. This argument is essentially different from the preceding because it shows that there are general recursiontheoretic problems in checking a set of sentences for consistency, not just "practical" problems. • Unprovability of consistency (G6del's Second Theorem). No system satisfying some minimal requirements can prove its own consistency. There is not only no decision method for consistency, but we also cannot even stumble by chance over a proof of consistency. We cannot show in our system of beliefs that the set of all beliefs is consistent. Only this argument needs the requirement that the consistency of the set of beliefs must be proved within the belief system. Thus, it is different from both preceding arguments. How conclusive are the three arguments? Do they show that consistency is like an external factor in being out of our control and in being (in the relevant cases) inaccessible to us?

2.1.

Truth Table Complexity

According to this argument, checking belief systems for consistency may be feasible for computational devices exceeding our capabilites, but human beings are not able to carry out computations required for consistency checks of 'normal' belief systems. While consistency might be accessible to ideal epistemic

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agents with less restrictions on their computational capabilities, human beings are precluded from checking or establishing the consistency of their belief systems. Cherniak (1986) has emphasized the relevance of the complexity of truth tables for consistency checks in epistemology. Even comparably short sentences yield many lines in their respective truth tables. Does this imply that consistency is not verifiable in cases that matter for the coherence theory of knowledge? Arguments involving the complexity of truth tables should not impress the epistemologist. In the first place, there are methods other than truth tables for checking a set of sentences for its propositional consistency. In fact, these other procedures may terminate very quickly. These tricks are taught in introductory logic courses. Furthermore, it is not unnatural to assume that the elements of a belief system have a not too complicated propositional structure. Even if the belief system of a person is built up from many propositional atoms, they will hardly be combined in one complicated sentence. In practice, humans are unable to grasp sentences with excessively many propositional atoms. 4 At a propositional level, a typical belief system will consist of many unrelated sentences; they will stand alongside each other without many connections. And it is easy and not complex to check a set {PI, P2, P3, ... } for consistency because we do not have to go through all lines of the truth table. In order to instantiate the claim that belief systems are usually very simple at the propositional level, I could present physical and mathematical theories formalized in propositional logic. It should be obvious that the resulting propositional sentences would be very simple. Thus, the arguments relying on the complexity of truth tables for checking consistency do not threaten the claim that consistency is accessible to us. From these arguments, it cannot be seen why a person should not have grasp of the consistency of his or her system. Truth tables are a very bad tool for checking consistency. I do not want to challenge their value for didactical purposes, but they are hardly ever employed in consistency proofs outside of the toy world of propositional logic. Since the argument concerning truth tables does not show that the consistency ofhis/her belief system is not accessible to a subject, I leave propositional logic and tum to predicate logic. Propositional consistency does not matter anyway. What matters is general consistency, which is much better parsed as consistency in quantificationallogic.

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Church's Theorem

The arguments of the second class, relying on Church's Theorem, provide a harder challenge. Church's Theorem does not claim that consistency of a given system is hard to compute, rather it states that there is no general method for checking consistency, at least not for epistemic agents whose computational capabilities do not exceed those of Turing machines. Therefore, it cannot be argued as above that there are somehow better methods to decide whether a belief system is consistent. Church's Theorem concerns all possible methods of checking consistency of arbitrary systems without regard to their computational complexity. Church's Theorem states that there are no such methods at all. First, I will show that a certain direct retort does not succeed. It has been argued that the computational capabilities of human agents are not limited to those of ideal Turing machines. Obviously, the argument involving Church's Theorem relies on the assumption that epistemic agents do not have means to check consistency that go beyond those of ideal computer programs. But, obviously, this assumption also obtains: real humans have only finite resources, which are much less than a Turing machine has. The latter has unlimited memory, no temporal limitations for computations (as long as they are finite), etc. What ideal epistemic agents can or can not do may, naturally, be controversial. It can be claimed consistently that ideal epistemic agents are not bound to recursive methods. God, it may be said, is an ideal agent and he/she knows how to solve any problem whether it is computable (in the sense of recursion theory) or not. Although there is no inherent mistake in the concept of such an ideal epistemic agent, it is not interesting for the present topic. In the following, I will not consider agents who have justified divine intuitions about the consistency of belief sets. Nevertheless, I do not think that Church's Theorem shows that consistency is inaccessible. It shows only that we do not have a general method for deciding whether a set of sentences is consistent or not. It does not show that we cannot decide and even prove consistency in all relevant cases. Here it is useful to take a closer look at the proof of Church's Theorem. Using G6del's techniques, it is shown that there is an undecidable finitely axiomatized theory Q, called Robinson's arithmetic. 5 In particular, there is no general recursive method for deciding whether a given sentence A is provable in Q or not. This is a consequence of G6del's First Theorem for Q. If fA Q is the conjunction of all axioms of Q, then there is also, consequently, no recursive procedure for deciding whether fA Q ----> A is logically valid or not. Hence, there is no recursive procedure for deciding whether any arbitrary sentence is logically valid or not. From this it can also be deduced that consistency of a given sentence in

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predicate logic is not decidable. A sentence A is consistent with Q if and only if Q does not prove ....,A, that is, if and only if fA Q - t ....,A is not logically valid. But, as shown above, there is no recursive method to check whether a sentence of the form fA Q - t ....,A is logically valid or not. Thus, there is no effective procedure for deciding whether a sentence A is consistent with Q, or for deciding whether fA Q 1\ A is consistent. The most plausible strategy for defending the accessibility of consistency consists in the denial that a general method for checking consistency has to be applied. This means that the description above of how we should revise our belief system is faulty. There is no simple check for consistency; rather, we sometimes have to try hard to establish consistency. But still we can say that a set of beliefs is only justified if its consistency has been demonstrated. Of course, there is no general procedure for checking consistency, but why should an epistemic agent be required to have a general procedure for deciding whether an arbitrary set of sentences (belief system) is consistent or not? For obtaining epistemic justification, he needs a consistency proof for his very own belief system, but not for the belief system of other people or any other belief system different from his own. This description is compatible with Church's Theorem. It does not follow from this theorem that we cannot prove the consistency of the system Q. That is, we might be able to refute that fA Q - t 1- is logically valid, although there is no general test for the validity of sentences of the form fA Q - t A. Actually, there are straightforward proofs of the consistency of Q. 6 It may well be that we can prove the consistency of our belief system, although we lack a general procedure for determining whether a given set of sentences is consistent or not. Thus consistency would be accessible in all relevant cases, but inaccessible in some others. Church's Theorem actually raises a problem for certain accounts of belief revision. There are accounts that describe how we should deal with new information as follows. Assume that S is the set of beliefs you have already acquired, and suppose further that there is a new input A. Now check first whether the new belief A is consistent with the old stock S of beliefs. If it is consistent, simply add A to the set S of old beliefs and you obtain the new belief system S U { A }, which incorporates A. If A is not consistent with the beliefs in S, then do something else. Many formal approaches to belief revision are concerned with this "something else". But here I am not interested in the problem of how our belief system can be revised in such a way that a new (consistent) belief set is obtained in the case that A is not consistent with S. Here I am interested in the earlier step where it is required to check whether A is consistent with S. Most formal ac-

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counts of belief revision deal only with propositional logic. Thus "consistency" is to be understood in terms of propositional logic. Since propositional logic is decidable, the check for consistency can be carried out in principle (although it may require fairly complex computations). But ifthis picture of how new beliefs are incorporated in our belief system is applied to predicate logic, a fundamental difficulty arises. Epistemic agents do not know how to obey the command "check first whether the new belief A is consistent with the old stock S of beliefs!" According to Church's Theorem, there is no general recursive method to carry out this check. So there might be a general problem for the applicability of formal accounts of belief revision. But I do not take it as a conclusive argument against the claim that consistency is not accessible in a sense relevant for epistemology.

2.3.

Godel's Second Theorem

It can be granted that consistency of very complex belief systems can be shown,

and that the complexity of truth tables and Church's Theorem do not contradict this observation. In fact, consistency proofs of even very strong systems can be very simple in terms of length of proofs. Thus, I conclude that the above arguments cannot disprove conclusively that consistency is accessible. Here is an interesting twist. What tools do we have at our disposal in order to establish the consistency of our belief system? Obviously, we must carry out the consistency proof of our belief system on the basis of what we believe, that is, on the basis of our belief system. For we can use in our reasoning only assumptions we already believe. The consistency of the belief system must be established within that very belief system. Godel's Second Incompleteness Theorem seems to tell us that such a consistency proof cannot work, according to the slogan "No system can prove its own consistency." So, proving consistency of one's belief system does not produce problems because the proofs are too complex or because there is no uniform procedure to check consistency, but rather because the resources for the proof are limited in the case we are interested in, namely where we try to prove consistency of a belief system within that very same belief system. In all interesting cases, the consistency of a belief system can only be established in a more comprehensive belief system, or so it seems. In the discussion of the argument based on Church's Theorem, I claimed that consistency proofs can be carried out although we lack a decision procedure for consistency. These consistency proofs, however, require means that go beyond the resources available in the system for which consistency is shown. The consistency of Peano Arithmetic, for instance, can easily be shown within set

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theory, or in Peano Arithmetic plus some additional principles like transfinite induction up to co, but not within Peano Arithmetic, or so it is claimed. I grant that G6del's Theorem on the unprovability of consistency poses the hardest challenge for consistency as an epistemically valuable criterion of coherence. However, the case is far from being clear because of some nontrivial metamathematical problems that have some bearing on the problem. As is well known, it is not so easy to state G6del's Second Theorem in a precise and general form. The slogan "No system can prove its own consistency" is at least misleading if not simply false. In this paper, I do not discuss all ins and outs ofG6del's Second Theorem. I will only mention some points that seem relevant to our discussion. In the first place, most formulations of G6del 's theorems pertain to arithmetical languages. In particular, consistency is expressed in this arithmetical language via some coding. Epistemologists, however, did not claim that coherence requires provability of certain arithmetical sentences that somehow 'express' consistency relative to some coding. Thus, if G6dels theorems are relevant at all, they must be generalized beyond the realm of arithmetical languages. Even if it is assumed that the belief system is entirely formulated in an arithmetical language, it is by no means clear that a system cannot prove its own consistency. I will hint at only a few well-known technical details. What is the consistency statement for a formal system S? Usually one provides a formula Bew (x) that represents (numerates) provability within the system. That is, Bew( n) is provable (relative to a system to be specified) if and only if n is the code of a formula provable in S (where n is a numeral for the number n). Then, the consistency statement is defined as -.Bew(#(O =I- 0)). However, there are many formulas representing provability in S. For some, G6del's Second Incompleteness Theorem holds; for others, it does not. There is a strong feeling among logicians that those consistency statements for which the second incompleteness theorem does not hold are somehow unnatural. But so far no-one has been able to give a clear account of 'naturalness.' Feferman (1960) has succeeded in providing certain technical conditions on Bew( x) that allow for a proof of the incompleteness theorem, but these conditions fall short of being 'natural.' Therefore, the second incompleteness theorem is inconclusive as an argument against consistency as a necessary condition for coherence. Popular simplified formulations of the second incompleteness theorem like "No system can prove its own consistency" may indeed pose a problem for somebody claiming that consistency is accessible to us. However, the mathematical facts do not support these formulations. Therefore, I believe that the burden of proof is with

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those who claim that consistency is not attainable because of Gbdel 's theorem; they have to provide versions of the theorem that yield their claim that consistency is not within our reach.

3.

CONCLUSION

I have shown that the arguments that are purported to prove that consistency is as little accessible to us as purely external facts are not conclusive. Of course, consistency is not accessible, if 'accessible' is understood in a very strong way, for we do not have general procedures for determining whether an arbitrary given set of sentences is consistent. But this kind of accessibility is not required for most epistemological purposes. For those purposes, we only need to establish the consistency of our own belief system or the consistency of our belief system with another belief. Although I have shown that the discussed arguments are not conclusive, I do not claim that consistency actually is accessible in a relevant sense. Church's Theorem and Gbdel's Second Theorem will make it hard to give a general account of how justification is obtained if consistency is to be used as a partial criterion for justification. The arena is open again. Acknowledgements. The paper was presented to the Belgian Society for Logic and Philosophy of Science, Brussels, Belgium, on 23 January 1999. The helpful suggestions of the audience are gratefully acknowledged. The work on this paper was carried out while the author was a member of the research group Logic in Philosophy financed by the Deutsche Forschungsgemeinschaft. I thank David McCarty and the members of the research group and, in particular, Erik Olsson for useful suggestions and discussions.

ENDNOTES 1 Moreover, these arguments have also been employed against extemalist coherence theories. See Komblith's (1989) attack on Hmman's (1973) theory. 2 After the quote below, Lehrer also discusses the prospects of working with inconsistent belief systems. 3 According to this quote, an inconsistent acceptance system does not justify any belief. In the more recent paper (1999), Lehrer explicitly maintains on p. 252 that beliefs can be justified on the basis of inconsistent belief systems. I quote another passage where he seems to suggest that inconsistency might not be fatal to our efforts to obtain justified beliefs. He writes in (l990a, p. 166):

Hence one who values consistency as an end in itself should recognize that a person with equally pure intellectual concerns may reasonably accept an inconsistent set of sentences. What he accepts may be suited to the objectives of obtaining new information and eschewing error.

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4 At this place it makes a difference how belief is defined. If, linguistically speaking, the limited performance of a subject is neglected and only his or her competence is considered, then a person may believe even very long sentences and in fact sentences of arbitrary length. However, if there is no limit imposed on the perfonnance of a subject, then there is no limit on the complexity of truth tables that can be calculated. 5 There is also another system called Robinson's arithmetic which is usually designated by R. 6 Just how valuable the consistency proofs for Q are is a different problem. In the light of Go del's Second Incompleteness Theorem, the value of these consistency proofs may be doubted. I will return to this point below.

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REFERENCES Bonjour, Laurence. 1985. The Structure C?f Empirical Knowledge. Cambridge, Massachusetts: Harvard University Press. Chemiak, Christopher. 1986. Minimal Rationality. Cambridge, Massachusetts: MIT Press. Feferman, Solomon. 1960. "Arithmetization of metamathematics in a general setting." Fundamenta Mathematicae XLIX:35-91. Harman, Gilbert. 1973. Thought. Princeton: Princeton University Press. Hooker, Cliff A. 1994. "Idealization, Naturalism, and Rationality: Some Lessons from Minimal Rationality." Synthese 99:181-231. Komblith, Hilary. 1989. "The Unattainability of Goherence." In The Current State C?fthe Coherence Theory, edited by John Bender, 207-214. Dordrecht: Kluwer. Lehrer, Keith. 1990a. "Reason and Consistency." In Metamind, 148-166. Oxford: Clarendon Press . .- - . 1990b. Theory of Knowledge. Boulder: Westview Press. - - - . 1991. "Reply to Mylan Engel." Grazer Philosophische Studien 40:131-133. - - - . 1999. "Justification, Coherence and Knowledge." Erkenntnis 50:243-258. Schlick, Moritz. 1934. "Uber das Fundament der Erkenntnis." Erkenntnis 4:79-99.

COHERENCE AND PERSONAL JUSTIFICATION

Chapter 6 REASONABLE ACCEPTANCE AND THE LOTTERY PARADOX: THE CASE FOR A MORE CREDULOUS CONSISTENCY Glenn Ross Franklin and Marshall College

In his formulation of coherentist theories of knowledge and epistemic justification, Keith Lehrer has often returned to the lottery paradox to draw important lessons. Some of these lessons are about knowledge. Lehrer has maintained that if a lottery has lots of tickets, only one of which will win, one cannot know, simply on probabilistic grounds, that any particular ticket will not win. Lehrer also defends a less obvious lesson: that it is not even reasonable to accept that one's ticket will not win. It is not clear, however, that Lehrer's theory of personal justification has this consequence. It is even less clear that it should. The lottery paradox for reasonable acceptance can be seen as a dilemma, and Lehrer's resolution amounts to swallowing a skeptical horn of that dilemma. Showing that this resolution is too skeptical requires that we canvas several similar approaches to the lottery paradox. Since I agree with Lehrer and Iikeminded philosophers that the other horn of the dilemma, an inconsistency resolution, is wholly unacceptable, I endorse slipping between the horns. Nonetheless, I find that there is much in Lehrer's general theory of reasonable acceptance that is congenial to my view.

1.

ADILEMMA

In a fair lottery with very many tickets, and only one winning ticket, I should be very confident that my ticket would lose. My reasons for being highly confident would seem to make it epistemically permissible for me to accept that 91 E.J. Olsson (ed.). The Epistemology of Keith Lehrer, 91-107. © 2003 Kluwer Academic Publishers.

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my ticket will lose. Yet, since my reasons for accepting that my ticket will lose are qualitatively identical to my reasons for accepting that any other ticket will lose, I do not have any epistemic reason to prefer accepting that my ticket will lose to accepting that some other ticket will lose. It seems epistemically wrong and arbitrary to accept that which I recognize I have no better reason for accepting than that which I choose not to accept. So, either I should not accept, of any ticket, that it will lose, or I should accept, of each and every ticket, that it wi\l lose. To refuse to accept of any ticket that it will lose in a very large lottery seems immoderately skeptical. To accept that a given ticket will lose is attractively less cautious. Yet, if it would be arbitrary and epistemically unreasonable to accept that one ticket will lose and not to accept the same of the other tickets, then one cannot accept of one ticket that it will lose without being obliged to accept the same of all the rest. If I accept of each ticket that it will lose, but also accept that some ticket will win, my acceptances will be selfrecognizably inconsistent. That seems just as bad. , Keith Lehrer 1 and many others (e.g., Mark Kaplan 2 , John Pollocko, Sharon Ryan4, and Dana K. Nelkin 5) adopt the epistemically cautious resolution and insist that considerations of consistency demand that one should uniformly withhold judgment on each proposition that a particular lottery ticket will lose. Richard Fole/ and Peter Klein7 opt for the much more credulous recommendation that one can be recognizably inconsistent: accepting of each ticket that it will lose while also accepting that some ticket will win. I propose that we can slip through the horns by adopting a consistently credulous approach 8 : one can rationally accept that one's ticket will lose, while not accepting that of many of the others, even though one is no less confident that they too willlose. 9 Both the skeptical and the inconsistency solutions presuppose a principle of symmetry: that if! have equally good reason to accept of any ticket that it will lose as I have to accept that any other ticket will lose, I should adopt the same attitude uniformly. I should either accept of each ticket that it will lose or not accept of any ticket that it will lose.

2.

LEHRER'S RESOLUTION: NEUTRALIZING THE COMPETITION

Lehrer accepts the principle of symmetry and argues that considerations of consistency show it is not reasonable to accept that any lottery ticket will lose. He then proceeds to show how he can get this result from his theory of rational acceptance. His theory involves a few technical terms that must first be defined.

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Lehrer analyzes personal justification in terms of coherence in an acceptance system. Whether a statement is reasonable to accept depends upon what statements compete with it. The notion of competition is defined as follows: c competes with p for S on the basis of the acceptance system of S at t if and only if it is less reasonable for S to accept that p on the assumption that c is true than on the assumption that c is false on the basis of the acceptance system of Sat t.10 Naturally, statements beat their competition for reasonab Ie acceptance when they are more reasonable to accept. p beats c for S on [the acceptance system of S] at t if and only if c competes with p for S [on the acceptance system of S] at t and it is

more reasonable for S to accept that p than to accept that c on [the acceptance system of S] at t. Lehrer provides a heuristic device to aid in our understanding of these conditions: a scenario in which a claimant to reasonable acceptance plays a game with a skeptic. In this justification game, the skeptic produces challenges that compete with the statements the claimant accepts. The claimant then responds to these challenges by defending her claims, for example, by showing that the competing claim can be beaten. If all the challenges raised by the skeptic are beaten, then the claimant wins the justification game and is personally justified. Claimant: I see a snake. Skeptic: You are dreaming you are seeing a snake. Claimant: It is more reasonable to accept that I see a snake than that I am dreaming that I am seeing a snake. The point of the game is not to refute the skeptic, but to exhibit those elements of one's acceptance system that justify the original claim. Still, a statement need not beat all of its competitors to merit reasonable acceptance. It is sufficient to neutralize the competition. The notion of neutralization is defined thusly: n neutralizes c as a competitor ofp for S on [the acceptance system of S] at t if and only if c competes with p for S on [the acceptance system of S] at t, but the conjunction of c and n does not compete with p for S on [the acceptance system of S] at t, and it is as reasonable for S to accept the conjunction of c and n as to accept c alone on [the acceptance system of S] at t.ll

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In the following justification game, a challenge is neutralized, not beaten: Claimant: I see a snake. Skeptic: People sometimes dream that they see snakes. Claimant: I am not now dreaming. The reason that the claimant's response neutralizes the skeptical challenge is that it is as reasonable to accept the conjunction that I am not now dreaming even though people sometimes dream that they see snakes as it is to accept that people sometimes dream that they see snakes. Though a conjunction is less probable than its conjunct, the additional informational content of a conjunction can make it as reasonable to accept as the conjunct inasmuch as it can have greater epistemic utility. Now we are in a position to consider how Lehrer utilizes his theory to handle the lottery paradox: The definition of justification given above, when combined with the formula for reasonable acceptance, yields the correct result that I am not justified in accepting that the number one ticket has not won. Consider the following move in the justification game: Claimant: The number one ticket has not won. Skeptic: The number two ticket has not won. The skeptic has produced a competitor to my claim because, by definition, c competes with p just in case it is more reasonable to accept that p on the assumption that c is false than on the assumption that c is true. If what she has claimed is false and the number two ticket has won, then my claim must be true. On the other hand, on the assumption that what she has claimed is true, the probability of my claim is reduced to 98/99 because the number of potential winners is reduced to 99. In this case, the utilities of accepting the two claims, the skeptic's, and mine are obviously the same, and, therefore, the comparative reasonableness of the two claims is the same. Consequently, the skeptic's claim is not beaten, it is as reasonable as mine, and it cannot be neutralized either. 12 The very last claim, however, demands an argument. Why should we think that the skeptic's claim could not be neutralized? Could it not be that the conjunctive claim that both the number one ticket and the number two ticket have not won, while less probable than the claim that the number one ticket has not won, is at least as reasonable in virtue of its additional informational content? It is not obvious that the rate of increase in the utility, as we conjoin these lottery

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statements, will never be as great as the rate of decrease in the probability. So, it is not obvious that the skeptic's objection cannot be neutralized. Whether or not Lehrer's theory is adequate to the task of giving him the result he seeks for resolving the lottery paradox, the fundamental question is whether he is seeking the right result. Do considerations of consistency preclude the rational acceptance of any lottery proposition? Let us turn to an argument that withholding on such lottery statements is analogous to withholding on many other statements about the future, statements that we have adequate inductive reasons to accept.

3.

AGAINST BOTH EXCESSIVE EPISTEMIC CAUTION AND RECOGNIZED INCONSISTENCY

The fact that my lottery ticket is very probably a loser constitutes a good reason for accepting that it will lose as long as merely probabilistic grounds can suffice for reasonable acceptance that my ticket is not going to win. Such probabilistic reasons are adequate for reasonable acceptance if lottery situations are analogous to situations in which one has merely probabilistic, but adequate, grounds for various empirical acceptances. There do seem to be many lotterylike empirical claims about that which is unobserved, where our evidence, though statistical, seems perfectly adequate for reasonable acceptance. Ifso, then by analogy, it can be reasonable to accept that one's lottery ticket will lose. Jonathan Vogel has suggested that lottery-like empirical statements abound. One is the proposition that a meteorite will not hit the place where I am sitting right now. I have no better reason to accept this than I have to accept of any other place of comparable size on the surface of the globe that a meteorite will not hit there at some particular time. Moreover, ifI consider a long enough span of time, I have high confidence that a meteorite will hit somewhere and sometime. Yet, even with no better reason to deny that the meteorite will now hit here than I have to deny that it will hit somewhere else at some other time, I confidently assert and accept that a meteorite will not hit me here and now. Likewise it is reasonable for me to accept that a satellite due to fall out of orbit will not hit my house, though pieces of it are expected to hit somewhere. Further, it is reasonable for me to accept that I will not be burned to death by a pyroclastic flow of hot ash from Mount Rainier while I spend a few days at a conference in Seattle, though I fully expect that eventually such events will occur around active volcanoes. I can reasonably accept an earthquake will not kill me during my next visit to Los Angeles, despite my having good reason to expect there will be such earthquakes, and resultant fatalities, sometime or other. 13 It would seem immoderately cautious and skeptical to deny that I can reasonably accept that a meteorite will not hit me, or that the satellite falling out

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of orbit will not hit my house, or that I will not be killed by a volcano while in Seattle or an earthquake while in Los Angeles. The skepticism will be extreme if we endorse a restricted principle of closure for reasonable acceptance. Suppose I am subject to epistemic criticism for failing to accept what I recognize to follow, in a deductively immediate manner, from that which I accept. Then, if it is unreasonable to accept that a meteorite will not imminently crush me, it is unreasonable to accept anything that entails this negative fact, including any fact about my future life. Yet, even if we do not accept such a limited principle of closure, it still seems immoderately skeptical and cautious to maintain that an epistemically scrupulous individual should refrain from accepting that a meteorite will not hit here and now, despite reasons that should make one highly confident that this proposition is true. Yet we should also not follow Foley and Klein and contend that it is rational to accept of each ticket that it will lose, despite the recognition that these acceptances are not logically compatible with accepting that one of the tickets will win. We should resist this position, as Kaplan and Pollock have argued, because if recognized inconsistency does not leave one vulnerable to epistemic criticism, then there is no dialectical point in providing a reductio ad absurdum of someone else's position. That reductios do have epistemic weight shows that recognized inconsistency is an epistemological vice.

4.

IS THE LOTTERY CASE RELEVANTLY UNIQUE?

It is incumbent on those who reject the above argument from analogy, who think we can rationally accept that we will survive the next five minutes but not that our lottery ticket will lose, to try to find some relevant disanalogy to distinguish the lotter~ and the lottery-like cases. Keith DeRose 4 offers an interesting proposal when considering what differences might account for why a lottery-like proposition is knowable or assertible while a lottery proposition is not. Since it is plausible to connect what is assertible with what is rational to accept, one might think that his proposals could plausibly carry over to our problem and provide those wishing to reject the analogical argument with a relevant disanalogy. DeRose considers a case in which I accept that the Bulls won last night despite the fact that I know that the paper sometimes misprints the scores. I have no better reason to think the Bulls won than I have when I read a misprinted score that has them winning when they did not. DeRose perceives a difference between this case and that of the lottery in the truth-values of corresponding counterfactuals. In the lottery case, but not the score-reading case, I would have accepted the relevant claim even had it been false. That is, I would accept that my ticket would lose, even if my ticket were to be the one that will win. On the

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other hand, it is false that I would still accept that the Bulls had won even ifthey had not. For, had the Bulls not won, I very well might have read an accurate newspaper account of the game and consequently have accepted that they did not win. 15 Yet, whether an accepted statement passes or fails DeRose's subjunctive conditional test cannot make the difference between whether or not it is rational to accept it. Consider a revised newspaper case proposed by DeRose, in which one knows that each day there is one, and only one, copy of the newspaper in which all of the sports scores are inverted. Using DeRose's criterion as a requirement for rational acceptance on this case yields the consequence that one can rationally accept that the Bulls won on the basis of the reported score in the paper. Yet, one cannot rationally accept that one's paper is not the defective copy. Nonetheless, one's grounds for accepting that the Bulls won is the score that is reported in one's copy of the paper. It would seem that if one cannot reasonably accept that one does not have a non-defective paper, and one recognizes that fact, then one cannot reasonably accept that the Bulls won. Since it is epistemically reasonable to accept in these circumstances that the Bulls won, I conclude that DeRose's test, though possibly demarcating cases of knowledge and assertibility, will not work as a criterion for demarcating cases of rational acceptance. Another unique feature of the lottery case that might be exploited to provide a disanalogy with the lottery-like cases is the fact that in the lottery case one knows that there is a winning ticket. Since one knows that there is a winning ticket of the lottery, one knows that there is some objective probability of one's winning. So one might contend that though it may be reasonable to accept that one will probably lose, it is not reasonable to accept that one will lose. On the other hand, despite the probability that not all parts of the satellite will burn up before reaching the earth's surface, one cannot take it for granted that some parts will reach the ground. 16 Since one does not know that any parts of the satellite will hit the ground, one cannot be certain that there is any objective probability of my house being hit. So, perhaps this difference could allow one to claim that in the lottery case, one cannot rationally accept that one's ticket is a loser, while in the case of the satellite, one can reasonably accept that one's house will not be hit. That this disanalogy is not adequate to the task at hand is apparent, however, if we consider a revised lottery case. Suppose that one ticket among the million or so tickets is designated the "No Winner" ticket and is assigned to no one, so that if that ticket is selected, no ticket wins. If it is reasonable for you to accept that the satellite will not hit your house because you cannot be sure that any part of the satellite will crash anywhere, then it is similarly reasonable for me to accept that my ticket is not a winner. For, one cannot take it for granted that any ticket is a winner, and it is very unlikely that any particular ticket will win. Yet, since one knows that one ticket will be selected, then according to this line,

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it is still unreasonable for me to accept that my ticket was not selected. So, I can reasonably accept that my ticket will lose, but not reasonably accept that it was not selected. This cannot be right. For, I know, by an immediate inference, that if my ticket is not the winner then it was not selected, since I know that it is not the No Winner ticket. So, if it is reasonable to accept that my ticket will lose, then it is reasonable to accept that my ticket was not selected. It follows, that whether or not I know that some lottery ticket will lose cannot matter in the reasonability of accepting whether a particular ticket will lose. Good analogies cut both ways. If you are convinced you do not have good reason to accept that your lottery ticket is a loser, you could use the analogy to lottery-like cases to argue that you similarly have no good reason to accept that your house will fail to be hit by the satellite. Dana K Nelkin, in seeking to find a difference between lottery situations and cases in which inductive reasoning based on perception is justified, argues that the feature of lottery inferences that makes them epistemically unjustified lies precisely in the purely statistical nature of the evidence. Thus, on Nelkin's account, there is no difference between the lottery situations and the lottery-like situations, so long as one's evidence in both cases is purely statistical. Nelkin argues that statistical inferences are only acceptable when grounded in presuppositions of a causal explanation of the statistical evidence. The intuitive costs of this account are evident when Nelkin considers a case proposed by Gilbert Harman. I? If Mary will be in Trenton only if she wins the lottery, and in New York otherwise, then if one cannot rationally accept that Mary will not win the lottery, it would seem that one could not rationally accept that Mary will be in New York. Nelkin responds by conceding this implausible consequence, and responds that such situations are relatively rare. Nelkin's position is immoderately skeptical. If it is not rationally permissible to accept that your house will not be hit by a satellite or a meteorite, on purely statistical grounds, then if a limited closure of recognized immediate inferences holds, then it would seem to be correspondingly impermissible to accept that which presupposes that we will not be hit by a meteorite, and then it is difficult to imagine much of anything in our future about which one could form a reasonable expectation. Moreover, even if limited closure fails, apparently justified statistical inferences are not all that rare, and not confined to the future. If you were to tell me that you randomly flipped twenty heads in a row yesterday. I would infer that you were flipping for a long time. I do so on the basis of statistical considerations, and not because I accept that there is a causal connection between flipping a coin for a long time and getting twenty heads in a row. It would seem that such purely statistical inferences are both common and reasonable. Using a generalization of Keith Lehrer's Racehorse Paradox,18 John Pollock has provided a technical argument to show how one can turn any statistical syllogistic inference from high probability into a lottery-like form. 19

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Since Pollock incorporates a principle of symmetry into his analysis of the lottery to show that any lottery inference to accepting that any particular ticket will lose is "collectively defeated," and thus unreasonable, he needs some difference between lottery situations and lottery-like situations to avoid immoderate inductive skepticism. He suggests that the difference lies in the projectibility or non-projectibility of disjunctive predicates. Nonetheless, he admits that this is only to label the difference, and not to provide an account of it, since projectibility is understood in terms of which inferences are epistemically acceptable to draw. 20 Moreover to adopt his analysis of the lottery case in terms of "collective defeat" would be to presuppose the very issue at stake in this paper: the principle of symmetry. Absent any other account of why we have reasonable acceptance in the case of the meteorites, earthquakes, and volcanoes, but not in the case of the lottery, the lottery and the lottery-like cases would seem analogous. It is epistemically reasonable for me to accept that my lottery ticket will lose, just as it is epistemically reasonable for you to accept that a satellite will not hit your house tonight.

5.

SLIPPING THROUGH THE HORNS

Both horns of the lottery dilemma presuppose the symmetry principle: If we have no better reason to accept a statement than to accept another, then our attitude toward each should be the same. We should either accept both or accept neither. Symmetry Principle (for Reasonable Acceptance): If S recognizes at t that p and q are equally reasonable for S to accept at t on the basis of the acceptance system of Sat t then it is reasonable for S to accept that p at t on the basis of the acceptance system of S at t only if it is reasonable for S both to accept that p and to accept that q on the basis of the acceptance system of S at t. In the lottery, this throws us back onto our two horns: either we do not accept of any particular ticket that it will lose, or we accept of all tickets that they will lose despite our recognizing the inconsistency with our accepting that some ticket will win. Gilbert Harman considers a via media: ... To say one can infer this of any ticket is not to say one can infer it of all. Given that one has inferred ticket number 1 will not win, then one must suppose the odds against ticket number 2 are no longer 999,999 to 1, but only 999,998 to 1. And after one infers

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THE LOTTERY PARADOX ticket number 2 won't win, one must change the odds on ticket number 3 to 999,997 to 1, and so on. If one could get to ticket number 999,999, one would have to suppose the odds were even, 1 to 1, so at that point the hypothesis that this ticket will not win would be no better than the hypothesis that it will win, and one could infer no further. (Presumably one would have to have stopped before this point.)21

There is thus no inconsistency in accepting that some tickets will lose while not accepting that of others. Yet, that is not to say that such arbitrary choices are epistemically reasonable. Indeed, they will not be, if the symmetry principle holds. Harman seems to endorse a symmetry principle for epistemic acceptance, for he takes non-arbitrariness to be a mark that distinguishes theoretical from practical choices: Theoretical and practical reasoning differ in this respect. In practical reasoning one can be justified in satisficing even in choosing among competing plans at the same level. In fact, often this is just what one should do-make an arbitrary choice of a satisfactory plan to accomplish one's goals. But in theoretical reasoning one would not be justified in making an arbitrary choice of what to believe among competing hypotheses at the same level. 22 John Pollock maintains that confusion between practical and epistemic reasoning underlies any temptation to give up a symmetry principle: The preceding considerations suggest that the controversy over skeptical and credulous reasoning stems from a confusion of epistemic reasoning (reasoning about what to believe) with practical reasoning (reasoning about what to do). In practical reasoning, if one has no basis for choosing between two alternative plans, one should choose at random. The classical illustration of this is the medieval tale of Buridan's ass who starved to death standing midway between two equally succulent bales of hay because he could not decide from which to eat. This marks an important difference between practical reasoning and epistemic reasoning. An agent making practical decisions must first decide what to believe and then use that in deciding what to do, but these are two different matters. If the evidence favoring two alternative hypotheses is equally good, the agent should record that fact and withhold belief.23

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In arguing against the acceptability of reasoning in the credulous manner described by Harman, Dana Nelkin elides this sharp distinction between practical and theoretical reasoning and offers a pragmatic consideration in defense of symmetry: Suppose, with Harman, that Jim can rationally infer that t1 through t999,000, say, will lose. Jim is also rational in believing that one of t1 through 1,000,000 will not lose. It would seem to follow that Jim could rationally infer a logical consequence of these beliefs, namely, that one oft999,001-tl,000,000 will not lose. But this is strongly counterintuitive. If Jim were rational in believing that one of those 1,000 tickets will win, then, depending on the order of his inferences, he should either try to get his hands on one of those 1,000 tickets or feel fortunate to be holding one of them already! But there is no reason for Jim to do either of these things. Thus, Harman's argument fails ... 24 Plausibly, a rejection of the principle of symmetry should not provide this much license. For one could reject symmetry, and accept of several tickets that they will lose without practicing a form of epistemic brinksmanship and accepting that all but a particular 1,000 will lose. More importantly, however, it is to misunderstand the acceptance system of such a reasoner to think that there need be any acceptance of a proposition to the effect that the tickets one accepts to be losers are objectively different from the tickets one does not accept to be losers. Obviously, not to accept that a ticket will lose is not to accept that it will not lose. Less obviously, not to accept that a ticket will lose is not to have less confidence that it will lose. To treat the difference between accepting that one lottery ticket will lose and not accepting that another will lose as implying a distinction in the reasons for accepting that the one or the other will lose, i.e., in the comparative confidence levels one has that one or the other will lose, is tantamount to presupposing the symmetry principle itselfl Let us return, then, to the charge that to defend the reasonability of rejecting the symmetry principle is to confuse pragmatic and epistemic reasons. Can such arbitrariness be justified only pragmatically and never epistemically? The answer depends on the nature of epistemic justification. Those who take a deontological approach to epistemic normativity might insist that the principle of symmetry has a priori plausibility.25 It is less clear why those who take a more consequentialist approach to epistemic justification should be similarly moved to accept symmetry at the price of foregoing the chance to accept highly probable and plausible lottery propositions (and perhaps also lottery-like propositions). It is a familiar theme of Keith Lehrer's work on epistemic acceptability that "the goal of acceptance

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is to obtain truth and avoid error.,,26 If truth is our ultimate aim, why can we not have purely epistemic reasons to reject symmetry and accept some lottery propositions? Are there philosophers who question symmetry for what appear to be purely epistemological reasons? It would seem so. In "Sellars on Induction Reconsidered," Lehrer displays a new interpretation of Wilfrid Sellars's view of empirical acceptance rules, a view that violates a non-arbitrariness condition that is implied by the Symmetry Principle. Here is how Lehrer describes Sellars's view: If one is only concerned with getting a maximum of true observation statements, then it is reasonable to accept all of the statements' a] is B,' 'a2is B,' and so forth to 'a" is B.' In the interest of accepting true observation statements, this policy is warranted when the probability that an a] is B is greater than 112. But, and this is the heart of the new interpretation, such acceptance is only prima facie reasonable. When we ask, not what is prima facie reasonable, but what is reasonable sans phrase, the answer will be different. For then we must be concerned, not only with accepting as many true observation statements as possible, but also with maintaining coherence among statements of different types, for example, observation statements and generalizations about the population, and this will preclude us from accepting all the observation statements mentioned so as to avoid inconsistency. Thus, according to the new interpretation, this way to combine the objectives of accepting true observation statements and at the same time maintaining explanatory coherence is to accept the percentage ofthe observation statements, provided it is greater than 50%, that corresponds to the percentage of members ofK that are known to be B in the total population. For example, if we know that 3/4 K are Band K satisfies the pertinent relevance conditions, then we accept 75% of the statements of the form' a] is B. ,27 While Lehrer maintains his own commitment to symmetry, he does allow that Sellars's position is "justified by systematic epistemic objectives and is in no way ad hoc ... ,,28 I agree. Sellars's position demonstrates that rejection of symmetry can be grounded in purely epistemological, not pragmatic, considerations. In rejecting symmetry, we need not endorse a position akin to Sellars's. If we did, we would license accepting of all but one ticket that it lose! That is obviously too permissive. Yet, is there not good reason to accept of a few tickets that they will lose, while not getting carried away? The only barrier in our way is the Symmetry Principle.

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Yet, if it is permissible to accept of any lottery ticket that it will lose, is it not permissible to accept that they all are losers? If this is not just another appeal to the Symmetry Principle, then there is a confusion underlying the question. Permissibility is not adjunctive. I may be permitted to have any fruit in the fruit basket but not be permitted to have them all. My being permitted to have the pear may depend upon whether I have already exercised my permission to have the banana. Similarly, what is reasonable to accept is contingent on what is already accepted. Since Lehrer's analysis of personal justification does not presuppose the Symmetry Principle, it has the flexibility to provide an analysis of personal justification for the more credulous reasoner. This, by my lights, is a virtue of his analysis. 29 To see how we can use Lehrer's analysis for less skeptical purposes, consider again the justification game, this time played between a skeptic and a credulous reasoner: Claimant: The number one ticket has not won. Skeptic: The number two ticket has not won. Claimant: It is as reasonable for me to accept both that the number two ticket has not won and that the number one ticket has not won as to accept the former alone. (While the conjunction is less probable than either conjunct, the added informational content outweighs the negligible additional risk of error.) The claimant has won this round by neutralizing the skeptic's challenge. The claimant's original claim, 'The number one ticket has not won', neutralizes the skeptic's challenge, inasmuch as the conjunction of their two claims is at least as reasonable as the claimant's original claim. Of course it could happen that this conjunction of the objection with the original claim does not neutralize the objection. This will happen if the increase in informational content due to conjoining does not outweigh the decrease in probability. For example, if the lottery is not very large, then the probability of these two tickets losing could be substantially less than the probability of one ticket losing. In a three-ticket lottery, the probability is thereby halved. It follows that in a small lottery one is not personally justified in accepting that one holds a losing ticket. That is as it should be. The game could continue with the claimant winning round after round by neutralizing the opposition: Claimant: The number one ticket has not won. Skeptic: The number two and number three tickets have not won. Claimant: It is as reasonable for me to accept that the tickets numbered one, two and three have not won as to accept just that the number one ticket has won. (While the conjunction is less probable

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THE LOTTERY PARADOX than either conjunct, the added informational content outweighs the negligible additional risk of error.)

For some large n, the increase in informational content gained by accepting that every ticket among the n tickets will lose is offset by the corresponding decreased probability. Consider this continuation of the game: Skeptic: The number two through number n tickets (for some large n) have not won. Claimant: It is more reasonable for me to accept that the number one ticket has not won than to accept that the number two through n tickets have not won. The claimant wins this round by beating the skeptic's challenge. What happens in the transition from neutralizing to beating? Suppose the expected utility of accepting that ticket one will lose is equal to the expected utility of accepting that tickets one through m will lose. Suppose further that the skeptic attempts the following objection: Skeptic: The number two through m tickets have not won. On our first supposition, it is no less reasonable to accept that ticket one will lose on the assumption that ticket two through m will all lose than on the assumption that they will not all lose. Consequently, this objection of the skeptic does not compete with the original claim and is thus not a legal move for the skeptic in the justification game. We might worry about what happens on precise boundaries. We should not. Given the limitations of human reasoners to make very fine epistemic distinctions, the supposition of one ticket's losing will only make the relevant epistemic difference if the lottery is too small for one to reasonably accept that a particular ticket will lose. In a very large lottery, if we can successfully judge that an objection by the skeptic is indeed a competitor, then we will be able to neutralize or beat it. If one cannot judge whether an objection competes, then it should not defeat one's personal justification. 30 Notice that up to this point, the Symmetry Principle has not come into play. So, let us consider these moves: Skeptic: You do not accept that the number two ticket has not won but you have no better reason to accept that the number one ticket has not won. Claimant: The Symmetry Principle is false.

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So long as the claimant is personally justified in rejecting the Symmetry Principle, the claimant has successfully neutralized the skeptic's last challenge. There are good theoretical reasons to reject the Symmetry Principle. We accept in order to gain truth and avoid error. Basing acceptance on purely statistical grounds can be epistemically reasonable when the prospects for gain are great and the risks of loss small. A concomitant commitment to coherence provides the epistemological basis for our avoiding recognized inconsistency. Thus, I commend a position of credulous consistency as the most plausible of the three resolutions of the lottery paradox for reasonable acceptance. The lesson of the lottery is that we can sometimes have no better reason to accept, but reason enough.

ENDNOTES I Keith Lehrer, Metamind, Oxford, Clarendon Press, 1990, pp. 235-6 and Theory of Knowledge, Boulder: Westview Press, 1990, pp. 129-30. 2 Mark Kaplan, "Believing the Improbable, " Philosophical Studies 77 (1995), pp. 117-46, particularly pp. 136-7 and Decision Theory as Philosophy, Cambridge: Cambridge University, 1996, pp. 139-40. lJohn Pollock, Cognitive Carpentry: a Blueprintfor How to Build a Person, Cambridge, Mass.: MIT/Bradford, 1995, chapter 2. 4Sharon Ryan, 'The Epistemic Virtues of Consistency," Synthese 109 (1996), pp. 121-41, particularly p. 126. Ryan is working with a strong notion of justified belie( i. e., whatever justification knowledge requires. In the lottery paradox I am considering, the relevant concept of justification ranges from a weak notion of epistemic rational permissibility to a concept of justification no stronger than Lehrer's notion of personal justification. S DanaK. Nelkin, "The Lottery Paradox, Knowledge, and Rationality," Philosophical Review 109 (2000) pp. 373-409. 6Richard Foley, Working Without a Net, New York: Oxford, 1993, pp. 164-5. 7Peter Klein, "The Virtues of Inconsistency," Monist 68 (1985), pp. 105-35, particularly p 108. Note that Klein, like Ryan, is presuming a notion ofjustified beliefthat is required for knowledge. R I borrow the labels' skeptical' and 'credu lous' for the two positions one can take on symmetry from John Pollock, "Justification and Defeat," Artificial Intelligence 67 (1994), 377-407, who in turn acknowledges borrowing from D. S. Touretzky, J. F. Horty, and R. H. Thomason, who speak of credulous and skeptical reasoners. 9 Bayesians who reject the notion of acceptance in favor of quantitative measures of confidence would reject all three positions. I will not rehearse the standard replies to such Bayesians. 10 Theory of Knowledge, p. 118. II Theory of Knowledge, p. 125. These definitions of competition, neutralization, and personal justification are essentially preserved in Lehrer, Self Trust: A Study of Reason, Knowledge, and Autonomy, Oxford: Clarendon Press, 1997, p. 30. 12 Theory of Knowledge, p. 130. 13 See Jonathan Vogel in "Are There Counterexamples to the Closure Principle':>" in Doubting, Michael D. Roth and Glenn Ross (eds.), pp. 13-27, for several such cases where we would ordinarily claim to have knowledge though they appear to be analogous to lottery situations. 14 Keith DeRose, "Knowledge, Assertion and Lotteries," Australasian Journal of Philosophy 74 (1996) pp. 568-580.

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15 For this account to succeed, we must reject Robert Stalnaker's principle of conditional excluded middle for counterfactuals. 16 It is just this disanalogy that Sharon Ryan exploits in (1996). 17 Gilbert Harman, Change in View: Principles 0/ Reasoning, Cambridge, Massachusetts: Bradford/MIT, 1986, p. 71. 18 Keith Lehrer, "Coherence and the Racehorse Paradox," Midwest Studies in Philosophy, (1980) 5, pp. 183-192. 19 John L. Pollock, "How to Use Probabilities in Reasoning," Philosophical Studies 64 (1991), pp. 65-85. Also see Pollock's "A Solution to the Problem ofInduction," Noiis 18 (1984), pp. 423-461 and "Justification and Defeat," Artificial Intelligence 67 (1994), pp. 377-407. 20 Pollock (1991), pp. 80-1. 21 Change in View, p. 71. 22 Change in View, p. 68. 23 Pollock (1994), p. 383. 24 Nelkin (2000), pp. 377-8. 25 Epistemological deontologists might also demur from such a defense of symmetry, seeing considerations of high probability and coherent acceptance as trumping aprima/acie reasonability behind symmetry. 26 Theory o/Knowledge, p. 121. 27 Lehrer (1983), p. 471. 28 Lehrer (1983), p. 469. 29 Note that this flexibility to accommodate more credulous intuitions on the lottery is not shared by Pollock's (1994) notion of justification, inasmuch as his "Principle of Collective Defeat" (p. 383) incorporates a symmetry principle. 30 The argument can be fully spelled out as follows: Suppose the skeptic offers this challenge: Skeptic: The number two through m tickets have not won. There are three cases to consider: (a) The expected epistemic utility of accepting that ticket one will lose is less than the expected epistemic utility of accepting that all of the tickets one through m will lose. In this case, the statement that ticket number one will lose neutralizes the challenge, as in the first two rounds above. (b) The expected epistemic utility of accepting that ticket one will lose is equal to the expected epistemic utility of accepting that all of the tickets 1 through m will lose. In this case, the statement that tickets numbered two through m will all lose does not compete with the original claim ofthe claimant. It is no less reasonable to accept that ticket one will lose on the assumption that ticket two through m will all lose than on the assumption that they will not all lose. ©) The expected epistemic utility of accepting that ticket one will lose is greater than the expected epistemic utility of accepting that tickets one through m will lose. There are two sub-cases: (c-i) The expected utility of accepting that ticket one will lose is greater than the expected epistemic utility of accepting that tickets two through m will lose. In this case, the statement that ticket number one will lose beats the challenge, as in the above case for large n. (c-ii) The expected utility of accepting that ticket one will lose is less than or equal to the expected utility of accepting that tickets two through m will lose. Given the limitations in our abilities to make fine discriminations in the expected utility for the acceptance of statements, these cases will not arise unless the lottery is small enough for one ticket to make such a difference. So, in a very large lottery, these cases will not arise for human reasoners. If we can successfully

GLENN ROSS judge that an objection by the skeptic is indeed a competitor, then we will be able to neutralize or beat it. If we cannot judge whether an objection competes, then it does not defeat our personal justification.

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Chapter 7 RELATIONAL COHERENCE AND CUMULATIVE REASONING Charles B. Cross* University of Georgia

According to Keith Lehrer's (1974, 1986, 1988, and 2000) theory of knowledge, coherence is the basis of epistemic justification. In Lehrer's theory, coherence is a relation between a proposition and what Lehrer (2000: 170) defines as an evaluation system: D 1. A system X is an evaluation system of S if and only if X contains (a) states expressed by statements of the form, 'S accepts that p', attributing to S just those things that S accepts with the objective of accepting that p if and only if p (the acceptance system of S), (b) states expressed by statements of the form, 'S prefers accepting p to accepting q', attributing to S just those things that S prefers accepting with the same objective concerning acceptance, (the preference system of S), and (c) states expressed by statements of the form, 'S reasons from p, q, r, and so forth to conclusion c', attributing to S just those states of reasoning with the objective of being sound (having true premises and being valid). Based on the notion of an evaluation system, Lehrer (2000: 170) defines justification in terms of coherence as follows: D2. S is justified in accepting p at t on system X of S at t if and only if p coheres with X of S at t. Now, to the question, "What conclusions should one draw from the propositions one accepts?" it would seem sensible to answer, "One should draw those conclusions whose acceptance would be justified on the basis of what one accepts." 109 E.J. Olsson (ed.), The Epistemology of Keith Lehrer, 109-127. © 2003 Kluwer Academic Publishers.

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But if this is right, then Lehrer's account of justification should be interpretable not only as a theory of justification but as a theory of inductive inference, too. In what follows I shall investigate the consequences of interpreting Lehrer's account of system-relative justification as a theory of inductive inference. In Section 1, I set out Lehrer's theory of coherence. In Section 2, I present the elements of the theory of cumulative reasoning, I a widely known and well workedout proof theory for inductive reasoning. In Section 3, I formulate a definition of inductive inference in terms of a simplified version of Lehrer's analysis of coherence, and I discuss what assumptions about coherence would be sufficient to make the account of inductive inference derivable from his theory of justification conform to a series of widely discussed general principles, including those constitutive of cumulative reasoning. In Section 4, I consider the epistemological significance of the theory of inductive reasoning developed in Section 3.

1.

LEHRER'S THEORY OF COHERENCE

Having defined justification in terms of coherence, Lehrer (2000: 170) fleshes out the notion of coherence in the following reformulation of D2: D3. S is justified in accepting pat t on system X of Sat t if and only if all objections to p are answered or neutralized for S on X at t. Thus, on Lehrer's account, p coheres with X of Sat t if and only if all objections to p are answered or neutralized for S on X at t. Lehrer (2000: 170) defines the notions of objection, answering, and neutralizing as follows: D4.

0 is an objection to p for S on X at t if and only if it is more reasonable for S to accept that p on the assumption that 0 is false than on the assumption that 0 is true, on X at t.

D5. An objection 0 to p is answered for S on X at t if and only if 0 is an objection to p for S on X at t, and it is more reasonable for S to accept p than to accept 0 on X at t. D6. n neutralizes 0 as an objection to p for S on X at t if and only if o is an objection to p for S on X at t, the conjunction of 0 and n is not an objection to p for S on X at t, and it is as reasonable for S to accept the conjunction of 0 and n as to accept 0 alone on X at t. D4, D5, and D6 appeal to an undefined notion of relative reasonableness that Lehrer takes as primitive. 2 The following example, which adapts the example in Lehrer 1988:342 to Lehrer's (2000) new terminology, applies this notion of reasonableness in an illustration of D5.

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Wendy tells Keith that Fred Feldman's book is now in print. Is Keith justified in believing this? Keith's background information includes that he edits a series in which the book appears and that Wendy works for the publisher and is trustworthy about when books appear in the series. Now suppose that some skeptic proposes to Keith that Wendy is lying. The claim that Wendy is lying is an objection to the claim that the book is in print, but, on the basis of Keith's background information, it is more reasonable for Keith to accept that Wendy is telling the truth and that the book has been published than to accept that Wendy is lying. In this example, the claim Wendy is lying is an objection to the claim Feldman's book is in print because it is more reasonable for the subject to accept Feldman's book is in print on the assumption Wendy is not lying than on the assumption Wendy is lying. Since it is more reasonable for the subject to accept The book has been published than to accept Wendy is lying, the claim Feldman's book is in print answers the objection Wendy is lying. But is every objection to Feldman's book is in print answered? Consider this example, again adapted (with updated terminology) from the example in Lehrer 1988:342: Imagine the skeptic persists and says, "Well, you know people sometimes lie about when books are in print." Now this skeptical innuendo does count as an objection to the claim Keith believes in a sort of indirect way. It would be more reasonable for Keith to accept that Feldman's book is in print on the assumption that people do not ever lie about when books are in print than on the assumption that they do sometimes lie. Moreover, it is quite reasonable for Keith to accept that people do sometimes lie about these matters. But this skeptical innuendo, though it cannot be answered, can be neutralized by conjoining the reply that Wendy is not lying. Of course, the reasonableness of accepting the latter depends on Keith's background information about Wendy. The claim Wendy is not lying neutralizes the claim People sometimes lie about when books are in print as an objection to Feldman's book is in print because People sometimes lie about when books are in print, but Wendy is not lying is not an objection to Feldman's book is in print, and because it is as reasonable to accept People sometimes lie, but Wendy is not lying as to accept People sometimes lie by itself, given the subject's background evaluation system. If every objection to Feldman's book is in print is either answered (like the claim Wendy is lying) or neutralized (like the claim People sometimes lie about when books

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are in print), then the subject is justified in accepting that Feldman's book is in print. This example illustrates how natural it would be to interpret Lehrer's necessary and sufficient condition for justification relative to an evaluation system as a sufficient condition for the permissibility of an inference. The subject Keith in the previous example who asks, "Am I justified in believing that Feldman's book is in print?", may be using certain background information and skeptical alternatives to evaluate the epistemological status of a belief he already holds, or he may be considering whether to accept Feldman's book is in print as a new belief on the basis of that background information. But to consider whether to accept a given claim on the basis of given background information is to consider whether to infer that claim from the background information. This would be an inductive inference, of course, since the claim Feldman's book is in print does not follow deductively from the subject's background information, but the fact that the subject would be justified in believing this claim surely indicates that it would be a good inductive inference. What are the consequences of reinterpreting Lehrer's account of justification relative to an evaluation system as an account of inductive inference? In order to answer this question we will first need an introduction to the theory of inductive inference in its most general form: the theory of cumulative reasoning.

2.

CUMULATIVE REASONING

Systems of deductive inference (for example, classical first-order logic) satisfy three well-known conditions often labeled Reflexivity, Monotonicity, and Cut 3 Reflexivity If p E X then X f- p. Monotonicity If X f- p and X r;;:; Y, then Y f- p. Cut If X U {p} f- q and X f- p then X f- q. But most of the reasoning subjects actually do on a day-to-day basis (such as inference to the best explanation) is inductive. Despite its nondeductive character, it is possible to theorize in a proof-theoretic way about inductive reasoning, and formal approaches to inductive reasoning abound in the artificial intelligence literature. 4 Formally, the most conspicuous way in which inductive inference differs from deductive inference is the fact that inductive inference is nonmonotonic. Where 'X ~ p' means that p is an inductive consequence of X (under some given conception of inductive inference represented by '~'), it is possible for it to be the case that X ~ p and X r;;:; Y even though Y If p. For example,

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let X, Y, andp be the following:

= {'This match was struck', 'Oxygen was present'}, Y = X U {'This match was wet when struck'}, X

p = 'This match lit'.

Knowing that the match was struck and that oxygen was present, we can reasonably infer that the match lit. But if our evidence is expanded to include information that the match was wet, then the inference to the conclusion that the match lit is not licensed given the expanded evidence. If in the above list of conditions Monotonicity is replaced by the weaker condition of Cautious Monotony, the result is a version of what Gabbay (1985) calls cumulative inference: Reflexivity If p E X then X ~ p. Cautious Monotony If X ~ p and X ~ q, then X U {p} ~ q. Cut If Xu {p} ~ q and X ~ p then X ~ q. Makinson (1989) and Kraus, Lehmann, and Magidor (1990) present semantical approaches to cumulative inference based in part on Shoham's (1988) notion of preferential entailment. By investigating how Lehrer's notion of relational coherence can be interpreted as an account of inductive reasoning we will be developing an alternative to the received preferential model semantics for cumulative inference.

3. 'p COHERES WITH X' AS A SPECIES OF CUMULATIVE INFERENCE In our application of Lehrer's conception of justification below we will assume that the time variable t and epistemic subject variable S are fixed and so can be dropped. Since in the context of inference-making what will matter about an evaluation system is the set of propositions accepted in the acceptance system component, we will depart from Lehrer's use of the variable X. Specifically, instead of assuming that X represents a triple consisting of an acceptance system, a preference system, and a reasoning system, we will assume that X represents the sentences which formulate the claims that are accepted in the acceptance system component of an evaluation system. In other words, X will range over the sets of sentences expressing the p's that S accepts in a range of possible

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evaluation systems associated with some fixed S and t. Now, different evaluation systems in Lehrer's theory can share the same acceptance system, hence a subject's evaluation system at a given time is not strictly a function of his or her acceptance system. But in the coherence-based theory of inductive consequence to be explored below, the inductive consequences associated with a given evaluation system will be a function of the acceptance system component alone. Accordingly, the theory of inductive reasoning presented below may appear to assume that a subject's reasoning and preference systems are a function of his or her acceptance system. How can this be reconciled with the spirit of Lehrer's theory? The conflict is only apparent. When two evaluation systems incorporate the same acceptance system but not the same preference and reasoning systems, this means that the two evaluation systems in question are associated with different relations of comparative reasonableness relative to the given acceptance system. In the theory of inductive consequence developed below, the inductive consequences of X are determined in part by comparative reasonableness relative to X. When two evaluation systems incorporate the same acceptance system but not the same preference and reasoning systems, this means that the two evaluation systems in question are associated with different notions of inductive consequence. Lehrer's theory of evaluation systems is therefore, potentially, a theory of the dynamics of the inductive inference concept-a theory of inductive logic revision. We shall not offer a dynamic theory here. The theory to be presented below will concern the statics of coherence-based inductive inference. Since we are taking the variables S and t as fixed, Lehrer's seven-place relation of comparative reasonableness ("it is more reasonable for S to accept that p on the assumption that q than to accept r on the assumption that s on the basis of X at t") will become a five-place relation ("it is more reasonable to accept p on the assumption q than to accept r on the assumption s on the basis of X,,).5 These modifications allow us to define 'X ~ p' as in C1 below and work with C2-C6 instead of Lehrer's D2-D6. We will assume a background deductive logic whose consequence relation is represented by the straight turnstile 'f-'. 6 We will assume that this background logic is a compact, consistent extension of classical tmth-functionallogic and that an expressively complete set of boolean connectives is available in the language: C 1. Where p is a sentence and X a set of sentences, X X f- or p is justified on the basis of X.

~

p iff either

C2. p is justified on the basis of X if and only if p coheres with X. C3. p coheres with X if and only if all objections to p are answered or

neutralized on X.

CHARLES B. CROSS C4.

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is an objection to P on X if and only if it is more reasonable to accept p on the assumption of --'0 than on the assumption of 0 on the basis of X. 0

C5. p answers 0 on X if and only if 0 is an objection to p on X, and it is more reasonable to accept p than to accept 0 on X. C6. n neutralizes 0 as an objection to p on X if and only if 0 is an objection to p on X; and 0 & n is not an objection to p on X; and it is as reasonable to accept 0 & n as to accept 0 alone on X. Since the account of cumulative inference to be given below is developed with classical logic as a background, Cl is formulated in such a way that if X is logically inconsistent then X f-v p for all p. Coherence figures in whether X f-v p only if X is logically consistent. It would be interesting to see a paraconsistent version of the logic developed here, but that is a project for another occasion.

3.1.

Basic Postulates aud Related Results

Given C 1-C6, the key to the logic of 'f-v' will of course be the logic of the comparative reasonableness relation. Lehrer (2000:144) states that he takes comparative reasonableness as undefined, but he identifies both probability (Lehrer 2000:144) and epistemic utility (Lehrer 2000:146) as factors in the determination of the degree of reasonableness of a claim. Lehrer (2000: 146) even provides an expected utility equation for calculating degrees of reasonableness. Our approach to comparative reasonableness will be entirely nonquantitative. 7 We will treat comparative reasonableness relative to a set X of sentences as a binary relation >- x relating one pair (p, q) of sentences to another such pair. A locution of the form 'It is more reasonable to accept p on the assumption of q than to accept r on the assumption of s on the basis of X' will thus be abbreviated '(p, q) >- x (r, s)'. With comparative reasonableness understood qualitatively, the following all seem plausible as principles of comparative reasonableness:

Noutriviality If (p, q)

>- x (r, s) then X

}L .

Asymmetry If(p,q) >-x (r,s) then (r,s) 'Ix (p,q). Irreftexivity If X

}L,

then (p, q)

'I x (p, q). 'I X (p3, q3)

then

Equivalence If p -Jf- p' and q -Jf- q' and r -Jf- r' and s -Jf- s', then (p, q) (r,s) iff (p',q') >-x (r',s').

>- X

Negative Transitivity If (PI, ql)

(PI, ql)

'I x (P3, q3).

'I X (p2, q2)

and (p2, q2)

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Superiority If X f- p and X .J.L, then (p, T) onX.

»- x (q, T) for all objections q to p

Enlargement for Objections If X ~ p, then every objection to q on X is an objection to q on X U {p}. Enlargement for Answering If X ~ p and 0 is an objection to q on both X and Xu {p}, then q answers 0 on.X only if q answers 0 on Xu {p}. Enlargement for Neutralizing If X ~ p and 0 is an objection to q on both X and X U {p}, then for all n, n neutralizes 0 as an objection to q on X only if n neutralizes 0 as an objection to q on X U {p}. Reduction for Objections If X ~ p, then every objection to q on X U {p} is an objection to q on X. Reduction for Answering If X ~ p and 0 is an objection to q on both X and X U {p}, then q answers 0 on X U {p} only if q answers 0 on X. Reduction for Neutralizing If X ~ p and 0 is an objection to q on both X and X U {p}, then for all n, n neutralizes 0 as an objection to q on X U {p} only if n neutralizes 0 as an objection to q on X.

Nontriviality conveys the idea that distinctions of comparative reasonableness cannot be made if X is inconsistent. 8 Asymmetry and Irreflexivity are supported intuitively by the more in more reasonable than. To expose the significance of Negative Transitivity, let us next make the following definition:

(p,q)

~x

(r,s)

ifandonlyif

(p,q)

'l-x (r,s) and (r,s) 'l-x (p,q).

The following result follows immediately by Nontriviality, Irreflexivity, Asymmetry, and Negative Transitivity: Theorem 1 For any fixed X, of the form (p, q).

~x

is an equivalence relation on the set ofpairs

That is, ~ x is reflexive, symmetric, and transitive for any fixed X. The fact that ~ x is an equivalence relation makes it acceptable to interpret' (p, q) ~ x (r, s)' as meaning it is as reasonable to accept p given q as to accept r given s on the basis of X. Where q and s are both logical truths, '(p, q) ~ x (r, s)' means p is as reasonable as r on X, and it is this notion of equal reasonableness that we appeal to in C6. The fact that ~x is an equivalence relation also yields the following useful substitution principle.

CHARLES B. CROSS Theorem 2

If (PI , qI)

(rI' 8r) iff(p2, q2)

'::::.X (p2, q2) and (rIl 81) '::::.x (r2' 82), then (PI, qr)

>- X (r2' 82).

117

>- x

Proof: Assume that (PI, qI) '::::.x (p2, q2) and (rI, 8r) '::::.x (r2, 82). Now for reductio suppose that (PI, qr) >- X (rI' 8r), but (p2, q2) >I- X (r2' 82). By hypothesis, (PI, qI) >I- X (p2, q2) and (p2, q2) >I- X (r2' 82) and (r2' 82) >I- X (rI' 81). By two applications of Negative Transitivity, (PI, qr) >I- X (rI, 81), which is contrary to hypothesis. So by reductio if (PI, qI) >- X (rr, 81) then (p2, q2) >- X (r2' 82)' An exactly similar argument shows that if (p2, q2) >- X (r2, 82) then (PI, qI) >- X (rI' 8r). (QED)

Equivalence has this direct consequence: Theorem 3

If X f-v P and P -1r q,

then X

f-v

q.

Proof: Suppose that X f-v P and P -1r q. If X r then X f-v q follows immediately, so suppose X j,L. Then every objection to P on X is either answered or neutralized. Let 0 be an obj ection to q on X. Then (q, -'0) >- X (q, 0), but since P -1r q it follows by Equivalence that (p, -'0) >- X (p, 0). Hence 0 is an objection to p, so 0 is either answered or neutralized as an objection to P on X. Suppose that 0 is answered as an objection to P on X. Then (p, T) >- x (0, T), but since P -1r q, it follows by Equivalence that (q, T) >- x (0, T). Hence 0 is answered as an objection to q on X. Alternatively, suppose that n neutralizes 0 as an objection to P onX. Then (p, -,(o&n)) >l-x (p, o&n) and (o&n, T) '::::.x (0, T). Since P -1r q, it follows by Equivalence that (q, -, (0 & n)) >I- x (q, 0 & n), so n neutralizes 0 as an objection to q. So 0 is either answered or neutralized as an objection to q on X. Generalizing on 0, it follows that X f-v q. (QED)

Superiority expresses the idea that the logical consequences of a consistent set X answer all of their respective objections. The role of Superiority in the logic of coherence is to ensure that the principle of Supraclassicality holds for f-v: Theorem 4

If X r

P then X

f-v p.

Proof: Suppose that X r p. If X r, then X f-v P by C1 and we are done. Alternatively, suppose X j,L. Then, by Superiority, P answers all of its objections on X. Hence X f-v p. (QED)

Theorem 4 has Reflexivity as a direct consequence: Theorem 5

IfP E

X then X

f-v p.

As far as coherence is concerned, Enlargement and Reduction for Objections together entail that if P coheres with X and X is logically consistent, then P has

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the same objections on X as on X U {p}. If P coheres with X and X is logically consistent, then Enlargement and Reduction for Answering entail that the same pairs of claims stand in the answering relation on X as on X U {p}, whereas Enlargement and Reduction for Neutralizing entail that the same objections to a given claim are neutralized by the same neutralizers on X as on X U {p}. Thus, expanding a given set of claims by adding something that coheres with the given set neither increases nor decreases the set of claims that cohere. As far as ~ is concerned, the principles of Enlargement and Reduction for Objections, Answering, and Neutralizing serve to ensure that Cautious Monotony and Cut hold: Theorem 6

If X

~ p and X ~ q, then X U {p} ~ q.

Proof: Suppose that X ~ pandX ~ q. If XU{p} 1-, thenXU{p} ~ q by CI, so suppose Xu {p} }L , and let a be an objection to q on X U {p}. By Reduction for Objections, a is an objection to q on X. Since X ~ q, a is answered or neutralized as an objection to q on X. By Enlargement for Answering and Enlargement for Neutralizing, a is answered or neutralized as an objection to q on X U {p}. Generalizing on 0, X U {p} ~ q. (QED) Theorem 7

If X

U {p} ~ q and X ~ p, then X ~ q.

Proof: Suppose that Xu {p} ~ q and X ~ p. If X 1-, then X ~ q by CI, so suppose X }L, and let a be an objection to q on X. By Enlargement for Objections, a is an objection to q on Xu {p}. Since Xu {p} ~ q, a is answered or neutralized as an objection to q on X U {p}. By Reduction for Answering and Reduction for Neutralizing, 0 is answered or neutralized as an objection to q on X. Generalizing on 0, X ~ q. (QED)

Of course, the six Enlargement and Reduction principles can be assumed to be lemmas whose basis lies in further assumptions about comparative reasonableness. What further assumptions are needed? The following invariance principle for comparative reasonableness turns out to suffice: Invariance Under Inductive Expansion (IUIE) If X }L and X ~ p, then for all q, r, s, and t, (q, r) >- X (s, t) iff (q, r) >- xu{p} (s, t). Theorem 8 IUIE implies Enlargement for Objections. Proof: Assume IUIE and X ~ p, and let a be an objection to q on X. Then (q,--,o) >-x (q,o). ByIUIE, (q,--,o) >-xu{p} (q,o),henceoisanobjectiontoq on Xu {p}. (QED)

CHARLES B. CROSS

119

Theorem 9 IUIE implies Reduction for Objections. Proof: Similar to the proof of Theorem 8. (QED) Theorem 10 IUIE implies Enlargementfor Answering. Proof: Assume that X f-v p and 0 is an objection to q on both X and X U {p} and q answers 0 onX. Then (q, T) >- x (0, T). By IUIE, (q, T) >- xU{p} (0, T). Hence q answers 0 on Xu {p}. (QED) Theorem 11 IUIE implies Reduction for Answering. Proof: Similar to the proof of Theorem 10. (QED) Theorem 12 IUIE implies Enlargement for Neutralizing. Proof: Assume that X f-v p and 0 is an objection to q on both X and X U {p}. Let n neutralize 0 as an objection to q on X. Then (q, -'(0 & n)) 'I- x (q, 0 & n) and (0 & n, T) ~x (0, T). By IUIE, (q, -'(0 & n)) 'I- xu{p} (q,o & n) and (o&n, T) ~xu{p} (0, T). HencenneutralizesoasanobjectiontoqonXU{p}. (QED) Theorem 13 IUIE implies Reduction for Neutralizing. Proof: Similar to the proof of Theorem 12. (QED) 3.2.

Some Postulates aud Results for Negation

Since the language in which our logic is formulated includes an expressively complete set of truth-functional connectives, every sentence (including every logical truth) has a boolean negation. The following postulates seem reasonable as principles relating comparative reasonableness to sentences and their negations:

Inconsistency If X J.L and {p, q} f--- and {p} J.L and {q} J.L, then (p, -,q)

(p, q). Top/Bottom If X J.L and {p} J.L, then (T, p) Bottom/Top If X J.L, then el,.1)

>- x (.1, T).

Exclusive Objection for.1 If (.1, -,p)

>- x (.1,p), then f--- p.

Exclusive Equivalence If X J.L and (.1, T) Top Level If X J.L and (T, T)

~x

>- x Cl, p).

~x

(p, T), then {p}

(p, T), then f--- p.

f---.

>- x

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RELATIONAL COHERENCE AND CUMULATIVE REASONING

The upshot of Inconsistency is that a pair of individually consistent but jointly inconsistent statements are always objections to one another. Top/Bottom entails that a logical truth is always more reasonable, given a consistent assumption p, than any contradiction given that same assumption. Assuming Equivalence, Bottom/Top entails that every logical truth is an objection to every contradiction, and Exclusive Objection for ..l entails that every objection to a contradiction is a logical truth. Exclusive Equivalence entails that anything which is exactly as reasonable as a contradiction is itself a contradiction. Top Level entails that anything which is exactly as reasonable as a logical truth is itself a logical truth. An important consequence of this collection of principles is the thesis that f-v has the property of Consistency Preservation: Theorem 14

If X ¥

then there is no p such that X

f-v p and X f-v

-'p.

Proof: Suppose that X ¥. For reductio, suppose that there is a p such that X f-v p and X f-v -'p. Case 1: Suppose that I- p. Then -,p -II- ..l, so by Theorem 3, X f-v ..l. Since X ¥, it follows that every objection to ..l is either answered or neutralized on X. By Bottom/Top and Equivalence, (..l, -, T) 'r x (..l, T), so T is an objection to ..l on X. Since ¥ -, T, we have by Top/Bottom that (T, T) 'r x (..l, T), so by Asymmetry, (..l, T) >f x (T, T). By Exclusive Objection for ..l, every objection to ..l on X is logically equivalent to T, so by Equivalence, (..l, T) >f x (0, T) for every objection 0 to ..l on X. Hence ..l does not answer any of its objections on X. Let n neutralize 0 as an objection to ..l on X. Then 0 is an objection to ..l on X and 0 & n is not an objection to ..l on X and (0 & n, T) r:::=.x (0, T). Exclusive Objection for ..l implies that 0 -II- T, so by Equivalence we have that T & n is not an objection to ..l on X, i.e. (..l, -,(T & n)) >f x (..l, T & n), and T & n is as reasonable as T on X, i.e. (T & n, T) r:::=.x (T, T). But T & n -II- n, so by Equivalence, (i) (..l, -,n) >f x (..l, n) and (ii) (n, T) r:::=.x (T, T). By Top Level, (ii) implies n -II- T, from which it follows by (i) and Equivalence that (..l,..l) >f x (..l, T), which contradicts Top/Bottom. So a contradiction follows from the hypothesis that I- p. Case 2: Suppose that I- -'p. This hypothesis leads to a contradiction by an argument similar to Case 1. Case 3: Suppose that ¥ p and ¥ -'p. By Inconsistency, (p, -,-,p) 'r x (p, -,p) and (-,p, -,p) 'r X (-,p, p). Hence -,p is an objection to p on X and p is an objection to -'p on X. Since X f-v p and X f-v -,p and X ¥, -,p is either answered or neutralized as an objection to p on X, and p is either answered or neutralized as an objection to -'p on X. Asymmetry implies that p and -,p

CHARLES B. CROSS

121

cannot answer each other. Hence either -,p is neutralized as an objection to p on X, or p is neutralized as an objection to -,p on X. But neither of these alternatives is possible. Let n be any sentence, and suppose for reductio that n neutralizes -,p as an objection to p on X. Then -,p & n is not an objection toponX,i.e. (p,-,(-,p&n)) >l-x (p,-,p&n),and(-,p&n,T) ~x (-,p,T). Since {-,p} J.L, it follows by Exclusive Equivalence that { -,p & n} J.L. Since, in addition, (p, -, (-,p & n)) >I- x (p, -,p & n) and {p} J.L and {p, -,p & n} f-, Inconsistency is contradicted. By reductio, -,p is not neutralized as an objection to p on X. Exchanging p and -'p, an exactly similar argument shows that pis not neutralized as an objection to -,p on X. The hypothesis of Case 3, that J.L p and J.L -'p, therefore leads to a contradiction. (QED) Consistency Preservation is a significant property because any consistencypreserving inference relation that allows inferences which go beyond the deductive consequences of a set must be nonmonotonic: 9 Theorem 15 Suppose that ~ is a relation on pairs consisting of sets of sentences and sentences, and suppose that ~ satisfies Reflexivity, Consistency Preservation, and Superclassicality:

Consistency Preservation: If X ¥ then there is no p such that X ~ p and X ~ -'p. Superciassicality: For some p, X

~

p but X J.L p.

Then ~ is nonmonotonic, i.e. there are X, Y, and p such that X C Y and X ~ p but Y J76 p. Proof: Assume Reflexivity, Consistency Preservation and Superclassicality. By Superclassicality, find a p such that X ~ p but X J.L p. Since X J.L p, it follows that X U { -,p } J.L . By Reflexivity, X U { -,p} ~ -'p, so by Consistency Preservation, Xu {-,p} J76 p. It therefore suffices to let Y = Xu {-,p}. (QED) 3.3.

Postulates and Results for Disjunction

Since Boolean disjunction is present in the object language, it is reasonable to ask how disjunction interacts with our coherence-based inference relation' Kraus, Lehmann, and Magidor (1990:190) and Makinson (1989:14) consider analogs of the following "introduction on the left" rule for disjunction:

r-' .

Or If X U {p}

r- r and X U {q} r- r, then X U {p V q} r- r.

The Or postulate follows if we make the following reasonable assumptions about objections, answering, and neutralizing.

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RELATIONAL COHERENCE AND CUMULATIVE REASONING

Left Replacement If X U {p} XU{q} r--r.

r-- r

and X U {p} f- q and X U {q} f- p, then

Objection for Disjunctions If Xu {p} J.L and Xu {q} J.L and X U {p} r-- r and Xu { q} r-- r, then every objection to r on Xu {p V q} is an objection to r on both X U {p} and X U {q}. Answering and Neutralizing for Disjunctions If Xu {p} J.L and Xu {q} Y and X U {p} r-- r and X U {q} r-- r, and if 0 is an objection to r on X U {p V q} which is answered or neutralized as an objection to r on X U {p} and as an objection to r on X U {q}, then 0 is answered or neutralized as an objection to r on Xu {p V q}. Theorem 16 If Left Replacement, Objection for Disjunctions, and Answering and Neutralizingfor Disjunctions hold, then the Or postulate holds. Proof: Assume Left Replacement, Objection for Disjunctions, and Answering and Neutralizing for Disjunctions, and suppose that XU{p} r-- rand XU{ q} r-r. If Xu {p V q} f-, then Xu {p V q} r-- r by C 1, so suppose that X U {p V q} J.L . If X U {p} f- , then X U {p V q} f- q, in which case, since X U { q} f- p V q and Xu { q} r-- r, it follows by Left Replacement that X U {p V q} r-- r. Similarly, if X U {q} f-, then X U {p V q} r-- r, so suppose that X U {p} J.L and X U {q } J.L . Let 0 be an objection to r on X U {p V q}. By Objection for Disjunctions, o is an objection to r on X U {p} and on X U {q}. Hence 0 is answered or neutralized as an objection to r on X U {p} and 0 is answered or neutralized as an objection to r on Xu {q}. By Answering and Neutralizing for Disjunction, o is answered or neutralized as an objection to r on Xu {p V q}. Generalizing on 0, X U {p V q} r-- r. (QED)

Left Replacement follows from the following plausible principle on comparative reasonableness, where Cn(X) = {p: X f- p}: Invariance Under Reformulation If Cn(X) = Cn(Y), then for all p, q, r, ands, (p,q) >--x (r,s) iff(p,q) >--y (r,s). Theorem 17 Invariance under Reformulation implies that if X U {p} Xu {p} f- q and Xu {q} f- p, then X U {q} r-- r.

r-- rand

Proof: Assume Invariance under Reformulation and suppose that X U {p} r-- r and X U {p} f- q and X U { q} f- p. If X U { q} f-, then X U { q} r-- r by C 1, so suppose that X U {q} J.L. Since X U {p} f- q and X U {q} f- p, it follows that Cn(X U {p}) = Cn(X U {q}). Let 0 be an objection to r on Xu {q}. Then (r, -'0) >-- xu{ q} (r, 0). By Invariance under Reformulation, (r, -'0) >-- xu{p}

CHARLES B. CROSS

123

(r, 0). Hence 0 is an objection to r on X U {p}. Since X U {p} f"v r, it follows that 0 is answered or neutralized on X U {p}. Case 1: Assume thatr answers 0 on XU{p}. Then (r, T) >- xU{p} (0, T). By Invariance under Reformulation, (r, T) >- xU{q} (0, T). Hence r answers 0 onX U {q}. Case 2: Assume that there is an n such that n neutralizes 0 as an objection to r on Xu {p}. Then (0 & n, -,r) tXU{p} (0 & n, r) and (0 & n, T) ~xu{p} (0, T). By Invariance under Reformulation, (0 & n, -,r) t xU{q} (0 & n, r) and (0 & n, T) ~XU{q} (0, T). Since 0 is also an objection to r on Xu {q}, n neutralizes 0 as an objection to r on Xu {q}. By Cases 1 and 2, it follows that 0 is answered or neutralized as an objection to r on Xu {q}. Hence Xu {q} f"v r, as required. (QED)

The following principle is sufficient to derive Objection for Disjunctions:

Distribution for Disjunction If X U {p} j,L and X U {q} j,L, then for all r, s, t, and u, (r,s) >-xu{pvq} (t,u) only if (r,s) >-xu{p} (t,u) and (r,s) >-xu{q}

(t,u).

Theorem 18 Distribution for Disjunction implies Objection for Disjunctions. Proof: Assume Distribution for Disjunction, and suppose that X U {p} j,L and X U {q} j,L and X U {p} f"v r and X U {q} f"v r. Let 0 be an objection to r on Xu {p V q}. Then (r, -'0) >- xu{pVq} (r,o). By Distribution for Disjunction, (r, -'0) >- xU{p} (r,o) and (r, -'0) >- xU{q} (r,o). Hence 0 is an objection to r on both X U {p} and X U {q}. (QED) The question of how to secure Answering and Neutralizing for Disjunctions via a reasonable principle of comparative reasonability remains an open problem.

3.4.

Deductive Closure for Inductive Consequences

When, as in this paper, cumulative reasoning is formalized in the context of a deductive background logic, the question arises whether the inductive consequences of a set form a deductively closed set. The following proof-theoretic postulates jointly suffice as a definition of deductive closure for 'f"v':

Special Supraclassicality If r- p then X Right Modus Ponens If X

f"v p.

f"v p:J q and X f"v p, then X f"v q.

Special Supraclassicality follows from Supraclassicality and so is a consequence of Superiority, but Special Supraclassicality also follows immediately from Top/ Bottom, Equivalence, and the following two principles:

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RELATIONAL COHERENCE AND CUMULATIVE REASONING

Top/Top (T, T) )- x (T, -.1). Exclusive Objectiou for T If X J.L and (T, ...,p) )- x (T, p), then {p} f-. Theorem 19 .if Top/Bottom, Top/Top, Equivalence, and Exclusive Objection for T hold, then if f- p then X f-v p. Proof: Assume Top/Bottom, Top/Top, Equivalence, and Exclusive Objection for T, and let f- p. If X f-, then X f-v p by Cl, so assume that X J.L. Since (T, T) )- x (T, -.1) by Top/Top, it follows by Equivalence and Exclusive Objection for T that q is an objection to T on X iff q -1f- -.1. Since {T} J.L , it follows by Top/Bottom that (T, T) )- x (-.1, T). Since -.1 -1f- q for every objection q to T on X, it follows by Equivalence that T answers all of its objections on X. Hence X f-v T. Since f- p, p -1f- T; hence by Theorem 3 we have that X f-v p. (QED)

Right Modus Ponens follows if we assume the following three principles: Objection for Conditionals If X J.L and X same objections on X.

f-v p,

Answering for Conditionals If X J.L and X then q answers a on X.

f-v

then q and p ::J q have the

p and p :J q answers a on X,

Neutralizing for Conditionals If X J.L and X f-v p and n neutralizes 0 as an objection to p ::J q on X, then n neutralizes a as an objection to q on X. Theorem 20 .if Objection, Answering, and Neutralizing for Conditionals hold, then if X f-v P ::J q and X f-v p, then X f-v q. Proof: Assume Objection, Answering, and Neutralizing for Conditionals, and suppose that X f-v p::J q and X f-v p. If X f-, then X f-v q by Cl, so suppose that X J.L . Let r be an objection to q on X. Then by Objection for Conditionals, r is an objection to p ::J q on X. Since X f-v p ::J q, r is answered or neutralized as an objection to p ::J q on X. If p ::J q answers r on X, then, by Answering for Conditionals, q answers r on X. If there is an n such that n neutralizes r as an objection to p ::J q on X, then, by Neutralizing for Conditionals, n neutralizes r as an objection to q on X. So r is answered or neutralized as an objection to q on X. Generalizing on r, X f-v q. (QED)

Objection, Answering, and Neutralizing for Conditionals in turn follow from the following simple requirement on comparative reasonableness: Conditional Invariance If X J.L and X (p::Jq,r).

f-v

p, then for all q and r, (q, r)

~x

CHARLES B. CROSS

125

Theorem 21 Conditional Invariance implies ObjectionJor Conditionals. Proof: Assume that X r and X [-v p. Let 0 be an objection to q on X. Then (q, -'0) ;.- x (q,o). By Conditional Invariance, (q, -'0) ~x (p:=J q, -'0) and (q, 0) ~x (p:=J q, 0). By Theorem 2, (p :=J q, -'0) ;.- x (p:=J q, 0). Hence 0 is an objection to p :=J q on X. So every objection to q on X is an objection to p:=J q on X. A similar argument shows that every objection to p :=J q on X is an objection to q on X. (QED) Theorem 22 Conditional Invariance implies AnsweringJor Conditionals. Proof: Assume that X r and X [-v p and p :=J q answers T on X. Then T is an objection to p :=J q on X and (p :=J q, T) ;.- X (T, T). By Theorem 21, T is an objection to q on X. By Conditional Invariance, (q, T) ~x (p:=J q, T), and, since ~x is an equivalence relation, (T, T) ~x (T, T). By Theorem 2, it follows that (q, T) ;.- X (T, T). Hence q answers T on X. (QED) Theorem 23 Conditional Invariance implies NeutralizingJor Conditionals. Proof: Assume that X r and X [-v p and n neutralizes T as an objection to p :=J q on X. Then T is an obj ection to p :=J q on X, and T & n is not an obj ection to p:=J q on X, and (T & n, T) ~x (T, T). By Theorem 21, T is an objection to q on X and T & n is not an objection to q on X. Hence n neutralizes T as an objection to q on X. (QED)

4.

CONCLUSION

We have seen that it is possible to interpret a slightly simplified version of Lehrer's (2000) theory of relational coherence as a species of inductive reasoning, indeed as a species of cumulative reasoning, and we have seen that the cumulativity of this species of inductive reasoning can be derived from certain very plausible assumptions about comparative reasonableness. The additional properties of Consistency Preservation and deductive closure for inductive consequences can also be derived from plausible principles of comparative reasonableness. It remains to be seen whether Or and Answering and Neutralizing for Disjunctions can be derived from plausible principles of comparative reasonableness. As an exercise in logic, the hypothesis that relational coherence is a species of inductive reasoning appears to be a success. But does this way of looking at relational coherence have any epistemological significance? Clearly it does. The criterion of coherence with one's evaluation system is intended by Lehrer, in the first instance, as a means of evaluating the personal justification

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RELATIONAL COHERENCE AND CUMULATIVE REASONING

status of claims that a subject accepts against a larger background consisting of acceptance, reasoning, and preference systems. But any criterion of epistemic justification has to be more than this. Regardless which theory of knowledge is correct, it is surely true that any truth-seeking, error-averse subject who seeks to expand what he or she accepts should add only beliefs which he or she would be justified in holding if he or she held them. And the process of adding beliefs in this fashion is nothing ifnot inductive reasoning. Accordingly, if Lehrer's coherence theory of knowledge is correct, then any truth-seeking, error-averse subject wishing to reason inductively should do so by expanding his or her acceptance system to include claims which would cohere with his or her evaluation system. Nothing, therefore, could be more natural in the context of Lehrer's theory of knowledge than an account of inductive reasoning in terms of relational coherence.

ENDNOTES

* I am pleased and honored to participate in celebrating the career of so brilliant a philosopher as Keith Lehrer. Lehrer's status as a leading figure in the field is richly deserved, and, without a doubt, his work will continue to stand the test of time. 1 Cumulativity was defined by Gabbay (1985), but see also Kraus et al. 1990, Makinson 1989, and Makinson 1994. 2 But see Lehrer 2000:144-146 for a discussion of relative reasonableness, probability, and expected value. 3 In this and later sections, the variables p, q, r, and s range over statements in some given language, and the variables X and Y with and without subscripts range over sets of statements. The expression 'X f- p' means that p can be inferred from X in the inference system defined by'f-'. 4 See Makinson 1994 for a survey. 5 In parallel with Lehrer's definitions, "it is more reasonable to accept p than to accept r on the basis of X" will be assumed to mean "it is more reasonable to accept p on the assumption T than to accept r on the assumption T on the basis of X", where T is some fixed logical truth. 1. is defined as -, T. 6 'p -jf- q' will mean that {p} f- q and {q} f- p. Where X is a set of sentences, 'X f- ' will mean that X f- p and X f- -,p for some p. 7 In Lehrer's theory, comparative reasonableness is conditional as well as comparative ("it is more reasonable to accept p on the assumption q than to accept r on the assumption s"). For a well worked-out example of a nonquantitative theory of unconditional comparative reasonableness, see Chisholm and Keirn 1972. 8 It might be argued that distinctions of comparative reasonableness can be made in such cases. If this is right, then our adoption of Nontriviality should be considered a simplifying assumption that reflects a decision not to address comparative reasonableness for inconsistent X. 9 See Cross 1990 for an application of a version of this result to the question of the tenability of the Ramsey test for conditionals.

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REFERENCES Chisholm, R. and R. G. Keirn. 1972. "A system ofepistemic logic." Ratio 14:99-115. Cross, C. 1990. "Belief revision, nonmonotonic reasoning, and the Ramsey test." In Knowledge Representation and Defeasible Reasoning, edited by H. Kyburg, R. Loui, and G. Carlson, 223-244. Dordrecht: Kluwer. Gabbay, D. 1985. "Theoretical foundations for non-monotonic reasoning in expert systems." In Logics and Models of Concurrent Systems, edited by K. R. Apt, 439-457. Berlin: Springer-Verlag. Kraus, S., D. Lehmann, and M. Magidor. 1990. "Nonmonotonic reasoning, preferential models, and cumulative logics." Artificial Intelligence 44:167-207. Lehrer, K. 1974. Knowledge. Oxford: Oxford University Press. ~~-. 1986. "The coherence theory of knowledge." Philosophical Topics 14:5-25. ~~-. 1988. "Metaknowledge: Undefeated justification." Synthese 74:329-347. ~~-. 2000. Theory ofKnowledge. 2nd ed. Boulder: Westview Press. Makinson, D. 1989. "General theory of cumulative inference." In Lecture Notes in Artificial Intelligence 346: Nonmonotonic Reasoning, edited by M. Reinfrank, 1. de Kleer, M. L. Ginsberg, and E. Sandewall, 1-18. Berlin: Springer-Verlag. Makinson, D. 1994. "General patterns in nonmonotonic reasoning." In Handbook of Logic in Artificial Intelligence and Logic Programming, Volume 3: Nonmonotonic Reasoning and Uncertain Reasoning, edited by D. M. Gabbay, C. 1. Hogger, and 1. A. Robinson, 35-110. Oxford: Oxford University Press. Shoham, Y. 1988. Reasoning about Change. Cambridge: MIT Press.

Chapter 8 LEHRER MEETS RANKING THEORY Wolfgang Spohn University of Konstanz

Meets what? Ranking theory is, as far as I know, the only existing theory suited for underpinning Keith Lehrer's account of knowledge and justification. If this is true, it's high time to bring both together. This is what I shall do in this paper.! However, the result of defining Lehrer's primitive notions in terms of ranking theory will be disappointing: justified acceptance will, depending on the interpretation, either have an unintelligible structure or reduce to mere acceptance, and in the latter interpretation knowledge will reduce to true belief. Of course, this result will require a discussion of who should be disappointed. So, the plan of the paper is simple: In section 1 I shall briefly state what is required for underpinning Lehrer's account and why most of the familiar theories fail to do so. In section 2 I shall briefly motivate and introduce ranking theory. Basing Lehrer's account on it will be entirely straightforward. Section 3 proves the above-mentioned results. Section 4, finally, discusses the possible conclusions.

1.

THE BASIC NOTIONS OF LEHRER'S ACCOUNT OF JUSTIFICATION AND KNOWLEDGE

I shall base my considerations on Lehrer (2000), the most recent presentation of his theory. It indeed adds simplifications and clarifications to the first edition. For instance, the basic notions on which his theory of knowledge and justification builds stand out more clearly. They are summarized in his definition of an evaluation system in Lehrer (2000, p. 170, D 1)2 which consists of three components: (a) an acceptance system, i.e., a set of accepted statements or propositions, (b) a preference system, i.e., a four-place relation among all 129 E.!. Olsson (ed.), The Epistemology of Keith Lehrer, 129-142. © 2003 Kluwer Academic Publishers.

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LEHRER MEETS RANKING THEORY

statements or propositions saying for all A, B, e, D whether A is more reasonable to accept given or on the assumption that ethan B given or on the assumption that D (I symbolize it here as Ale >- BID),3 and (c) a reasoning system, i.e., a set of inferences each consisting of premises and a conclusion. The idea behind (c) is that what a person accepts, and justifiedly accepts, depends also on the inferences she carries out. Here I understand Lehrer as referring to deductive inferences or rather to the inferences taken by the person to be deductively valid and sound. 4 The idea behind (b), by contrast, is to take care of inductive reasoning in the widest sense which is always a matter of weighing reasons and objections on the basis of some such preference system. We shall look in detail at Lehrer's specific proposal for this weighing ofreasons. The first step I would like to take in my present discussion is to fix the reasoning system once for all. The reason is that otherwise my comparative business could not even start. Of course, we shall have to discuss in the final section whether this is already the first misrepresentation of Lehrer that will entail all the other ones. How do I fix that system? Since Lehrer emphasizes again and again that he is interested in acceptance only insofar as it is governed by the aim of truth, I propose to extend this attitude to the objects of belief or acceptance and to conceive of them only insofar they can be true or false, i.e., as truth conditions or propositions. Thereby, I ignore all questions of syntactic structure, of logical equivalence, and of logical entailment, and assume that the rationality constraint of consistency and deductive closure of the acceptance system is trivially satisfied. This entails in particular the assumption that the reasoning system is maximal and has no independent role to play. I am well aware that I am taking this step very swiftly. My excuse is that I am convinced that a lengthy treatment of the issue would not reveal a viable constructive alternative. Having taken this step the task of underpinning reduces to accounting for the acceptance and the preference system. Concerning the latter, the first idea is, of course, to appeal to a probability measure P and to define that Ale >- BID iff P(AIc) > P(BID). However, the relation between probability and acceptance is problematic, as is highlighted by the famous lottery paradox. I am not rejecting all attempts to solve this paradox out of hand, but the mere fact that they are debated heatedly and that all ofthem are contested shows that probability theory is, presently, not a good foundation for Lehrer's theory. Moreover, as I shall point out below, there is a particular feature in Lehrer's notion of neutralizing an objection which prevents any probabilistic interpretation. Olsson (1998a) discusses further difficulties of a purely probabilistic construal of justified acceptance. For similar reasons Lehrer, too, has given up on finding purely probabilistic foundations, which he still hoped to build in Lehrer (1971, 1974). There he suggests, moreover, that the foundations may be construed as some kind of epistemic decision theory. The hint is still found in Lehrer (2000,

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pp.145ff.) and also used for a solution of the lottery paradox. However, I am doubtful because epistemic decision theory has remained a promise that has never been redeemed in a satisfying way in the last 35 years. The basic difficulty, I believe, is this: Probability theory may claim, in a way, to offer a complete epistemology. If so, it is hard to complement it or to merge it with other epistemological ideas like acceptance, epistemic decisions, or whatever, and radical probabilism as Jeffrey (1992) has defended it seems unavoidable. Hence, we should put probability theory aside and rather look at theories dealing directly with acceptance or belief. A large variety of such theories-such as default logic, AGM belief revision theory, Pollock's and other accounts of defeasible and non-monotonic reasoning, etc.-has been developed in the past 25 years. Maybe they provide an account of Lehrer's preference system as well. Alas, they don't. At least, I claim this with confidence with respect to AGM belief revision theory. There it is shown that the behavior of belief revisions is equivalent to the behavior of so-called entrenchment relations. 5 These could indeed fill the role of Lehrer's unconditional preference relation. Maybe entrenchment relations can be generalized so as to capture the special case A IC >- BIC of Lehrer's preference relation which refers twice to the same condition. However, Lehrer requires the full conditional relation, which cannot be accounted for in AGM belief revision theory. I suspect that essentially the same is true of all accounts of defeasible reasoning implicitly or explicitly appealing to some kind of epistemic ordering. There is only one theory that is about belief or acceptance and provides a sufficiently powerful preference system: ranking theory. That's why I said it is the only existing theory suited for underpinning Lehrer's account. What does it look like?

2.

RANKING THEORY

The basics are quickly told. Originally, ranking theory was developed 6 in order to overcome essential restrictions of AGM belief revision theory. As it turns out, AGM theory generally accounts only for one step of belief revision and thereafter returns to a static picture. But, of course, a full dynamics has to account for several or iterated belief changes. The problem has been around since Harper (1976), and there have been quite a number of attempts to solve it within the confines of AGM theorizing.? However, I find these proposals inferior to the one provided by ranking theory. Iterated belief revision is not our concern here. However, there exists a close connection between iterated belief change and full conditional epistemic preference. 8 It is for this reason that ranking theory, though addressed to the former, can also provide for the latter. So let's take a look.

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Let's start with an exhaustive set Wofpossibilities (possible worlds, firstorder valuations, or whatever). Subsets of Ware propositions (let's not worry about their algebraic structure), W itself is the logically true and 0 the logically false proposition. As explained above, I take such propositions as objects of epistemic attitudes. Ranks, then, are grades of disbelief (where I find it natural to take nonnegative integers as grades, but other numbers would do so as well). These grades obey some fundamental laws summarized in Definition 1: K is a ranking function iff K is a function from the power set of W into Nu{ rf)} such that K(W) = 0, K(A) = rf) iff A = 0, and K(AuB) = min{K(A), K(B)}. K(A) is called the rank of A. The rank ofB given A is defined as K(BIA) = K(AnB) - K(A). Hence, K(A) > 0 says that A is disbelieved (to some degree), and K(A) > 0 says that A is believed. 9 K(A) = 0 only expresses that A is not disbelieved and leaves open the possibility that A is not disbelieved as well. Since there is no point here in distinguishing between belief and acceptance, we thus have Definition 2: A is accepted by K iffK(A) > O. {A IA is accepted by K} is the acceptance system ofK. What are the fundamental laws according to Definition I? K(W) = 0 says that the logically true proposition is not disbelieved. The condition that K(A) = rf) iff A = 0 says that it is most strongly believed, i.e., that the logically false proposition is more strongly disbelieved than any other. More substantial is the law ofdisjunction that K(AuB) = min {K(A), K(B)}. Clearly, the disjunction AuB cannot be more firmly disbelieved than either of its disjuncts. Nor can it be less firmly disbelieved than both disjuncts, since this would entail the absurdity that given AuB both, A and B, are disbelieved, though AuB is not. An immediate consequence is the law ofnegation that either K(A) = 0 or K(A) = 0 (or both). A and A cannot be both disbelieved. Perhaps the most important law is the law of conjunction that K(AnB) = K(A) + K(BIA) which follows trivially from the definition of conditional ranks. It says that in order to arrive at the degree of disbelief in AnB one has to sum up the degree of disbelief in A and the additional degree of disbelief in B given A. This, I believe, agrees with intuition. There is a surprisingly well working translation from probabilistic into ranking terms which almost automatically generates a large number of ranking theorems from probability theorems. This applies also to the account of belief change. The basic rule for probabilistic belief change is simple conditionalization according to which one moves to the probabilities conditional on the information received. This is generalized by Jeffrey's conditionalization lO which is

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unrestrictedly performable and thus defines a full dynamics within the realm of strictly positive probability measures. In the corresponding way, such conditionalization with respect to ranks offers a full dynamics of belief or acceptance. 11 This informal hint at belief revision may suffice. However, we should formally introduce belief contraction because Lehrer makes explicit use of it in what he calls the ultrasystem. Belief contraction is the operation of giving up some belief without adding new ones. It is extensively discussed in AGM belief revision theory because it is interchangeable with belief revision.!2 Within ranking theory it is easily defined as well (and turns out then to have all the properties described in AGM theory!3): Definition 3: The contraction K - A of K by A is defined by K - A = K, if K(A) = O. If not, it is defined by (K - A) (B) = K(B) for B <;:;;; A and (K - A) (B) = K(B) - K(A) for B <;:;;; A; for other B the rank may be inferred from these conditions by applying the law of disjunction.

Hence, if A is not believed, anyway, the contraction by A does not have any effect at all. And if A is believed, i.e., A is disbelieved, then again (K - A) (A) = 0, i.e., A is no longer disbelieved after the contraction. However, the ranks conditional on A and on A are unaffected by the contraction. So much for ranking theory as such. Let us now apply it to Lehrer's epistemology.

3.

LEHRER'S ACCOUNT OF JUSTIFICATION AND KNOWLEDGE IN RANKING TERMS

Conditional ranks do not only allow us to account for (iterated) belief revision and contraction. They also offer what we are directly aiming at, namely an explanation of Lehrer's preference system, i.e., of his primitive four-place relation >- : Definition 4: A is more reasonable to accept given C than B given D relative to K, i.e., AIC >- BID, iff K(AIC) > K( BID). Moreover, A is more reasonable to accept than B, A >- B, iff AIW >- BIW, i.e., K(A) > K( B ). Similar notions are defined correspondingly.

Hence, a ranking function K comprises all components of what Lehrer calls an evaluation system: an acceptance system (see Definition 2), a preference system (see Definition 4), and a reasoning system (as trivialized by me above).

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LEHRER MEETS RANKING THEORY

One may be tempted to say that Lehrer's account is wedded to ranking theory. The wedding is unhappy, however. On the basis of Definition 4, Lehrer's account ofjustification is translated in a straightforward way, and the fatal results are inescapable:

Definition 5 (= 04, p. 170): B is an objection to A iff AI B >- AlB. Is being an objection a relation among accepted propositions or among propositions in general? The latter according to Definition 5, though Lehrer may intend the former. However, there is no issue here, since we shall have to stipulate that justified acceptance entails acceptance and shall thus consider only objections to accepted propositions. Otherwise, we would get nonsensical results.

Definition 6 (= 05, p. 170): The objection B to A is answered iff B is an objection to A, i.e., AI B >- AlB, and A >- B. Definition 7 (= 06, p. 170): C neutralizes the objection B to A iff

B is an objection to A, i.e., AI B >- AlB, BnC is not an objection to

-

-

i.e., BnC

c:: B.

A, i.e, AI B u C ::5 AIBnC, and BnC is at least as acceptable as B,

Indeed, it is this last condition that prevents a probabilistic interpretation of Lehrer's preference system because it would be empty in this interpretation; no objection could then be neutralized. In ranking terms, however, this consequence need not be feared. Thus, we arrive at

Definition 8 (= 03 and 07, pp. 170 f.): A isjustifiedly accepted, or the acceptance of A is personally justified, relative to K in the strong sense iff A is accepted and each objection to A is answered or neutralized by some C. This is the literal translation of Lehrer's definition. My qualification "in the strong sense" indicates, however, that we shall have to consider a weaker sense as well. Unfortunately, this chain of definitions yields strange results. What is justifiedly accepted according to Definition 8 is an unintelligible selection from the accepted propositions. In order to define this selection let Em = U{D I K(D) ;:> m}; hence, Em is the logically weakest proposition having at least rank m. Then we have:

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Theorem 1: A is justifiedly accepted relative to K in the strong sense iff, given K(A) = n > 0, for all m ?: n with Em - Em+1 =f- 0 A n Em - En1m+! =f- 0 holds true (or, equivalently, iff for all m ?: n with K(Em) = m there is aD (;;; A with m :<:: K(D) :<:: n+m). Proof Suppose there is an m for which this condition does not hold. Clearly, m = n cannot be the exception. Hence, m > n. Now take any B such that K(S) = m. Since A n Em - En+m+1 = 0, K(An B ) ?: n+m+ 1. In any case K(AnB) = n. So we have K(AI B ) ?: n+ 1 > K(A IB), i.e., B is an unanswered objection to A. How

could a C neutralize this objection? It should satisfy K( B u m and thus K( C)

?:

m. Hence, still K(An( B u C))

?:

C) =

n+m+ 1 and

K(AnBnC) = n, and so K(AI B u C) > K(AIBn C). Thus, there can be no neutralizer, and A is not justifiedly accepted relative to K.

Suppose conversely that the condition holds true for all m unfolds into three cases:

?:

n. This

First, it may be that K(A) = 00, i.e., A = W. Since for all m ~ 00 Em = 0, the condition is satisfied. However, in this case there can be no objection to A, and so A is justifiedly accepted. Second, it may be that K(A) = n < 00 and indeed A = En' Suppose B is an objection to A. This requires at least K(AI B ) > 0. Suppose further that B is not answered. This requires K(A) :<:: K( B). But since A = En' this entails B (;;; A and thus K(AI B) = 0. Contradiction. Hence, there is no unanswered objection to A, and A is justifiedly accepted. Third, it may be that K(A) = n < 00 and A c En' Then there is a B with K(B) = m and B (;;; (En - A) u E n+m+!, and exactly those B are unanswered objections to A, since exactly those B satisfy both, m ?: n, i.e., K( B) ?: K(A), and K(An B) ~ n+m+ 1, which is tantamount to K(AI B ) > K(AIB), since K(AIB) = n. But we have supposed that A n Em - En+m+l =f- 0. This secures that B can be neutralized. Take any C such that A n Hence m

:<::

K(

E n+m+l (;;; C (;;; Em. = m = K( B ), and K(A

Em -

C) < n+m+ 1. SO, K( B u C)

n( B u C)) < n+m+ 1, and hence K(AI B u

C)

:<::

n

=

K(AIBnC).

136

LEHRER MEETS RANKING THEORY Therefore, any unanswered objection to A can be neutralized in this case, and, again, A is justifiedly accepted.

Now, we can see why we had to restrict justified acceptance to accepted propositions in Definition 8. If we had omitted this proviso, the proof of Theorem 1 would have to consider the case where K(A) = O. However, for n = oevery bit of the proof would go through in the same way. This would allow for many justifiedly accepted propositions not previously accepted. Indeed, even 0, the logically false proposition, would turn out as justifiedly accepted! Simply because there can be no objections to 0 according to Definition 5; 0 is maximally disbelieved under all conditions. So, this had to be avoided. Still, Theorem 1 is awkward. I have tried to express the necessary and sufficient condition for justified acceptance as perspicuously as possible (but I cannot circumvent the mathematical facts). However, this condition just makes no intuitive sense. If Lehrer's definitions force us to distinguish between justifiedly and unjustifiedly accepted propositions in this way, then there is something wrong with the definitions. Indeed, there may be cause for suspicion. For instance, objections may be restricted to inductive objections, where B is an inductive objection to A iff K(AIB) < K(AI Ii) < 00. Or I was wondering whether Lehrer really meant Definition 7 as stated. Perhaps, the idea of neutralization is better expressed by the condition that given the neutralizer C the objection B to A is no longer an objection to A ( i.e., AI Ii nC ::5 AIBnC). However, as far as I have checked, this leads to nowhere. Theorem 1 thereby changes considerably, but does not improve. No, a better cure is revealed by noticing that Theorem 1 implies that justified acceptance is not even deductively closed: if A is justifiedly accepted and logically implies B, B still need not be justifiedly accepted. This seems to be a flaw in Definition 8 as it stands. But then, of course, we have to correct Definition 8. Thinking about what one is personally justified to accept means also working through one's reasoning system. Given my fixation of the reasoning system, this leads us to the following weaker and more adequate sense of justified acceptance:

Definition 9: A is justifiedly accepted relative to K in the weak sense iff A is logically implied by propositions justifiedly accepted in the strong sense. 14 What is justifiedly accepted in this sense? This is answered by

Theorem 2: A is justifiedly accepted relative to K in the weak sense iff A is accepted by K.

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Proof The proof of Theorem 1 shows that £1 is justifiedly accepted. If A is accepted by K, i.e., K(A) > 0, then A <:;;;; E 1, i.e., £\ <:;;;; A. Thus A is logically implied by somethingjustifiedly accepted.

In a sense, this looks much nicer, but it empties Lehrer's theory of justification. So, it looks undesirable as well. Theorem 2 would not change under the modifications of Lehrer's defin itions mentioned above. These results also affect Lehrer's theory of knowledge. In order to see how we must first turn to undefeated justification and the ultrasystem. A person's ultrasystem is generated from her evaluation system by deleting from the latter all acceptances of, preferences for, and reasonings from falsehoods. This is immediately explicable in ranking terms. Let w* E W be the true or actual possibility in W, and let us consider any evaluation system, i.e., ranking function K. If everything accepted in K is true, then no falsehoods intrude into the justifications with respect to K, anyway. In this case, K is its own ultrasystem. That's the rare case, though. Usually, some false proposition will be believed in K. This entails K( {w*}) > 0. Hence, the logically weakest falsehood accepted by K is (w*). Now, if we contract K by (w*) , not only this falsehood, but also all other, stronger falsehoods must go (since the contracted acceptance system is again deductively closed). Hence, in the resulting ranking function K* exactly the true among the propositions accepted by K are accepted. Moreover, if A is true and B is false, then K*(A) = :<:; K*(B), and hence in the preference system provided by K* no false proposition is ever preferred to a true one, as required by Lehrer in D8, p. 171. Finally, we do not worry about the reasoning system of1.c*, for the familiar reason. All in all, the explication is remarkably smooth, and we may conclude with

°

Definition 10 (= D8, p. 171): The ultrafunction K* ofK is K- (w*) ,

the contraction ofK by (w*). This covers also the case where no falsehood is accepted in K, i.e., where K* =K. On this basis, the rest of Lehrer's definitions is immediately translated: Definition 11 (= D9, p. 171): The justification for accepting A in K is undefeated (or irrefutable) iff A is justifiedly accepted in K*. Definition 12 (= DK, pp. 169f.): A is known in K iff (i) A is accepted in K, (ii) A is true, i.e., w* E A, (iii) A is justifiedly

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LEHRER MEETS RANKING THEORY accepted in undefeated.

K,

and (iv) the justification for accepting A in

K

is

Lehrer's claim that knowledge reduces to undefeatedly justified acceptance, i.e., to condition (iv) is now easily confirmed. But stronger results obtain. If knowledge is based on justified acceptance in the strong sense, just those propositions are known which satisfY the condition of Theorem 1 relative to K*. Unpalatable knowledge! If knowledge is based on justified acceptance in the more adequate weak sense, we get Theorem 3: A is known in K iff A is true and A is accepted in

K.

Proof Theorem 2 reduces condition (iii) to (i). But, Theorem 2 applies also to K*. Hence, (iv) reduces to acceptance in K*, and hence to (i) and (ii). Thus, again, the sophisticated considerations relating to the ultrasystem seem empty, and knowledge reduces to true belief, a conclusion Lehrer definitely wants to avoid.

4.

WHAT TO CONCLUDE?

It is not clear what to think of these results. I find that the structure of what I called justified acceptance in the strong sense is too weird to be worth discussing. Hence, I proceed on the assumption that it is the weak sense that is relevant. I have already indicated why I believe to agree with Lehrer on this point. But Theorems 2 and 3 look troublesome as well, though it is not clear where to locate the trouble. There are several ways, and more than one good way, to respond. (1) One may point to various flaws in my translation. For instance, I have carelessly interchanged belief and acceptance, whereas Lehrer (pp. 12f.) emphasizes their difference. Likewise, I have defined an acceptance system as a set of accepted propositions, whereas for Lehrer it is a set of propositions ofthe form "I accept that A". But these kinds of flaws are insignificant. Also, I have neglected Lehrer's own foundations in terms of trustworthiness (pp.138ff.), but taking them into account would have no effect on the present considerations. However, my fixation of Lehrer's reasoning system by rightaway assuming deductive closure is doubtlessly a major deviation from Lehrer. But, again, I don't think it does any harm. The acceptance system to start with could as well consist in an arbitrary, not deductively closed set of accepted statements, as long as it is consistent. Working out what is justified on the basis of such an

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acceptance system means working out the preference system, which is a more permanent disposition of the epistemic subject extending to all statements. And it means, as we have observed above, working out the reasoning system, i.e., accepting the logical consequences of what one has justifiedly accepted. Hence, we are back at deductive closure, at least as far as justified acceptance is concerned. Theorem 2 then says that the deductive closure of an acceptance system is justifiedly accepted relative to this system, and this is equally troublesome. No, Theorems I and 2 are generated by the characteristics of the preference system as specified by a ranking function. The trouble lies there and not in my light way of dealing with deductive relations. (2) This suggests another conclusion. If one proceeds from preference systems generated by ranking functions and arrives at such undesired results, then the two theories do not fit together, and one has to look for other preference systems. After all, nobody claims that ranking theory delivers the only legitimate kind of preference systems. So, the conclusion would be that ranking theory may have useful applications, but Lehrer's account ofjustification does not belong to them. (3) However, I tend to the reverse conclusion. The more offers for an underpinning of Lehrer's account are rejected, the stronger the obligation to come up with some sound theoretical foundation. As for my part, I doubt that there is any better offer than the one made here. In any case, as long as the foundation is missing, there is not really any theory of justification and knowledge. Perhaps this quest for a theoretical underpinning is too strong, though. Concerning the acceptance system the picture rather seems to be that it collects all the variegated items of information and inference, with the aim of truth, but without critical standards. Any arbitrary set of statements may be formed in this way. Then, it seems, there can be no theory about acceptance systems, and asking for one is asking too much. This attitude, however, does not carry over to the preference system. We need not entertain the illusion that it is uniquely determined by rationality alone. Carnap was under this illusion with inductive logic, but soon woke up. The preference system and hence the standards ofjustification may well be subjective to some extent. However, this is not to say that anything goes. This would mean anarchy and throwing away the idea of rationality altogether. Some rationality standards should be set up and defended. This is just what ranking theory attempts to do, though perhaps in a debatable way. In any case, one cannot simply be silent on the structure of preference systems. Hence, if one thinks that the theorems above are undesirable, then, I think, Lehrer's account of justification is really in trouble. (4) Perhaps, though, one need not think that the theorems are undesirable. When comparing ranking theory with Pollock's defeasible reasoning in Spohn

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LEHRER MEETS RANKING THEORY

(2002) I concluded, among other things, that ranking functions are best compared with what Pollock calls ideal warrant, which is, so to speak, the end product of his defeasible reasoning machinery. IS Though Pollock's theory is quite different from Lehrer's, this suggests that acceptance according to ranking functions is already justified acceptance. This suggestion is supported by the fact that ranking acceptance cannot yield any arbitrary acceptance system, but is deductively closed, due to a correctly and maximally executed reasoning system. In this perspective, then, Theorem 2 would not at all be surprising, it should be expected. Accordingly, ranking theory and Lehrer's account ofjustification may indeed be seen as mutually supporting each other, since Theorem 2 shows that they reach the same result via entirely different considerations. Too much harmony? Yes, I think so. First, the talk of ideal warrant is Pollock's, and it was helpful in the above-mentioned comparison. But there is nothing in ranking theory by itself forcing this comparison. Ranking theory is, as I prefer to say more neutrally, about rational belief and its dynamics. So, Theorem 2 rather shows either that ranking theory is about ideal warrant, despite my disclaimer, or that ideal warrant reduces to rational belief. This would be my preferred conclusion, but it reopens, it seems, a difference to Lehrer. Secondly, even if Theorem 2 lends support to Lehrer's account of justification, it does so in an unfriendly way, because it renders it vacuous at the same time. The sophisticated considerations about answering and neutralizing objections do not do any real work. This holds also when one starts, as Lehrer does, from an arbitrary, unorderly acceptance system, because it is simply its deductive closure that is justified relative to it. 16 This vacuity is certainly against Lehrer's intentions. Thirdly, there remains a problem with Theorem 3. If, as stated above, ranking functions represent rational belief and nothing stronger, then the reduction of knowledge to true belief as represented by ranking functions appears doubtful, even though it has been defended by von Kutschera (1982, sect. 1.3), and Sartwell (1991, 1992). In any case, it is unacceptable to Lehrer. Atthis point, hence, harmony ceases at the latest. So, as I said, it is not really clear what to conclude, though (3) would be my preferred conclusion. The case shows once more how difficult it often is to square different epistemological approaches. However, there is, I think, a general lesson to learn. Justification is a central notion in epistemology, and hence it is rightly scrutinized in many discussions, from many perspectives, and with many examples and arguments. In all that literature, though, I find very little rigorous theory. However, the amenability to rigorous theorizing provides an important test. This test is usually not even sought. I? But it is useful as a critical and as a constructive authority. At least I hope to have shown this here with respect to the paradigm of Lehrer's epistemology.

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141

ENDNOTES I I am indebted to Gordian Haas for various valuable remarks and for discovering bad faults in a first draft which required major corrections and to Erik Olsson for further helpful suggestions. 2 In the sequel, mere page numbers are always meant to refer to Lehrer (2000). 3 In D 1, p. 170, Lehrer mentions only the unconditional preference relation, but it is clear that he requires the conditional one. 4 On p. 127, when introducing the reasoning system, Lehrer refers only to "cogent" reasoning, and generally the notion of validity makes clear sense only relative to deductive inference. 5 See Al chourr6n et al. (1985), which is considered as the foundation of AGM belief revision theory, or Gardenfors (1988, ch. 4). 6 In Spohn (1983, sect, 5.3) and (1988). 7 Cf., e.g., Nayak (1994). 8 The connection is not obvious and perhaps not cogent. In order to really understand it we would have to go much more deeply into issues of belief revision than we can and need to do here. 9 A is the complement of A with respect to W. The thinking in negations will continue, though I am fully aware that it is cumbersome. 10 Cf. Jeffrey (1965, ch. 11). II Cf. Spohn (1988, sect. 5). 12 Cf. Gardenfors (1988, ch. 3). 13 Cf. Spohn (1988, p. 133, footnote 20). 14 Lehrer (1971, p.221) took recourse to the same move when observing that the rule of induction he proposed is not deductively closed. 15 Cf. Pollock (1995, sect. 3.10). 16 If the initial acceptance system should be inconsistent, the theoretical situation changes drastically. Then paraconsistent logic may help, or the theory of consolidation (cf. Hansson 1994 and Olsson 1998b), or whatever. But there is no evidence in Lehrer's writings that this is his problem. 17 For instance, it springs to one's eyes that at least three ofthe five conditions Bonjour (1985, pp. 95-99) offers for coherence are theoretically hardly explicable.

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REFERENCES Alchourr6n, C.E., P. Gardenfors, D. Makinson (1985), "On the Logic of Theory Change: Partial Meet Functions for Contraction and Revision", Journal of Symbolic Logic 30, 510-530. BonJour, L. (1985), The Structure of Empirical Knowledge, Cambridge, Mass.: Harvard University Press. Gardenfors, P. (1988), Knowledge in Flux, Cambridge, Mass.: MIT Press. Hansson, S.O. (1994), "Taking Belief Bases Seriously", in: D. Prawitz, D. Westerstahl (eds.), Logic and Philosophy of Science in Uppsala, Dordrecht, Kluwer, pp. 13-28. Harper, W.L. (1976), "Rational Belief Change, Popper Functions, and Counterfactuals", in: W.L. Harper, c.A. Hooker (eds.), Foundations ofProbability Theory, Statistical Inference, and Statistical Theories of Science, vol. I, Dordrecht: Reidel, pp. 73-115. Jeffrey, R.C. (1965), The Logic of Decision, Chicago: The University of Chicago Press, 2nd ed. 1983. Jeffrey, R.C. (1992), Probability and the Art of Judgment, Cambridge: Cambridge University Press. Lehrer, K. (1971), "Induction and Conceptual Change", Synthese 23, 206-225. Lehrer, K. (1974), "Truth, Evidence, and Inference", American Philosophical Quarterly 11,79-92. Lehrer, K. (2000), Theory of Knowledge, Boulder, Colorado: Westview Press, 2nd edition. Nayak, A.c. (1994), "Iterated Belief Change Based on Epistemic Entrenchment", Erkenntnis 41, 353-390. Olsson, E. (1998a), "Competing for Acceptance: Lehrer's Rule and the Paradoxes of Justification", Theoria 64, 34-54. Olsson, E. (1998b), "Making Beliefs Coherent", Journal ofLogic, Language, and information 7, 143-163. Pollock, J.L. (1995), Cognitive Carpentry, Cambridge, Mass.: MIT Press. Sartwell, C. (1991), "Knowledge is Merely True Belief" American Philosophical Quarterly 28, 157-165. Sartwell, C. (1992), "Why Knowledge is Merely True Belief", Journal ofPhilosophy 89, 167-180. Spohn, W. (1983), Eine Theorie der Kausalitat, unpublished Habilitationsschrift, Munich. Spohn, W. (1988), "Ordinal Conditional Functions. A Dynamic Theory of Epistemic States", in: W.L. Harper, B. Skyrms (eds.), Causation in Decision, BeliefChange, and Statistics, vol. II, Dordrecht: Kluwer, pp. 105-134. Spohn, W. (2002) "A Brief Comparison of Pollock's Defeasible Reasoning and Ranking Functions", Synthese 31, 39-56. von Kutschera, F. (1982), Grundfragen der Erkenntnistheorie, Berlin: de Gruyter.

Chapter 9 TWO DOGMAS OF PROBABILISM Carl G. Wagner* The University of Tennessee

1.

INTRODUCTION

Lehrer's epistemology, as articulated, for example, in Rational Consensus in Science and Society (Lehrer and Wagner 1981), has always emphasized that rational decision making must take account of the total available evidence. Yet dogmatic restrictions on the representation of uncertain judgment, or on the way in which such judgment may be revised, undermine the goal of faithfully representing the evidence. In this paper we discuss two such restrictions, dogmatic Bayesianism and the dogma ofprecision, and outline some ways in which probabilism has begun to be liberated from their grip. Dogmatic Bayesianism, which asserts that the only acceptable method of revising a probability distribution is by conditionalizing on an event E that one has come to regard as certain, has already been substantially weakened by the discovery of principled ways of updating probabilities when conditionalization is simply inapplicable. Since descriptions of these alternative revision methods are accessible and clear, we shall simply mention 1) revising one's probability distribution by means of a weighted average of that distribution along with those of other informed individuals (Lehrer and Wagner 1981); 2) probability kinematics (Jeffrey 1965, 1983, 1988), a generalization of conditionalization in which new evidence alters the probabilities of a disjoint family of events; and 3) reparation (Jeffrey 1991, 1995; Wagner 1997, 1999), a revision method 143

E.l. Olsson (ed.), The Epistemology of Keith Lehrer, 143-152. © 2003 Kluwer Academic Publishers.

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TWO DOGMAS OF PROBABILISM that raises the probability of hypothesis H when it is discovered that H implies previously known evidence E. 1

Probabilism, which allows the representation of degrees of belief by subjective probabilities taking any values in the interval [0, 1], itself offers a profound expansion of the classical dogmatic epistemological categories "accept," "reject," and "suspend judgment." Yet the expressive resources ofprobabilism need to be further enlarged. Recall that on the standard account (Ramsey 1990) subjective probability is a measure of one's degree of confidence in the truth of a proposition or the occurrence of an event, as reflected in one's willingness to take either side of certain bets. It is supposed that one is always capable of articulating the precise odds governing such bets. That this dogma of precision, as Walley (1991) has called it, is both unrealistic and unnecessary, is gaining acceptance among students of the foundations of probability. In what follows we outline the elementary parts of the theory of upper and lower probabilities, with the aim of giving these ideas wider currency among epistemologists.

2.

SUBJECTIVE PROBABILITY AND THE DOGMA OF PRECISION

For the sake of simplicity it is assumed in what follows that your frame of discernment n regarding possible states of the world is finite. 2 It is also supposed that there is an infinitely divisible unit of utility. Suppose that you are able to assign to each event A c n a real number p(A) such that 1° You are willing to pay anything less thanp(A) units of utility in exchange for receiving one such unit if A occurs, and nothing if A fails to occur; and 2° In exchange for receiving anything more than p(A) units of utility, you are willing to obligate yourself to pay one such unit if A occurs, and nothing if A fails to occur. The set function p is your subjective probability on events in n, with p( A) being your threshold price/or A.3 Standard Dutch book arguments (see, e.g., Earman 1992, pp. 38-40) show that in order to avoid a sure loss, p must be coherent, i.e., satisfy the usual axioms for a probability measure,

p(A) ~ 0,

for all A

en,

and p(n) = 1, p(A U B) = p(A) + p(B), for all A, Ben such that A n B =

(2.1) (2.2) 0.

(2.3)

CARL G. WAGNER

145

In section 4 we show as a simple corollary of a much more general result that coherence is also sufficient to avoid a sure loss. The demands placed on probability assessors by the dogma of precision are stringent, and unrealistic. How, for example, is one to assess the probability of getting a white ball in a random selection from an urn containing red and white balls in unknown proportion?4 An additional such example, the case of incompletely specified contingency tables, is described in the next section. As we shall see, an elegant analysis of this case, due to Strassen (1964), leads naturally to a simple, intuitively appealing general account of upper and lower probabilities.

3.

STRASSENIAN UPPER AND LOWER PROBABILITIES

Imagine a collection of objects, consisting of spheres, cylinders, cubes, and cones, each of which is colored red, white, or blue. Suppose that 50 % of the objects are red, 30 % are white, and 20 % are blue. There are no red cubes or red cones, no white cylinders or white cubes, and no blue spheres. An object is chosen at random from this collection. What is the probability that it is 1. a sphere, 2. a sphere or cylinder? This problem involves the incomplete contingency table sphere whil£ cod blue

cylinder

cube

cone

I

and furnishes another example in which information is insufficient to assess precise probabilities. On the other hand it is fairly easy to see, e.g., that no more than 80 % of the objects can be spheres, and that at least 50 % of the objects are spheres or cylinders. Strassen (1964) furnished the following elegant analysis of the general problem of this type: Let 0 and 8 be frames of discernment regarding the state of the world, let p be a probability on events in 0, and suppose that for each w E 0 the set T(w), comprising those outcomes E 8 compatible with the outcome w, is nonempty. For all A c 8, let

e

A* := {w EO: T(w) A* := {w EO: T(w)

c A}, n A =I 0},

and

(3.1) (3.2)

and let

p(A) := p(A*), a(A) := p(A*).

and

(3.3) (3.4)

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TWO DOGMAS OF PROBABILISM

The set functions (3 and a are, respectively, the Strassenian lower and upper probabilities 5 on events in 8 induced by p and the compatibility relation T. The reasons for this terminology will soon be made clear, but let us first note some basic properties of these set functions.

Theorem 3.1. The set functions (3 and a defined by (3.3) and (3.4) have the following properties: (i) 0 ~ (3(A) ~ a(A) ~ l,for all A

c

8.

(ii) (3(0) = a(0) = 0 and (3(8) = a(8) = 1.

if Al

(iii) (3 and a are monotone, i.e., a(At) ~ a(A2)'

(iv) (3 and a are conjugates, i.e., (3(A)

C A 2, then (3(AI) ~ (3(A 2) and

+ a(A) =

lfor all A C 8.

(v) For every positive integer r, (3 is r-monotone and a is r-alternating, i.e. (3(AI U ... U AT) ~ L

(3(Ai) i

- L(3(Ai n Aj) i<j

+ ... + (-lr- I (3(A I n .. · nAT)

(3.5)

and a(AI n ... n AT) ~ L

a(Ai) i

- L a(A U Aj) i<j

+ ... + (-lr-Ia(AI u··· U AT),

(3.6)

from which it follows that (vi) (3 is superadditive and a is subadditive, i.e., if Al nA 2 = 0, then (3(AI U A 2) ~ (3(At) + (3(A2) and a(AI U A 2) ~ a(At) + a(A2)'

Proof The proofs of (i)-(iii) are straightforward. The proof of (iv) follows from the fact that A* and (A)* are set-theoretic complements. To prove (3.5) note that (AI U ... U A T)* => (At)* u ... U (AT)* and that for every I C {I, ... ,r}

Then apply monotonicity of p and the principle of inclusion and exclusion for p. The inequality (3.6) follows from (3.5) and (iv). Assertion (vi) follows from the 0 case r = 2 of(3.5) and (3.6).

CARL G. WAGNER

147

Theorem 3.2. The following are equivalent: (i)

If p( w) > 0,

then w is compatible with exactly one outcome

e E 8.

(ii) {3 is a probability measure.

(iii)

0:

(iv) {3

is a probability measure.

=

0:.

o

Proof Straightforward.

The above theorem simply confirms what one would expect, namely, that when T is in effect a 8-valued random variable, then 0: and {3 coincide with the usual probability measure induced on events in 8 by p and T. We now demonstrate the appropriateness of calling 0: and (3 upper and lower probabilities. In what follows, fA denotes the indicator of the event A, i.e., fA(e) = 1 ife E A and fA(e) = 0 ife E A, and we routinely omit the phrase "units of utility." The betting commitments described in 10 and 2 0 of section 2 above will be tersely characterized, as a willingness to "buy fA for p(A) - c, for all c > 0," and "sell fA for p(A) + c, for all c > 0." Suppose that p is your subjective probability on events in D, with T, 0:, and (3 as above. Except in the case described in Theorem 3.2, you have inadequate information to ground assessment of a subjective probability on events in 8. There are, however, identifiable constraints on any such probability.

Theorem 3.3. Any coherent probability q that might be a candidate for representing your threshold prices for events in 8 must satisfy

(3(A) for

~

q(A)

~

for all A

o:(A),

c 0),

(3.7)

if (3.7) is violated, you will suffer a sure loss.

Proof Suppose that q(A) < (3(A) for some A c 8, with (3(A)-q(A) = c > O. You'll sell fA for q(A) + c/4 and buy fA. for p(A*) - c/4 = (3(A) - c/4. Suppose that w is the true D-state and that is the true 8-state. If w E A*, then E A, and so your net gain is (q(A) +c/ 4-1) + (1- (3(A) +c/ 4) = -15/2 < O. If w 1: A*, mayor may not be an element of A. If E A, your net gain is (q(A) + c /4- 1) + (0 - (3(A) + c / 4) = -1 - c /2 < 0, and if 1: A, your net gain is (q(A) + c/4 - 0) + (0 - (3(A) + c/4) = -c/2 < O. Supposethatq(A) > o:(A). Thenq(A) = 1-q(A) < l-o:(A) = (3(A), by Theorem 3.1 (iv), which leads, as above, to a sure loss. 0

e

e

e

e

e

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TWO DOGMAS OF PROBABILISM

As noted above, you are perfectly justified in the above situation in refusing to announce threshold prices for events in 8. But there are some additional bets that you ought to be willing to make:

Theorem 3.4. If f3 and a are defined by (3.3) and (3.4) you ought to be willing, for each A c 8, and for all c > 0, to 1° buy lAfor f3(A) - c, and

2° sell lAfor a(A)

+ c.

Proof The argument here is not that you will otherwise suffer a sure loss (no one can make a Dutch book against someone unwilling to bet), but, rather, that 1° and 2° are at least as good as bets you are willing to make. In the case of 10, you'll buy lA. for p(A*) - c = f3(A) - c, so you ought to be willing to buy lA for that price, since if the true D- and 8-states are, respectively, wand e, and w E A*, then e E A, so lA pays off for you in every case that lA* does, and possibly other cases as well. In the case of 2°, you'll sell lA* for p(A*) + c = a(A) + c, so you ought to be willing to sell I A for that price. With wand e as above, if w t/: A *, then T(w) n A = 0, i.e., T(w) c A. Since e E T(w), e t/: A. So in every case in which you avoid paying off on IA* (and perhaps in other cases as well) you will avoid paying off on IA. 0

4.

UPPER AND LOWER SUBJECTIVE PROBABILITIES

Theorem 3.4 leads naturally to the following generalization of classical subjective probability: Suppose that for each event A c D you are able to assign real numbers A(A) and v(A) such that, for all c > 0, you are willing to 1° buy lA for A(A) - c, and 2° sell IA for v(A)

+ c.

The set functions A and v are then, respectively, your lower and upper subjective probabilities on events in D. Whereas in section 2 above your threshold prices as bettor and bookie were required to be identical, here they may be distinct, with obvious gains in realism and expressive possibility. The following theorem gives necessary and sufficient conditions for avoiding a sure loss in the above situation:

Theorem 4.1. Given the betting commitments 1° and 2° above, you will avoid a sure loss if and only if there exists a coherent probability q on events in D such that (4.1) for all A c D. A(A) ~ q(A) ~ v(A),

CARL G. WAGNER

149

o

Proof See Walley 1981, p. 15.

It follows immediately from Theorem 4.1 that coherence of subjective probabilities, as defined in section 2 above, is not only necessary, but also sufficient to avoid a sure loss (cf. Kemeny 1955 and Lehman 1955). Note that (4.1) is a rather weak condition, which, for example, does not even imply monotonicity of A and u. Buehler (1976) has argued for much more stringent restrictions. Indeed, he claims inter alia that the lower probability A must be additive! Buehler's argument is based on the following theorem.

Theorem 4.2. Suppose that A(A) ~ q(A)for all A c n, where q is a coherent probability, and that A is self-conjugate, i.e., A(A) + A(A) = 1 for all A c D. Then A = q.

Proof Suppose that A(A) < q(A) for some A. Then, by self-conjugacy of A, A(A) = 1- A(A) > 1-q(A) = q(A), contradicting thefact that A is dominated byq. 0 It follows from Theorems 4.1 and 4.2 that if A avoids a sure loss, and is self-conjugate, then A is in fact a coherent probability. Buehler's argument that A must be self-conjugate goes as follows: Clearly, A(A) + A(A) ~ 1; otherwise you will suffer a sure loss. Suppose that A(A) + A(A) < l. Let a and b be such that A(A) < a, A(A) < b, and a + b < l. Then you'll reject buying fA for a and fA for b, even though by accepting both bets you would be guaranteed of the net gain 1 - a - b > O. So you will miss out on a sure gain. Apart from the fact that missing a sure gain is considerably less serious than suffering a sure loss, this argument is further weakened by its dependence on your being offered fA and fA one at a time, with no knowledge that both will be offered. If you were offered these bets simultaneously, you would recognize immediately that you were being offered a certain payoff of 1, and would clearly agree to pay any price less than 1 in exchange. Here is a simple way in which lower and upper probabilities satisfying (4.1) arise: Let P be a nonempty family of coherent probabilities on events in D and let

Ap(A)

:= iuf {p(A)},

vp(A)

:=

pEP

sup{p(A)}.

and

(4.2) (4.3)

pEP

Then Ap and Up satisfy (4.1) as well as the conjugacy relation Ap(A)+up(A) = l. The set functions Ap and Up are, respectively, the lower and upper envelopes

oip·

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TWO DOGMAS OF PROBABILISM

Examples of naturally occurring families 'P (called probasitions in Jeffrey 2001) include such things as 1. the family of all additive representations of some comparative probability relation (Roberts 1976) and 2. the family of all probabilities with respect to which a fixed random variable has a fixed expected value. The Strassenian lower and upper probabilities (3 and a are also envelopes, with 'P = the set of all marginalizations to e of all probabilities Q on 0 x e that are compatible with p and T in the sense that the marginalization of Q to 0 is p and Q(w, e) = 0 if e tt T(w) (Wagner 1992).

5.

CONCLUSION

Dogmatic restrictions on the representation of uncertain judgment, or on the way in which such judgment is revised, undermine the goal offaithfully representing the evidence regarding the state of the world. While Bayesian dogmatism has begun to yield to other principled methods of probability revision, the dogma of precision is still dominant. One source of resistance to working with non-additive upper and lower probabilities is the fear that such measures must necessarily be mathematically intractable. This greatly exaggerates the true state of affairs. While space does not permit a detailed account, we mention that there is a useful theory of upper and lower expectation (see Dempster 1967 and Walley 1981, 1991), as well as a generalization of probability kinematics in which new evidence places bounds on possible revisions of prior in the form of Strassenian upper and lower probabilities (Wagner 1992). Finally, to conclude this paper on the same note on which it began, we remark that there is a theory of consensus for upper and lower probabilities (Wagner 1989) which is remarkably similar to that in Lehrer and Wagner 1981.

ENDNOTES * Research supported by the National Science Foundation (SES-9984005) Reparation thus provides a solution to the old evidence problem, first posed by Glymour (1980). The term "frame of discernment" is due to Shafer (1976). The elements of 0 are mutually exclusive and exhaustive, i.e., precisely one element of 0, though typically unknown, represents the true state of the world. Multiple frames of discernment may, however, be brought to bear on a single problem, as, for example, when we classify the possible outcomes of selecting an object at random from a set of colored shapes by frames delineating I) the possible colors and 2) the possible shapes. Mathematicians typically refer to 0 as a "sample space." 3 It is implicit here that you are unwilling to pay more than p( A) in 10 and unwilling to take less than p(A) in 2°. In the usual treatment, you must be willing to pay p(A) in 10 and to take p(A) in 2°. We do not require this. A virtue of our treatment is that one can assign proper subsets of 0 (i.e., contingent events) probability one without being in the position of having no prospect of 1

2

CARL G. WAGNER

151

positive gain, and the possibility of a loss (cf. Eannan 1992, p. 41). Our treatment also allows for a natural segue to the account of upper and lower probabilities in section 4. 4 Devotees of the principle of insufficient reason would adopt the unifonn distribution here, thus employing the same distribution in the case of complete ignorance that they would given reliable infonnation that exactly half the balls in the urn are white. 5 In 1967 Dempster, unaware of Strassen's 1964 paper, published a similar analysis. Shafer (1976) offered a sui generis account of set functions having the monotonicity properties of the lower probability (3, regarding such set functions, which he called beliejjimctions, as directly assessable measures of degrees of belief.

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REFERENCES Buehler, R. 1976. "Coherent Preferences." Annals ojStatistics 4: 1051--1064. Dempster, A. 1967. "Upper and Lower Probabilities Induced by a Multivalucd Mapping." Annals of Mathematical Statistics 38:325-339. Earman,1. 1992. Bayes or Bust? Cambridge: MIT Press. Glymour, C. 1980. Theory and Evidence. Princeton: Princeton University Press. Jeffrey, R. 1965. The Logic of Decision. New York: McGraw-Hill; 1983, 2nd ed., Chicago: University of Chicago Press. ----. 1988. "Conditioning, Kinematics, and Exchangeability." In B. Skyrms and W. Harper (eds.), Causation, Chance, and Credence, vol. I, Dordrecht: Kluwer,221-255. - - - . 1991. "Postscript 1991: New Explanation Revisited." In Jeffrey 1992, 103-107. - - - . 1992. Probability and the Art ofJudgment. Cambridge: Cambridge University Press. '---. 1995. "Probability Reparation: The Problem of New Explanation." Philosophical Studies 77:97-102. 2001. "Petrus Hispanus Lectures, II: Radical Probabilism." Actas da Sociedade Portuguesa da Filosofia (forthcoming; and currently available in http://www . princeton.edu/-bayesway/pu/Lisbon.pdf). Kemeny, 1. 1955. "Fair Bets and Inductive Probabilities." Journal o/Symbolic Logic 20:263-273. Lehman, R. 1955. "On Confinnation and Rational Betting." Journal ojSymbolic Logic 20:251262. Lehrer, K. and Wagner, C. 1981. Rational Consensus in Science and Society. Dordrecht: Reidel. Ramsey, F. 1990. "Truth and Probability." In Philosophical Papers ofF P Ramsey, D. H. Mellor, ed., Cambridge: Cambridge University Press. Roberts, F. 1976. Discrete Mathematical Models. Englewood Cliffs: Prentice-Hall. Shafer, G. 1976. A Mathematical Theory oj Evidence. Princeton: Princeton University Press. Strassen, V. 1964. "MeBfehler und Information." Zeitschri/i fur Wahrscheinlichkeitstheorie 2:273-305. Wagner, C. 1989. "Consensus for Belief Functions and Related Uncertainty Measures." TheOlY and Decision 26:295-304. 1992. "Generalized Probability Kinematics." Erkenntnis 36:245-257. ----. 1997. "Old Evidence and New Explanation." Philosophy ojScience 64:677-691. - - - . 1999. "Old Evidence and New Explanation II." Philosophy oj Science 66:283-288. Walley, P. 1981. "Coherent Lower (and Upper) Probabilities." Technical Report, Department of Statistics, University of Warwick, Coventry, England. - ---'-. 1991. Statistical Reasoning with Imprecise Probabilities. London: Chapman and Hall.

TRUSTWORTHINESS

Chapter 10 LEHRER, REID, AND THE FIRST OF ALL PRINCIPLES James Van Cleve Brown University

Weare indebted to Keith Lehrer for his groundbreaking work on the philosophy of Thomas Reid. He has done a great deal to make the interest and importance of Reid's philosophy clear. I would like to thank him for this, and also to raise certain questions concerning his interpretation of Reid's epistemology. I shall be especially concerned with Lehrer's view that one among Reid's principles of common sense stands out as an indispensably important metaprinciple. In Essay VI, Chapter 5 of the Essays on the Intellectual Powers of Man, Reid presents us with a list of "first principles of contingent truths." Some of these principles are purely or primarily metaphysical; for example, Principle 2 tells us that thoughts require a thinker. But others are plainly intended to have epistemological significance, proclaiming the trustworthiness of consciousness (Principle 1), memory (Principle 3), perception (Principle 5), our faculties in general (Principle 7), our beliefs concerning the minds of others (Principles 8 and 9), testimony (Principle 10), and induction (Principle 12). My concern here is with the proper understanding of the epistemological principles, about which I shall discuss three issues in particular. First, are the epistemological principles on Reid's list principles of truth or principles of evidence? Second, are they principles that must themselves be known if knowledge is to arise in accordance with them? Given Lehrer's interpretation of the principles, this amounts to the question whether knowers must have knowledge of the reliability of their own cognitive faculties. Third, what special role is played by Reid's Principle 7, which says that our natural faculties are not fallacious? This is the principle that 155 E.1. Olsson (ed.), The Epistemology of Keith Lehrer, 155-172. © 2003 Kluwer Academic Publishers.

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THE FIRST OF ALL PRINCIPLES

Lehrer calls the keystone of Reid's system, of crucial importance for the way in which it supports the other elements and itself as well.

1.

DOES REID GIVE US PRINCIPLES OF TRUTH OR PRINCIPLES OF EVIDENCE?

According to Lehrer, Reid's principles are in the first instance principles of truth rather than principles of evidence. He writes, "When one considers the first principles Reid articulates, one finds beliefs telling us about truth instead of evidence.'" He holds that in the end Reid's principles do add up to a theory of evidence, but that is because "evidence for Reid just is information about what is true or false.,,2 He elaborates as follows: The first principles state that the convictions of our faculties are true rather than evident, but the information that our convictions are true is the evidence that grounds them. These first principles are, therefore, principles of evidence as well as principles oftruth.3 To anticipate Lehrer's answer to the second of my three questions, I believe he thinks Reid's principles are principles of evidence only in so far as the subject knows them to be true. I am going to propose an alternative interpretation according to which Reid's principles are principles of evidence in their own right, regardless of whether the subject has any knowledge of them. We must begin by answering the question, What is a first principle? As the name implies, it is a principle that comes first in all reasoning or inquiry; that is to say, it is a principle on which we base other beliefs, but which is based on nothing in turn. In company with tradition going back to Aristotle, Reid thinks that a principle is fit to play this role only if it is self-evident: It is demonstrable, and was long ago demonstrated by Aristotle, that every proposition to which we give a rational assent, must either have its evidence in itself, or derive it from some antecedent proposition. And the same thing may be said of the antecedent proposition. As, therefore, we cannot go back to antecedent propositions without end, the evidence must at last rest upon propositions, one or more, which have their evidence III themselves, that is, upon first principles. (EIP 6.7, p. 685)4

Reid affirms the self-evidence of first principles in many other passages as well, including this one:

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There is no searching for evidence; no weighing of arguments; the proposition is not deduced or inferred from another; it has the light of truth in itself, and has no occasion to borrow it from another. Propositions of the last kind, when they are used in matters of science, have commonly been called axioms; and on whatever occasion they are used, are called first principles, principles of common sense, common notions, self-evident truths. (ElP 6.4, p. 593, with a paragraph break omitted) I shall take it, then, that the central trait of first principles is their self-evidence. A cautionary note: I do not necessarily equate Reid's epistemological principles with first principles. As already noted, there are some first principles (e.g., axioms of mathematics or metaphysics) that are not epistemological principles. More significantly, I believe one should be open as well to the converse possibility that Reid's epistemological principles are not first principles themselves-that they specify first principles without being first principles. So the questions I raise in this section and the next about Reid's epistemological principles are not necessarily questions about principles he regards as first principles. With this in mind, let us tum to the question whether the epistemological principles in Reid's list are principles of truth or principles of evidence. I think the answer depends on a crucial but little noted scope ambiguity in the wording of Principle 1 and several other of the principles as well. Here is how Reid formulates Principle 1: First, then, I hold, as a first principle, the existence of every thing of which I am conscious. (EIP 6.5, p. 617) Two preliminary observations are necessary. First, by 'consciousness' Reid means that by which we have knowledge ofthe operations of our own minds; it is roughly equivalent to introspection. Second, when Reid says "if I am conscious of a certain thought, it exists," we may just as well say "if I am conscious that I am thinking thus and so, then I am thinking thus and so." That will facilitate symbolization without distorting Reid's views. The ambiguity to which I wish to call attention may now be brought out by the following two ways of symbolizing Principle 1 (where 'Cp' is short for 'I am conscious that p'):

lA. It is a first principle that (P)(Cp -> p). lB. (p)(Cp -> it is a first principle thatp).

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Notice that what 1A specifies as a first principle is a principle oftruth-a single principle laying down that all the deliverances of consciousness are true. By contrast, 1B is a principle laying down that each of the deliverances of consciousness is itself a first principle. Unlike lA, which gives us one general first principle, 1B gives us many particular first principles I believe the same ambiguity characterizes Reid's other epistemological principles as well. The principle about perception, for example, with 'Pp' abbreviating 'I perceive thatp', could be understood in either of the following ways: SA. It is a first principle that (P)(Pp -> p). 5B. (P)(Pp -> it is a first principle thatp). The relevance of this ambiguity to our question in this section should be obvious. If the first style offormulation of each principle is correct, then Reid's epistemological principles are in the first instance principles of truth, affirming the reliability of our various faculties. They would amount to principles of evidence only in the company of further assumptions connecting evidence with truth, such as Lehrer's assumption that evidence is information concerning what is true and false. s But if the second style of formulation is correct, Reid's epistemological principles are principles of evidence in their own right (despite not overtly containing the term 'evidence '). They are epistemological principles attributing first-principle status to the propositions in various classes (those attested by consciousness, memory, perception, and so on), and as we have seen, such status is to be explicated in terms of self-evidence. So Reid's epistemological principles would be principles specifying what count as first principles, and it would be a further question whether they are first principles themselves. Although Lehrer does not explicitly consider the difference between 1A and 1B, I believe his discussion of Reid's epistemological principles presupposes a reading of them in the A style. He takes Reid's epistemological principles to be first principles, and he says that these principles "state that the convictions of our faculties are true rather than evident.,,6 Both of these things are in keeping with the A style. My own view (for which I have argued at length elsewhere) is that although Reid himself may not have been entirely clear about the difference between the A and the B styles, he says many things that favor a reading of his epistemological principles in the B style. 7 My purpose here is not to discuss further the relative merits of the A and B readings, but to explore some of the facets of Lehrer's interpretation that go naturally with his A reading of the principles. Suffice it to say that although both Lehrer and I think that Reid's epistemological principles amount in the end to principles of evidence, I take them to be self-sufficient principles of evidence in a way that he does not.

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This difference between us is connected with a difference on another point, to which I now turn.

2.

MUST A KNOWER KNOW THAT HIS FACULTIES ARE RELIABLE?

If Reid's epistemological principles are construed in the way I suggest, there is a sense in which he is an epistemological externalist. It is this: the mere fact that a proposition is a deliverance of perception, memory, or consciousness suffices to make that proposition evident. In order to know that there is a tree in front of one, for example, one need only perceive that there is. Nothing else is necessary. In particular, it is not necessary that the subject know anything about the reliability of sense perception. He need take no thought of that. For the externalist Reid, consciousness, memory, and perception are knowledgeconferring (or at least evidence-conferring) factors that do their job regardless of whether the subject knows anything about their justificatory power. There are many places in Reid where I believe the externalist strain in his thinking is prominent. For example, he says that when light from an object strikes the lower portion of one's retina, that gives one knowledge that the object lies in an upward direction from the eye (Inq.6.12, p. 124-25).8 More generally, he says that signs produce "knowledge and belief' of the things they signify (Inq. 6.24, pp. 190ff.). For example, by a law of our constitution, certain tactile sensations produce in us the belief in a hard, extended object; this belief can be knowledge even for one who has no knowledge that such sensations are reliably connected with such objects. Lehrer has always been opposed to externalist views in epistemology, however, and he finds Reid to be no less opposed: Reid is not a reliabilist of the sort Goldman describes. It would be possible for a belief to be a product of a reliable belief-forming process without our having any idea that this was so, without, that is, our having any information about the trustworthiness of the belieC The theory of evidence is based on the innate first principles of the mind. It is, however, not sufficient for a belief to be evident that it be a product of an innate principle, even a trustworthy and reliable one. A belief could be the product of such a principle and

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THE FIRST OF ALL PRINCIPLES not be evident for the person because the person had no idea whether the belief originated in a way that is trustworthy or deceptive. In fact, the first principles of our nature not only yield beliefs but also information about those beliefs, to wit, that they are trustworthy and not fallacious in origin. 1o

Lehrer is implying (in disagreement with what I suggested in the opening paragraph of this section) that in order to be justified in believing that there is a tree over there, it is not enough to perceive that there is a tree there, even if we do so in accordance with a reliable innate tendency of our constitution. We must in addition have the idea (or the information) that perception is a reliable source of belief. What is it to have such information? Is it merely to believe that perception is reliable? Or is it something stronger-to believe with evidence and truth, and thus to know, that perception is reliable? Let us consider each of these requirements in turn. First, in order to have knowledge from a source, must we believe that the source is reliable? If so, then the generality of mankind do not know very much, for they are seldom as reflective as that. A child or an unreflective adult may take little thought about the faculties whose deliverances she accepts. I believe that this is Reid's own position, as shown in the following passage: We may here take notice of a property of the principle under consideration [that our faculties are not fallacious] that seems to be common to it with many other first principles ... and that is, that in most men it produces its effect without ever being attended to, or made an object of thought. No man ever thinks of this principle, unless when he considers the grounds of skepticism; yet it invariably governs his opinions. When a man in the common course of life gives credit to the testimony of his senses, his memory, or his reason, he does not put the question to himself, whether these faculties may deceive him; yet the trust he reposes in them supposes an inward conviction, that in this instance at least, they do not deceive him. (EIP 6.5, p. 632) It is another property of this and of many first principles that they force assent in particular instances more powerfully than when they are turned into a general proposition. (Ibid.)

Mindful of passages such as these, Lehrer qualifies the requirement that subjects must believe in the reliability of their own faculties. He says that principles such as 'What I perceive to be the case is generally so' must be

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"operative" in us even if we do not explicitly believe them, II and that general principles must be "in us" in the sense that they cause us to believe their particular instances. 12 In what sense do we have general beliefs that cause us to have beliefs in their particular instances? Two observations will help to clarify this matter. First, what Reid and Lehrer mean by an "instance" of a general belief is really an instance of its consequent, obtainable by subsumption (i.e., universal instantiation and modus ponens). If the general proposition is' All deliverances of perception are true', symbolizable as '(P)(Pp -> p)', then an instance of it would be 'there is a tree over there' (if that is what I am now perceiving)Y Second, there is a sense in which one believes implicitly that all Fs are Gs simply by having the disposition to believe, concerning anything one believes to be F, that it is G. In symbols, we could say that one has an implicit belief in '(x)(Fx -> Gx)' if one has the disposition expressed by 'BFx -> BGX.'I4 Ifone has such an implicit belief, one will be caused to believe instances of the consequent of'(x)(Fx -> Gx)' whenever one believes instances of its antecedent. Even if a man never framed in his mind the proposition that perceptual beliefs are generally true, he might still be so constituted that whenever he believes he perceives that p, he also believes that p. (Alternatively, if we wish to accommodate the possibility that sometimes we perceive things without believing that we do, we could say that a general belief in the reliability of perception is operative in S if S is so constituted that whenever he is conscious of perceiving that p (e.g., that there is a tree over there), he believes that pys We have now identified one plausible sense in which ordinary subjects believe in the reliability of their faculties. Even if they do not have general propositions such as 'When I perceive something to be the case, it is the case' explicitly before their minds, their opinions are governed by them, in the sense that whenever they are aware offalling under the antecedent, they will believe the consequent. Let us now tum to the stronger requirement envisioned above-that to know something through a faculty, you must know that the faculty is reliable. I believe that Lehrer accepts this requirement and that he thinks Reid does, too. Of course, if the sense in which we believe in reliability is only the implicit sense just identified, the sense in which we have knowledge of reliability would presumably be implicit in a corresponding sense. I will ignore this complication here. Following Stewart Cohen, the requirement we are now considering may be put thus: I6 (KR) A potential knowledge source K can yield knowledge for a subject S only if S knows K is reliable.

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Given the way Lehrer understands Reid's epistemological principles (as principles affirming that the deliverances of our faculties are generally true), th is would mean that Reid's epistemological principles contribute to a subject's knowledge only if they are themselves known. It takes but little reflection to see that KR is actually quite a stringent requirement-one that threatens to lead to skepticism. It would lead indeed to skepticism if we made two further assumptions. The first assumption is that what KR lays down as a necessary condition of knowledge through K is a prior condition of such knowledge, that is, that S can know through K that p only if S first knows that K is reliable. The second assumption is that knowledge of the reliabiJity of a source can come about in one way only, namely, by inference from premises obtained from that very source. To illustrate, Descartes tried to establish the reliability of clear and distinct perception by proving the existence and veracity of God, but could obtain the premises for the proof only through clear and distinct perception itself. Others have envisioned proving that a faculty is reliable by appeal to the reliable operation of that faculty in the past-a so-called track record argument-but obtaining the premises for the track-record argument requires using the faculty on whose behalf it is conducted. 17 In sum, it seems that we must know that various of the particular deliverances of a source are true before we can know that the source is reliable. Putting these points together, we would find ourselves in the following predicament: (1)

(2)

We can know that a deliverance of K is true only if we first know that K is reliable. We can know that K is reliable only if we first know, concerning certain of its deliverances, that they are true.

If (1) and (2) are both true, skepticism is the inevitable consequence. Clearly, if we cannot know either of two things without knowing the other first, we must remain ignorant of both of them. How would Reid, the great foe of the skeptic, respond to this threat? If Reid is an externalist, as I have suggested he is at least some of the time, he would deny KR and with it proposition (l). Consciousness, memory, perception, and our other faculties give us knowledge of their deliverances even if we are initially ignorant of their reliability. But Lehrer's Reid is not an externalist, and it must be admitted that there are places where Reid seems to accept a requirement like KR. Here is a notable passage: If any truth can be said to be prior to all others in the order of nature, this [that our faculties are not fallacious] seems to have the best claim; because in every instance of assent, whether upon

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intuitive, demonstrative, or probable evidence, the truth of our faculties is taken for granted, and is, as it were, one of the premises on which our assent is grounded. (EIP 6.5, p. 631-32). Knowledge of anything whatever, Reid seems to be saying, depends on knowledge of a special fact-that our faculties are reliable. Is he saying that knowledge of anything requires knowledge that all of our faculties are reliable, or only that knowledge through a given faculty requires knowledge that that faculty is reliable?18 Either way, the question arises how we are to acquire knowledge of the special fact. If Reid accepts proposition (2) alongside proposition (1), he will have made such knowledge impossible. But Lehrer's Reid, as we shall see, evades this difficulty by rejecting proposition (2). I shall return to this matter after discussing Lehrer's interpretation of Principle 7.

3.

DOES PRINCIPLE 7 PLAY A SPECIAL ROLE?

Here is how Reid formulates the seventh of his principles: 7thly, Another first principle is, that the natural faculties, by which we distinguish truth from error, are not fallacious. (EIP 6.5, p. 630) According to Lehrer, Principle 7 is the most important principle of al1. 19 It is special in two ways. First, it is a metaprinciple, affirming the truth of all the others.zo Second, it is a looping principle. "The principle vouches for itself. It loops around and supports itself."2l For these reasons, Lehrer calls this principle "the keystone principle of the first principles."n He also calls it "the first first principle.,,23 But if Principle 7 is really the first in importance, why does it occur seventh in a list of twelve? One would have expected that if Principle 7 plays a pre-eminent role, Reid would have put it either at the top or bottom of his list or perhaps outside the list altogether, rather than burying it in the middle. There are ways of understanding Principle 7 as co-ordinate with the other principles, treating of just certain faculties among others, and thus deserving of its place in the middle ofthe list. Philip de Bary has noted that the clause "by which we distinguish truth from error" may have been intended by Reid as a restrictive clause, singling out a subset of the faculties, rather than as a parenthetical gloss on what all faculties do. 24 And yet do not all faculties enable us to distinguish truth from error, informing us that some things are true and others false? So what restriction could Principle 7 be introducing?

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One suggestion for a restricted Principle 7 would be to take the faculties "by which we distinguish truth from error" to be second-order faculties, that is, faculties whereby we judge of other faculties. 25 Ifwe do this, Principle 7 would be a principle about meta-faculties, but it would not necessarily be a metaprinciple. Nor would it be a principle of supreme generality, for it would concern some faculties among others, even if those faculties are of special importance. Against this suggestion, however, is the fact that Reid twice uses the phrase "until God give us new faculties to sit in judgment upon the old" (6.5, p. 631; 6.7, p. 678), implying that we have nothing to judge of our faculties but those faculties themselves. Another suggestion would be to take Principle 7 as concerned with reasoning, which is not mentioned elsewhere in Reid's list of principles. 26 Reasoning, Reid tells us, is "the process by which we pass from one judgment to another" (p. 475 in Hamilton). There is some support for this suggestion in the fact that many of Reid's illustrations of Principle 7 are cases of reasoning. For example, immediately following his enunciation of Principle 7, he says, "If any man should demand a proof of this it is impossible to satisfy him ... because to judge of a demonstration, a man must trust his faculties" (EIP 6.5, p. 630; emphasis mine). He follows this up by observing that the very point in question in Principle 7 is whether reasoning may be trusted. These remarks are not decisive, however. If Principle 7 concerned all our faculties, as Lehrer holds, it would concern reasoning, too, so Reid could still make his point that it would beg the question to offer reasoning in support of Principle 7. Moreover, as we read further in Reid's commentary on Principle 7, we find him saying that it is concerned with "all our reasoning and judging powers" (pp. 630 and 632), which suggests a considerably broader scope for Principle 7. But how much broader? De Bary suggests a broader but still restricted scope for Principle 7. Noting that Reid devotes separate Essays in the Intellectual Powers to perception, memory,judging, and reasoning, he proposes that the scope of Principle 7 is just judging and reasoning, not our faculties in general. Against this suggestion, however, is the fact that Reid views perception and memory as special cases of judgment. He says, for example, "There is no more reason to account our senses fallacious, than our reason, our memory, or any other faculty ofjudging which nature has given us" (EIP 2.22, emphasis mine). Confirming this point, Essay 6, "Of Judgment," makes points applicable to all our faculties; indeed, it is in that Essay that we find the list of principles that is our topic in this essay. Moreover, as we read Reid's thirteen paragraphs of commentary on Principle 7, I think it becomes fairly clear that Principle 7 is meant to cover all our faculties. The trust we repose in our senses, our memory, our consciousness, and our reason are all said to be instances ofthe general trust that is affirmed in Principle 7.27

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I shall assume with Lehrer, then, that Principle 7 does indeed concern all of our cognitive faculties-not just some specially delineated faculty or faculties. And yet the question remains: In what way does Principle 7 go beyond the other principles on Reid's list? Why is it not merely redundant-perhaps simply a device enabling Reid to make points concerning all the principles by discussing a single one? To this question, Lehrer's answer is that Principle 7 is a metaprinciple, affirming the truth of the other principles, and a looping principle, affirming the truth of itself as well. In this last way it goes beyond the other principles. If we take Reid's formulations at face value, however, there does not appear to be anything particularly "meta" about Principle 7. The sequence

Consciousness is reliable. Memory is reliable. Perception is reliable. All our faculties are reliable. is comparable with the sequence My dogs are friendly. My cats are friendly. My birds are friendly. All my pets are friendly. The last item on each list does not seem to be much more than a summary of what has gone before. If Principle 7 goes beyond the other principles, it is only by virtue of implying either that I have no faculties not already mentioned or, if I do, that they are reliable, toO.28 Nonetheless, the "meta" and "looping" character of Principle 7 may be brought out more clearly if we rewrite Principle 7 in a way Lehrer has proposed. Principle 7 may be recast, he suggests, as a principle affirming that all first principles are true. 29 So construed, Principle 7 does indeed convey what the other principles convey (that consciousness is reliable because Principle I is true, memory reliable because Principle 3 is true, and so on). But Principle 7 also conveys more, because it is itself a first principle. It therefore implies its own truth by way of self-subsumption: All first principles are true (= Principle 7). Principle 7 is a first principle (i.e., it is a first principle that all first principles are true).

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THE FIRST OF ALL PRINCIPLES Therefore, Principle 7 is true.

The self-subsuming character of Principle 7 may not have been obvious in Reid's formulation, because 'all our faculties are reliable' talks of faculties rather than principles. 30 But Lehrer's rewrite makes the self-subsuming feature manifest, and it is precisely this feature, he thinks, that enables Principle 7 to play its keystone role. I have two questions about Lehrer's rewrite. First, is it a legitimate transcription of Reid's original? 'All first principles are true' would be equivalent to' All our faculties are reliable' provided the following biconditional were true: P is a first principle iff P is a principle affirming the reliability of some faculty or faculties of ours. The right-to-left half of this biconditional depends on whether it can be self-evident that a faculty is reliable-a debatable question, but one to which Lehrer clearly thinks Reid would answer yes, as we shall see further below. The left-to-right half ofthe biconditional is problematic. There are first principles that do not affirm reliability (e.g., particular propositions such as there is a tree in front of me, and metaphysical principles such as the thoughts of which one is conscious must be thoughts of a thinker). But I shall assume that we may qualify Lehrer's rewrite of Principle 7 so as to get around this problem. The more interesting question is this: What do we gain by the rewrite? Lehrer's answer is that we obtain thereby a principle that explains its own truth. He is worried by the prospect of epistemic surds-that is, epistemological principles for which there is no explanation. Given a choice between a surd and a loop-that is, between an unexplained principle and a principle that explains itself-he would always prefer the 100p.3l By making Principle 7 self-subsuming, do we really enable it to play this special explanatory role? A qualm about this may be engendered by considering the following list: 2 + 2 = 4. Aberdeen is northeast of Glasgow. Water boils at 212 degrees F. All the sentences in this list are true. The concern is that the final sentence is semantically ungrounded, just like the truth-teller sentence, 'this sentence is true'. If one of the sentences preceding it were false, that would make the final sentence false. But if all others on the list are true, whether the last is true comes down to whether it is true, and there seems nothing to determine that. There is nothing to make it true or false, so arguably it is neither. The situation seems similar with Principle 7. If the other first principles are all true, then Principle 7 goes beyond them just to the extent

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that it ventures out over the void, with nothing to sustain a truth value for it. So the worry is that in trying to come up with a keystone principle that explains the others and itself in the bargain, we obtain a principle that explains nothing because it lacks truth value. I do not wish to suggest that there is anything automatically defective about general principles that subsume themselves. All necessary propositions are true is itself a necessary proposition, and therefore may be subsumed under itself. But there is no question about its truth value; it is an accepted axiom of modal logic. Similarly, everything that God believes is true would be both selfsubsuming and true (indeed, necessarily true) if there were an essentially omniscient and infallible God who believed it. But it is significant that these examples of self-subsuming propositions that are unproblematically true are necessary truths. There is a necessary connection between the properties that figure in antecedent and consequent, and that is what makes them true. Lehrer, however, does not think that Principle 7 is a necessary truth. He thinks that Reid's first principles of contingent truths are themselves contingent. 32 So he does not have this way of alleviating the worry I have raised that under his construal of it, Principle 7 is semantically ungrounded. I shall return to this worry at the end of the next section. It is time to see how two aspects of Lehrer's interpretation of Reid-the KR requirement on knowledge and the endorsement of looping principles-are connected.

4.

FACULTIES THAT VOUCH FOR THEMSELVES

The problem we left hanging at the end of section 2 was this: if we cannot know anything through a faculty without knowing that that faculty is reliable (as required by KR), how can we know anything at all? The problem can be formulated as a pair of premises that jointly entail skepticism: (1)

(2)

We can know that a deliverance of K is true only if we first know that K is reliable. We can know that K is reliable only if we first know, concerning certain of its deliverances, that they are true.

When the problem is posed this way, it is clear that we can avoid skepticism only by denying (1) or (2). An externalist would deny (1), but Lehrer's Reid is no externalist. So let us consider the option of denying (2)-of denying that knowledge of the reliability of a source must be collected from various of the particular deliverances of that source. If not derived from knowledge of its own particular

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deliverances, from what other knowledge could knowledge of K's reliability be derived? One answer is: from no other knowledge. Knowledge of the reliability of our faculties is epistemically basic. That is the answer given by Lehrer's Reid: we know that our faculties are reliable not by deriving this knowledge from any other knowledge, but simply because the reliability of our faculties is self-evident. 33 It is a self-evident first principle that consciousness is reliable; it is likewise a self-evident first principle that perception is reliable; and so on for all our other faculties. So we have a way of breaking the skeptical impasse set up by propositions (1) and (2). We can accept the condition that KR lays down for all knowledge, but affirm that that condition is thankfully met, owing to the first principles of human knowledge. Let us look more closely at the implications of this. For Lehrer's Reid, we are enabled to know that the particular deliverances of sense perception are reliable because it is a piece of basic knowledge, inferred from no other, that sense perception is reliable. We are still entitled to ask: what is the source of this basic knowledge? Presumably, it is not perception itself, which does not yield truths of such generality.34 If only to give the source a name, let us call it intuition. 35 By KR, intuition yields knowledge only if we know that intuition is reliable. What is the source of that knowledge? This time we may answer that it is intuition itself-intuition intuits its own reliability. Indeed, it seems plausible that we must give an answer of that form sooner or later-KR can admit basic knowledge of the reliability of a source only if there is at least one source that gives basic knowledge of its own reliability. But now let's go back to the principle that perception is reliable. How can that be a first principle if knowledge of it depends on the knowledge that some other faculty, namely, intuition, is reliable? Perhaps the answer is something like this: although it would not be evident (or known) that perception is reliable unless it were evident (or known) that intuition is reliable, that is not because the former proposition derives its evidence from the latter. Rather, intuition confers evidence simultaneously on its primary object (in this case, that perception is reliable) and also on its own reliability.36 The Reidian view that is emerging evidently requires that there be certain faculties or sources that deliver knowledge not only of their primary objects, but also of their own reliability. This may be what Reid himself is getting at in a striking passage comparing evidence to light, which follows immediately upon his suggestion that if any truth be prior to all others, it is Principle 7: How then come we to be assured of this fundamental truth on which all others rest? Perhaps evidence, as in many other respects it resembles light, so in this also, that as light, which is the discoverer of all visible objects, discovers itself at the same time:

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so evidence, which is the voucher for all truth, vouches for itself at the same time. (EIP 6.5, p. 632) 37 The idea would be that as light discloses features both of visible objects and itself, so our cognitive faculties disclose features both of their primary objects and ofthemselves-in particular, their own reliability. With this answer, we have drawn close to Lehrer's interpretation of Principle 7. Recall that for Lehrer, Principle 7 undergirds all the others and itself at the same time. It is a principle that affirms its own truth along with the truth of the other principles. We are now suggesting that there are faculties that apprehend their own reliability along with the reliability of other faculties. We have thus arrived at a view structurally similar to Lehrer's, incorporating the same looping strategy he favors. And we have been led to do so in the attempt to show that knowledge is possible even under the tough demands imposed by KR. It is no accident, then, that a philosopher who, like Lehrer's Reid, holds that there is no knowledge through a faculty without knowledge of its reliability, also holds that there are faculties that vouch for their own reliability. It is now time to return to the worry left unresolved at the end of the previous section-that self-subsuming principles of the sort Lehrer favors would be semantically ungrounded. Is there not an analogous worry about selfauthenticating faculties? Suppose that intuition intuits its own reliability-that is, that I have an intuiting whose content is that all intuitings are true. If all other intuitings are true, what would make that one true? As before, I think it would have to be some sort of necessary connection between the properties of being an intuiting and being true. (If it were simply a matter of the individual truth values of all intuitings, ungroundedness would threaten.) Is there plausibly such a connection, and could Lehrer accept it? I noted above that he does not believe that Reid's principles are metaphysically necessary truths; he would deny that there is any metaphysically necessary connection between being an intuiting and being true. But I expect he might allow that there is a nomologically necessary connection between being an intuiting and being true, and perhaps such a connection would suffice as a truth-maker for the intuiting that all intuitings are true. I leave further exploration ofthat possibility for another occasion.

5.

THE WEB OF SELF-EVIDENCE

There is a side of Lehrer's Reid I have so far left out of account. As we have seen, Lehrer's Reid holds that general principles affirming the reliability of our faculties are evident in themselves and known immediately. But Lehrer also says that particular deliverances of our faculties, such as the beliefthat there is a hard object in my hand, are evident in themselves and known immediately.

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"Our knowledge of both the first principles and the particular beliefs to which they give rise are both immediate .... The [general] principles and [particular] beliefs of common sense fit together like links in a chain, and he that is not fit to pick up the whole should not attempt to lift up any of the parts.,,38 Here Lehrer seems to be telling us that general principles and particular beliefs are both self-evident, but at the same time, that neither generals nor particulars would be evident unless both were part of our system of belief. Is that a consistent combination? Lehrer's Reid is beginning to sound like a coherentist, for whom particular beliefs and general beliefs become evident together once a wide enough body of mutually supporting beliefs is in place. 39 Yet coherence theories are normally taken to repudiate the category of the self-evident, while Lehrer's Reid asserts that plenty of things are self-evident, general principles and particular beliefs alike. What are we to make ofthis? Suppose we say that one belief is epistemically prior to another (or that beliefs in one class are epistemically prior to those in another) iff the latter belief(s) derive their evidence from the evidence of the former, in such fashion that the latter beliefs could not be evident unless the former beliefs were already evident. Suppose we then say that a belief is self-evident iff it is evident, but there is nothing epistemically prior to it. We could then say that a coherence theory that rejects the very idea of epistemic priority is a theory that, rather than repudiating the category of the self-evident, makes every evident belief selfevident. Reid, while not going this far, could hold that particular beliefs and general beliefs depend on each other for their evidence without beliefs of either sort being prior to beliefs of the other sort; thus particulars and generals would both be self-evident. This could be one way in which Reid, as Lehrer says, transcends the dichotomy between foundational ism and coherentism. 40

ENDNOTES 1 Keith Lehrer, Thomas Reid (London: Routledge, 1989), p. 197. This book is cited hereafter as Reid. 2 Reid, p. 198. ) Reid, p. 157. 4 This abbreviates Essay 6, Chapter 7, of Reid's Essays on the Intellectual Powers of Man. My page references are to the edition edited by Baruch Brody (Cambridge, Mass.: MIT Press, 1969). 5 Another assumption that would convert lA and the other A-style principles to principles of evidence is a reliability theory of justification, but Lehrer and Lehrer's Reid both repudiate reliability theories. (, Reid, p. 157. 7 James Van Cleve, "Reid on the First Principles of Contingent Truths," Reid Studies, 3 (1999), 3-30.

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8 This abbreviates Chapter 6, Section 12, of Reid's Inquiry into the Human Mind. My page references are to the volume edited by Derek R. Brookes (Edinburgh: Edinburgh University Press, 1997). 9 Reid, p. 198. IOReid,p.187. 11 Lecture at the NEH Seminar on Thomas Reid, Brown University, August, 2000. 12 Keith Lehrer, "Chisholm, Reid, and the Problem ofthe Epistemic Surd," Philosophical Studies, 60 (1990), 39-45, at p. 40. This article is cited hereafter as "Surd." 13 A substitution instance of the generalization '(x)(Fx -> Gx)' would be the conditional 'Fa-> Ga'; a confirmation instance of it would be the conjunction 'Fa & Ga' (or perhaps an object that is both F and G). What Reid and Lehrer mean by an instance is neither ofthese things, but simply 'Ga'. 14 Ernest Sosa offers an analysis of "implicit commitments" along these lines in Ernest Sosa and James Van Cleve, "Thomas Reid," in The Blackwell Guide to the Modern Philosophers from Descartes to Nietzsche, edited by Steven M. Emmanuel (Oxford: Blackwell, 2001), pp. 179-200, beginning on p. 190. For the more radical view that general belief is never anything over and above such BFx -> BGx dispositions, see David Armstrong, Belief, Truth, and Knowledge (Cambridge: Cambridge University Press, 1973), ch. 6. 15 Reid may be committed to rejecting this possibility. In his account ofthe system ofLeibniz, he explicitly disapproves of Leibniz's distinction between perception and apperception. "As far as we can discover, every operation of our mind is attended with consciousness, and particularly that which we call the perception of external objects .... No man can perceive an object, without being conscious that he perceives it" (EIP 2.15, pp. 236-37 in Brody). In another place (EIP 3.1, p. 325), he says that consciousness is always attended with belief of that whereof we are conscious. Putting these together, it follows that we never perceive without believing that we perceive. 16 Stewart Cohen, "Basic Knowledge and the Problem of Easy Knowledge," forthcoming in Philosophy and Phenomenological Research. 17 See William P. Alston, "Epistemic Circularity," Philosophy and Phenomenological Research, 47 (1986), 1-30. 18 As Ernest Sosa points out to me, there is a further ambiguity in the first disjunct: is it the de dicto knowledge that all my faculties are reliable, or the de re knowledge, concerning each faculty, that it is reliable? 19 Reid, p. 162. 20 Reid, pp. 144, 157, 162, and 187. 21 "Surd," p. 43. 22 "Surd," p. 42. 23 Keith Lehrer, "Reid, Hume, and Common Sense," Reid Studies, 2 (1998),15-25, on p. 15 and elsewhere. 24 Philip de Bary, "Thomas Reid's Metaprinciple," American Catholic Philosophical Quarterly, 74 (2000), 373-83. He reports in note 22 on p. 380 that in Reid's manuscript of the Intellectual Powers at Aberdeen University Library, there are no commas surrounding "by which we distinguish truth from error." 25 I thank Gideon Yaffe and Sue Cox for this suggestion. 26 I thank Alan Hazlett, Nick Treanor, and Ali Eslami for this suggestion. 27 I have in mind the twelfth paragraph of commentary on Principle 7. This paragraph may not be decisive, however, since Reid says he is noting a property that Principle 7 has in common with other principles, and it is just possible that the trust we repose in our senses, our memory, and our reason may illustrate the implicit belief we have in principles other than Principle 7. 28 So that Principle 7 not convey less information than the preceding principles, I am assuming that a reference to the faculties already mentioned is implicit-'the above-mentioned faculties, as well as any others that I possess, are reliable'.

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29 Lecture at the NEH Seminar on Thomas Reid, Brown University, August, 2000. Lehrer's actual formulation was 'all first principles are trustworthy,' where being trustworthy implies both being evident and being true. The fact that trustworthiness implies truth generates the worry about ungroundedness that I raise in the text. 30 Ifwe render 'all our faculties are reliable' as 'all deliverances of our faculties are true', however, we would obtain a principle that is self-subsuming provided it is itself a deliverance of our faculties. 31 Keith Lehrer, Self-Trust (Oxford: Clarendon, 1997), pp. 22-23. 32 The "first principles of contingent truths" are so called because they make knowledge of contingent truths possible; this leaves it open whether they are themselves necessary or contingent. It is clear from Reid, p. 157, however, that Lehrer takes them to be contingent. Moreover, to the extent that Lehrer construes the principles as attributing trustworthiness and not just truth, he has a principled reason for regarding them as contingent: he believes that epistemic properties never supervene with metaphysical necessity on nonepistemic properties. On this point, see Chapter 3 of Self-Trust. 33 "Surd," p. 40, and "Reid, Hume, and Common Sense," pp. 22-23. 34 Here I may disagree with Lehrer, who says at p. 22 of "Reid, Hume, and Common Sense" that the first principle about perception comes from the faculty of perception itself. 35 Perhaps a good Reidian name for it would be 'common sense', for Reid tells us that "the sole province of common sense" is "to judge of things self-evident" (EIP 6.2, 567). 36 We see here, by the way, that the Reid who gets around the skeptical impasse by denying (2) must also deny (1). Though he accepts KR, he denies that to have knowledge through K you must have knowledge of K's reliability first. Otherwise, there could be no such thing as basic knowledge of the reliability of a source. Rather, there are cases in which knowledge through K and knowledge ofK's reliability arise simultaneously. 37 Lehrer has drawn on this passage for a somewhat different purpose. He poses a question about Reid from Chisholm: "How can we tell that a belief is evident if not by appeal to a general principle?" He cites the paragraph about light as Reid's answer, glossing it as "the evidence of some beliefs is itself evident.... Ifthere are some beliefs whose evidence is evident to us, we have no need for a criterion to pick them out as evident" ("Surd," p. 41). 38 "Surd," p. 40; see also Reid, pp. 199-200. 39 In the article cited in footnote 16, a coherence theory is Cohen's way around the impasse created by (1) and (2). In effect, he denies both of them, holding that knowledge of the reliability of a source and knowledge of the truth of its particular deliverances depend on each other without either being prior to the other. 40 "Reid, Hume, and Common Sense," p. 16.

Chapter 11 SELF-TRUST AND THE REASONABLENESS OF ACCEPTANCE G. J. Mattey University a/California, Davis

Keith Lehrer's theory of knowledge has undergone considerable transformation since the original version he presented in his 1974 book Knowledge [2]. Among the original elements of the theory, belief has been replaced by acceptance, subjective probability by reasonableness, the doxastic system by the acceptance system, and beating competitors by answering objections. New elements, such as the preference system and the reasoning system, have been added. These changes have enhanced the depth and plausibility of the theory. A feature added in the first edition of Theory of Knowledge [3], the "principle of the trustworthiness of acceptance," also known as "(T)", has by contrast been treated by Lehrer in a way that arouses suspicion. The most recent formulation appears in the second edition of Theory of Knowledge: "I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true" ([6], p. 138). Lehrer makes a case, which will be examined below, that one's acceptance of (T) contributes to the reasonableness of everything that one accepts. By virtue of its form, if principle (T) is accepted with the objective of accepting it just in case it is true, it applies to itself. Then, given its general contribution to the reasonableness of what one accepts, accepting (T) contributes to the reasonableness of accepting (T): "If a person accepts (T), then her acceptance of (T) itself will have the result that it is reasonable for her to accept (T)" ([6], p. 142). Lehrer regards such direct self-application of (T) to be both natural and illuminating. He recognizes that it generates a circle, or "loop," but he claims that the circularity is not vicious, because the loop is explanatory rather than argumentative ([5], p. 136). This paper will examine the role of the principle 173 E.J. Olsson (ed.), The Epistemology of Keith Lehrer, 173-194. © 2003 Kluwer Academic Publishers.

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of trustworthiness in making acceptance reasonable and the way in which it might make itself reasonable.

1.

ACCEPTANCE, JUSTIFICATION, AND KNOWLEDGE

Lehrer intends his theory of knowledge to provide an account of an intellectual sort of know Iedge, one that presupposes a healthy degree of cognitive sophistication. In particular, this kind of knowledge is more than the mere possession of correct information, requiring in addition a recognition of the information as being correct. "It is information that we recognize to be correct that yields the characteristically human sort of knowledge that distinguishes us as adult cognizers from machines, other animals, and even our infant selves" ([6], p. 7). Information recognized as correct "is inextricably woven into reasoning, justification, confirmation, and refutation" ([6], p. 6). A person who possesses correct information must, in order to have knowledge of the type Lehrer is trying to analyze, take the information to be correct. But recognizing information to be correct involves more than this. A person may take information to be correct without any purpose. 1 Purposive recognition of information as correct is what Lehrer calls "acceptance." It is the taking of information to be true in order to satisfY some specific objective. This requires evaluating how well the act of taking the information to be true furthers the objective. Lehrer claims that such evaluation can take place without reflection. "Positive evaluation may occur without reflection when reflection would be otiose and would leave unchanged our intellectual and practical attitudes concerning what we accept" ([4], p. 4. Cf. [6], p. 40.). The kind of acceptance that can be knowledge of the sort to be captured by Lehrer's theory is one based on an evaluation in terms of "the epistemic purpose" of obtaining true information and rejecting false information ([6], p. 14). (We shall call this kind of acceptance "epistemic acceptance.") The purpose is in general to maximize the possession of true information and minimize the possession of false information. The most obvious way in which the evaluation would occur is through reflection on whether acceptance helps to fulfill the epistemic purpose. But since Lehrer claims that acceptance may not require reflection, it appears that he needs to postulate a default mechanism for acceptance in mundane matters so that reflection is called for only when use of that mechanism is inappropriate. 2 If reflection is involved, there is a decision to be made by an epistemic agent whether or not to accept a given piece of information as being true, in order to fulfill the epistemic purpose. 3 When I consider accepting something, I have two options, acceptance and non-acceptance. When I accept something, I have,

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in effect, raised the question, to accept or not to accept, and answered the question with a positive evaluation. ([4], p. 10) The evaluative criterion governing epistemic acceptance is that of "reasonableness." It can be more or less reasonable to accept epistemically a given piece of information. The minimal degree of reasonableness required for a positive evaluation would be that it be more reasonable to accept the information as being true than not to accept the information. 4 Acceptance might be anywhere from barely to massively more reasonable than withholding acceptance. If an epistemic agent is to know that the information he accepts is true, then the reasonableness of accepting as opposed to withholding should be very high. Otherwise, the correctness of his decision to accept would be fortuitous. 5 It is tempting to say that if the reasonableness of acceptance meets a certain threshold level, then the acceptance is justified and thus meets a condition for knowledge of the type under consideration. Lehrer realized from the beginning that such a simple condition for justification is subject to the lottery paradox. 6 To avoid this problem, he considered other pieces of information whose acceptance would make the acceptance of a given piece of information less reasonable. These competing pieces of information he now calls "objections" to the information whose acceptance is at issue. Lehrer uses this device to base his definition of justification on the notion of reasonableness while avoiding the lottery paradox. A piece of information is subjectively or "personally" justified just in case the agent has a way of dealing with all objections. 7 If the information is also true and the acceptance of it is objectively justified, it amounts to knowledge. 8 The idea that justification consists in the ability to deal with all objections has a certain appeal, especially with respect to the kind of knowledge which is the target of Lehrer's theory. Paradigmatically, knowledge is the outcome of critical inquiry; it is what emerges, or at least would emerge, from the crucible of intensive dialectical engagement with objections. 9 If an actual examination of objections is required in each case of acceptance, the range of information that is accepted, and therefore could count as knowledge would be severely limited. On Lehrer's view such an examination is not required. The act of epistemic acceptance does not require any reflection at all, so it does not require that objections be taken into account. Ordinarily, the decision to accept is based on positive evidence for the truth of the information, and objections are considered only when there is some reason to think the information is false or when one is being extra-cautious. 1o Note that from a practical standpoint, consideration of myriad objections would thwart the goal of accepting as many truths as possible. Even when reflection is called for in non-routine cases, generally not all objections are taken into account when making a decision to accept a piece of information as true to help fulfill the epistemic purpose.

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Then the question arises as to how an acceptance can be justified, given that all objections have to be dealt with. The answer is that one must have the resources to deal with objections, whether or not one has taken them into account in the evaluation leading to the act of acceptance. These resources make the acceptance "reasonable," perhaps reasonable enough to count as knowledge. This means that it can be asked post hoc to what extent an acceptance is reasonable, where the answer may involve resources that were not drawn upon in the act of acceptance. So we need to make a distinction between the act of accepting and the ongoing commitment to truth that can also be called acceptance. At one point in time, acceptance is a mental act of committing to the truth of a piece of information, in order to help fulfill the epistemic purpose. Reasonableness plays the role of a criterion for making the commitment. At a later point in time, acceptance is a commitment already made. As such, it is a candidate for knowledge. The reasonableness of already-made acceptance might be understood in terms of whether it is permissible to retain it or perhaps whether the act of acceptance would be called for given the information one has at the time. In discussing the reasonableness of acceptance, Lehrer draws on both of these aspects without clearly indicating which one is in play.

2.

REASONABLENESS

What does it mean to say that it is reasonable, to some degree, for a person to accept the information that p to fulfill the epistemic purpose of obtaining truth and avoiding error? Lehrer treats reasonableness as a primitive notion, though he does note a relation between reasonableness and the epistemic purpose. For the information thatp to be reasonable (to some degree) to be accepted, it must be subjectively probable to a certain degree, which promotes the goal of avoiding error. Conversely, accepting information that p is made more reasonable as it is more informative, which promotes the goal of obtaining truth ([6], p. 144-145). Typical of somewhat risky, but highly informative, information are "major scientific claims, those concerning galaxies, genes, and electrons" ([6], p. 145). How reasonable it is to accept epistemically a piece of information would seem on the face of it to be a complex matter, which is perhaps not easily determined. Lehrer sidesteps this issue by simply assuming that "we are able to tell, at least intuitively, when it is more reasonable to accept one thing than the other" ([6], p. 128).11 This allows him to make reasonableness the determining factor in any evaluation that results in the acceptance of the information that p to fulfill the epistemic purpose. "I confront the question of whether or not to accept some information that I receive," and I answer the question on the basis of "how reasonable it is to accept the information in comparison to other competing considerations" ([6], p. 126).

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The sole source of reasonableness, on Lehrer's account, is the agent's "evaluation system.,,12 Several components together make up the evaluation system, of which one, the "acceptance system," is relevant to the present discussion.13 This is the repository of information a person has already taken to be true for the purposes of obtaining truth and avoiding error. As the evaluation system is internal to the agent, no external factors contribute to the reasonableness of acceptance. Lehrer describes the role of the acceptance system in terms of its contribution to the reasonableness of the act of accepting. "In deciding whether to accept something or not at the present moment, reason requires the use of relevant information I have accumulated in the quest for truth. That information is contained in my acceptance system" ([6], p. 125).14 The evaluation system enables the evaluation to take place by "informing" or "telling" the agent the extent to which the information available to him is reasonable and how reasonable the information under evaluation is relative to it ([6], p. 125).15 Lehrer's account of how the evaluation system makes acceptance reasonable does not describe what makes an already-held acceptance reasonable. The account can be applied in a couple of different ways to an acceptance one has already made. The evaluation system might inform the agent about the reasonableness of retaining the acceptance, or it might inform him about how reasonable a fresh acceptance would be in light of the information he now has. When the acceptance system makes it reasonable for a person to accept some information p to fulfill the epistemic purpose, it can be described as providing evidential support for the acceptance. Because Lehrer makes the acceptance system the sole means by which support is conferred, the relation of support is mutual or reciprocal. The accepted information p is supported by the rest of the acceptance system. The reasonableness of accepting any information q contained in the rest of the acceptance system is supported by the remainder of the acceptance system, which includes the acceptance ofp. The mutual "fit" of information within an acceptance system will henceforth be referred to as "concurrence.,,16 Concurrence is not the same as what Lehrer calls "coherence." Coherence is a relation that is defined in terms of the already-established reasonableness of accepting that p in the face of objections to that acceptance, and so it is a condition of justification rather than of reasonableness. 17 Concurrence and coherence are closely related in that both are based on the evaluation system. So the acceptance ofp may be invoked to answer an objection to the acceptance of q, and vice versa. It is open to foundationalists to incorporate mutual support into their systems. Chisholm allows that concurrence can add to the reasonableness of what is in itself reasonable to some extent. 18 He illustrates the role of concurrence using Meinong's analogy of cards tilted up against one another so as to provide mutual support.

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In general, for foundationalists there are some acceptances whose reasonableness can be accounted for, but which need no other acceptances to make them reasonable. They might be made reasonable by themselves or by some external factor. As it has been described thus far, Lehrer's account of concurrence is nonfoundationalist. There appears to be nothing in it that can confer any degree of "substance and rigidity" except for other acceptances. Lehrer, as is well-known, rejects foundationalist accounts of justification. One of his central antifoundationalist arguments helps to flesh out the ways in which acceptances support each other reciprocally. The justification of particular beliefs usually rests on an appeal to general beliefs, e.g., those concerning how successful one is in making judgments based on perceptual evidence (one's "track record"). Lehrer makes the case that such general beliefs are not basic but are justified by particular beliefs about individual cases of success, and vice versa, which involves "arguing in a circle" ([6], p. 93). This suggests, contrary to the foundation theory, that the justification of both kinds of statements may be reciprocal, that each justifies the other as the result of cohering with a system of beliefs containing particular beliefs about what we experience, as well as general beliefs about our competence to discern truth from error and the frequency of our success in so doing. To concede this, however, is to give up the foundation theory and embrace the coherence theory instead. ([6], pp. 93-4) This account of coherence in justification can be straightforwardly extrapolated to the way in which acceptances are made reasonable by other acceptances through concurrence. What makes it reasonable for an epistemic agent to accept that p is what he accepts about his competence and previous success, and it is reasonable for the agent to accept this general information about himself because of what he accepts about features of himself that make him competent and about individual instances of success. There is no independent source of reasonableness, nor is any acceptance reasonable in itself. This can be called a "broad concurrence" account of reasonableness. In the balance of the paper, it will be argued that this account is preferable to another account proposed by Lehrer, one which is very suggestive offoundationalism.

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TRUSTWORTHINESS

The reasonableness of acceptance is said by Lehrer to depend on acceptances about one's competence and record of success. It is convenient to say that in that case, reasonableness depends on acceptance of one's "trustworthiness." It is more difficult to say, however, what exactly trustworthiness is for Lehrer. At times, he seems to equate it with competence in accepting information successfully. An example is the acceptance that I see a zebra. In order to be justified, the acceptance must be reasonable to some extent. For it to be reasonable to accept, "I must have reason to think that I can tell a zebra when I see one in circumstances like those I am in at the moment, and consequently that I am trustworthy in such matters" ([ 6], p. 138). If! accept that I am competent in evaluating information that I have accepted, I can be said to accept that I am trustworthy in fulfilling the epistemic purpose in the present case. Note that one need not actually be successful in the present case, or even in a large number of cases, to qualify as being competent. So trustworthiness need not be a function of "my current rate of success in obtaining truth and avoiding error" ([6], p. 139). We may grant that someone is competent in fulfilling the epistemic goal but has run into a streak of bad luck. Even if competence does not require a successful track record, success does have a role to play in making acceptance reasonable. Specifically, it provides evidential support of the acceptance of one's competence. The claim that I am trustworthy in any particular matter under any special set of circumstances may be justified on the basis of the other things that I accept; I accept that I have had success in reaching the truth about similar matters in similar circumstances in the past and that the present circumstances do not differ in any relevant way from past circumstances when I was correct. ([6], p. 138) This approach might be generalized beyond particular cases to one's competence in acceptance overall. A generalized view of one's own competence seems to be what is codified in principle (1), which states in an unqualified way that I am trustworthy in what I accept. Lehrer claims that this principle must be accepted in order for any acceptance to be justified ([6], p. 138), and it plays a crucial role in conferring reasonableness. If one did not accept that one is trustworthy in general, then one would be unable to respond to an objection that casts doubt on competence in accepting in general. And since the acceptance system is the basis for responding to objections, its use would be indefensible. By extension, since the acceptance system also supports the reasonableness of acceptance, it would

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not be very reasonable to accept anything unless one accepted that one is trustworthy in what one accepts in general. On the interpretation of trustworthiness as competence, the principle means that in accepting what I do in general, I exercise competence in fulfilling the epistemic purpose of acceptance. In that case, the reasonableness of principle (T) would be supported by acceptances about one's overall record of one's success in everything one accepts. It is reasonable to accept that I am generally worthy of my own trust to the extent that I accept that I have earned that trust, so to speak. Lehrer has a second way of understanding trustworthiness: as a deontological notion, "an irreducible element of epistemic value" ([5], p. 138). He describes it as "a notion of what is worth accepting and what methods are worth using" ([5], p. 138). In his account of the normative dimension of trustworthiness, he divorces it entirely from considerations of actual competence and success. His purpose in so doing is to accommodate the intuition that it is reasonable to accept what one does even if one is the victim of massive deception. Though Lehrer does not make this point, it is clear that such an agent would then be completely incompetent, not merely unsuccessful, in fulfilling the epistemic purpose. Since, reasonableness requires acceptance of trustworthiness, Lehrer wants to say that a victim of deception may nonetheless be trustworthy. "I am worthy of my trust in what I accept though I am deceived. I am as trustworthy as the circumstances allow" ([6], p. 140). If worthiness of one's trust in acceptance does not require actual competence in fulfilling the epistemic purpose, what does it require? Lehrer casts himself in the role of a hypothetical demon-victim and describes himself as being deceived "through no fault of my own" ([6], p. 139). Being worthy of one's own trust, on this deontological construal, is a matter of having followed certain standards in searching for the truth. As Lehrer puts it regarding the demon case, "I seek to obtain truth and avoid error with the greatest intellectual integrity" ([6], p. 140). Similarly, one is trustworthy when one is "circumspect and seeks to detect every error" ([6], p. 192). Trustworthiness, viewed deontologically, is the result of the use of a general method of approaching acceptance, in the exercise of which one takes on objections forthrightly, meeting them when one can and changing one's view when one must. It also requires the willingness to change one's methods of getting at the truth if need be. In general, Lehrer says that his trustworthiness "rests on a dynamic process of evaluation and amalgamation of information I receive from others and from my own experience" ([6], p. 140). Lehrer's example of trustworthy but unreliable acceptance is described in a way that suggests that the agent has, in general, done her best to fulfill the epistemic purpose. But it is psychologically unrealistic to assume that there is a constant level of circumspection applied in every act of acceptance, so in general, one's acceptances will fall somewhat short of this standard. If

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acceptance is restricted to cases of taking information to be true in which one has done one's utmost to avoid error, then there is little, if anything, that people accept. We simply do not go through exercises like Descartes' Meditations in our ordinary lives. It would seem that trustworthiness in practice requires a lower standard of circumspection. Moreover, it would be extraordinary if anyone applied a single standard consistently. Given that this is the case, it is best to look at a range of degrees of circumspection, beginning with some point at which one is, so to speak, "circumspect enough" in trying to fulfill the epistemic purpose. To put it another way, one's methods for arriving at the truth are good enough as means to fulfill the epistemic purpose. Competence and methodological circumspection should be closely related in a plausible account of reasonableness. If an epistemic agent accepts that his methods for fulfilling the epistemic purpose are good enough, this seems to imply that he accepts that he is competent in accepting what he does. A method is not adequate for the fulfillment of a purpose unless it confers competence on the agent exercising it. If the virtue of the method is circumspection, then circumspection should not be divorced from competence. A good-enough method, then, is one which involves both the normative element of circumspection and the descriptive element of competence. To get a feel for why this is so, suppose the demon victim accepts that she has done her very best to fulfill the epistemic purpose. Should she, on that basis alone, accept that she is trustworthy? It would seem not, but rather that she should also accept that her most circumspect efforts are the sort of thing that will help her fulfill the epistemic goal: in short, she needs to accept that she is competent in accepting what she does. One must not isolate the acceptance of one's trustworthiness from one's other acceptances. 19 If trustworthiness requires competence as well as circumspection, we should concede, pace Lehrer, that the victim is not trustworthy but only falsely accepts that she is. This seems a superior way to handle the case, in that it accords more closely with our ordinary notion of trustworthiness. All Lehrer really needs to say is that the victim is epistemically blameless in a way that can allow her acceptance to be reasonable, if not justified. And this can be handled if it is allowed that she reasonably, albeit falsely, accepts that she is trustworthy in what she accepts. There is one further complication in understanding principle (1). The principle is simple enough on the surface, stating that I am trustworthy in what I accept to fulfill the epistemic purpose. But Lehrer considers it as "a statement ofa capacity and disposition to be trustworthy" ([6], p. 139). This qualification is due to the fact that one may fail to follow good-enough procedures in specific cases of acceptance, though one is generally disposed to follow them. In what follows, then, we shall take it that it is the disposition to be trustworthy that is supposed to account for the reasonableness of acceptance.

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How does it do so? Our original account of reasonableness was based on the "broad concurrence" approach, which regards the reasonableness of any acceptance to be a function of the reasonableness of all other acceptances. It can now be expanded to incorporate the elements that contribute to trustworthiness. A crucial class of acceptances in this regard is that of acceptances about our competence to accept all and only what is true in specific areas of investigation and in general. These acceptances about our competence are supported by acceptances about our success in fulfilling the epistemic purpose, and these in turn are supported by our particular acceptances. Another crucial class of acceptances is that of acceptances about our integrity and circumspection in accepting what we do in specific areas of investigation and in general. Such acceptances will be supported by observation of the way in which we go about accepting what we do, as well as acceptances about what constitutes the best means to fulfill the epistemic goal. Most importantly, they will be based on what we accept about the way we respond to objections and to new information. Principle (T) should be taken as summarizing these acceptances about many facets of the acceptance system. Trustworthiness helps to make other acceptances reasonable only because of its concurrence with many elements of the acceptance system. Lehrer does not, however, always describe the relation between principle (T) and reasonableness in terms of "broad concurrence." Instead, he relies mainly on what he calls the "trustworthiness argument" to make the connection in a way that appears to be more direct. This, it will be seen, leads Lehrer in the direction of foundationalism.

4.

THE TRUSTWORTHINESS ARGUMENT

The "trustworthiness argument" consists of two inferences. The first consists of two premises and a conclusion, and the second is a direct inference from the first conclusion. The first premise asserts my trustworthiness and the second my acceptance of some information as true. It runs verbatim as follows. 20

T. I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true. I accept that p with the objective of accepting that p just in case it is true. Therefore, I am trustworthy in accepting that p with the objective of accepting that p just in case it is true. Therefore, I am reasonable in accepting that p with the objective of accepting thatp just in case it is true. ([6], p. 139)

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Since there is no restriction on the value ofp, the conclusion must be taken to be generalizable to all acceptances. Lehrer notes that the first inference is meant not to be deductive, but rather inductive. That is, the first premise is not intended to be a universal generalization "to the effect that I am always trustworthy in what I accept" ([6], p. 139). Instead, it is supposed to be taken as a claim to the effect that I am generally trustworthy in what I accept.

It is like the inference from the premise that my lawyer is trustworthy to the conclusion that he is trustworthy in the way he has constructed my will or from the premise that a city water supply is trustworthy to the conclusion that the water supplied in my glass is trustworthy. ([6], p. 139) This is why he understands the principle of trustworthiness to be about a capacity or disposition. His lawyer may be disposed to act in a trustworthy way but fail to do so, perhaps due to weakness of will. Similarly, epistemic agents can be subject to "doxastic akrasia" ([6], p. 142). The second inference is an enthymeme. It depends on the conditional: if I am trustworthy in accepting that p with the objective of accepting that p just in case it is true, then I am reasonable in accepting that p with the objective of accepting that p just in case it is true. In [4], a variant of the implicit conditional is made explicit: "If I am reasonable to trust my acceptance of p, then I am reasonable to accept thatp" ([4], p. 7). Having elucidated the structure of the argument, we may now examine its premises. As already noted, the first premise is not to be taken as strictly universal, but only as a description of a "capacity and disposition to be trustworthy." In terms of the way Lehrer understands trustworthiness, to say that I am generally trustworthy is to say that in accepting what I accept, I generally, though perhaps not always, proceed according to good-enough methods. In the same way, a city's water supply might be generally trustworthy because its operators generally follow, well-enough, standard methods to keep the water safe, even though they may fail to follow those methods from time to time. The second premise, I accept that p, is ambiguous and could describe the act of accepting that p or the fact that p is already being accepted. The most plausible reading is that it describes what is already accepted. Otherwise, the argument would be limited in its scope to what is presently being accepted. Lehrer's goal in advancing the argument is clearly to provide support for the reasonableness of everything that a person has accepted. Moreover, the argument itself can apply only to what a person has already accepted, not to a person's act of accepting that p. If p has not yet been accepted, then the second premise is false.

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The premise might be taken as describing an act of acceptance because of a remark Lehrer makes in the second edition of Theory ofKnowledge, just after introducing principle (1) and before giving the "trustworthiness argument." If someone else accepts that I am trustworthy in this way, then my accepting something will be a reason for her to accept it. Similarly, if I accept that I am trustworthy in this way, then my accepting something will be a reason for my accepting it. ([6], p. 138) The most plausible construal of the description of the other person's acceptance of my trustworthiness is that she uses it, along with the fact that I accept some information, as a factor in evaluating that information and making a decision to accept it. But in that case, the analogy breaks down, since I cannot make what I already accept a factor in my deciding to accept it. My acceptance of my own trustworthiness can playa role in my deciding what to accept, in that without it, I might be disposed to withhold judgment rather than accept any information at all. It will be argued below that this generic way in which trustworthiness makes accepting reasonable is also the only way in which it makes what is already accepted reasonable. Given the interpretations ofthe two premises, the first conclusion must be read in this way: I have accepted that p on the basis of good-enough methods for obtaining truth and avoiding error in the acceptance of p. In the context of the trustworthiness argument, what those methods are is immaterial. Since I am trustworthy, the fact that I accept that p means that I have (most likely) relied on those methods I deem fit to make my acceptance a correct one. Now we can see how the first conclusion supports the second one: why trustworthiness entails reasonableness. It has been noted that Lehrer assumes that one can tell how reasonable it is to accept a given piece of information, relative to one's evaluation system. Presumably this means that one can determine how suitable its acceptance is to advance the epistemic purpose. Then the idea would be that if I use the methods I deem to be good enough for fulfilling the epistemic purpose in accepting that p, then I should regard the purpose as being fulfilled. Lehrer states the relation this way: "My trustworthiness serves the objectives of reason, and if I am trustworthy in the way I serve the objectives of reason in what I accept, then I am reasonable to accept what I do" ([5], p. 136). So the thrust of the whole argument is this. IfI am disposed generally to use good-enough methods in accepting what I do, and I accept some piece of information p, then I can conclude inductively that I have used good-enough methods in accepting that p. If I have used good-enough methods for accepting that p, then my acceptance that p is reasonable, to some degree. Ordinarily, when we evaluate the reasonableness of acceptance, we take into account the specific methods which are applicable to the specific

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information in question. The statement "I am reasonable in accepting that p" can be understood in two very different ways. It can be, and ordinarily is, read as a statement about the reasonableness of accepting the specific information p. Or it can be read as a statement about accepting any information at all, regardless of its specific content. It is only the latter sense that could possibly be established by the "trustworthiness argument." It is only in this sense that Lehrer could be entitled to assert that, "A consequence of adding principle (T) to my evaluation system is that I may reason from it and the acceptance of some target acceptance that p to the conclusion that the target acceptance is reasonable" ([6], p. 139). A more specific counterpart to the generic "trustworthiness argument" might be one to the effect that one is disposed to be circumspect one's investigations and that those methods of investigation sanction the acceptance of the specific information p, so that it is reasonable to make a commitment to the truth of p. One would expect that the first premise would be established inductively. The second premise would be established by appeal to the specific evidence in favor of accepting that p. The original "trustworthiness argument," on the other hand, says nothing about what makes it reasonable specifically to accept that p rather than some other information. So whatever degree of reasonableness it establishes is minimal compared to that established by the counterpart argument. Suppose an ordinary person were to ask me why it is reasonable for me to accept that the water in my glass is safe to drink. If I were to respond, "Because it is something that I accept, and I use good-enough methods to accept what I do," my response would most likely be met with bewilderment. On the other hand, if a foundationalist like Chisholm were to ask this question in the context of his epistemological investigations, the answer would make sense, since he then would be concerned with the source of reasonableness as such. The "trustworthiness argument" is really appropriate only in the context in which Lehrer raises it, i.e. as a response to a foundationalist objection. Justification depends on the reasonableness of what one accepts, and reasonableness depends on the acceptance of trustworthiness. "The foundationalist will surely note that everything now depends on the claim that my acceptance is a trustworthy guide to truth and that I am trustworthy, as I aver. She will inquire how that claim is itself justified" ([6], p. 138). The foundationalist inquiry can be extended to the issue of reasonableness: what makes it reasonable for me to accept that I am trustworthy? What gives that acceptance what Chisholm called "substance and rigidity?" Though appeal may be made to competence and success, the following response has to be given: "when I accept something, that is a good enough reason for thinking it to be true, so that it is reasonable for me to accept it" ([6], p. 138). Again, "If! accept that I am trustworthy in this way, then my accepting something will be a reason for me to accept it" ([6], p. 138).

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This generic approach has the advantage of being able to confer reasonableness in one fell swoop, rather than requiring that each acceptance be shown to be reasonable on its own. In that case, it looks as though Lehrer is making a concession to the foundationalist by not resting with the "broad concurrence" approach outlined above. That is, he is singling out one particular acceptance as supporting the reasonableness of all the others. Moreover, he holds that principle (1) makes itself reasonable, since it applies to itself if it is accepted. This is structurally akin to self-justifYing acceptances in a foundationalist theory of justification, where there is a narrow, rather than a broad, circularity. The self-application of principle (1) draws on the foundationalist model of self-justifYing acceptances, such as "I accept something," which exploits the self-referential character of what is accepted. 2 ! Lehrer acknowledges a measure of foundationalism in his account of justification: "To be personally justified one must accept some principle of trustworthiness that is in part self-justified" ([6], p. 202). This is on the grounds that, "Part, but not all, of what makes us personally justified in accepting that we are trustworthy is that we do accept that we are" ([6], p. 202). Reasonableness is treated in a parallel way, though not explicitly. The question that remains is whether this foundationalist turn is well motivated.

5.

THE REASONABLENESS OF THE PRINCIPLE OF TRUSTWORTHINESS

Lehrer offers two accounts of what makes principle (1) reasonable, both of which require that it contribute in some way to its own reasonableness. On one account, the contribution is indirect; on the other it is direct. The first account will not be plausible to someone who rejects all circularity in the relation of evidential support. The second account is burdened with its own variety of circularity and has additional problems of its own. In the first account, the claim that one is generally disposed to be trustworthy in acceptance is supported by an inductive generalization. The starting-point is the trustworthiness of most of one's specific acceptances and the conclusion is that one is generally disposed to be trustworthy in acceptance. What defense should [a person] offer in favor of (1) itself? She may, of course, appeal to the character of what she accepts, to the various things she accepts, and reason inductively from premises concerning the trustworthiness of individual acceptances in support of her conclusion that (1). She might reflect on what she has accepted and her fine track record of mostly accepting what was worthy of her trust to accept. This argument would establish that

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the trustworthiness of her acceptances manifests her disposition to be trustworthy in what she accepts. ([6], p. 142) The reasonableness of principle (7) in that case depends on the reasonableness of the acceptances that comprise the information invoked in the defense. For example, it must be reasonable, to some degree, for the person to accept in any given case that she has accepted what she has in a trustworthy way. What makes these acceptances reasonable to the degree they are will have to involve the acceptance of principle (7), as was noted above. Lehrer claims that it is the "trustworthiness argument" that connects (7) with the more specific acceptances. So the principle makes an indirect contribution to its own reasonableness, engendering a circle. There is obviously a circularity in the trustworthiness argument when we use the principle (7) as a premise to support the conclusion that other acceptances are reasonable and then use those acceptances and the principle itself to conclude that it is reasonable to accept it. ([6], p. 143) The circularity to which Lehrer refers is a version of "broad concurrence," with principle (7) playing a crucial role by conferring on everything one accepts the reasonableness it has. Lehrer recognizes that principle (7) cannot be used to defend its own reasonableness in the face of a skeptical objection. But to explain why it is reasonable to accept what we do, the circle may be virtuous. If we have a principle that explains why it is reasonable to accept what we do, it is a virtue rather than a vice that it should at the same time explain why it is reasonable to accept the principle itself. ([6], p. 143) The crucial difference between responding to a skeptical objection and giving an explanation is that in the latter case, the datum is taken for granted. So we assume that it is reasonable to accept principle (7) and ask why this is the case. Since it is not meant as a response to a skeptic, at most it shows to a person already committed to the reasonableness of what he accepts what it is that is supposed to make those acceptances reasonable. It does so by appeal to a notion of mutual support that many would find suspect. Perhaps the appeal to mutual support can be avoided if the reasonableness of principle (7) is explained by a direct application of (7) to itself. "If a person accepts (7), then her acceptance of (7) itself will have the result that it is reasonable for her to accept (7) by the application of the trustworthiness argument to (7) itself as the target acceptance (P)" ([6], p. 142). He takes this

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direct self-application to be "natural," apparently since (T) is applicable to all other acceptances ([6], pp. 142_3).22 But the direct self-application of (T) in the "trustworthiness argument" once more opens up the issue of circularity, where the circle is now as small as it can be. As Lehrer describes them, foundationalist theories of justification appeal to self-justifying acceptances. 23 These acceptances are said by the foundationalists to guarantee their own truth. The use of principle (T) to explain its own reasonableness appears to allow a similar sort of "bootstrapping" operation. But the circularity here is different, since the acceptance of one's trustworthiness does not in any way guarantee the truth of that acceptance in the way that the acceptance of one's existence guarantees that one exists. In his 1999 article "Knowledge, Scepticism and Coherence," Lehrer gives the following account of the explanatory role played by principle (T). I accept that I am trustworthy in what I accept, and if I am trustworthy in what I accept, then I am reasonable in accepting that I am trustworthy in what I accept. My trustworthiness in what I accept explains why I am reasonable in accepting that I am trustworthy in what I accept. ([5], p. 136) He opts for this small circle over the larger circle because it allows him to avoid a regress in explanation. "I could argue for my trustworthiness by consideration of other things I accept and my success in attaining truth, but that way a regress threatens, whatever the merits of such arguments in supporting the principle" ([5], p. 136). Butthere is no regress when the other things one accepts are made reasonable in part by the acceptance of one's trustworthiness, so we are not forced to apply the principle to itself to account for the reasonableness of acceptance. Whether the small circle actually explains anything remains to be seen. In the second edition of Theory ofKnowledge, published in 2000, Lehrer does not mention the regress argument, and as seen above, he explains the reasonableness of accepting (T) by appeal to its concurrence with the whole acceptance system. Still, though Lehrer does not defend the use of principle (T) to explain its own reasonableness without appeal to any other information, he does endorse the direct application of (T) to itself. What reason is there for doing this, except as a formal exercise? Lehrer notes that the argument is "more direct" than one using an inductive argument from individual cases of trustworthy acceptance ([6], p. 142). This directness has the advantage of economy, but it gains this advantage at the expense of content. It is useful to note that Lehrer recognizes that he is not making the stronger claim that principle (T) is completely self-justifying, though "the principle of our own trustworthiness contributes to its own personaljustification" ([6], p. 202). It does not justify itself fully because it "must cohere with what we

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accept about our successes and failures in past epistemic employment" ([6], p. 202). In that case, one must ask why Lehrer restricts this requirement to justification. Can we plausibly say that it is reasonable to accept a piece of information without regard to whether it coheres (or "concurs") with information we have about our past record of success, among other things? The fact that reasonableness (to some unspecified degree) need not meet the standard of justification does not exempt it from the need for a comprehensive base of support. This consideration raises the more general question of what kind of explanation could be provided by the direct self-application of principle (1). I want to know why it is reasonable for me to accept that I am trustworthy in what I accept. In terms of the interpretation of trustworthiness developed thus far, the question is why it is reasonable for me to accept that I have a disposition to use good-enough methods in accepting what I accept. The obvious indirect explanation for this is on the basis of what I accept about how I have used goodenough methods in the past. The indirect loop is generated by adding that part of what makes those acceptances reasonable is the acceptance of my own trustworthiness. The direct explanation is simply a vastly diminished version of the indirect explanation, one which omits all the details that enlighten me as to why it is reasonable to accept that I am trustworthy. The result is hardly edifYing. Suppose I were testifYing to a jury and averred that I am trustworthy in my testimony. When asked to explain why it is reasonable to accept that I am trustworthy, I answer that my original statement that I am a trustworthy witness is what explains why it is reasonable for me to accept that I am. Would I have explained, to anyone's satisfaction, anything at all? Another way to put the point is by noting what kind of reasonableness is supposed to be explained. As was noted above, we can ask, for any given piece of information (P), whether it is reasonable to accept that (P) as having a given content, or whether it is reasonable to accept that (P) in the sense that it is reasonable to accept what we accept in general. And as has been argued earlier, the kind of reasonableness established by the "trustworthiness argument" is generic. So when principle (1) is the target acceptance, the most the application of the trustworthiness argument to (1) can explain is that it is reasonable for me to accept that (1) insofar as it is reasonable for me to accept anything at all. So the direct self-application of principle (1) does nothing to explain why it is reasonable to accept information with the specific content that I am trustworthy in what I accept. Lehrer might respond to this description ofthe thinness of the explanation by claiming that any explanation is better than none. The principle itself is part of the account of the reasonableness of any acceptance, and so if it were not reasonable to accept principle (1), there would be no explanation at all. In that case, principle (1) "should be a kind of unexplained explainer that explains why

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it is reasonable for us to accept other things we accept and then falls mysteriously silent when asked why it is reasonable to accept the principle itself' ([6], pp. 143-4). Lehrer states that he seeks to maximize explanation and leave nothing unexplained ([5], p. 137). If (1) does not explain itself, then it is a "kind of explanatory surd" ([5], pp. 136-7). Preference for maximizing explanation and avoiding the surd is "one I act upon in developing my philosophy" ([5], p. 137). The surd can, however, be avoided with the broad account that explains specifically why it is reasonable to accept that I am trustworthy. It can also be said that this account provides a vastly more thorough explanation, and so it helps to maximize explanation. It explains something that would be left unexplained by the mere direct self-application of (1), namely, why my acceptance of the specific information that I am trustworthy is reasonable. As stated above, Lehrer's version of the broad account of reasonableness places principle (1) in the key role of explaining reasonableness on all acceptances. In view of the present discussion, it seems that this role is not as crucial as it first appeared. The principle can only explain the reasonableness of acceptances qua acceptances. The bulk, so to speak, of their reasonableness is explained by the specific concurring information that supports them. And as argued above, principle (1) itself is a summary of a complex of information about the methods one uses in fulfilling the epistemic purpose. All, or nearly all, of the reasonableness of accepting principle (1) itself stems from specific concurring information. So while it might be granted that (1) plays an important role in conferring reasonableness, that role is not foundational. A final consideration Lehrer advances in favor of the direct selfapplication of principle (1) is an appeal to analogies. The first of these is due to Reid: "just as light, in revealing the illuminated object, at the same time reveals itself, so the principle, in rendering the acceptance of other things reasonable, at the same time renders the acceptance of itself reasonable." ([6], p. 143). Notice that, in Reid's image, light "illuminates" other objects but "reveals" itself: it makes both other objects and itself visible. To make the analogy work, light would have to make itself visible in the same way that it makes the other objects visible. But it does not make itself visible by illuminating itself in the way it illuminates other objects. So this is not a good way of illustrating how the application of principle (1) explains its own trustworthiness. The second analogy is that of a keystone. The keystone is a triangular stone inserted in the top of an arch. It supports the arch, for the arch would collapse were it removed; at the same time, it is, of course, supported by the other stones in the arch. We may think of the stones in the arch as the acceptances in the acceptance system and the principle (1) as the keystone. ([6], p. 143)

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Lehrer might also have noted that the keystone would fall to the ground if the other stones were removed. The keystone supports itself only through its support of the other stones. A keystone is not a foundation stone. So this analogy, if it has any value at all, favors an account of the reasonableness of accepting the principle of trustworthiness in which the principle supports itself indirectly. In general, it favors the "broad concurrence" account of the reasonableness of acceptance. In summary, there seems to be nothing favoring the direct application of (T) to itself other than the fact that it can be made and that it simplifies the response to a skeptical objection to the reasonableness of what one accepts. But in fact it is no response to a skeptic, and if it explains anything at all, it explains only how it is reasonable to accept to some extent, merely as something that is accepted in general. Even this explanation is largely incomplete and can only be completed by appeal to a large number of other acceptances. Finally, there is no explanation of why the specific content of (7) is reasonable to accept. All of these deficiencies disappear when "broad concurrence" is invoked to explain what makes principle (T) reasonable to accept epistemically.24 So the direct self-application of (T) appears to be a useless exercise. It might even do some harm by engendering the illusion that the principle of trustworthiness is foundational rather than a "first among equals." Given the argument of this paper, Lehrer has no reason to make his "ecumenical" concession to foundationalism ([6], pp. 201-3).

6.

CONCLUSION

Lehrer's doctrine that reasonableness is based solely on acceptance leaves him open to a charge of broad circularity, a charge avoided by foundationalist accounts of reasonableness. It is only through a relation of mutual support that acceptances can make one another reasonable. Lehrer singles out a special acceptance, that I am trustworthy in what I accept, as playing a key role in providing that support. It has been argued here that acceptance of the principle makes the mere acceptance of a piece of information, including itself, reasonable to some extent, though in an entirely generic way. It does so in the context ofthe acceptance system as a whole. The principle of trustworthiness might also make itself reasonable by applying to itself directly, in which case it seems to be foundational and potentially to avoid the problem of broad circularity. But this direct application is narrowly circular and so holds no advantage in this respect over the indirect application. Because a direct application explains nothing that is not explained by the indirect approach, and indeed omits what ought to be included in any explanation of reasonableness, there is no reason to concede anything to the foundationalist. The essential ingredients in the explanation of reasonableness

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are to be found in the acceptance system as a whole, as is consonant with Lehrer's coherence approach to justification. The narrowly circular application of the principle of trustworthiness to itself is an aberration.* *1 am grateful to Lenny Clapp for several excellent suggestions for improving the presentation in this paper.

ENDNOTES 1 This seems to be what Lehrer calls mere belief. which "arise[s] in us naturally without our bidding and often against our will" ([6], p. 40). 2 Lehrer acknowledges in his "bear print" example that sometimes circumstances dictate a greater degree of scrutiny than in normal circumstances ([6], p. 73). Complex or highly general information would also call for reflection. ] Ifreflection is not involved, there is no "decision" strictly speaking, but a commitment must be made in a manner analogous to the making of a decision. 4 This kind of comparison was made by Chisholm in [1]. 5 It would be fortuitous from the point of view ofthe agent. There might be some sort of external factor that makes the correctness of the decision non-accidental, as in the case of a device implanted in the brain that brings about correct acceptances. See [6], p. 186-8. 6 See [2], pp. 192-197. 7 Objections must either be "answered" or "neutralized" ([6], pp. 134-136). 8 Objective justification is described in Chapter 7 of [6]. 9 The "justification game" illustrates the way in which critical objections might be handled ifthey were to arise. See [6], pp. 132-128. ]0 This feature of acceptance is highlighted by theories of prima facie justification. 11 Presumably, one would be able to tell as well whether it is more reasonable to accept than to withhold acceptance. 12 This is less evident with respect to informativeness than with respect to probability, but very general information can be completely uninformative to a person who does not have the conceptual resources to integrate it into his view of the world. 13 The other components are the "preference system" and the "reasoning system." See [6], pp. 126-127. In [5], Lehrer notes that only the acceptance system is relevant to the issues that he raises there, and these are the issues discussed in the present paper. See p. 138, note 2. 14 It appears to be psychologically unrealistic to assume that an epistemic agent can properly distinguish between what he already believes and what he has already accepted. One reason is that we often forget how we came to take a given piece of information to be true. 15 The information contained in the acceptance system is also the basis for the determination of justification. 16 This term is taken from Chisholm, who attributes the concept to the ancient academic skeptic Carneades ([1], p. 43). 17 It may be that in many, most, or all cases, concurrence involves dealing with objections, in which case it is closely related to justification. 18 See [1], Chapter 3. 19 Since following good-enough methods requires evaluation of our own competence, we will hereinafter describe trustworthiness in terms of methods only. 20 Similar versions appear in [4], pp. 6-7 (called "the acceptance argument" there) and [5], p. 136.

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Lehrer allows that it is plausible that "I believe something" is a self-justified belief. See [6], p. 54. See also p. 67-8, where he writes that "fallibility infects almost all our beliefs" (emphasis added). 22 In the first edition of Theory of Knowledge, Lehrer had called the self-application of (T) "more natural" than trying to avoid the self-application for fear of self-referential paradox (p. 123). 23 See [6], Chapter 3. 24 This is not to say that these advantages make "broad concurrence" a convincing alternative to foundationalism. 21

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REFERENCES Roderick Chisholm. Theory o/Knowledge. Prentice Hall, 1966. Keith Lehrer. Knowledge. Oxford University Press, 1974. Keith Lehrer. A Theory 0/ Knowledge. Westview Press, first edition, 1990. Keith Lehrer. Self Trust: A Study o/Reason, Knowledge and Autonomy. Oxford University Press. Keith Lehrer. Knowledge, scepticism, and coherence. Philosophical Perspectives, 13: 131-139, 1999. Keith Lehrer. Theory o/Knowledge. Westview Press, 2000.

Chapter 12 THE DIALECTICAL ILLUSION OF A VICIOUS BOOTSTRAP* Richard N. Manning Carleton University

We can take it as given that at least one ineliminable goal of epistemic justification is the acquisition of true beliefs. From this it follows that no account of justification which fails to show that justification, as conceived in that account, conduces to truth, can properly be termed epistemic. Call this issue arising from the basic idea of what epistemic practice is all about 'the truth conduciveness problem'. In this paper I will discuss Keith Lehrer's approach to the truth conduciveness problem, in the context of his coherence theory of knowledge as undefeated justification. Lehrer's coherentist approach centrally involves an appeal to our own self-trust, which self-trust is itself purportedly warranted in part by appeal to itself. I will, in due course, argue that Lehrer's attempt to solve the truth conduciveness problem by appeal in this way to selftrust fails, leading to logical circles, abysses and blind alleys. But this failure is highly instructive. Self-trust is indeed crucial, not just to coherentist epistemology, but to epistemic practice as such. For this reason, self-trust I will suggest, neither can or need be argued for at all. Lehrer's strategy fails, then, not by placing too much reliance on self-trust, but by seeing self-trust as a candidate for justification. The truth conduciveness problem is, in its most general form, a problem for all theories of epistemic justification. The structural strategy for solving this problem invoked by foundational accounts of justification, in both their traditional and externalist forms, is clear enough: a claim is justified via a chain of epistemically acceptable inferential relations ultimately terminating in some claim or claims with a privileged epistemic status. Such claims, in virtue of their content or relations to the world, are prima facie likely to be true, and hence do 195

E.l. Olsson (ed.), The Epistemology of Keith Lehrer, 195-216. © 2003 Kluwer Academic Publishers.

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not require justificatory support from other claims. That is, according to foundationalism, there are basic claims which are non-inferentially justified. To suppose that there are such non-inferentially justified claims is not, of course, to suppose that agents do or even could have some good reasons for believing of any particular claim, or any class of claims, that it is so justified. Indeed, the foundational status of a belief means that no such belief could owe its justificatory status to anything the agent possesses as a reason. To suppose otherwise would reinstate the impotent regress of justification that foundationalism is in part designed to avoid. On the foundationalist picture, then, not every belief that isjustified need be justified by an agent's reasons. As William Alston notes, all that is needed to stop the regress of justification is belief which is immediately justified, whether or not the agent has reason to believe that it is so justified. l Faced with the natural objection that this would mean that ajustificatory chain could terminate in a claim which the agent has no reason to hold true, that from the agent's point of view this claim would amount to a brute assumption, Alston argues that there is no bar to adding the additional requirement that the agent have a justification for supposing the foundational claim immediately justified, but that this justification need not (and cannot) itself be immediate, but must be inferential. As it is a reason for holding the putative basic claim justified, it is moreover an epistemic reason in the sense of being a second order claim about the justificatory status of a first order claim. (More generally, a claim of order n about the justificatory status of some claim or claims oflevels ml, m2, ... mi
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that can justify a belief are further beliefs? As we have seen, coherence accounts of justification do not number among their virtues a logical structure obviously suited to the solution of the epistemic regress, and hence the truth conduciveness problem. Moreover, given the fourth condition, which holds that belief-belief relations are exhaustive of justificatory relations, the truth conduciveness problem has an immediate intuitive grip. Truth, after all, is a relation (or so we tend to think) between beliefs, among other things, and the world, not between beliefs and other beliefs. And why should we suppose that the first kind of relation is guaranteed on the basis of the second, on any particular account ofthe belief-belief relations that comprise coherence? Absent a good answer to this question, it is hard to see how belief-belief relations, so conceived, can be epistemic at all. So, despite the considerable intuitive appeal of the notions that it is the business of rationality to seek reasons for all claims, and to seek the kind of systematicity, unity, comprehensiveness, and explanatory power implied in the notion of coherence, coherence accounts of justification have continually foundered against the truth conduciveness problem. We can see this from the fact that the other main objections usually raised against coherence accounts are such that a solution to the truth conduciveness problem would go a long way toward mooting their force. Consider, for example, the objection that a fully coherent system of claims (including what seem to be empirical claims) might be utterly cut off from the reality it purports to capture; it is hard to see how this so called 'isolation objection' could get a grip, if it were satisfactorily demonstrated that the contents of such a system are likely to be true. Surely the demand for a connection between world and system is motivated by the sense that, absent such a connection, the system's contents could not be true of the world. So a demonstration of truth conduciveness, whether it invokes such a connection or not, disarms the threat that motivates the objection. Consider also the objection that there might be many possible coherent systems, but only one world for them to be about, or only one true such system. An adequate solution to the truth conduciveness problem would moot this objection too, either by showing that only one such system is possible, if truth is univocal, or by showing that truth is not univocal, if many equally coherent systems can be constructed by truth conducive means? The task for any coherentism, then, is to show that beliefs which cohere with one another in some specified sense are likely to be true, in a way that makes one whose beliefs are coherent in that sense epistemically justified in her beliefs. To understand the approach Lehrer takes to this task, it will help to contrast it with alternative coherentist approaches to the same difficulty. Coherence would obviously conduce to truth if truth were identified with coherence. But, as Laurence Bonjour points out, the truth conduciveness of justification on a particular conception cannot count in its favor as compared with other such conceptions, if our view of truth has been tailored, ad hoc, to

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guarantee that result. The same move would be open to proponents of any view of the nature ofjustification, and cannot help us to decide between them. Given this constraint, Bonjour despairs of the kind of demonstration of truth conduciveness I discuss here, one made from entirely from within the coherent system. His own approach to the problem is to attempt an a priori demonstration that coherent systems of belief meeting specific conditions are more probably true than false. This approach cannot work in the context of a pure coherentism, since it depends upon recourse to a priori judgments of comparative probability which are not themselves justified on coherence grounds. Bonjour recognizes this and consequently presents a coherence theory of empirical knowledge only.4 But perhaps it is possible, after all, to find an independent, non-trivial basis for identifying truth with coherence. This was the route taken by the classical coherentists, on whose view reality is a unified whole and claimsbeliefs contents or propositions-are abstracted parts of that whole which necessarily capture it in a merely partial way. The more comprehensive and coherent a set of such abstacta is, on such a view, the more closely it captures concrete reality itself, since the unification of comprehensive abstracta through coherence is just the reverse of the process of abstraction itself. Such views are out of favor in this predominantly atomistic age. Be that as it may, the general program of attempting to provide non-trivial grounds for identifying truth and coherence is still live. In his A System of Pragmatic Idealism S, Nicholas Rescher offers such an argument. Truth conceived as adequation to fact, is, according to Rescher, identifiable with the notion of optimal coherence with a perfected data base, where a data base is conceived as a set of candidates for truth. Whatever else may be said about this argument 6 , the highly idealized character of the conditions under which it concludes that coherence yields truth stand out. There is no pretending that we now have belief systems which are optimally coherent in Rescher's sense, and we are of course never presented with a perfected data base. Ironically, Rescher's approach is on this score similar to Bonjour's own effort to show that the stable coherence of empirical belief systems meeting certain requirements is in the very long run destined to yield truth. Whether or not idealization of this kind is appropriate in this context, Lehrer's approach makes no such appeals to the ideal, intending instead to show that concrete agents have a reason to think their current, certainly less than comprehensive, beliefs nonetheless I ikely to be true in virtue oftheir coherence, again less than ideal, with one another. One way to attempt to show that an agent's coherent beliefs are likely to be true under the normal, less than ideal conditions with which we situated humans are faced is to approach the matter through an analysis of meaning. On such a view, the truth of belief is built in through the relations with the world in virtue of which the very content of belief is fixed. The approach at which I am hinting is Davidson's. It invokes its own idealizations, thought in an entirely

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different spirit, and is not without its difficulties, which I will not pursue here. 7 Lehrer's approach, however, declines to see epistemology in the mirror of meaning, taking the contents of belief to be fixed, apparently, independently of any relations to the world which would ensure their likely truth. The contents of belief are what they are; the truth of belief is another, independent matter. If strictly all of the beliefs in a given system must be justified on the basis of coherence, and if the external connections that fix the contents of belief are put out of play in addressing questions of epistemic warrant, then there is nothing left to do but to seek the reasons for supposing coherence truth conducive in the contents of the members of the belief system themselves. We are left with the hope that beliefs about the probable truth of our beliefs can themselves be justified by their coherence with the very beliefs whose probable truth they assert. As our reasons will have to be reasons for holding a belief justified, they will be epistemic in the sense mentioned above, higher-order beliefs about the justificatory status of lower-order beliefs. We are to pick ourselves up to truth by our own epistemic bootstraps. Such is Lehrer's approach. For Lehrer, knowledge is undefeated justification, where justification is defined in terms of coherence with a background system. Lehrer offers the following definition: DK: S knows that p at t if and only if (i) S accepts that p at t, (ii) it is true that p, (iii) S is personally justified in accepting that p at t, and (iv) S is justified in accepting that p at t in a way that is undefeated. 8 Acceptance, for Lehrer "is a sort of positive attitude toward a content, resulting in employment of the content as background information in thought and inference."9 Acceptance is thus epistemically oriented belief, individuated functionally. Condition (iii) is concerned with the general structure ofjustification and the conditions under which a person is personally-subjectively- justified in accepting some content. For Lehrer, justification is coherence with a background system of acceptances. A subject S's acceptance system is the set of all statements of the form "S accepts that ... ," attributing to S just those contents S accepts in Lehrer's sense. S's acceptance that p is justified if and only if p coheres with her acceptance system. Lehrer takes the notion of comparative reasonableness as a fundamental primitive. A content coheres with an acceptance system if it is comparatively more reasonable for a subject to accept that content than to accept any competing claims, relative to that acceptance system. A claim c competes with a content p just in case it is more reasonable for S to accept that p on the

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assumption that c is false than on the assumption that c is true. That content p coheres with S's acceptance system if it beats or neutralizes all competitors. p beats c if it is more reasonable for S to accept p than c on the basis of S's acceptance system. c is neutralized for S if there is some n such that the conjunction (c&n) is as reasonable to accept on the basis of S's system as c itself, and (c&n) does not compete with p. Consider the following abstract illustration. Suppose a subject S avers some content q. An interlocutor, call him D, contests this claim, saying "not-q". Obviously it is more reasonable for S to accept that q on the assumption that this counterclaim is false than on the assumption that it is true. Thus, D's claim competes with S's. Is S justified in his averral? This depends on whether the counterclaim is beaten or neutralized on S's acceptance system. Suppose S's acceptance system also contains the following: "S accepts that r", and: "S accepts that r implies q". It is tempting to conclude that since D's claim that not-q is logically inconsistent with the entailments of these contents of S's acceptances, S's claim beats D's and is justified. But this would be premature. Nothing present in S's acceptance system bears on the reasonableness of accepting q over its competitor not-q. To see that this is so, simply note that the members of S' s acceptance system are not the contents accepted by S but rather statements of the form "S accepts that .. " And it is relative to members of S' s acceptance system rather than to contents accepted by S that competitors must be beaten or neutralized. Indeed, this point is important for Lehrer. If competitors had to be beaten relative to the contents accepted by S, rather than to the members of the acceptance system of S, then accepted contents would trivially beat competitors. For it is always more reasonable to accept some p on the basis of p than it is to accept some competitor to p (e.g., not-p) on the basis of p. Moreover, it is precisely the presence of the acceptance operator that distinguishes the relata of the coherence relation as doxastic contents, as opposed to, say, facts or propositional contents not believed; it is what makes Lehrer's coherentism doxastic.'o Now the members of S's acceptance system so described, "S accepts that r" and "S accepts that r implies q", bear no inferential or other rational relation to either q or not-q. How, then, is D's competitor to be beaten relative to S's acceptance system? Acceptance has the goal of obtaining truth and avoiding error. Hence the presence of"S accepts that q" in S's system makes it less reasonable for S to accept that not-q only if S' s acceptance of those contents is a reason for him to suppose them more likely true than not. That S accepts some contents, without more, is not a reason for him to suppose them true. Thus subjective justification is, to this point, unable to get off the ground. Before completing Lehrer's account of how justification might get airborne, let us first briefly turn to his fourth condition. This condition, which requires that a person's justification be "undefeated", is designed to help avoid

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counter-examples of Gettier and related sorts. Simplifying slightly, a justification is undefeated, for Lehrer, if it is undefeated relative to every set of acceptances that can be created by correcting errors in the agent's actual acceptance system. This ensures both that no essential falsehood is involved in the agent's justification, and that the claim at issue is true, since if it were not, the true claim that it is not would replace the false claim that it is true on some corrected version ofS's acceptance system, on which S 's justification would be defeated. Hence an undefeated justification of a claim is clearly epistemic. But whether an agent's justification is undefeated is simply not something which can be seen or determined from the doxastic point of view, here from within the agent's acceptance system. I I The agent holds all of her accepted contents to be true. Hence, from the doxastic point of view, there is no saying whether ajustification is merely personally justified, or in fact ultimately undefeated (hence not flawed) and yielding truth. The facts that make for veridical justification are, as it stands, unreflected in subjective justification. So to this point we have two problems. First, justification cannot get started. Second, the facts that show that justification is not defeated, hence is likely to yield truth, are not reflected in the agent's acceptances. Lehrer's bootstrapping strategy seeks to solve both problems at once. According to Lehrer, what is required to get justification started, and moreover to give an agent reason to suppose her justifications ultimately undefeated, is a kind of doxastic ascent. "One must have some information that such acceptance is a trustworthy guide to truth.,,12 "1 must accept ... that when 1 accept something, that is good enough reason for thinking it to be true, so that it is at least as reasonable for me to accept it than to accept its denial.,,13 Lehrer regards an inquirer's self-trust in pursuit of truth as a special principle of an acceptance system: T.

I am a trustworthy evaluator ofthe truth.

According to Lehrer, when a person accepts a principle such as T-when she accepts that she is trustworthy in the evaluation of truth-the crucial link between acceptance and epistemics, likely truth, is established. On his view, if S accepts Principle T, she can conclude not just that D's claim that not-q conflicts with her own views, but that it conflicts with what is likely to be true. Since it is more reasonable to accept what is likely to be true than what conflicts with what is likely to be true, S's claim that q would defeat D's competing claim. Thus, S' s claim would be justified. Principle T purports to make accepting something itself a basis for supposing it likely to be true. Moreover, since justifications that are defeated are not trustworthy, accepting that one's acceptances are trustworthy amounts to accepting that one's justification for a claim is not defeated. 14 One's personal

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acceptance ofT is supposed, then, to give one a reason for supposing that one's warrant is veridical as well as personal, and thus personal warrant is to be made epistemic. So if Lehrer's principle T works at all, it bootstraps acceptance to likely truth, turning coherence with what is accepted into epistemic warrant. But does it work? Recall that an acceptance system is comprised of statements of the form "S accepts that p." Lehrer calls Principle T a principle of detachment: he holds that one who accepts T is thereby entitled to detach the contents of her acceptances from the fact that she accepts them. This in turn permits those contents themselves to justify one another and to beat competitors in appropriate cases. But this detachment process fails, as the following argument shows. Let x, y, ... be variables ranging over propositional contents P, Q, R, .. . Introduce operators "As", such that "AsP" means "S accepts that P," and "reass", such that "reassP" means "S's acceptance that P is reasonable." Let P be some arbitrary content accepted by S.

(1)

AsP

Assume that S accepts Principle T: (2)

AsT

We may render T formally as T:

(X)(Asx -7 reassx).

Assuming that the acceptance operator does not create an opaque context 15, then (3)

As(x)(Asx -7 reassx).

It is tempting at this point to instantiate the universally quantified statement within S's acceptance in (3) with the content accepted in (1). But (3) is not a universally quantified statement; it is rather an acceptance, just like (1). In fact, no acceptance-no statement of the form "s accepts that ... "-follows logically from any other. Clearly, if the detachment process is ever to get started, we must introduce some logical apparatus that permits the desired instantiation. Moreover, the need for a logic of acceptance is not limited to detachment. Without a logic of acceptance, individual acceptances are isolated entities, bearing no rational relations, coherent or otherwise, at all (save bare consistency) to other acceptances. For coherence relations to be effective within an acceptance system, a fairly powerful logical apparatus will be required. Let us introduce the following three schemata.

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Asx ~ AsAsx; i.e. acceptance is iterative. (Asx & Asy) ~ As(x & y); i.e. acceptance is closed under conjunction. (Asx & x 1- y) ~ Asy; i.e. acceptance is closed under deductive entailment.

mai

6 employ in Think of these as inference rules a given subject maneuvering around her acceptance system. Since coherence is a matter of explanatory and inductive relations as well as deductive ones, the foregoing, though necessary, are not sufficient logical principles for Lehrer's theory. They do nonetheless permit the agent, despite the presence of the acceptance operator on each member of the acceptance system, to exploit some of the relations among the contents of her acceptances, e.g., by generating new acceptances by inference from others. But the question is whether this will help to detach any contents from the acceptance operator. We may proceed.

(4) (5) (6)

AsAsP As[(x)(Asx ~ reassx) & AsP] As[(AsP ~ reassP) & AsP]

(I), (a) (3), (4), (b) (5), (c)UI

We can now detach the consequent ofthe instantiated Principle T. (7)

AsreassP

(6), (c), MP

(7) says that S accepts that his acceptance ofP is reliable. But this is not what S needs. That S accepts that P is reliable is not sufficient to show that his acceptance of P is reliable. Even with the strong logical apparatus we have supplied, acceptance of Principle T has failed to help detach P from its acceptance operator. Thus P is no more reasonable to accept than its denial relative to S' s acceptance system. As Davis and Bender put it, information about what S accepts is not "adequate to drive the engine of justification." 17 What is required is access to the content p itself. Clearly, if T itself appeared in the acceptance system of S, then the necessary detachment would be possible. But T does not appear; the acceptance of T appears, and this acceptance is as impotent to detach itself as it is to detach other contents: (8) (9) (10) (11)

AsAsT As[(x)(Asx ~ reassx) & AsT] As[(AsT ~ reassT) & AsT] AsreassT

(2),( a) (3), (8), (b) (9), (c), UI (10), (c), MP

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That is, S accepts his acceptance of Principle T is reasonable. This, again, is no help. In order to break this cycle of acceptances, S needs recourse to Principle T itself.

(12)

(x)(Asx -7 reassx)

Assumption

Instantiating with any content, say P, we get:

(13)

AsP -7 reassP

(12),UI.

And then given (1), we get:

(14)

reassP

(1), (13), MP.

That is, S' s acceptance of P is reasonable. This of course applies to the accepted content T as well. (15) (16)

As T -7 reass T reassT

(12), UI (2), (15), MP

That is, S' s acceptance ofT is reasonable. But a glance at (12) shows that it is not of the form "S accepts that P" and thus cannot be a member of S' s acceptance system. The engine has no spark. The foregoing objection may appear overly technical, relying as it does on the precise definition of the acceptance system. This reply is inapt, for the exclusive use of doxastic states qua doxastic states in justification is of the essence for coherentism, and on Lehrer's view, it is the presence of the acceptance operator which marks a content as a member of an agent's acceptance system. Moreover, as we saw, justification for accepted contents would be trivial matter but for the presence ofthat operator. Be that as it may, it is clear that if justification is ever to get started, Lehrer needs some ground for including (12) or Principle T itself in S's acceptance system, free of any acceptance operator. Though Lehrer does not recognize that T is impotent as a principle of detachment, and thus does not directly address whether it could appear in an acceptance system without the acceptance operator, he does emphasize that T is a "special," "make or break" principle. Perhaps what he says in this context may show that T merits this special status. What are we to say with respect to T itself? Am I intrinsically justified in accepting T? Does the attempt to justify T take us to

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an even higher level of doxastic ascent generating a regress? Or does the attempt to justify T lead us in a short circle in which T provides us with the reason for accepting itself? There is a sense in which the answer to all three ofthese questions is positive,'S Now obviously, if Lehrer is serious that T is justified as a foundation-one acceptance among others but not in need of justification by appeal to the rest-he has just given up on coherentism itself, at least in any pure form.19 Nonetheless, it is interesting to note that T itself is not a particularly good candidate for foundational status. Perceptual, introspective and memory foundationalisms are preferable to a foundational ism of general trustworthiness for the simple reason that they discriminate between those sorts of beliefs that are highly trustworthy and those that are not. 1fT helps to justify anything one believes, it helps to justify everything one believes injust the same way. But we are of course much better at truly perceiving tables than at truly theorizing about quarks. It is absurd to suggest that common perceptual beliefs and speculative scientific claims are primafacie equally trustworthy in virtue of their mere acceptance. (That T would apply indiscriminately to all acceptances is a clue to the special status T has, I think, and is a point to which I will return.) Lehrer has two reasons for thinking T a good candidate for foundational status. First, T can be confirmed. That is, the more one learns about the world, the more support she has for believing she is trustworthy. This point can hardly count in T's favor as a foundation, for if it is a foundation it needs no further support, and if it needs confirmation it cannot, on pain of circularity, provide ground for that which confirms it. Furthermore, Principle T is by no means special among foundations in its confirmability. Our perceptual beliefs, introspective beliefs and memories are regularly confirmed by more ofthe same and by other beliefs as well. T gains no advantage over such foundations here. Second, Lehrer claims that principle T is preferable to other foundations because it "tells me my accepting something is a guide to truth." In particular, its content "provides reason for considering acceptance of it to be justified.,,20 That is, it indicates why it is itself a good foundation. But if T is a foundation, then it needs no extra support, from itself or elsewhere, as a foundation. If it is a foundation, then it can groundjustification. If it is not, then it cannot on its own ground its own justification or that of anything else. How is the justification of Principle T regressive? Any attempt to justify Principle T by reference to other acceptances depends upon the trustworthiness of those acceptances, and thus ultimately upon T itself. In addition to a circularity problem, to which I will turn presently, we face then, a case in which Principle T is applied to itself. Such self-reference is notoriously problematic, and the way to avoid it is also a way to avoid circularity. All we need do is ascend another level on our doxastic staircase, positing a meta-acceptance to the

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effect that one is a trustworthy evaluator of whether one is a trustworthy evaluator of truth. On pain of the same circularity and self-reference in the metalevel that we seek to avoid at ground level, the justification of the metaacceptance demands yet another T -like principle at yet a higher meta-level. And the regress ensues. Lehrer claims that this regress is not vicious. "The regress does not commit us to carrying out an infinite series of acts. On the contrary, it simply shows us that an infinite series ofT principles at various levels are each such that, when accepted, one is justified in accepting them all."21 Now, the mere fact that a regress is not vicious in the sense of requiring an impossible infinity of distinct acts hardly shows that the regress can actually confer justification. The idea here is that each Principle T in the series is justified by the one at the higher level, and that when one accepts the series as a whole, each member of it is justified. But the intelligibility of such an infinite series of metaacceptances is doubtful. Are we really to suppose that we understand, and can employ in reasoning, acceptances of the form AsTn, where Tn is to be unpacked as "I am a trustworthy evaluator of the truth of T n-l ", and where Tn-l is in turn to be unpacked as "I am a trustworthy evaluator of the truth Tn-2", for arbitrarily large, let alone infinite, n? I think the need to suppose so should call into questions the very project of attempting to justifying according T a special status as an acceptance among others. And even supposing we could make sense of this regressive justification we would still face the question "what justifies acceptance of the series?" Itself? That is self-referential and circular. Another meta-acceptance, of a yet higher order altogether? Another series of metaacceptances? We're off to the races again. We come finally to the circular justification of Principle T. The argument is supposed to run as follows: I accept that T; according to T my acceptances are trustworthy; therefore my acceptance ofT is trustworthy. But ajustification of T is supposed to tell us that it is reasonable to accept T in the first place, and in order to determine this we must put T out of play in our justification, just as we refuse to allow any claim we accept to figure in our justification for it when we are challenged, at least insofar as the claim is used directly to support itself. But while Lehrer remarks at one point that "even in the case of principle (T), we require some background information in order to be personally justified in accepting the principle,,22, this does not mitigate against the charge that the circle here is vicious. Clearly, any background information upon which the justification for T depends will itself depend vitally upon T for its own justification. Not only must T itself appear in its own justification, it must appear in the justification of everything else that appears in that justification. A less benign circle is hard to imagine. Moreover, as a functional matter-and remember that acceptance is a functional matter-reasonable people accept something that would appear to bar, or at a minimum conflict with, this circular justification: we generally

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accept that such circular justifications do not increase the antecedent likelihood or reasonableness of the justificandum. This conflict might be resolved by recourse to the idea that this specific acceptance is a competitor to the claim that T justifies itself, and that this competitor can be neutralized by being conjoined with the claim that this case of circular justification is benign. That is, while c: It is unreasonable to accept circular justifications competes with TR: My acceptance of T makes it reasonable for me to accept T, c&n: Circular justifications are generally unreasonable, and TR does not. But in order for c&n to neutralize c it must be as reasonable to accept c&n as it is to accept c itself. But an acceptance can only be reasonable if the content is more probable than its denial, relative to the acceptance system. This is precisely what circular justification, generally and in the case of Principle T, cannot show. Since the general prohibition on viciously circular justification clearly serves the interest in obtaining truth and avoiding error, c&n can work to neutralize conly ifTR is treated as an exception to the general prohibition on circular reasoning. But to grant an acceptance such an exemption seems utterly ad hoc. Now it is clear that, as a functional matter, we do trust ourselves as evaluators oftruth. But that is not to say that we in fact exempt the acceptance of our reliability from the standard proscription against circular justification. It would only follow that we exempt self-trust from this proscription if we appealed to self-trust as another acceptance exploited in an inference or argument for its own validity; and this is exactly what this neutralization involves. If that is how T achieved its special status, it would be at the cost of making us ad hoc, bad reasoners. But, as we shall see, general self-trust need not be conceived as an acceptance exploited in justificatory inference. Since Principle T is not justified as a foundation, and the regressive and circular justifications are unacceptably vicious, there is no reasonable ground for permitting Principle T to appear in one's acceptance system free of the acceptance operator. Consequently, the principle cannot operate as it must on Lehrer's account if we are ever to be justified in our acceptances. That we think we are trustworthy does not make what we think worthy of trust. Consequently, Lehrer's coherentist solution to truth conduciveness problem fails. Including an epistemic bootstrap among the relata of the coherence relation does not render that relation epistemic. In Self Trust, a comparatively recent work, Lehrer seems more aware of the futility of a bootstrapping demonstration of the reasonableness of our

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coherent acceptances. Conceding that "circular reasoning justifies nothing,m, Lehrer recasts his goal in appealing to self-trust as explanatory, rather than justificatory. He declares: "my intention is not to prove conclusions by circular reasoning, but to explain the reasonableness of what we accept ... in terms of a principle of our own trustworthiness." 24 The idea now is that, while the principle of self-trust cannot be used to prove that we are justified in accepting the principle, the truth of the principle can explain our reasonableness. But it remains the case that the explanatory strategy appeals to the truth of the principle of self-trust in order to explain the reasonableness of accepting that very same principle. So, as Lehrer concedes, the circularity has not gone away. But he argues that circularity is not impermissible in explanation. He claims that explanation, at least insofar as finite, must either end in some unexplained explainer, or in some principle which explains both itself and other explananda. Thus, "we must choose between the surd and the loop". 25 Seeing no reason to prefer explanations that terminate in surds, he opts for to admit circular explanations (though he is not dogmatic about this-we may opt for the surd if we like), on the ground that, if we do so, "nothing need be left unexplained,,26. This putative retreat from justification to explanation cannot cure the logical ills of the appeal to self-trust. First, in explanation, as oppose to justification, the truth of the explanandum is taken for granted. Here, at least part of the explanandum is the justified status - the reasonableness -- of acceptances. Thus the reasonableness of what we in fact accept is taken for granted in this explanatory project. But in taking this for granted, Lehrer has certainly changed the game we have been playing. If we were willing to take this reasonableness for granted all along, then the truth conduciveness of our acceptance generating processes would not, it seems, have merited such fuss. Indeed, one wonders why a natural, psychologistic description of our acceptance formation processes would not have sufficed to describe that whose reasonableness needs to be explained (but not proven). Now Lehrer might respond that there could be no explanation of the reasonableness of our belief forming processes described psycho logistically. After all, it is reasonableness we are trying to explain, and, given Lehrer's staunch anti-naturalism 27 , there can be nothing reasonable about a merely natural psychological process. But this shows, I think, that the distinction between explanation and justification here is not so sharp as Lehrer must suppose. For surely the reason there can be nothing reasonable in merely natural psychological processes is that it cannot be explained how such processes yield justified, reasonable acceptances. Part of explaining how a process can yield justified, reasonable acceptance must, then, involve displaying that the process is justified, and that involves justifying it. So if circularity is impermissible in justification generally, then it is impermissible in the explanatory project as Lehrer conceives it here, where part

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of the explanandum is our acceptances' entitlement to justificatory status, and hence where explanation involves justification. Second, despite Lehrer's confidence, it is not at all clear that explanation can be circular. The very idea of explanation only makes sense, one might suppose (and many have argued), against a backdrop of information taken for granted, and available for service in explanans. Relative to a given explanatory context, this information is taken as surd. But it is this very status that makes explanation, as an attempt to come to understand what is not understood by appeal to what is understood, possible. This also entails that not everything can be explained at once. But that is as it should be. From the fact that appeals to the surd do not explain everything, it does not follow that they explain nothing. Thus the fact that explanation must inevitably appeal to the contextual surd does not mark a kind offlaw in explanation, which would form a suitable second horn of an unhappy dilemma with circularity as the other, and thereby make the circle look no less appealing than the surd. For circular explanations do not explain anything. Rather, they incoherently treat the very same thing as in need of explanation (even if true) and as surd, so not in such need. For this reason, rejecting circular explanation is not merely a matter, as Lehrer suggests, of taking philosophical offence. So I conclude that the retreat from justification to explanation, in the context of showing the reasonableness of coherent justification, fails. If the move to explanation in fact marked more than a merely apparent retreat from justification, it would amount to giving up on the goal of solving the truthconduciveness problem, by assuming it away. Moreover, any purported explanation would be circular, and circular reasoning is no more explanatory than it is probative. And in fact the retreat is only apparent, for explaining how a process merits normative status involves in part displaying its entitlement to that status, by justifying it. But the justification would have to be circular, and fail. Lehrer has certainly not been unaware of the sorts of logical worries with arguing for the reasonableness of our self-trust that I have been belaboring in this paper. Over the years he has been candid and dogged in their face. As we have seen, he has tried on each of the strategies of Agrippa's ancient trilemmaregress, surd foundation, and circle-in defense of his appeal to our own trustworthiness in the context of demonstrating the truth-conduciveness of coherence. He has even tried these concurrently. Lately he has opted for circularity, seeking to avoid the implicit vice by recasting his project as explanatory rather than justificatory. I have been harsh in my assessment of these moves, and have not had to resort to much subtlety in my criticism. Moreover, I am far from their only critic. Yet Lehrer will, no doubt, as he has, persist in his defense of the essential role of self-trust in epistemology. And so he should. For Lehrer is right to recognize the absolutely fundamental

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importance of self trust to the epistemological enterprise, and indeed, to epistemic practice generally. Where he is mistaken is in thinking that an entitlement to self-trust could possibly be argued for at all. It cannot be. Moreover, in a crucial sense, it is not something that can be doubted. 28 As I noted at the outset, epistemic practices are essentially directed at truth. But we should not let the focus on truth blind us to the practice. For a practice to be directed at truth, it must involve the treatment of faculties that generate contentful states as potentially truth disclosing, and the treatment of contentful states as premises in reasoning, which reasoning itself is treated as truth generating (or as at least probabilifying). Now to treat a content generating faculty as potentially truth disclosing in practice is potentially to exploit those contents in reasoning and further inquiry. For a faculty of content generation to be a component of epistemic practice proper, the contents it generates must be treated as truth candidates, since otherwise they would not be involved in a truth directed practice. To involve such contents in a truth directed practice is to exploit them in reasoning, again directed at truth. But to exploit contents in such a manner is to trust that they are true, or at least presumptively so. Moreover, to exploit them in inference is to trust not only them, but also one's competence in inferential matters. This is so no matter how we conceive the psychology ofbeliefformation and reasoning. Suppose the progress of our thoughts were a matter ofHumean associationism, without that progress tracing any demonstrative relations of ideas. Still, despite the lack of any necessary or even clearly probabilifying relations among contents in such an associationist doxastic economy, the links in the associationist chain would be taken by the subject, in practice, to constitute epistemic links. This is revealed in the mind's movement from believed content to believed content, as opposed to the movement from believed or entertained content to entertained content. Indeed the very idea of taking a contentful state to be true implies a self-trust in so taking. Self-trust is also implicit in the authority we have over the contents of our thoughts. And of course the idea that we can reason and evaluate arguments presumes that we can maintain that authority through time. Even doubting a claim presumes that the doubter trusts his own grasp of what he doubts. Nobody who engages in reasoning can at the same time really fail to trust their evaluation of the truth of their second order thoughts. Self-trust is thus at play, and cannot be suspended, in all thinking, even in epistemological or skeptical thinking. For these reasons, self-trust is a condition on the possibility-a transcendental condition, if you will--of epistemic practice. But any attempt to justify self-trust as a blanket matter will involve self-trust, and hence be either circular or involve an infinite regress. But to call self-trust into question, which the idea that it demands justification does, is of course to call into doubt an essential precondition of the practices called upon to justify it, and hence those

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practices themselves. The result is predictable. The practices break down, in the sense that they seem unable to function, and lead to aporia. This shows not that it is unreasonable to trust ourselves, but that self-trust is not a candidate for rational support. Now we do often, in the course of a skeptical challenge to some claim or other, appeal to our own self-trust. But when we do this, we are doing one of two things. We might be citing a limited principle, involving our trustworthiness in this or that context or domain of inquiry, or respecting this or that kind of content. Such limited self-trust can be justified without circularity or regress. Or we might be appealing to a general principle of self-trust, which as we have seen, cannot be justified. But such an appeal should not be construed as a matter of giving a further reason of the same sort as others. Rather, it is a matter of the respondent affirming her status as an epistemic agent, by citing a condition on the entire enterprise of giving and asking for reasons. She is, as it were, citing the rules that make the practice intelligible. And she is citing a rule that all participants in the game perforce accept, in their own case. But of course, to cite the rules of a game is not to make a move in the game. (It is not as if she couldn't give further reasons of the ordinary sort. This suggests that the move really is of a different sort). On this way of thinking, a principle of general self-trust is not a member of one's acceptance system, but a kind of hand-stamper at the door, whose effect is to mark contents as accepted, thereby making them available in truth directed reasoning and justification. Self-trust operates, not as a principle of detachment of an acceptance operator, but to distinguish wh ich among those contents we can think are to be exploited in epistemic inquiry. From the essential ubiquity of self-trust, it follows that all arguments, including all efforts to prove or explain why our coherent, undefeated thinking is truth conducive, will rely on self-trust. But this need not be a problem, for no explicit appeal need be made to general self-trust, from which circularity or regress would have to follow. There is a difference between presuming self-trust and arguing from or for it. The former must be done, the latter cannot. A proper appreciation of the epistemic significance of self-trust, to which Lehrer comes so very close, would shield it from the embarrassments that it suffers when we try to show that we have earned it. But the way Lehrer conceives of selftrust-as a principle which is special, but special among acceptances to be exploited in bootstrapping-forces him to attempt such a showing. Since none can be made, we tug at those bootstraps in vain. This should not be surprising. Bootstrapping is in its nature a futile act. So what is it that has driven Lehrer to such extremes? As we saw, Lehrer gives accounts of justification on two levels, the first subjective and doxastic, the second objective and veridical. The express purpose behind the objective accounts is in each case the avoidance of Gettier and Gettier related

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counterexamples. The basic idea seems to be that personal justification is actually unproblematic excepting in the light of those putative counterexamples. Generating counterexample-proof conditions, and then making sure that personal justification appeals to these measures at a general level, should accordingly restore an individual's knowledge based on her justification. I think the lesson of Gettier is deeper than that. What these examples show is that, in any given case, for justification to yield truth, some external help, the cooperation of the world, is required. Whether we get that needed help in any given case is always a contingent matter, depending on factors outside of the agent's space of reasons. The lesson of Gettier and other cases may be that a certain kind of skepticism, the skepticism which claims that in any given case our justified empirical beliefs may fall short of knowledge, is unavoidable. But that would lend no support, on its own, to the more radical skeptical claim that we might therefor be massively mistaken in what we believe. The gap between personal, doxastic justification and veridical epistemic warrant will seem to need closing, by hook or by crook or by bootstrap, only if we fail to separate these two threats. And we will fail to separate them only if we think that the only way to ensure our grip on reality is through the identification of a justificatory procedure that will give us the ability to weed out the false from the true in our particular beliefs. The coherentist who feels the need for bootstraps shares at least that much with the foundational Cartesian: the urge for a principle the satisfaction of which by any given case of believing will show that belief to be true. While the coherentist has a different kind of principle in mind, it is to serve the same purpose. (They tend to share more than this with the Cartesian as well, including a pernicious subjectivism and a strict internal ism about mental contents, though Descartes himself may not have been a Cartesian in this latter regard). Ifwe reject the demand for such a principle, how then can we reply to the general skeptic? We can say that while the connection between any given truth and belief is contingent, and hence any particular belief is fallible, the connection between belief and truth in general is not contingent. This will not necessarily mean that justification is out as an interesting epistemological analysandum. Surely all the cooperation the world can provide will not make you knowledgeable if you lack the epistemic virtues embodied in the concept(s) of justification. And in this same way we can answer the question which motivated Lehrer's bootstrap in the first place, of how justification, in the light of these results, is epistemic at all. Justification is epistemic because of the intrinsically epistemic nature of what gets justified and does the justifying. But this is an argument for another day. I want to conclude, in this light, with a couple of observations from other contexts in which one speaks of bootstrapping. The image it calls to mind is of some poor supine soul's pitiable and failed attempt to yank himself into standing without pushing off of solid ground, or to achieve some leverage even without

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benefit of Archimedes' one fixed point. In the economic sphere, however, some people are credited with pulling themselves up from destitution "by their own bootstraps", and we admire them for turning the trick. But they do not really do so. They use their labor, skills, wits and guts, each of which can help them rise only if the surrounding world, social and other, complies by valuing and rewarding them. I think a lesson can be drawn from each of these images associated with the notion of bootstraps. First, the perceived need for such desperate epistemic efforts only arises when we think of ourselves as utterly unmoored, unanchored, unconnected to what our beliefs are about. But this supposition is false, as the phenomenon of empirical belief itself shows. Second, we can expect that our own efforts in the epistemic realm, however sincere, coherent, and strenuous they might be, will not achieve their valuable ends without the help of what is outside us: the world and other inquirers. As the related phenomena oflanguage and thought show, we are not without such help.

ENDNOTES * Thanks to Arthur Fine and Meredith Williams for especially valuable comments on earlier versions of this paper. 1 William P. Alston, "Two Types of Foundationalism", pp. 76-94, in Empirical Knowledge, ed. P. Moser ((Rowman and Littlefield 1986). 2 This fourth thesis is widely held by coherentists and thought by some writers to be central to the view. So Donald Davidson, a coherentist, more or less identifies coherentism with the fourth thesis, and John Pollock rejects coherentism precisely because, in his view, the fourth thesis must be false. But it is worth asking whether the only possible coherentism is doxastic coherentism. It is perhaps possible that some factive states with empirical content, such as takings-in of perceptual, memory, and perhaps even testimonial contents (i.e., seeing, remembering, and being told that p), are involved in inferential justification. The obvious problem with this line is that, by the second thesis, in order for such factive states to provide justification, they must themselves be justified inferentially, and it is hard to see how factive states, qua factive, could need or bejustitied by inference. So what is clear is that the contents of such states could not appear in justifications qua [active, but only qua accepted contents. Indeed, in this sense, the way factive states might play a role in justification fully respects the rationale behind the fourth thesis. 3 It is a further objection to coherence accounts that the notion of coherence has been less than fully worked out. But in this regard, coherence is innocent by association; whether or not there are any non-inferentially justified claims to serve as foundations, still it is pretty well agreed upon that some justification is inferential, and that strictly deductive inference is insufficient to support anything like what we regard as justified in our accounts ofthe world. Thus the sorts of relations which figure heavily in coherence accounts, explanatory, unifying and inductive, figure in competing accounts as well. 4 See Bonjour's The Structure of Empirical Knowledge, (Harvard 1985), especially ch. 8.

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Princeton University Press, 1992. See Part Three, and especially the appendix to Chapter 12, at pp. 216-222. 6 One problem for Rescher is his notion of a datum. A datum is not simply a possible truth; it has a stronger claim on veridicality than that, such that it is "to be classed as true, provided that doing so creates no anomalies." Gp. Cit., at p. 166. One may well ask in virtue of what an otherwise mere claim is entitled to this more presumptively alethic status. Rescher has much to say about this concedely crucial issue which I must pass over here. I can say, however, that a metaphysical view like that of the idealists, for whom all claims are connected to the real as abstracta, could be pressed into service here. Likewise the pragmatics of praxis might be invoked on the behalf of the treatment of claims as data. Neither ofthese moves is obviously out of bounds in Rescher's system which is, after all, a pragmatic idealism. 7 In my "Interpreting Davidson's Omniscient Interpreter", Canadian Journal of Philosophy, 1995:335-374, I offer a sympathetic reading of Davidson's anti-skeptical arguments which nonetheless seeks to isolate a central question-begging move in his account. A different, deeper difficulty for Davidson's account is that it treats the external relation in virtue of which beliefs get their contents as purely causal. But as John McDowell has urged, the phenomenon of empirical belief is hard to explain unless mental contents are connected to the world not just causally, but rationally. Absent a rational constraint imposed by the world, it is hard to see how a belief can properly be thought to be about the world, to take a stand with respect to how the world is. Recall here the discussion from footnote two above, involving the possibility that factive states, taken in perceptually or through testimony, for example, can playa role in justification, though not qua factive. Taking in facts about the world in such ways would make our connection to the world a rational one, for facts, unlike causal events, have the form of reasons. In recognizing thatjustifiers may be factive, though notjustifiers qua factive, I am merely resisting what McDowell calls the 'highest common factor conception of experience', which holds that two states which are indistinguishable from the point of view of the agent, and his epistemic justification, are for this reason metaphysically indistinct. In this connection, see McDowell's Mind and World (Harvard University Press 1994) and his "Criteria, Defeasibility, and Knowledge", Proceedings of the British Academy (Oxford University Press 1982) especially section Ill. x Keith Lehrer, "Coherence and the Truth Connection: A Reply to My Critics" [hereinafter CTC], The Current State of the Coherence Theory, ed. John W. Bender (Boston: Kluwer, 1989) 255. Other versions of Lehrer's theory and definitions appear in "Knowledge Reconsidered" [hereinafter KRJ, in Knowledge and Skepticism, ed. Marjorie Clay and Keith Lehrer (Boulder, Co: Westview, 1989) pp. 131-154; and Theory of Knowledge (Boulder, CO: Westview 1990) [hereinafter TK]. 9 KR, p. 136. 10 Towards the end of this paper, I argue that self-trust should be conceived as discriminating which of the contents we can think are to be made available for epistemic practice; that is, it determines which contents we accept, in Lehrer's sense. The members of an acceptance system would not, on my view, have an acceptance operator on them, but would rather simply be contents accepted. But this would not have the effect of making justification trivial, for in justifying something, we put it out of play as ajustifier. Thus, a given accepted content p cannot be appealed to in defeating its own competitors. Moreover, that the particular contents used in epistemic justification are accepted is sufficient to secure the doxastic nature of justification, without the need for an acceptance operator in each case. II Indeed, given that an acceptance's status as personally justified depends upon whether it beats all competitors, and that the agent's acceptance system does not plausibly reflect all the these competitors, it is clear that even personaljustification on Lehrer's account fails to be doxastic. See my "Justified Acceptance, Information and Knowledge" Philosophical Forum, XXV, 1994:212230, for the details of this argument. 12 CTC, p. 253. 5

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TK, p. 122. Lehrer is happy to include in an agent's acceptance system specific acceptances whose contents are denials of specific defeaters, where that is required to preserve intuitions about knowledge in particular contexts, including those not involving essential reliance on falsehoods. He can do this because of the functional character of acceptance. In accepting the things I do, I evidently also accept, with respect to specific possible defeaters, that they do not obtain. Ifmy being cut off from the world, for example, would defeat my claim to true belief about it, then, in accepting that I have such true belief, I evidently accept that I am not cut off from the world. In my "Justified Acceptance, Information, and Knowledge", I urge that this has the consequence of obliterating the distinction between justified and unjustifed beliefs. 15 It is an interesting question whether opacity problems could arise in the context of acceptance for Lehrer. Since acceptance is a functional notion, acceptance being a matter of how contents are actually used in inference, it might be though purely extensional. On the other hand, to the extent that one's behavior in assenting to and dissenting from statements is functional evidence of acceptance, opacity problems might arise. I can assent to "Venus is the morning star" while dissenting from "Venus is the evening star" and can treat these claims differently from a functional standpoint notwithstanding that they are coextensive. 16 Given the functional notion of acceptance, the general iterative principle seems reasonable, and the conjunctive principle is not counter-intuitive. The deductive closure principle is certainly false if taken in its generality. This is why I have used the permissive "may employ" in characterizing the operation of the rules. Thanks, by the way, to Myles Brand, for bringing to my attention a premise missing from a previous formulation of my argument here. 17 Wayne A. Davis and John W. Bender, "Technical Flaws in the Coherence Theory", Synthese 79.2 (1989): 271. 18 KR, p. 143. 19 Lehrer has in fact described his account as an ecumenical reconsideration of externalism, foundationalism, and coherence (TK 173). He acknowledges that he is a sort of a metareliabilist (CTC 263). He admits that Principle T "has many ofthe features ofa basic belief in foundational epistemology," and he has "no objection to the suggestion that ... T ... is a first principle" (KR 145). While this insulates Lehrer's theory as he conceives it from the charge that it fails as coherentism, I am here concerned with it as a coherence theory. Moreover, Lehrer's candor about the impurity of his account does not insulate him from the charge that he, like other ecumenicists, rather than taking the good from the positions he reconciles, has taken the bad from each and lost the benefit of anyone of them. 20 KR, p. 145. 21 KR, p. 146. A grammatical error makes this hard to interpret. 22 TK, p. 124. 23 K. Lehrer, Self-Trust: A Study o/Reason, Knowledge, and Automony (Oxford 1997), p. 22. 13

14

Ibid. Ibid. 26 Ibid. 24 25

This anti-naturalism is made manifest in many places. A particularly clear and worked out argument for the claim that epistemic properties are not natural can be found in chapter 3 of SelfTrust. There Lehrer argues that knowledge does not supervene on any natural properties, since my actual trustworthiness as an acceptor is crucial to knowledge, and "nature is silent about what has worth, what is worthy of our trust, and what is justified" (p. 72). 28 The situation is indeed quite like that which faced Descartes as he tried to ground our knowledge. He recognized that what was needed was a way of defusing the worry that our beliefs might be mistaken, despite our most careful use of our reasoning powers. His method was to attempt to instill this self-confidence by causing us to reflect, first, on our inability to doubt our own existence, and second, on the general features - the clarity and distinctness- of the "I exist" 27

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that make it a practical impossibility to doubt. Descartes' methodology, and the success of his strategy, have of course been subject to repeated attack and refutation. The point I want to make is that Descartes' strategy is of course doomed to fail if it is taken as argument. For any argument for the claim that we can trust ourselves - that what seems clearly to be true to us is true - will of course involve us in trusting ourselves. As Spinoza pointed out, taking the Cogito as an argument would be a serious mistake. Rather, it is a self-standing proposition, "I exist as a thinker", which we are asked to contemplate, to see that it cannot be doubted. The same must be true of Descartes' third meditation "proof' of the principle of clear and distinct perception. If it is taken as a genuine piece of argument, it is manifestly circular both in relying on clearly and distinctly perceived premises and on inferences whose validity is clear and distinct. But unlike the Cogito, this "proof' is hard to treat as a selfstanding proposition for similar contemplation. Perhaps for this reason, Spinoza rejects the need for an epistemic criterion of truth along the lines of Descartes' principle, and holds instead that truth is its own standard.

UNDEFEATED JUSTIFICATION AND THE GETTlER PROBLEM

Chapter 13 LEHRER'S DYNAMIC THEORY OF KNOWLEDGE Hans Rott University ofRegensburg

1.

INTRODUCTION

Philosophers must not be allowed to confuse epistemic and doxastic concepts. It is their duty to clarify the subtle interconnections between knowledge and belief. As this is too formidable a task for a single paper, I will not develop an epistemological theory of my own, but rather focus on Keith Lehrer's influential theory of knowledge as elaborated in his 1990 book Theory ofKnowledge. This book represents only one stage of the development of Lehrer's epistemology. It is the successor of, and shows considerable overlap with, a book with the title Knowledge published by the same author in 1974. The basic structure of the 1990 definition of 'knowledge' is later retained in Lehrer 1997, Chapter 2, and duplicated in an analogous definition of 'wisdom'. The recent second edition of Theory of Knowledge (Lehrer 2000) presents a concept of knowledge that is much simplified as compared to the one of the first edition. I The present paper, however, is based mainly on the more 'dynamic' 1990 version of Lehrer's book. Its purpose is, first, to draw attention to some problematic features of Lehrer's account and, second, to argue that a proper understanding of knowledge does not only require an understanding of belief simpliciter, but in addition a thorough understanding of the dynamics of belief The main point ofthis paper is to show that a good theory of belief rev ision is necessary for a proper development of a theory of knowledge. I shall later also argue that the theory of belief revision can profit from a study of the concepts that have evolved in recent epistemology. We ought to have a basic picture of what knowledge is, and of how knowledge can be obtained, when we search for principled solutions of the problems of belief change. In Rott 2001, I exploit 219 E.1. Olsson (ed.), The Epistemology of Keith Lehrer, 219-242. © 2003 Kluwer Academic Publishers.

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the fundamental distinction between foundationalist and coherentist accounts of knowledge that has played a central role in the epistemological literature of this century. 2 I want to argue that this distinction applies more properly to theories of doxastic states than to theories of epistemic states. It is unfortunate that philosophers have tended to focus on knowledge without attending equally closely to the-seemingly less problematic-notion of belief. Another distinction is not going to be treated in this paper. Externalist accounts of knowledge argue that people or animals need not be able to justify their knowledge, but rather hold that there must be some reliable (causal, counterfactual, nomological) connection between the knower and the things known. Indeed it makes perfect sense to say that, for instance, the dog knows where in the garden its favourite bone is buried, but I want to focus on an internalist and what Lehrer (1990, pp. 4, 36) calls 'characteristically human sort of know 1edge'. To my mind, the verb 'to know' is ambiguous and its variant meanings reflect different and conflicting intuitions-a fact that has caused much unnecessary dispute in recent epistemology. I do not claim to cover all uses of 'to know'.

2.

EPISTEMOLOGY, KNOWLEDGE REPRESENTATION AND REVISION

Arguably, the representation of pieces of knowledge should not differ from the representation of beliefs. From a first-person perspective there is little if anything that allows one to distinguish between mere belief and real knowledge, and it is doubtful whether we should expect the representation of belief and knowledge to represent more than what is accessible to the reasoner or reasoning system itself. Now let us suppose, for the sake of argument, that questions concerning the representation of knowledge and belief have been answered to everybody's satisfaction. Many interesting questions are still left open. Solutions regarding the concept and the representation of knowledge do not automatically give answers to questions concerning the dynamics of belief and knowledge. How is 'knowledge', or better: alleged knowledge, revised in the light of new evidence? How should it be revised? Agents are fallible, and what they consider to be knowledge quite often turns out to be false-and hence not to be proper knowledge at all. At this stage the focus of attention gets shifted from knowledge to belief, and normative questions are seen to become increasingly important. Epistemology, the philosophy of mind and psychology analyse and describe what knowledge is and how it is obtained and represented in human beings. Knowledge representation has to do with normative issues in so far as there are

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many different approaches to representing information, some of which are 'better' and some of which are 'worse'-with respect to what we demand from the relevant 'knowledge systems' (e.g., computational tractability, efficiency, comprehensiveness, reliability, transparency). The change of alleged knowledge, that is, the change of belief and acceptance systems, is intrinsically beset by normative problems as well. It surely is reasonable to ask for an 'ethics' of belief and acceptance. But it seems that this question can be set aside when we talk about knowledge. In so far as 'knowledge' is perceived to be in need of revision, however, it is perceived to be inferior to real knowledge, and should rather be accorded the status of belief, opinion, prejudice or some similar sort of doxastic (rather than epistemic) term. Problems of the ethics of belief arise in so far-and perhaps only in so far-as problems of a genuinely dynamic sort arise. The ethics of belief in the traditional understanding is primarily concerned with the question when it is rational or justified to adopt some new belief, thus involving an act of belief acquisition. 3 The additional problem of belief change is that we have to face the question when to eliminate or replace which of the previously held beliefs, thus involving acts of belief dislodgement. Primajacie, it appears that the questions posed by epistemology, knowledge representation and 'knowledge' revision are, though related, clearly separable. In any case, there does not seem to be a close connection between the theory of knowledge and the theory of belief revision. It is the thesis of the present paper that precisely this is illusory. Even if we do not contemplate any problems of the 'intermediate' field of knowledge representation, we can find very close interdependencies of epistemology and belief revision. More precisely, I want to illustrate that (i) the analysis of knowledge requires a proper solution of the problem of belief revision; (ii) the analysis of belief revision should not be conducted without a proper understanding of the concepts and categories that have been used in study of knowledge. We must actually restrict claim (i) considerably because the following considerations will be based on the particular epistemological theory of Keith Lehrer. I take Lehrer to be following in great detail a trail that was started by Plato, in a beautiful passage in one of his earlier dialogues: True opinions too are a fine thing and altogether good in their effects so long as they stay with one, but they won't willingly stay long and instead run away from a person's soul, so they're not worth much until one ties them down by reasoning out the explanation .... And when they've been

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LEHRER'S DYNAMIC THEORY OF KNOWLEDGE tied down, then for one thing they become items of knowledge, and for another, pennanent. And that's what makes knowledge more valuable than right opinion, and the way knowledge differs from right opinion is by being tied down. (Meno 97e-98a, Plato 1994, p. 69)

Most of the following considerations will not depend on the details of Lehrer's theory; in fact I shall offer a few non-trivial improvements on some of his definitions. But I want to base my arguments on the overall architecture of Lehrer's undertaking. If Lehrer were completely misguided, then what I say about the relation between epistemology and the theory of belief revision might equally well be mistaken. Claim (ii) needs to be qualified as well. The analysis of belief revision is not dependent on features that distinguish genuine knowledge from mere belief. It is rather dependent on the structure and the fonnation of beliefs as they are relevant in the theory of knowledge. What I have in mind above all is the fundamental distinction between foundations and coherence theories of knowledge. This distinction happens to have come to the fore in the theory of knowledge, but it may just as well be placed in a theory ofbelief. 4 It is primarily concerned with the inferential relations between various beliefs, that is to say, with the internal structure of our belief systems. The contrast lies in the answer to the question whether there is such a thing as a belief base, that is, a distinguished set of beliefs that are not in need of an inferential justification by other beliefs and that taken together inferentially justify all the remaining ('derived') beliefs. All of this can be dealt with in a general theory of belief; nothing requires to refer this topic to the theory of knowledge. Claim (ii) can still be upheld, given the fact that many relevant aspects of the structure of beliefs have as a matter of fact come out most clearly in epistemological discussions.

3.

CENTRAL CONCEPTS OF LEHRER'S THEORY OF KNOWLEDGE

In this section we unroll the central parts of Lehrer's theory of knowledge and show how they are rooted in problems and questions which belong to the theory of belief change. The following presentation is based on the summary in Lehrer 1990, pp. 147-149. The time parameter t which does not play any interesting role in Lehrer's theory will be removed. For a long time it has been thought in philosophy that knowledge is justified true belief. The short and famous article by Gettier published in 1963 has made it clear that this analysis is inadequate. Let us have a look at one of Gettier's counterexamples. Suppose that Smith has very strong evidence for

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cp: Jones owns a Ford.

Suppose further that Smith is totally ignorant of Brown's whereabouts. Still he can (and does) correctly infer from cp that 7/J : Either Jones owns a Ford, or Brown is in Boston.

X : Either Jones owns a Ford, or Brown is in Barcelona. ~:

Either Jones owns a Ford, or Brown is in Brest-Litovsk.

By pure coincidence, and entirely unknown to Smith, Barcelona happens to be the place where Brown actually is. However, Jones does not own a Ford. Now, X is a true justified belief, since cp is a justified belief and and X may be logically derived from cp, and the second disjunct of X is true. However, it would be utterly counterintuitive to say that Smith knows that X is true, because he believes that X is true 'for the wrong reasons'. He has just been lucky that the right belief occurred to him. 5 Gettier's example has led many epistemologists to the conclusion that knowledge is more than justified true belief. They do not discard this venerable definition of knowledge, but supplement it by a fourth clause. Lehrer's suggestion is the following: DK

S knows that cp if and only if (i) S accepts that cp, (ii) it is true that cp, (iii) S is completely justified in accepting that cp, and (iv) S is completely justified in accepting that cp in a way that does not depend on any false statement.

Although Lehrer (1990, pp. 10-11) separates acceptance from belief, I do not think that it would make a big difference if we substituted belief for acceptance in clause (i). 6 Similarly, clause (ii) is not very controversial in the theory of knowledge. The essential parts of the definition are the last two clauses which appeal to the problematic notions of justification and dependence. I have substituted in clause (iv) a formulation taken from Lehrer 1990, p. 18, for the formulation in his official summary in Lehrer 1990, p. 147. In the latter he requires S to be completely justified in accepting that cp 'in a way that is not defeated by any false statement'. This statement seems to be slightly screwed up. What Lehrer means, I think, is that S is completely justified in accepting that cp in a way that cannot be defeated by pointing out that the justification

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relies on a false statement. The above phrasing of clause (iv) expresses this more accurately than Lehrer's official formulation. 7 Lehrer further characterizes the concept of knowledge in a two-layered strategy.8 First he develops the notion of personal justification which is based on an agent's subjective acceptance system. In a second step the purely subjective standpoint gets transcended by several operations on the agent's current belief set that could help him to approximate the whole truth. 9 3.1.

Personal Justification and the Comparative Reasonableness of Acceptance

All of Lehrer's considerations are based on the notion of an acceptance system which is defined as follows. \0 We slightly adapt the notation. D1

A system X is an acceptance system of S if and only if X contains just statements of the form, 'S accepts that cp', attributing to S just those things that S accepts with the objective of accepting that cp if and only if cpo

This definition could be amended a little by taking into account that on Lehrer's account, there is only one acceptance system for each agent at a certain time. So it seems that D1 should better start like that: 'A system X is the acceptance system of S if and only if ... ' Lehrer is one of the main advocates of a coherence theory of know ledge. According to this approach, all justification comes from coherence with a given acceptance system X. There is no justification simpliciter, only justification on the basis of some X. D2

S is justified in accepting cp on the basis of system X of S if and only if cp coheres with X of S.

What is needed now is of course an elucidation of 'coherence-with-asystem'. Lehrer defines it in terms of the relations of competing, beating and neutralizing of propositions. D3

cp coheres with X of S if and only if all competitors of cp are beaten or neutralized for S on X. 11

Interestingly, Lehrer does not seem to require that cp belongs to X for D2 and D3. The function that takes an acceptance system X and yields back the set of all sentences cohering with X, or equivalently, of all sentences S is justified in accepting on the basis of X, may be interpreted as an inference operation in the sense of Rott 2001. D4

1/J competes with cp for S on X 12 if and only if it is more reasonable for S to accept that cp on the assumption that 1/J is false than on the assumption

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that 'IjJ is true, on the basis of X. D5

cp beats 'IjJ for Son X13 if and only if'IjJ competes with cp for S on X, and it is more reasonable for S to accept cp than to accept 'IjJ on X.

D6

X neutralizes 'IjJ as a competitor of cp for S on X if and only if'IjJ competes with cp for S on X, but 'IjJ 1\ X does not compete with cp for S on X, and it is as reasonable for S to accept 'IjJ 1\ X as to accept 'IjJ alone on X.

Intuitively, definitions D4 and D5 are not beyond reproach. Let us assume, for instance, that it is extremely reasonable to accept that cp, and that 'IjJ weakens the reasonableness of accepting cp just a little bit, by a more or less negligible degree. Should we say that 'IjJ 'competes with' cp? In what sense would we speak of a competition? The proposition 'IjJ may be about quite another subject matter than cp, so there cannot be much rivalry or conflict between the two. And again, if it is still a little more reasonable to accept cp than to accept 'IjJ, should we say that cp 'beats' 'IjJ? Surely in the situation just described it would make good sense to accept both cp and 'IjJ (assuming that it is reasonable to accept 'IjJ in the first place), even if cp beats 'IjJ in Lehrer's sense. We are ready to accept sentences that weaken each other a little, and we tend to connect such sentences by 'although'. Ifwe say, 'They get along together very well, although they have no interests in common', in symbols 'cp although 'IjJ', we do accept both cp and 'IjJ. It does not matter that 'IjJ 'competes with' cp in Lehrer's sense, and it does not matter whether cp 'beats' 'IjJ or not. The last three definitions, D4-D6, all lead us to a comparative concept 'reasonable-to-accept', relativized to a given acceptance system X. Before turning to a brief discussion of that concept, we finish off the first, subjective part of Lehrer's analysis of knowledge. For personal justification, it is just the agent's current acceptance system which is the basis for judgements of coherence. D7

S is personally justified in accepting that cp if and only if S is justified in accepting that cp on the basis of the acceptance system of S.

Now of course everything hinges on what is meant by 'reasonable-toaccept' -again, relativized to a given acceptance system. Surprisingly, Lehrer does not say very much about this, but he considers it as an advantage that his primitive term of reasonableness is open to many different interpretations. In the few pages he devotes to the topic (Lehrer 1990, pp. 127-131), however, he recommends to employ cognitive decision theory.14 Lehrer suggests to identify the degree of reasonableness of accepting a hypothesis cp with its expected epistemic utility:

r(cp)

p(cp) . Ut(cp)

+

p(...,cp). Uf(cp),

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where p( cp) and p( ---,cp) = 1 - p( cp) are the probabilities of cp being true or false respectively, and Ut( cp) and Ufi cp) are the positive or negative utilities of accepting the hypothesis cp, when cp is true or false, respectively. The utility Ut( cp) is supposed to reflect the informativeness of cp, and possibly other virtues such as cp's explanatory power, simplicity, or pragmatic value, and the advantage of conserving existing beliefs (Lehrer 1990, p. 131). It should be noted that this absolute degree of reasonableness of accepting is not quite sufficient for what we need in order to understand the foregoing definitions. In the definition of competition, Lehrer appeals to the reasonableness of accepting cp on the assumption that?j; is true or false. What we need, then, is something like expected conditional epistemic utilities r( cp!?j;) and r(cp!---,?j;), and it is left unspecified how we can get them. There is no problem with the well-known concept of conditional probabilities,15 but it is not quite clear whether the utilities of accepting a hypothesis cp conditional on accepting ?j; or ---,?j; should be thought of as different from the plain, unconditional utility of accepting cpo But if the utility of accepting a sentence is dependent on accepting some other sentence, should not the utility of accepting a sentence be sensitive to the context of acceptance, that is, to the acceptance system X as a whole? This question leads us to a problem that is both more general and more important. As indicated in definitions D4-D6, the reasonableness of accepting a statement may be-and probably should be-relative to the acceptance system of the agent. But the above definition of r( cp) does not reflect this. It is rather an absolute measure of reasonableness. This is quite contrary to the coherentist's aim of evaluating systems of hypotheses rather than single hypotheses taken in isolation. Lehrer can counter this objection by saying that the utility functions Ut and Uf depend on the current acceptance system X. But then one may ask whether it is illuminating to base an analysis of 'coherence of cp with a system X' on an unexplained notion of 'utility of accepting cp on the basis of systemX,.16 Appealing to cognitive decision theory suggests that the acceptance of a proposition is a matter of decision. Such an assumption is at least controversial. But in this respect Lehrer's replacement of 'belief' by 'acceptance' is a prudent move. It is certainly much more plausible to say that an agent decides to accept something than that he decides to believe something. Another potential point of criticism is that it need not be (objective? subjective?) probability that is taken into account when the reasonableness of accepting certain hypotheses gets assessed. Perhaps plausibility, a notion with different formal characteristics, is an equally suitable candidate. This objection, too, could be countered, by pointing out that decision theory is simply a theory based on probabilities. 17

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Varying Imperatives for Coherence

The most serious questions for Lehrer's account seem to be the following. How can we be sure that coherence in his sense, explained by means of a complicated mechanism of competing, beating and neutralizing, which in turn is based on a decision-theoretic criterion, will give us a coherent acceptance set? 18 If every element of an acceptance set coheres with that very set (as it presumably should), can we be sure that the acceptance set is consistent? 19 Will the acceptance set be closed under logical consequences? Both consistency and closure are themselves requirements of-inferential-coherence. If all of Lehrer's central definitions are finally based on a numerical degree of reasonableness, why not take that very same degree as the sole arbiter of acceptance, without the taxing detour via definitions D2-D7? All these questions call for a fresh and systematic look at the principles that are involved in Lehrer's concept of coherence. First and foremost, we have coherence according to Lehrer's own theory. The corresponding imperative is this: Accept precisely those sentences the competitors ofwhich are beaten or neutralized! Second, we have seen that Lehrer's theory is grafted on top of cognitive decision theory which of course brings along its own standards of coherence. Lehrer does not address this point. An attempt to make it explicit reveals that there are several ways to go. The following idea seems initially plausible: Accept those sentences that promise the greatest expected cognitive utility! A moment's reflection, however, shows that this idea is premature. Why should we reject sentences of positive (or at least non-negative) expected utility for the sole reason that there are still more useful ones? Don't all sentences with positive r-values contribute to the overall expected utility? Thus the right imperative seems to be this: Accept all sentences with positive (or non-negative) expected cognitive utilitypo But perhaps this is again mistaken. It may be wrong to suppose that the utilities of individual sentences simply add up to yield the utility of the whole body of beliefs. This would mean that we cannot rely on the above imperatives, because conditional utilities (see above) may be very different from the unconditional ones. For instance, I may entertain two alternative hypotheses, both with high expected epistemic utility, which contradict each other. Accepting either one of them seems reasonable, but accepting both of them would lead to inconsistency which is not particularly useful. Thus one should take into account interactions between the individual beliefs, and regard beliefs as constituting a system that may be assessed only holistically. This is very much in the spirit of coherentists anyway, who argue that only the corpus of belief or knowledge taken as a whole is a proper unit of epistemic appraisal. The degree r of reasonableness of acceptance then must not be applied to in-

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dividual sentences, but to sets of sentences, and the corresponding imperative reads thus: Accept those sets of sentences that promise the greatest expected cognitive utility! A third concept of coherence is the logical or inferential one. I shall discuss its implications in detail later, but it is expedient to anticipate the main points already here. A set of sentences is inferentially coherent if it is consistent and closed under consequences. The corresponding imperative is: Accept all the logical consequences of what you accept, but avoid accepting contradictions! In Rott 2001, Chapters 7 and 8, it is shown that the second and the third concepts of coherence are compatible with one another. But even if one is ready to grant Lehrer's mechanics of justification in the sense of his definitions D3-D6 some plausibility in itself, it is doubtful whether it can be made to cohere with other concepts of coherence. One has to face the fact that different coherence criteria may conflict with one another, and decide which of these criteria are the most justified ones. As of 1990, Lehrer's theory is a hybrid of at least three different intuitions. 3.3.

Undefeated Justification and Justification Games

In order to arrive at knowledge one has to go beyond the actual acceptance system of an individual agent. In a sense very close to the passage of Plato's Meno quoted in Section 2 above, knowledge must be stable under criticism. In Lehrer's 'justification games' the part of the critic is taken over by an omniscient 'sceptic'. Let us now have a look at the formal definitions that take Lehrer from merely personal justification to complete and indeed indefeasible justification. D8

A system V is a verific system of S if and only if V is a subsystem of the acceptance system of S resulting from eliminating all statements of the form, 'S accepts that cp', when cp is false.

As in the case of definition D 1, it would be preferable to say that the V mentioned in D8 is the verific system of S, since it results from the unique acceptance system of S (at a given time) by just cutting out the false beliefs. The verific system is the basis for verific and complete justification: D9

S is verifically justified in accepting that cp if and only if S is justified in accepting that cp on the basis of the verific system of S.

D lOS is completely justified in accepting that cp if and only if S is personally justified in accepting cp and S is verifically justified in accepting cpo Complete justification in this sense, however, does not solve the Gettier problem. Smith's belief that Jones owns a Ford need not depend on any false

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belief. Let us suppose that Jones told Smith that he has a Ford, showed him papers stating that he, Jones, owns a Ford, and always drives a Ford on his way from his home to his office. All this is believed and known (in some pretheoretical sense) by Smith, and justifies his belief that Smith does in fact own a Ford. So the reason for Smith's not knowing that sentence X above is true is not that he accepts false sentences, but rather that he is not aware of all true sentences that are relevant to the case. Notice that it is not enough to know some relevant facts since a biased selection of true facts may be utterly misleading and tum the agent away from some other truths. Lehrer suggests to solve this difficulty be looking at what he calls the 'ultrasystem' of an agent. Here are his definitions. D 11

S is justified in accepting that cp in a way that is undefeated if and only if S is justified in accepting cp on the basis of every system that is a member of the ultrasystem of S.

D12

A system M is a member of the ultrasystem of S if and only if either M is the acceptance system of S or results from - eliminating one or more statements of the form, 'S accepts that 1/)' , when 'ljJ is false, - replacing one or more statements of the form, 'S accepts that 1jJ' , with a statement of the form'S accepts that not 'ljJ', when .1jJ is false, - or any combination of such eliminations and replacements in the acceptance system of S, with the constraint that if'ljJ logically entails X which is false and also accepted, then'S accepts that X' must also be eliminated or replaced just as'S accepts that 'ljJ' was.

Before moving on to the criticism of Lehrer's, we should mention his key result: 'Knowledge reduces to undefeated justification, a just reward for our arduous analytical efforts.' (Lehrer 1990, p. 149) Clearly, undefeated justification implies personal justification: the actual acceptance system of S is a member of the ultrasystem; it also implies verific justification: the sceptic can make S eliminate all his false beliefs, thus effecting a transition to the agent's verific system;21 finally, it also implies truth: if cp were false, the sceptic could make S eliminate cpo Lehrer's theory of knowledge can be called a dynamic one because we can think of the repeated operations mentioned in D 12 as (potential) steps in a journey through the space of belief states.

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One may wonder why Lehrer requires for the undefeated justification of ip that every member of the ultrasystem must support ip. It would seem sufficient that S is ultimately justified. By this we mean that for every member M of the ultrasystem of S there is another member M' of the ultrasystem of S which improves on M and on the basis of which S is justified in accepting ip. That NI' improves on M means, of course, that M' can be reached from M by some combination of 'truth-conducive' eliminations and replacements of the kind specified in definition D12. This concept seems more adequate since even if S knows that ip, pre-theoretically understood, a mischievous sceptic may well advance an impressive battery of true facts speaking against the truth of ip, so that S looses his confidence that ip is true. Only later in his conversation with the omniscient sceptic, when S comes to know more about the truth, will he regain his old true and justified belief. Although the correct belief would be dropped on the receipt of true but misleading information, we may consider it to constitute knowledge, since one can later learn that this information has in fact been misleading. Temporary doubts about ip should not count, so it seems, as long as all potential paths of the ultra justification game finally lead to ip'S acceptance. 22 Lehrer himself seems to agree with that when discussing his Grabit example: 23 Suppose I see a man, Tom Grabit, with whom I am acquainted and have seen often before, standing a few yards from me in the library. I observe him take a book off the shelf and leave the library. I am justified in accepting that Tom Grabit took a book, and, assuming he did take it, I know that he did. Imagine, however, that Tom Grabit's father has, quite unknown to me, told someone that Tom was not in town today, but his identical twin brother, John, who he himself often confuses with Tom, is in town at the library getting a book. Had I known that Tom's father said this, I would not have been justified in accepting that I saw Tom Grabit take the book, for if Mr. Grabit confuses Tom for John, as he says, then I might surely have done so, too. (Lehrer 1990, p. 139)

Lehrer summarizes the lesson to be drawn from this example as follows: 'I may be said to know that Tom Grabit took the book despite the fact that, had I known what his father said without knowing about his [the father's] madness, I would not know whether it was Tom who took it.' In contrast to Lehrer's undefeated justification, ultimate justification no longer implies that S is justified on the basis of his current personal or verific acceptance systems. But what we have been looking for is an objectified notion of justification, which can be conjunctively added to the (at least partially) subjective notions of personal and verific justification. In particular, we cannot dispense with verific justification if we want to end up with the right analysis of Gettier-type examples. In the example discussed on page 222, Smith is both

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personally and ultimately justified in believing that either Jones owns a Ford or Brown is in Barcelona (0. What prevents him from knowing this is that his belief that Jones owns a Ford is false, so he is not verifically justified to believe that ~.24 Ultimate justification is not sufficient for knowledge. Since every theory can be improved by a transition to the one true and complete theory about the world,25 ultimate justification reduces to justification on the basis of that theory. On the one hand, it does not seem objectionable to call for that theory as the final arbiter of knowledge. On the other hand, I cannot see why the whole truth must be coherent, in Lehrer's or in any other but the purely logical sense. Shouldn't we try to avoid stipulating that the one true and complete theory is coherent, because that would mean basing epistemology on a questionable metaphysics? Similarly, I do not see any intuitive reason why every truth should be justified, on the basis of the true and complete theory. If this is right, then it is impossible, by Lehrer's own definition of knowledge as well as by the definition using ultimate justification, that an agent will know the whole truth. Shouldn't we try to avoid this conclusion? This suggests that undefeated justification may not be necessary for knowledge, and even ultimate justification may not be. But let us stop with these cosmic speculations now and return to more definite matters again. In Lehrer 2000, especially pp. 153-154, 168-169, there are no replacements any more, and there is no talk of strong corrections. In this new account, the ultrasystem is closer in essence to what was called the verific system earlier,26 and undefeated justification is similar to verific justification, i.e., justification on what remains when everything false is eliminated from the person's acceptance system. Unfortunately, Lehrer does not tell the reader why he has changed his earlier definitions and given up on the idea that not only eliminations, but replacements, too, may be prompted by the sceptic. It is not clear whether he just considers it as a simplification of his former account or whether he thinks that the new edition of his book actually corrects an inadequacy of his former account. I presume that the reason lies in the problem of misleading information. In cases like the Grabit example, receipt of information about what Tom Grabit's father said (without information about the father's mental state) would probably have done away my acceptance that Tom Grabit stole the book, even though this seems to be a bit of genuine knowledge. So it appears that according to Lehrer, we should not admit replacements or additions to our stock of accepted propositions when testing for knowledge. This is an interesting argument, but its validity may well be doubted. Misleading effects cannot only be achieved by adding truths but also by removing falsehoods. There are other cases of a similar structure where in fact no genuine knowledge seems to be in-

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volved. Lehrer (2000, p. 160) discusses a 'newspaper example' originally due to Harman (1973). I do not think, however, that the distinguishing criterion offered does the job that it has been assigned by Lehrer. In the newspaper example, the subject's justification is said to depend on "unstated" facts about the newspaper's trustworthiness. But then, why are we not to assume, for instance, that the justification of our belief that Grabit stole the book depends on the unstated fact that no-one has offered any evidence about look-alike suspects? Ifwe can't rule out this, we don't seem to know that Grabit stole the book, according to Lehrer's definition, and the strategy of using only eliminations, rather than both eliminations and replacements, does not help. In sum, then, I cannot see that there is an epistemologically significant difference between the sceptic's removing errors and his supplying new truthful information. Sometimes misleading evidence that one does not possess may block the claim to knowledge, just as wrong beliefs that one does possess may do.27 Whenever the omniscient sceptic succeeds in making us abandon a belief as a result of an improvement of our belief set, this is strong indication that the belief has not been a piece of knowledge. Knowledge, so it seems, should be stable in any kind of critical, truth-directed dialogue. For this reason I will stick to the richer 1990 definition of ultrasystems.

4.

LEHRER'S LOGICAL CONSTRAINTS FOR ELIMINATIONS AND REPLACEMENTS, AND HOW TO IMPROVE THEM

We have seen that eliminations and replacements of accepted propositions are of paramount importance for Lehrer's approach to the theory of knowledge. Eliminations and replacements are respectively called 'weak corrections' and 'strong corrections' in Lehrer 1997, pp. 45-49. These operations are very close to the operations of contraction and revision as they are known in the theory of belief revision. 28 As Lehrer places no constraints on the structure of acceptance systems (see Definition D1), there seems to be no need for him to apply nontrivial change operations to acceptance systems. 29 May we not just eliminate a false sentence 1jJ by simply dropping the statement' 5 accepts that 1jJ' from the system X, and similarly, may we not simply substitute the statement' 5 accepts that -,1jJ' for the statement '5 accepts that 1jJ' in X, when a false sentence 1jJ is to be replaced by its negation? The answer is, 'No'. Effortless eliminations and replacements are excluded by the logical constraint stated in Lehrer's definition D 12: 'if 1jJ logically entails X which is false and also accepted, then "5 accepts that X" must also be eliminated or replaced just as "5 accepts that 1jJ" was.,30

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These are the only constraints Lehrer enters into his official definitions, but in the running text he acknowledges more constraints of a similar kind. They are in a sense complementary to the ones we just mentioned. Let 7/J again be the false sentence to be eliminated or replaced by its negation -,7/J. While the first group of constraints concerns (false) sentences implied by 7/J, the second group deals with (necessarily false) sentences implying 7/J. The first group of constraints is forward-looking, the second group is backward-looking. Here is the quotation from Lehrer 1990, p. 141: The sceptic ... may require the claimant to eliminate anything the claimant accepts that is false, and the claimant must eliminate the specified item from his acceptance system and at the same time eliminate anything he accepts that 10gicaIIy implies the eliminated item. Or the sceptic may require the claimant to replace anything the claimant accepts that is false with the acceptance of its denial and at the same time replace anything that 10gicaIIy implies the replaced item with acceptance of its denial. [My italics]

In order to make the discussion of Lehrer's logical constraints more easily surveyable, I will now give shorter, semi-formalized formulations. (FE)

Forward Elimination. If 7/J is to be eliminated and 7/J f- X, then item X, if false, must be eliminated.

(FR)

Forward Replacement. If 7/J is to be replaced by item X, iffalse, must be replaced by -'X.

(BE)

Backward Elimination. If 7/J is to be eliminated and X fitem X (which is false) must be eliminated.

(BE)

Backward Replacement. If 7/J is to be replaced by item X (which is false) must be replaced by -,x.

-'7/J and 7/J f- X, then 7/J, then

-'7/J and X f- 7/J, then

I have not mentioned here that only X's that are accepted should possibly be eliminated or replaced. This should be self-evident. I am not going to discuss the falsity conditions in (FE) and (FR), which presume an impartial, objective, omniscient supervisor for the eliminations and replacements in the 'ultra justification game'. I want to reflect on the logical constraints only in so far as they are accessible to the agent himself. In doing so, I want to avoid the assumption that the agent is or should be omniscient; however, I do embrace the idealizing assumption that he or she is capable of drawing all and only valid logical inferences that can be drawn on the basis of their acceptance systems. The point I want to make is that Lehrer's logical constraints are too simplistic. Being based on consequence relations between single sentences, they in

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effect consider the accepted items in isolation rather than as items in an acceptance system. The constraints do not really address the logical coherence of a belief with all its surrounding beliefs. It is important to take into account the context of the remaining accepted items when formulating logical constraints for eliminations and replacements. Without any claim that these are 'the right' constraints, the following ones are certainly more adequate in that they show some sensitivity to the context in which beliefs are situated. We keep on using the variable '1jJ' for the false sentence that is to be eliminated or replaced by its negation, and give both a formulation that is close to Lehrer's own statements and a slightly more formalized version. (FE-)/(FR -) Forward Elimination/Forward Replacement. If 1jJ is an essential premise for the logical derivation of X and X is false, then'S accepts that X' must also be eliminated. In symbols:

If 1jJ is to be eliminated or replaced by -,1jJ, and F U {1jJ} I- X for some set F of accepted items which are not eliminated, but F }L X for any such F, then item X (if false) must be eliminated. (FR +)

Forward Replacement.

If the addition of -,1jJ creates a new implication of ~ (and ~ is true) then 'S accepts that t must be added to the acceptance system. In symbols: If 1jJ is to be replaced by -,1jJ, and F U {-,1jJ} I- ~ for some set F of accepted items which are not eliminated, then item ~ (if true) must be added, if it is not already accepted. (BE-)l(BR -) Backward Elimination/Backward Replacement. If F is a set of accepted premises that logically implies the eliminated or replaced item 1jJ, then for at least one (false) member X of F, 'S accepts that X' must be eliminated. In symbols: If 1jJ is to be eliminated or replaced by -,1jJ, and F I- 1jJ for some set F of items, then at least one member of F (which is false) must be eliminated. These conditions correct a number of counterintuitive features of Lehrer's constraints. In the case of a replacement of 1jJ by -,1jJ, there is no reason to replace by their negations all the X's that are either critically implying 1jJ or essentially implied by 1jJ. It is enough that such X's are eliminated. Let us temporarily employ the following concepts of critical and essential implication. A sentence X critically implies another sentence 1jJ in the context of a set F, if F implies 1jJ, F \ {X} does not imply 1jJ, and X is one of 'the weakest' or

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'most vulnerable' elements of F. A sentence X is essentially implied by another sentence 1/J in the context of a set F, if F implies X, but F \ {1/J} does not imply X. Critically implying and essentially implied X's are to be eliminated when 1/J is just eliminated without being replaced by its negation. And in this respect, there is no reason at all to think that replacements present problems any different from those presented by contractions. However, a replacement occasions one kind of adjustment of the acceptance system which cannot be initiated by an elimination. Since there is an addition of -'1/J to the old acceptance system, it is reasonable to require that any new derivations that are made possible by this new item should in fact be made, and the results be added to the acceptance system. This is condition (FR+) which has no counterpart in Lehrer's definitions. The most important respect in which the above constraints improve upon Lehrer's constraints is that they pay attention to the fact that 1/J or any of the X's mentioned are part of a system. The F's mentioned in the constraints represent the contexts in which the respective tests for implications have to be made. The contexts are subsystems of the original acceptance system of the agent. By making the contexts explicit, we raise important new questions: Which items may be included in those F's that figure in the forward-looking constraints? Which items should be excluded from those F's that figure in the backwardlooking constraint? More generally, how do we know which items in an acceptance system survive the process of elimination or replacement? Lehrer should give answers to these questions if his theory of knowledge is to be considered complete, but he fails to do so. It is precisely the theory of belief change that addresses these questions and offers a variety of ways to answer them. The constraints (BE-) and (BR-), which concern sets'F that imply the false belief 1/J that has to be given up or replaced, leave much room for choices. It requires the agent to give up at least one (false) belief in F, but it does not tell us which belief or beliefs ought to be given up. The constraint does not fully determine what to do, but leaves us the freedom to choose. But how are the choices which members to eliminate from the acceptance set to be made? Even if one cannot enumerate concretely the cognitive values that govern our decisions what to give up, it is possible to inquire into the logic of 'coherent' or 'rational' choices involved in belief change (Rott 2001), A choice-theoretic perspective has already come up in Lehrer's suggestion to explicate the notion of personal justification. We saw that he ends up with a decision-theoretic explication ofthe comparative notion of reasonableness-ofacceptance. According to this approach, it is more reasonable to accept 'P than to accept 1/J just in case 'P has greater expected epistemic utility than 1/J, But this is a comparison between two single items of belief only, and it is not clear how

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it can be extended to a criterion for assessing whole systems of belief. In fact it is not at all evident that the logical constraints that Lehrer mentions on his way from personal to undefeated justification mix well with the decision-theoretic advice given in the case of personal justifications. It has to be shown that a combination of logical and choice-theoretic constraints is indeed possible. In Rott 2001, I have tried to show this independently of Lehrer's particular idea that go for maximal or at least non-negative expected epistemic utility. Using choice-theoretic methods, one can maintain the idea that acceptance systems resulting after some change ought to be inferentially coherent, that is, consistent and closed with respect to a given logic. Choice and logic can indeed coexist in harmonyY It is unclear whether Lehrer's coherence mechanics in terms of competing, beating and neutralizing is compatible with such an account, but what seems to be clear is that both logic and the theories of choice and decision are better motivated and more principled than Lehrer's coherence mechanics. In case of conflict, they might therefore take priority.

5.

EPISTEMOLOGY AND BELIEF CHANGE A SYMBIOTIC RELATIONSHIP

In this paper, I have used concepts and ideas borrowed from belief revision theory to elaborate on an important contemporary account in the theory of knowledge. But the symbiosis between the two research areas may equally well be viewed from the opposite perspective. In this concluding section, I want to give an indication of how concepts and ideas developed in epistemology can help to structure and interpret much of the work that has been done in belief revision theory. One of the most relevant distinctions for belief revision is that between foundationalist and coherentist approaches in epistemology. Lehrer (1990, p. 13) characterizes the fundamental difference between foundationalist and coherentist views of knowledge as follows. According to foundationalists, knowledge and justification are based on some sort of foundation, the first premises of justification. These premises provide us with basic beliefs that are justified in themselves, or selfjustified beliefs, upon which the justification for all other beliefs rests. Coherentists argue that justification must be distinguished from argumentation and reasoning. For them, there need not be any basic beliefs because all beliefs may be justified by their relation to others by mutual support. [My italics, HR]

Ernest Sosa (1980, pp. 23-24) makes essentially the same point in more metaphorical terms:

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For the foundationalist, every piece of knowledge stands at the apex of a pyramid that rests on stable and secure foundations whose stability and security does not derive from the upper stories or sections. For the coherentist a body ofknowledge is a free-floating raft every plank of which helps directly or indirectly to keep all the others in place, and no plank of which would retain its status with no help from the others. [My italics]

It is important to see that the categorical distinction between foundationalism and coherentism can more properly be applied to theories of belief than to theories of knowledge, since no reference is made in the drawing of this distinction to the question of whether the beliefs in question are actually true. 32 There is also a second, more 'dynamic' sense in which the distinction becomes relevant, and that is when it comes to the modelling of the dynamics of belief. 33 So there are two questions that separate foundationalists from coherentists. (1) Can a distinction between basic beliefs and derived beliefs be validly drawn? (2) And if so, are changes of beliefs made primarily on the base level or on the level of 'coherent theories'? It is clear what the foundationalist's and the coherentist's answers will look like. The former af'finns while the latter denies the first question. In response to the second question, the former would say' on the base level', while the latter, lacking a distinguished base level, must opt for the level of coherent theories. It is necessary to work out in greater detail the concepts and distinctions on which these answers are based. In Rott 2001 I have tried to provide a framework that helps us to understand the issues involved and to characterize two fundamentally different perspectives on the process of belief revision. These perspectives turned out to be related to, but not identical with, the dichotomy between foundationalism and coherentism. I did not go as far, however, as Hansson and Olsson (1999) who argue that the coherence theory in the epistemologist's sense is trivialized in the context of the coherence perspective on belief revision. When transferring the idea of 'foundations' of knowledge to the area of belief change, it is not particularly important whether the basic beliefs are true, let alone infallibly true. Neither is it important that they are justified to such a high degree that they may be regarded as certain. In the current theories of belief change, belief bases are not supposed to carry any of these connotations. Basic beliefs are distinguished from derived beliefs only by the fact that they are somehow 'given', either explicitly or as things that are taken for granted. Givenness is not at all supposed to imply indefeasibility here. Still, as I tried to

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show in Rott 2001, these categories coming from epistemology can be exploited for an illuminating analysis of the dynamics of belief. Acknowledgements. This paper is a revised version of the second chapter of Rott 2001. I want to thank Gordian Haas, Keith Lehrer, Erik Olsson, Wolfgang Spohn and all the other participants of the 2000 Konstanz Workshop on Lehrer's epistemology for many helpful comments, even though they will certainly be dissatisfied with what I made out of them.

ENDNOTES Cf. the remarks made at the beginning of Section 4 below. See, for instance, Lehrer 1990, Plantinga 1990 or Sosa 1980. 3 For the exciting ethics of belief debate that took place in the nineteenth century, see the anthology edited by McCarthy (1986). 4 Wolfgang Spohn has pointed out to me that this point is fully explicit in Bonjour 1985. 5 Actually luck is not even needed. If we do not require that a belief manifests itself in an occurrent event in the believer's mind, but may reside hidden in an implicit theory of his or hers, we may assume that the beliefs of an agent are logically closed. Then any justified false belief cp gives rise to an infinite set of justified true beliefs-all disjunctions cp V cpt where cpt is any arbitrary truth. So Smith is not just lucky, but his false belief that Jones owns a Ford will automatically generate infinitely many justified true beliefs like x. 6 According to Lehrer, we sometimes believe cp for the sake of felicity or the pleasure of believing so, but we would not accept cp for these reasons. Lehrer says that there is always a potential conflict between the 'ancient system of perceptual belief' which is the 'yield of habit, instinct, and need' and the 'truth-seeking ... scientific system of acceptance'. While the former is an 'automatic input system', the latter is 'capable of ratiocination' (Lehrer 1990, pp. 113-114). In this paper, I work on the simplifYing assumption that all doxastic attitudes are 'aiming at' truth: If an agent either believes or accepts that cp, this means that he holds cp true. 7 Lehrer (1990, p. 138) apparently thinks that the two formulations are 'equivalent'. 8 Compare in particular Lehrer 1990, pp. 141-152, and 1997,28-45. 9 These operations are carried out only hypothetically, 'for the sake of argument' in fictitious test dialogues with an omniscient sceptic. In reality, the agent's state of mind remains unchanged. 10 This is the term used in Lehrer 1990; in Lehrer 1997, pp. 25-29, and Lehrer 2000, the leading part is taken by the 'evaluation system' which includes not only a person's accepted propositions (geared to truth) but also her preferred propositions (geared to merit). 11 Definition 03 on p. 148 of Lehrer 1990 actually starts as follows: '5 is justified in accepting cp on the basis of system X of 5 if and only if ... ' From definition 02 and the surrounding text, however, it is obvious that this is a misprint and the formulation given above is the intended one. 12 Some renaming of Lehrer 2000: ''ljJ is an objection to cp for 5 on X'. 13 Lehrer 2000: 'objection'ljJ to cp is answered for 5 on X'. 14 The most eminent advocate of cognitive decision theory is Isaac Levi (1967, 1984). For a critical voice, see Weintraub (1990). In Lehrer 1997, in particular pp. 30-35, the contribution of cognitive decision theory to personal justification has vanished and its role is taken over by the principle of trustworthiness, a kind of rationality principle that is geared solely to the acquisition of truth. Cognitive decision theory is still present, however, in the second edition of Theory of Knowledge (Lehrer 2000, pp. 144-148). 1

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15 Let us assume that p( 1j;) and p( ~1j;) are positive, so that conditionalizing by either 1j; or ~1j; is not beset with the problem of an ill-defined division by zero. 16 In his brief discussion of expected epistemic utilities, Lehrer shows little awareness of the fact that Ut and Uf mayor should depend on X, if reasonableness of acceptance is to be relative to the current acceptance system. Lehrer contrasts Ut( 'P) with 'P's (objective or subjective) probability and links it to 'P's truth, but not to the acceptance of other sentences. He does not say anything about Ul 17 Theories of plausibility of the kind I have in mind are offered, amongst others, by Grove (1988), Rescher (1976), Shackle (1961), and Spohn (1988). They would have to be supplemented by a qualitative decision theory. 18 The distinction between relational coherence (coherence as a relation) and systemic coherence (coherence as a property of a system) is discussed in connection with Lehrer's theory by Olsson (1999). 19 This problem for Lehrer's theory has also been treated by Olsson (1998). 20 This precept is plausible only if one assumes, as Lehrer apparently does, that the expected utility of rejecting a hypothesis is zero. An alternative idea would be to accept just those propositions 'P which have a degree of reasonableness that exceeds a contextually fixed threshold value. 21 We neglect the possibility that the removal of a false belief may tear along some true beliefs. 22 Could there be an eternal wiggling of the acceptance value of'P in response to the sceptic's challenges? Not if we neglect the possibility that a truth-conducive change can make 5 drop truths (as we decided to do in footnote 21) and if we set aside questions of infinity. In such a context, the sceptic has the means to make 5 accept the true and complete theory about the world which, of course, cannot be further improved. 23 A similar example about barns and papier-mache facsimiles originally due to Carl Ginet is discussed in Nozick 1981, pp. 174-175, and Bach 1984, pp. 40--41. 24 This argument depends on the assumption that if ~ is not part of an acceptance system, then it cannot be justified on the basis of that system. Strictly speaking, Lehrer does not make that assumption; compare Lehrer's definitions D2-D6 and especially my comment on D3 above. 25 Saying this actually steps beyond Lehrer's account, which does not provide for the possibility of knowledge expansion through the sceptic-which marks an important difference between Lehrer's concept of replacements and the usual understanding of the concept of revision. The uniqueness involved in talking about 'the one true and complete theory about the world' is of course relative to the language used, which I assume as given. 26 I neglect here, perhaps uncharitably, the fact that Lehrer's second edition uses richer 'evaluation systems' instead of the 'acceptance systems' of the first edition. The presentation of Lehrer 2000 follows that of Lehrer 1990 more closely than is warranted by its contents. While the first edition has the ultrasystem as a genuinely new and complex system, in the second edition the ultra system is nothing more than the pair consisting of the original system and the verific system. Introducing the term 'ultrasystem' for this entity seems a bit pompuous, but it is just a reflection of how the book came into being. 27 This is reminiscent of the idea that the justification for 'P does not only consist in the presence of reasons for 'P, but also in the absence of reasons against 'P. The point is given pride of place in nonmonotonic reasoning in the tradition of Doyle (1979). 28 I have mentioned an important difference between 'replacements' and 'revisions' in footnote 25: replacements substitute ~'P for some previous belief 'P, while revisions include expansions of belief sets by sentences about which there had not been any opinion before. 29 If this were true, then Lehrer would tum out to be a foundationalist (at least, a foundationalist in the sense of Chapter 3 of Rott 200 I). 30 My italics. Compare footnote lion p. 194 of Lehrer 1990: ' ... with the constraint that

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if'lj; logically entails X, which is false and also accepted, then "3 accepts that X" must also be eliminated or replaced in the same way as "3 accepts that 'Ij;" was.' (Again, my italics) I am reading the phrases "in the same way as" (in Lehrer's footnote I I) and 'just as" (in D12) as indicating that a replacement of 'Ij; by its negation should enforce a replacement of X by its negation. 31 Another fundamental idea which is not mentioned in Lehrer's account is that doxastic changes should be conservative, i.e., that they should incur only minimal changes to the previous acceptance system. On this idea, and its role in belief change theories, compare Rott 2000. 32 As Lehrer realizes very clearly, this objective question has to be linked to the subjective question of coherence in a separate step. 33 There has been an ongoing controversy over the coherentism-vs.-foundationalism issue in the belief revision literature for more than a decade, see Nebel 1989, Giirdenfors 1990, Doyle 1992, Nayak 1994, del Val 1994, del Val 1997, Hansson and Olsson 1999, Bochman 2000, Bochman 2001 and Rott 2001. Particularly influential as a mediator between epistemology and belief change was Harman (I 986).

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REFERENCES Bach, Kent. 1984. "Default Reasoning: Jumping to Conclusions and Knowing When to Think Twice." Pacific Philosophical Quarterly 65:37-58. Bochman, Alexander. 2000. "A Foundationalist View of the AGM Theory of Belief Change." Artificial Intelligence 116:237-263. ---.2001. A Logical Theory ofNon monotonic Inference and BeliefChange. Springer Verlag. Bonjour, Laurence. 1985. The Structure of Empirical Knowledge. Cambridge, Mass.: Harvard University Press. del Val, Alvaro. 1994. "On the Relation Between the Coherence and Foundations Theories of Belief Revision." AAAI'94 - Proceedings of the National Conference of the American Association on Artificial Intelligence, pp. 909-914. - - - . 1997. "Non-Monotonic Reasoning and Belief Revision: Syntactic, Semantic, Foundational, and Coherence Approaches." Journal ofApplied Non-Classical Logics 7:213-240. Doyle, Jon. 1979. "A Truth Maintenance System." Artificial Intelligence 12:231-272. - - - . 1992. "Reason Maintenance and Belief Revision: Foundations vs. Coherence Theories." In Peter Gardenfors (ed.), BeliefRevision, Cambridge University Press, Cambridge, pp.29-51. Gardenfors, Peter. 1990. "The Dynamics of Belief Systems: Foundations vs. Coherence Theories." Revue Internationale de Philosophie 44:24-46. Grove, Adam. 1988. "Two Modellings for Theory Change." Journal of Philosophical Logic 17: 157-170. Hansson, Sven 0., and Erik 1. Olsson. 1999. "Providing Foundations for Coherentism." Erkenntnis 51:243-265. Harman, Gilbert. 1973. Thought. Princeton: Princeton University Press. - - - . 1986. Change in View. Cambridge, Mass.: Bradford Books, MIT Press. Lehrer, Keith. 1990. Theory of Knowledge. London: Routledge. - - - . 1997. Self-Trust: A Study of Reason, Knowledge, and Autonomy. Oxford: Oxford University Press. - - - . 2000. Theory of Knowledge. Second, substantially revised edition. Boulder: Westview Press. Levi, Isaac. 1967. Gambling with Truth. New York: Knopf. - - - . 1984. Decisions and Revisions: Philosophical Essays on Knowledge and Value. Cambridge: Cambridge University Press. McCarthy, Gerald D. (ed.). 1986. The Ethics of BeliefDebate. Atlanta: Atlanta Scholars Press. Nayak, Abhaya C. 1994. "Foundational Belief Change." Journal ofPhilosophical Logic 23:495533. Nebel, Bernhard. 1989. "A Knowledge Level Analysis of Belief Revision." In Ronald Brachman, Hector Levesque and Ray Reiter (eds.), Proceedings of the 1st International Conference on Principles ofKnowledge Representation and Reasoning, Morgan Kaufmann, San Mateo, Cal., pp. 301-311. Nozick, Robert. 1981. Philosophical Explanations. Cambridge, Mass.: Belknap Press, Harvard University Press. Olsson, Erik J. 1998. "Competing for Acceptance: Lehrer's Rule and the Paradoxes of Justification." Theoria 64:34-54 . ..- ...~. 1999. "Cohering With." Erkenntnis 50:273-291. Plantinga, Alvin. 1990. "Justification in the 20th Century." Philosophy and Phenomenological Research 50, Supplement Vol., 45-71. Plato. 1994. Meno. In Jane M. Day (transl. and ed.), Plato's Meno in Focus, Routledge, London.

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Rescher, Nicholas. 1976. Plausible Reasoning. Amsterdam: Van Gorcum, Assen. Rott, Hans. 2000. "Two Dogmas of Belief Revision." Journal o/Philosophy 97:503-522. - - - . 200 I. Change, Choice and Inference. Oxford: Oxford University Press. Shackle, G. L. S. 1961. Decision, Order and Time in Human Aflairs. Cambridge: Cambridge University Press. Sosa, Ernest. 1980. "The Raft und the Pyramid: Coherence Versus Foundations in the Theory of Knowledge." Midwest Studies in Philosophy 5:3-25. Reprinted in Ernest Sosa, Knowledge in Perspective, Cambridge University Press, Cambridge 1991, pp. 165-191. Spohn, Wolfgang. 1988. "Ordinal Conditional Functions." In William L. Harper and Brian Skynns (eds.), Causation in Decision, Belief Change, and Statistics, Vol. II, Reidel, Dordrecht, pp. 105-134. Weintraub, Ruth. 1990. "Decision-Theoretic Epistemology." Synthese 83:159-177.

Chapter 14 SOME REMARKS ON THE DEFINITION OF LEHRER'S ULTRASYSTEM 1 Gordian Haas Universitat Konstanz

Abstract: According to the analysis of knowledge proposed by Lehrer, knowledge equals undefeated justified acceptance. Undefeated justification is then spelled out as coherence with every element of the ultrasystem, as Lehrer calls it. The question arises how this key-notion should be defined. Two definitions of the ultrasystem which have been proposed by Lehrer are investigated. An argument is presented that both definitions are flawed. A formal proof is given that a third and simpler way to define the ultrasystem is preferable.

According to the analysis of knowledge proposed by Lehrer, knowledge equals undefeated justified acceptance. Undefeated justification is then spelled out as coherence with every element of the ultrasystem, as Lehrer calls it. So, the notion of an ultrasystem is central to Lehrer's theory of knowledge. The question arises how this notion should be defined. Assuming some familiarity with Lehrer's theory, this paper is concerned with just this question. Three definitions of the ultrasystem, differing only in the additional constraint they either state or do not state, will be investigated. Let us first look at the following, relatively simple, way of defining the ultrasystem: (DefUltra) A system M is a member of the ultrasystem of Sat t if and only if either M is the acceptance system of S at t or results from eliminating one or more statements of the form, 'S accepts that q', when q is false, replacing one or more statements of the 243 E.1. Olsson (ed.), The Epistemology of Keith Lehrer, 243-252. © 2003 Kluwer Academic Publishers.

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LEHRER'S ULTRA SYSTEM form, 'S accepts that q', with a statement of the form, 'S accepts that not q' when q is false, or any combination of such eliminations and replacements in the acceptance system of Sat t.

This is not, however, the way in which Lehrer defines the ultrasystem. In his 1990 book Theory of Knowledge, he instead gives the following slightly different definition: 2

(DefUltra ') A system M is a member of the ultrasystem of S at t if and only if either M is the acceptance system of Sat t or results from eliminating one or more statements of the form, 'S accepts that q', when q is false, replacing one or more statements of the form, 'S accepts that q', with a statement of the form, 'S accepts that not q' when q is false, or any combination of such eliminations and replacements in the acceptance system of S at t with the constraint that if q logically entails r which is false and also accepted, then'S accepts that r' must also be eliminated or replaced just as 'S accepts that q' was. This definition differs from (DefUltra) only in the additional requirement that every statement r which is logically entailed by q and is also accepted and false should be treated just the way q was treated. In his 1997 book Self- Trust, Lehrer also gives basically the same definition of an ultrasystem. 3 A somewhat more informal characterization of the ultrasystem that is equivalent to the more formal definition (DefUltra') can already be found in Lehrer's 1988 paper Metaknowledge: Undefeated Justification. 4 But in Theory of Knowledge, Lehrer also describes the ultrasystem in terms of the ultra justification game, which is a heuristic to illustrate the ultrasystem: 5 She [the skeptic] may require the claimant to eliminate anything the claimant accepts that is false, and the claimant must eliminate the specified item from his acceptance system and at the same time eliminate anything he accepts that logically implies the eliminated item. Or the skeptic may require the claimant to replace anything the claimant accepts that is false with the acceptance of its denial and at the same time replace anything that logically implies the replaced item with acceptance of its denial. [italics GH]

Here Lehrer seems to favor a different definition of the ultrasystem, which again differs from (DefUltra) only with respect to the additional constraint it states:

(DefUltra' ') A system M is a member of the ultrasystem of S at t if and only if either M is the acceptance system of S at t or results from eliminating one or more statements of the form, 'S

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accepts that q', when q is false, replacing one or more statements of the form, 'S accepts that q', with a statement of the form, 'S accepts that not q' when q is false, or any combination of such eliminations and replacements in the acceptance system of S at t with the constraint that if q is logically entailed by r which is also accepted, then'S accepts that r' must also be eliminated or replaced just as'S accepts that q' was. Since (DefUltra') and (DefUltra' ') are obviously not equivalent by definition, it seems odd that Lehrer gives these two different characterizations of the ultrasystem in the same book without presenting any philosophical argument for their equivalence. Worse still, it seems to be pretty obvious that both definitions are in fact not equivalent except for some trivial cases. Although there is certainly, therefore, a serious tension between these two characterizations of the ultrasystem given by Lehrer, I shall not inquire which one could or should be regarded as the authorized one. Instead, I shall argue against both (DefUltra') and (DefUltra"). My claim is that one should adopt the most simple definition of the ultrasystem, that is (DefUltra). I will thereby argue against all the characterizations of the ultrasystem which Lehrer gave in [1], [2] and [3]. It is worth mentioning that in the second edition of his Theory of Knowledge, Lehrer gives a simplified characterization of the ultrasystem 6 that is not affected by the criticism in this paper, and to which this author is actually quite sympathetic. Also, one can understand the following argument for (DefUltra) as a partial motivation for Lehrer's new characterization of the ultrasystem. But before I will argue for (DefUltra), let us first consider the merits of (DefUltra') and (DefUltra"). A motivation can be given for both of them. Although Lehrer has not, to my knowledge, published a motivation for the introduction of the additional constraints of (DefUltra') and (DefUltra"), he has orally reported to this author that the reason for doing so has been a worry that could be called 'the problem of the creation of artificial justifications'. Let me try to explain what this means as well as I can before arguing that this worry is groundless. Let us first consider an example supporting (DefUltra) Suppose someone accepts p and also accepts P/\q, but for some reason fails to accept q. Now suppose further that p is false and hence that P/\q is also false. According to (DefUltra) there would be an element M of the ultrasystem where p, -,(p/\q) E M.7 According to the system M, one would be justified in accepting -,q since this is a logical consequence of p and -,(p/\q). Since the person initially did not have any epistemic attitude toward q or -,q, this creation of a justification for -,q seems to be artificial. A more drastic case would be one in which the person initially accepts q as well. Then, according to (De fUltra) , there would be an element M of the ultrasystem with p, q, -,(p/\q) E M. Since M is logically inconsistent, every proposition would

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be justified relative to M So, according to (DefUltra), it is possible that in some elements of the ultra system artificial justifications are created. At least, prima facie, one can conceive of a worst-case scenario in which a person originally has a faulty justification for some statement p that gives rise to Gettier-type problems and in which in every element of the ultrasystem as defined by (DefUltra), there will be created an artificial justification for p as well, so that the justification for p will remain undefeated. According to the analysis of knowledge as undefeated justified acceptance, one would therefore know that p, contrary to what an adequate definition of the ultrasystem should accomplish. The additional constraint of (DefUltra ') seems to be appropriate to avoid this unwanted effect. Considering the initial example, the system M would not be an element of the ultrasystem defined by (DefUltra') because P/\q implies p and p is false and also accepted. Therefore, the constraint of (DefUltra') would require us to form a system M, instead of M, where we replace not only P/\q by -,(p/\q) but also replace p by ---,po So we would have ---,p, -,(p/\q) E M. Now -,q is no longer deducible and therefore no artificial justification has been created. In the modified example from above, (DefUltra') would similarly require us to form a system M, instead of M, which is not inconsistent. A similar consideration can be given to motivate (DefUltra"). Suppose there is a person who accepts both p and P/\q. Suppose further that p is false and therefore P/\q is false as well. According to (DefUltra), there is an element M of the ultrasystem where p ~ M and P/\q E M Though we have eliminated p in M, p would still be justifiable in M on grounds of accepting P/\q. Again we would have some unwanted artificial justification. (DefUltra") seems to be appropriate in dealing with this case. Since p is logically entailed by P/\q and P/\q is also accepted, the constraint of (DefUltra") would require us to form a system M' instead of M, where we not only eliminate p but also eliminate P/\q. Thus on M' we no longer have an unwanted justification for p. 8 So there seems to be some quite good reasons to define the ultrasystem by (DefUltra') or (DefUltra") rather than by (DefUltra). Despite this, I will argue for (DefUltra) because I believe that the goals (DefUltra') and (DefUltra") are aiming at are already brought into effect by (DefUltra). Ifthis is true, all one would need is the more simple (DefUltra). Although the proof! want to give to support my claim is somewhat technical, the underlying idea is very simple. Therefore, it might be helpful to give a sketch of the idea first, before we turn to the detailed proof. In the foregoing examples, (DefUltra) gave rise to systems M of the ultrasystem on which too many beliefs are justified. By stating additional constraints, (DefUltra') and (DefUltra") required us to form a system M (M '), instead of M, on which these unwanted

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justifications are no longer available. But I will try to demonstrate that, in addition to M, the system M (M ') is also a member of the ultrasystem defined by (DefUltra). Since it is necessary for a justification to be undefeated not to be defeated by any member of the ultrasystem only those statements that are justified on both systems M and M (M ') will have an undefeated justification. Therefore, the unwanted justifications relative to M do not increase these justifications that will remain undefeated. The claim that an arbitrary member of the ultrasystem defined by (DefUltra') or (DefUltra") is also a member of the ultrasystem defined by (DefUltra) of course needs to be proven. I will first prove that we should prefer (DefUltra) over (DefUltra'); the proof concerning (DefUltra") will be perfectly analogous. For such a proof, we need to give a formalization of the somewhat informal definitions of the ultrasystems stated above. Obviously, a recursive approach seems to be appropriate. But first, some remarks on notation are in order: The acceptance system (of Sat t) will be denoted: A. The ultrasystem and its members (of S at t) according to (DefUltra) will be denoted: U= {MJ. M 2 ,oo.}. The ultrasystem and its members (of S at t) according to (DefUltra') will be denoted: U' = {MI " M 2',oo.}.

Def 1.1: Definition of an ultrasystem according to (DefUltra): 1.AEU. 2. If M E U and q E A is false then M-q := M\{q} E U. (elimination) 3. If ME Uand q E A is false then M*q:= (M\{q}) u {.q} E U.

(replacement) 4. Uhas no other elements than those mentioned by 1. - 3.

Def 1.2: Definition of an ultra system according to (DefUltra'): 1. A E U'. 2. If ME U' and q E A is false then M-' q := M \ {r IrE A and q f- rand r is false} E U'. (elimination) 3. If ME U' and q E A is false then M*' q := [M\ {r IrE A and q f- rand r is false}] u {r I .r E A and q f- .r and .r is false} E U'. (replacement) 4. U' has no other elements than those mentioned by 1. - 3.

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The reader will notice that these formalizations are adequate counterparts of the more informal definitions (DetUltra) and (DetUltra'). To be able to prove some properties of all members of the set U' by induction, we need to define the degree of a member of U'. We will do this again recursively. Def 2: Definition of the degree of M 1. degree(A) = O. 2. degree(M-'q) = degree(M) + l. 3. degree(M*' q) = degree(M) + l.

E

U':

Now we have got all the clues together to prove: Lemma 1: U'S;;; U. Proof: We have to show that if M E U' then M E U. So let us suppose that M E U'. We will show by induction on the degree of Mthat M E U. degree(M) = 0: It follows M = A and therefore M E U (by clause 1 of Def 1.1). degree(M) = n: o.k. degree(M) = n+l: Case 1: M = N-' q for some N, q where N E U', degree(N) = n, q E A, q is false. Because N E U' and degree(N) = n, we have by the induction hypothesis that N E U. We have to show that M= N\ {r IrE A and q I- rand r is false} is also an element of U. Let {r IrE A and q I- rand r is false} = {rl> .. .,rk}.9 We can then rewrite Mas:

M= (... «M{rJ})\{r2})\... )\{rk}' Note further that all the rJ, .. .,rk are trivially elements of A that are false. Because of this, and because N E U, we have by clause 2 of Def 1.1 that M{rJ} E U. By the

same reasoning,

we

have

(M{rd)\{r2} E U etc.

Therefore we have ME U. Case 2: M = N*' q for some N, q where N E U', degree(N)

=

n,

q E A, q is false. Because N E U' and degree(N) = n, we have by the induction hypothesis that N E U. We have to show that M is also an element of U where M = [N \ {r IrE A and q I- rand r is false} ]

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U {r I-,r E A and q f- -,r and -,r is false}. Let {r IrE A and q f- rand r is false} = {rl> .. .,rk} 10, we

then have {r I -,r E A and q f- -,r and -,r is false} {-,rl> ... ,-,rk}' We can then rewrite Mas: M = (( ... ((M{rj} )u{-,rj} )\u ... )\{rk} )u{-,rk}' Note further that all the rj , ... h are trivially elements of =

A that are false. Because of this, and because N E U, we

have by clause 3 of Def1.l that (M{rj})u{-,rj} E U. By the same reasoning, we have (((M{rd)u{---,rd)\{r2})u{-,r2} E U etc. Therefore we have ME U.

o

Now we need to introduce some new notations. If M is an element of the ultrasystem then Js(.M) shall denote the set of all beliefs justified on M. That is: Js(.M)

=

{p Ip coheres with M}.

If U is an ultrasystem, then Js(U) shall denote the set of beliefs that are justified on all members of U. That is: If U = Js(U)

U{Mi} then

=

{p Ip coheres with every Mi E U} or more precise:

Js(U) = nJS(Mi). iEJ

For ultrasystems U', according to (DefUltra') and their elements M Js(M') and Js(U') should be understood in a perfectly analogous way. Lemma 2: If U j ~ U2, then JS(U j );;2 Js(U2). Proof: Since U1 ~ U2 , we can assume without loss of generality that for some index sets I, J we have: Ul =

U{Mi} and U2 = U{Mi}.

iEJ

iEJUJ

250

LEHRER'S ULTRASYSTEM We then have: Js(U2) =

n [n JS(Mi) =

iE/VJ

JS(Mi)] n

= Js(UI) n[nJS(Mi)] IEJ

[n

JS(Mi)] =

iEJ

iE/

~ Js(UI) o

Theorem 1: Js(U) ~ Js(U'). Proof: By specializing Lemma 2 on UI If U' ~ Uthen Js(U) ~ Js(U'). Since by Lemma 1 we have U' Js(U) ~ Js(U').

~

=

U' and U2 = U we get:

U, we get by modus ponens:

o

What is the upshot of all this? The interpretation of Theorem 1 is this: all justifications that remain undefeated if one defines the ultrasystem by (DefUltra) also remain undefeated if one defines it by (DefUltra'). The worry that (DefUltra) could create unwanted justifications, thereby leaving too many justifications undefeated, was without good reason. Every justification we wanted to exclude by the additional constraint of (DefUltra') is already excluded by (DefUltra)! Therefore, if the only reason for introducing the additional constraint of (DefUltra') is to avoid unwanted justifications, then we can just abandon this constraint from our definition of an ultrasystem. That is, we should adopt (DefUltra) because we are benefiting from this in three ways: (1) We do not have to introduce a constraint for which the motivation is somewhat controversial; (2) We have exactly what we intended to get by introducing the additional constraint; (3) We can even simplify the theory by so doing! It remains to be demonstrated that (DefUltra) is also preferable over (DefUltra"). If we give a recursive definition of U" = {MI ", M2", ... }, and the degree of its members that is analogous to the one given for U and U', then we are able to prove:

Lemma 3: U"

~

U.

Since the proof for this is also perfectly analogous to the one of Lemma 1, it would be unforgivable pedantry to present it in detail. But it should be noted that every element of the set {r IrE A and r f- q} is trivially an element of A

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that is false if q is false. Therefore, all elements of this set fulfill the requirements of clause 2. and 3. of Def 1.1. This is the reason why we can treat the case of (DefUltra' ') parallel to the one of (DefUltra') in the induction step. Using Lemma 2 again, we can immediately infer from Lemma 3:

Theorem 2: Js(U)

~

Js(U").

This Theorem should obviously be interpreted as analogous to Theorem 1, and leads us to the conclusion that we should prefer the simple definition (DefUltra) not only over (DefUltra') but also over (DefUltra' ').

ENDNOTES 1 An earlier draft of this paper has been presented to Keith Lehrer. I am indebted to him for his helpful comments. It is worth mentioning that Lehrer welcomed the proposal of this paper. An earlier version of this paper was also read at the Lehrer-workshop in Konstanz in 2000. I wish to express my indebtedness to the participants of the workshop for the helpful discussion, in particular to Wolfgang Spohn and Erik Olsson who also read a first version of the paper. 2 See [2], p. 149 and also p. 194 (n.!l) where Lehrer defines the ultrasystem exactly as in (DefUltra') [where I added the italics]. 3 See [3], p. 44. There are some minor differences between the formulations in [2] and [3] including the usage of the term 'evaluation system' instead of 'acceptance system' but the crucial point is the same. In both definitions of the ultrasystem Lehrer states the additional constraint of (DefUltra'). 4 See [1], p. 343. 5 See [2], p. 14l. 6 See [4], p. 171, definition D8. 7 Here and further expressions like 'p EO M' are to be understood as shorthand for "S accepts that p' EO M'. This notation simplifies our formulas considerably. 8 This case parallels the case of a contraction discussed in the theory of belief revision. If one contracts ones belief set ('" acceptance system) by p, one not only has to eliminate p but one also has to take care that p is no longer deducible from the belief set. Therefore everything that entails p and is also an element of the belief set must be eliminated too just as (DefUltra") requires. 9 In order to write {r I r EO A and q f- rand r is false} as {rl' .. .,rk} we made the assumption that

{r I r EO A and q f- rand r is false} contains only finitely many elements. This assumption has been made to simplify the proof. But note that this assumption is not essential. If one abandons this assumption one has to make a sub-induction on the number of elements in {r I r EO A and q I- rand r is false}, in addition to the main induction on degree(M). 10 Cf. last footnote.

REFERENCES: [1] Lehrer, K.: Metaknowledge: Undefeated Justification. In: Synthese 74 (1988). Reprinted in his: Metamind. New York 1990.

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[2] Lehrer, K.: Theory of Knowledge. 1st ed. Boulder 1990. [3] Lehrer, K.: Self-Trust. A Study of Reason, Knowledge, and Autonomy. Oxford 1997. [4] Lehrer, K.: Theory of Knowledge. 2 nd ed. Boulder 2000.

Chapter 15 ON LEHRER'S SOLUTION TO THE GETTlER PROBLEM! Jacob Rosenthal University of Bonn

The classical analysis of the concept of knowledge is as follows. Let Sbe an epistemic subject and p a proposition. S knows that p if and only if (1) p is true, (2) S believes that p, and (3) S is justified in believing that p.

It seems clear that the conditions (1 )-(3) are indeed necessary for knowledge.

But as some well-known examples (by Edmund Gettier, among others) show, the stated conditions are not sufficient. The problem is that S's justification for his belief that p may involve a false belief in an essential way. In such cases we typically do not speak of knowledge, although the stated conditions are fulfilled. So the task is to discover a fourth condition such that (1 )-(4) together are necessary and sufficient for knowledge. The following is Keith Lehrer's solution of the problem. 2 Take the set of all beliefs of S. This is called the acceptance system of S. Condition (3) can be read as stating that the belief that p is justified relative to this system, or, as Lehrer says, on the basis of this system. Now, what Lehrer demands in addition to justification relative to the acceptance system is justification relative to certain modifications of it. Namely, if the acceptance system contains false beliefs, and some of them are deleted from the system or even replaced by the corresponding true beliefto the contrary, the belief that p must still be justified relative to this new system to count as knowledge. 253 E.J. Olsson (ed.), The Epistemology of Keith Lehrer, 253-259. © 2003 Kluwer Academic Publishers.

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More exactly: Suppose the acceptance system ofS contains n false beliefs. Now you decide for each of them independently ifit is to be (a) deleted from the system, (b) replaced by the corresponding true belief, or (c) left untouched. In this way you can obviously get 3n modifications of the acceptance system (one of which is the acceptance system itself). S's belief that p is knowledge if and only if it is justified relative to each of these 3n belief systems. The idea behind this is that, to count as knowledge, S's belief that p must survive corrections in the system of all beliefs of S. Make any corrections you want, either weak (delete a false belief) or strong (replace a false belief by the corresponding true one }-you always get a system relative to which the belief that p is still justified. Then, and only then, S's belief that p is knowledge. This proposal for solving the Gettier problem has great aesthetic appeal, which is, however, somewhat diminished by a complication introduced by Lehrer I didn't mention in order to keep things simple. Namely, the deletion or replacement of false beliefs in the acceptance system is not entirely unconstrained. If q and r are false propositions, and both are believed by S, and q logically entails r, then, if you delete the belief that q from the acceptance system, you must also delete the belief that r, and if you replace the belief that q by the belief that not-q, you must also replace the belief that r by the belief that not-r. So, your decisions what to do with the false beliefs are not totally free and independent from each other. You have to respect relations oflogical entailment in the indicated way. But this constraint is the only one and, having mentioned it, the presentation of Lehrer's account of knowledge is complete. 3 I think that Lehrer's conception of knowledge is too demanding. Take the following example: A reliable person has told me that the senate of my university has elected Cohen for rector, which is indeed the case. So I know that Cohen is rector. Most of what we know we get to know in more or less this way. Now I remember a clause in the constitution of the university to the effect that the rector is also the chairman of the Research Committee. I conclude that Cohen is chairman of the Research Committee. But this is, in fact, wrong. The senate of the university has, on the very same meeting, changed the constitution and separated the positions. Cohen was only prepared to become rector if he need not also be chairman of the Research Committee. My source of information has told me nothing about this (nor should he have). This has the effect that if I got to know that Cohen was definitely not the chairman of the committee, I would also doubt his being rector and no longer believe it. There are two false beliefs in my acceptance system: first, the belief that the constitution of the university still contains the rule that the rector is also the chairman of the Research Committee, and second, the belief that Cohen is chairman of this committee. If the second belief is replaced by the corresponding true belief, while the first false belief is left unchanged, the belief that Cohen is rector is no longer justified, i.e., not justified on the basis of this modification of the

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acceptance system. (At least you can construe the case in this way.) So Lehrer's criterion is not fulfilled, and my opinion that Cohen is rector would not count as knowledge. This is clearly counterintuitive. I know that Cohen is rector. All I have done is to draw from this true proposition as one premiss and a false proposition as second premiss a false conclusion. Normally such an act should not destroy the knowledge status of the true belief. But Lehrer's condition is such that this is regularly the case. I think that Lehrer's idea to consider modifications of the acceptance system of Sin order to decide whether S's beliefthatp is knowledge is the right idea, but his condition is too strong. It is sufficient, but not necessary for knowledge. The problem in the example arises because in modifying the acceptance system, you are allowed to correct just some of the false beliefs, while leaving others untouched. In my opinion, Lehrer should have said the following: the modifications of the acceptance system of S relative to which the belief that p must be justified must not contain any false beliefs any longer. So, ifthere are n false beliefs in the acceptance system, you have to decide for each of them whether it is deleted from the system or replaced by its true counterpart. There are 2n possibilities to do so. A true belief of S is knowledge if and only if it is justified relative to the acceptance system of S and relative to these 2n corrections of it. I think this is a better proposal for solving the Gettier problem. (And the above-mentioned constraint is now in any case superfluous, because the modified systems contain only true beliefs.) Is it really necessary to take into account so many different belief systems? I don't really know, but with criteria of the Lehrer type it is definitely not enough to consider just one modification of the acceptance system of S. It would be much easier, of course, if you could say that S's true belief was knowledge iff it was justified, first, relative to S's acceptance system, and second, relative to a certain correction of it. But conditions ofthis type turn out too weak. I consider the two most natural proposals along this line. (a) S's true belief that p is knowledge if and only if it is justified relative to the acceptance system of S and relative to the system that results from deleting all false beliefs from the acceptance system. That this condition is not sufficient for knowledge is shown by an example that comes from Bertrand Russel1. 4 A pedestrian is walking down the street wondering what time it is. He looks at a clock on a church tower which shows ten minutes past three, from which fact he concludes that it is ten minutes past three. And indeed this is true. What the pedestrian does not realize is that the hands of the clock do not move. The clock has stopped a long time ago and the pedestrian just happens to be looking at it at a moment when it shows the right time. So, intuitively, the pedestrian does not know that it is ten minutes

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past three, but has just happened to acquire a true belief to this effect. This belief is justified on the basis of the pedestrian's acceptance system. The acceptance system contains the false belief that the clock is moving and working in the usual reliable manner. But this false belief is no indispensable part of a justification for the pedestrian's opinion about the time, and therefore his opinion is still justified if the false beliefis deleted from the acceptance system. Ajustification might run as follows: "This is a clock. It shows ten minutes past three. Most clocks work properly most of the time and therefore show the right time most of the time. So I conclude that this clock shows the right time right now and believe that it is ten minutes past three." The false belief that this clock works properly is not involved in this reasoning, and so this reasoning is not blocked by merely deleting the false belief from the acceptance system. Therefore the stated criterion is fulfilled and gives the false result that the pedestrian's belief about the time is knowledge. The remedy seems obvious. If you not only delete the false belief that this clock works properly from the acceptance system, but replace it with the true belief that this clock does not work properly, then the justification just sketched is blocked or, as Lehrer says, defeated. So, what about the following condition? (b) S's true belief that p is knowledge if and only if it is justified relative to the acceptance system of S and relative to the system that results from replacing in the acceptance system all false beliefs by their true counterparts. That this condition also fails can be shown by an example invented by Roderick Chisholm. 5 A wanderer reaches a meadow on which there are two animals. The first one looks like a sheep, but in fact it is not: it is a Bedlington Terrier. Dogs of that race are easily confused with sheep. The wanderer does not know about this and considers the first animal to be a sheep. He therefore comes to the conviction that there is a sheep on the meadow. And this is true, because the second animal is a sheep, although it does not look like one at all. Now, the wanderer has the true belief that there is a sheep on the meadow. This belief is justified by the fact that there is an animal looking like a sheep, namely, the first one. There are two false beliefs in the wanderer's acceptance system: that the first animal is a sheep, and that the second animal is not. Ifboth false beliefs are replaced by their true counterparts the belief that there is a sheep on the meadow is still justified. So the wanderer's conviction would count as knowledge, which is clearly counterintuitive. Let's look at this example more closely. Why does the proposed criterion fail? The problem is that the wanderer's belief is justified before and after the false beliefs in his acceptance system are replaced by their respective true counterparts. But how can that be? Isn't the wanderer's justification for his true belief, namely, that the first animal is (or looks like) a sheep, defeated by the

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correction of his acceptance system? Indeed it is, but the correction gives the wanderer another way to justify his belief, namely, that the second animal is a sheep, although it does not look like one. So the conviction that there is a sheep on the meadow is justified before and after the correction of the wanderer's acceptance system. But it is justified in two different ways. Now we have hit on the reason why the original and the modified Lehrer criterion have to take into account so many different modifications of the acceptance system of the subject S. If you consider just one or a few of these modifications, one can always dream up examples where S's original justification for his true belief is defeated, but where the defeating modifications open up other ways to justify the belief that p. In such cases we typically do not count S's belief as knowledge. It is merely a lucky coincidence that the subject, although his original justification is defeated, has now other, new ways to justify the true belief in question. In order to make such examples impossible, one has to put up criteria which refer to a multitude of corrections of the acceptance system, in a sense, to all possible corrections of it. But obviously there is another possibility to deal with the problem such examples pose. You just have to demand that the subject's original justification is preserved when the acceptance system is corrected. 6 Instead of demanding that S's belief that p be justified relative to very many different belief systems, you demand that the belief is justified relative to just a few, but always in the same way. I propose the following condition as a solution to the Gettier problem along the indicated lines: S's true belief that p is knowledge if and only if among the reasons S has for his belief that p there are reasons r l , r z, ... ,rm with the following properties: a) b) c)

r l , r z, ... , rm are true, together they are sufficient to justify the belief that p relative to S's acceptance system, together they are sufficient to justify the belief that p relative to the system that results when in S's acceptance system all false beliefs are replaced with their true counterparts.

In short, a true belief of a subject is knowledge iffthe subject has ajustification for the belief that remains a justification when in the subject's acceptance system all false beliefs are replaced with the corresponding true ones. It is not required that every justification of the subject has this property - a belief may be justified in many different ways, and it is no harm when some of them are faulty. But at least one possible justification, a justification that the subj ect could use if asked, must be able to survive the mentioned strong correction of the

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acceptance system. Then, and only then, is the true belief knowledge. In comparison with Lehrer-type proposals, this proposal for solving the Gettier problem has the advantage of involving just two belief systems, whereas the former have the advantage of using merely the concept of a justified belief (relative to a system of beliefs) and not the more demanding concept of (sufficient) reasons for a belief (relative to a system of beliefs). So we have arrived at two proposals for solving the Gettier problem: first, the modified Lehrer proposal, and second, the one just mentioned. I am not sure whether they are equivalent. But they could both be satisfactory solutions to the Gettier problem and yet not be equivalent, as long as they agree in all clear cases. There are borderline cases of belief in which one does not know whether to call the belief in question knowledge, because the intuitions are unclear or divided. No proposed criterion can be dismissed just because it decides a borderline case in this or that way. As long as it gets the clear cases right, it may count as a solution of the Gettier problem, and so there may be many nonequivalent solutions. But I am afraid that sooner or later a clear example will come up for which the two proposals considered here fail, as was the fate of so many of their predecessors.

ENDNOTES I These considerations were first presented on a workshop on Keith Lehrer's epistemology and related topics, held at the University of Constance on June 16th , 2000. I am grateful to Keith Lehrer for a discussion of these topics, to Wolfgang Spohn for several valuable remarks, and to Christopher von Bi1Iow for improving my English. 2The presentation follows Lehrer's Theory o/Knowledge, Boulder 1990. His account has remained essentially the same since the middle of the 80s and can be said to be the most prominent internalistic proposal to solve the Gettier problem. (Compare also his book Self-Trust, Oxford 1997.) But recently Lehrer has changed his mind, as can be seen in the second edition of Theory o/Knowledge, Boulder 2000. His new proposal is similar to proposal (a), discussed below, which is also unsatisfactory. 3 Actually, I have some difficulties with this constraint. I would expect it to be the other way round. If q logically entails r, and you delete the beliefthat r from the acceptance system, you should also delete the beliefthat q, because otherwise the beliefthat r remains in the system in an implicit way. After all, r is logically entailed by q. The same holds for the case of replacement. So the constraint should be that in case you delete or replace the belief that r you must do the same with the belief that q. But that is not important here, because the constraint, whatever it is, will play no role in what follows. A constraint ofthis type is a half-hearted step into the direction ofthe AGM-theory of belief revision (see Peter Gardenfors: Knowledge in Flux, Cambridge (Mass.) 1988), and therefore unsatisfactory anyway. Either you should accept the whole AGM-apparatus (or something similar), or you should try to make do without any proviso of this form. 4 Bertrand Russell: Human Knowledge. Its Scope and Limits, London 1948, p. 170. 5 Roderick Chisholm: Theory o/Knowledge, New Jersey 1966,21977, p. 105.

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6 As Volker Halbach pointed out to me, John Pollock makes a similar proposal in the Appendix of his book Contemporary Theories of Knowledge, Totowa 1986. The difference is that Pollock believes (mistakenly, I think) that there are examples ofthe Gettier type in which the subject does not believe anything false. So he does not speak of a correction ofthe subject's acceptance system, but of adding truths to it. (In the clock example the subject does believe something false: namely, that the clock is working properly. This false belief is no indispensable part of the subject's justification for his opinion about the time, but it is nevertheless connected with this opinion. That the subject's justification for his belief does not, or need not, include any false beliefs in Gettier problem examples does not mean that there is no false belief involved at all.)

SKEPTICISM

Chapter 16 SKEPTICISM, JUSTIFICATION AND THE TRUSTWORTHINESS ARGUMENT John W. Bender Ohio University, Athens

We must, therefore, in every reasoning form a new judgement, as a check or controul on our first judgement or belief; and must enlarge our view to comprehend a kind of history of all the instances, wherein our understanding has deceived us, compar'd with those, wherein its testimony was just and true. Having thus found in every probability, beside the original uncertainty inherent in the subject, a new uncertainty deriv'd from the weakness of that faculty, which judges, and having adjusted these two together, we are obliged by our reason to add a new doubt deriv'd from the possibility of error in the estimation we make of the truth and fidelity of our faculties. When I reflect on the natural fallibility of my judgment, I have less confidence in my opinions, than when I only consider the objects concerning which I reason; and when I proceed still farther, to turn the scrutiny against every successive estimation I make of my faculties, all the rules of logic require a continual diminution, and at last a total extinction of the belief and evidence. -David Hume A Treatise of Human Nature, Book I

I.

BASIC SUSPICIONS

Let's begin with some old Lehrerian themes that continue to be central to the latest version of his theory of knowledge. I Epistemic justification is a matter 263 E.1. Olsson (ed.), The Epistemology of Keith Lehrer, 263-280. © 2003 Kluwer Academic Publishers.

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of coherence for Lehrer, and knowledge is a matter of undefeated justification. Personal justification in accepting a proposition, p, is a matter of whether accepting p coheres with one's personal evaluation system, i.e., whether the evaluation system of the person implies that it is more reasonable to accept that p than to accept any objection that a critic might raise to p (Lehrer [2000a], 130132).2 Knowledge requires that these objections continue to be met even when one's evaluation system is purged of whatever false acceptances might be lending their support to one's acceptance of p. Many such objections are skeptical in nature. In fact, it would not be an unfair characterization of Lehrer' s complex concept of undefeated justification to say that it is ultimately a matter of our ability (or the capability of our evaluation system) to answer skeptical questions of various sorts. The theory envisages two "games" in which a claimant asserts what he thinks he knows, and a critic puts forth an objection to the claim. The first game tests for coherence of the claim to the personal evaluation system of the claimant, which includes all of the acceptances, true or false, that the claimant holds, given his goal of accepting truths and avoiding falsehoods. The second game, the "uitrajustification game," whose outcome indicates whether the claimant's personal justification is "undefeated" and hence whether he knows the target proposition, p, allows the critic to call for the elimination of anything false that the claimant is offering in defense of the skeptical critic's objections. It is surprisingly incongruous, then, that a theory whose structure appears so concerned with skeptical objections should, in fact, be guilty of skirting and obfuscating when it comes to the skeptic's main concern. Or so I will argue. I take the skeptic's central query to be something neo-Humean like this: "Of course you believe that you are justified in accepting many of the things you do about the world around you, but are you really, and philosophically-speaking, justified? Do you truly know what you think you know?" So, at the heart of things, the skeptic challenges our claims to be epistemically justified, and thereby, challenges our claims to know. I want to suggest that, for all its references to the skeptic, Lehrer's theory is in danger of doing end-runs around her because the two games the theory plays with the skeptic or critic are aimed respectively at internal coherence, which may be too weak a notion to establish that a belief is really justified, and at undefeatedjustification or uitrajustification, which is really about making sure that our claims to knowledge do not depend upon error and falsehood. But the skeptic can jovially admit that most of us have an internally (reasonably) coherent system of beliefs, and also that skeptical possibilities do not have to be true to perform their philosophical function and therefore, conversely, our everyday beliefs do not have to be false to be unjustified. So can the fact that it is claimed that the skeptical critic loses the two justification games really constitute a satisfying rejoinder to skepticism? Lehrer

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admits he cannot prove the skeptic wrong, but he does think that he has a convincing response to her and argues that ultimately we not only have knowledge but that we can (and must, since discursive knowledge is metaknowledge) know that we know (Lehrer [2000a), 205, 229)· His desire to establish this makes his recent discussions return to the skeptic again and again, as ifhe senses the inherent weakness of the theory's two games to really answer skepticism. The "keystone" of this effort is the concept of self-trust. And this keystone is put into place in our defenses against skepticism by the deployment of an argument Lehrer labels the "trustworthiness argument." The trustworthiness argument is touted and alleged to have the epistemic ability to loop our justification back on itself, guaranteeing coherence and saving us from the surd beliefs of foundational ism and the infinite regress of reasons which threatens if there is no loop back (Lehrer [2000b), 643). Lehrer now apparently admits that coherence within an acceptance system that fails to contain an acceptance that one is trustworthy in what one accepts will not be able to be elaborated in any way that will yield knowledge, or at least, discursive knowledge (Lehrer [2000b), 638.) This paper will examine the trustworthiness argument and Lehrer's more wide-ranging discussion of skepticism and conclude that the argument is impotent and the discussion ultimately unsatisfying. Although Hume's objection is, as stated, a type of infinite regress argument, its spirit still applies to Lehrer's theory: there is a serious doubt whether the "new judgement" of trustworthiness is, in fact, sufficiently justified to support our claims of knowledge.

2.

PERSONAL JUSTIFICATION AND THE FOUNDATIONALIST'S / SKEPTIC'S OBJECTION To be personally justified in accepting that one sees, remembers, or introspects something, one must, therefore, accept that these are trustworthy sources of information of the truth ... (Lehrer [2000a], 165). It is not enough that one accept something for it to be more reasonable than the objections to it on the basis of one's evaluation system. One must have some information that such acceptance is a trustworthy guide to the truth. (Lehrer [2000a], 137).

As I already intimated, there is a question whether internal coherence in an individual's personal evaluation system constitutes any degree of epistemic

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justification. But I do not want to enter a general and probably useless verbal discussion about the use of 'justification.' However, there is a related substantive objection that foundationalists have urged against coherentists, and which is one that any good skeptic would urge as well. Coherence with a background system of beliefs will justify a target belief only if the background beliefs themselves are justified. But a personal evaluation system contains all acceptances the person holds (with the objective of accepting somethingjust in case it is true); it is not a system of justified beliefs alone. So the skeptical question is, "Are we really justified in accepting those other things we need to accept if we are to be able to meet a critic's objections?" More clearly now than previously, Lehrer admits the force of this line of argument. His answer, given in the passages above, is that personal evaluation systems, if they are ultimately to provide us with discursive knowledge, must contain meta-acceptances of the form, "My acceptance that p is a trustworthy guide to truth." It is easy to see the necessity of these acceptances in the justification game. For example, if, on the basis of taste, I accept that the wine I am drinking is a Bordeaux, I must be able to meet (answer or neutralize) objections such as, "You have no ability to distinguish Bordeaux from Californian or Italian Cabernet," or "People often confuse California Cabernet and Bordeaux." And, intuitively, it seems correct that unless I believe that I can trust my taste in these types of matters, I will not be justified in accepting that this wine is a Bordeaux. But the obvious problem is that the necessary meta-acceptance is now a member of the evaluation system, and therefore subject to the same doubt that it itself may not be justified. Lehrer deploys two responses to this latest doubt. In both Lehrer [2000a] and [2000b] a straightforward inductive argument from successful past acceptances of the same or similar sort is thought to support the meta-acceptance that my acceptance of p is trustworthy. Although it seems to me that this is the crucial and natural argument, there is little more than a mention of it in Lehrer's discussions. (Cf. [2000a], 138, 142 and [2000b], 642f.) His real interest seems to lie with a different kind of argument, based upon an even more fundamental principle of self-trust: I may accept that my faculties, perception, memory, reasoning, and so forth are trustworthy guides to truth in circumstances of the sort that I find myself in when I accept what I do. I must accept, moreover, that I am trustworthy as well: that when I accept something, that is a good enough reason for thinking it to be true, so that it is reasonable for me to accept it ([2000a], l38).

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Hence, an evaluation system that ultimately supports discursive knowledge requires acceptance of "one special principle of an evaluation system" ([2000a], 138), viz., Principle T: T: I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true ([2000a], 138). Acceptance of(T) explains why my particular acceptances are trustworthy and hence why it is reasonable for me to accept them. Lehrer says: [I]f I accept that I am trustworthy in this way, then my accepting something will be a reason for me to accept it ([2000a], 138). We can wonder, at this point, how accepting something can be a reason for accepting it, since nothing can be a reason for itself. Apparently, Lehrer is suggesting that the fact of my acceptance of p, given that I also accept (T), constitutes a reason or evidence supporting the truth ofp. But it seems clear that such a line of reasoning has credence only if the acceptance of (T) is justified. We must not lose sight of this fact as we turn to Lehrer's trustworthiness argument and the work it is given to do.

3.

THE TRUSTWORTHINESS ARGUMENT

Principle (T) acts as a guarantor of my acceptance of the trustworthiness of my target acceptance that p. In other words, when (T) is included in my evaluation system, I am able to reason from my acceptance of p to the reasonableness of that acceptance. This is the trustworthiness argument. Lehrer formulates the reasoning in the following way: (T) I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true. I accept that p with the objective of accepting that p just in case it is true. Therefore, I am trustworthy in accepting that p with the objective of accepting that p just in case it is true. Therefore, I am reasonable in accepting that p with the objective of accepting that p just in case it is true ( [2000a], 139).

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A few clarificatory observations about the trustworthiness argument are necessary. (T) is meant to be understood not as a universal deductive principle, but as an expression of a fallibilistic disposition or capacity to be trustworthy. Also, and relatedly, the inference from (T) to the conclusion that I am trustworthy in accepting that p is meant as an inductive inference, not a deduction. Third, and most importantly, it should be noted that the conclusion of the argument is not equivalent to the conclusion that I am personally justified in accepting that p. This is because personal justification requires that all objections that the critic might present to the conclusion of argument must be answered or neutralized (cf. [2000a], 143). It must be more reasonable for me to accept the conclusion than to accept any objection against it for me to be personally justified in accepting the conclusion. Now, the trustworthiness argument is a bit of reasoning for the conclusion that I am reasonable in accepting that p. How justified the conclusion of this reasoning is for me depends on how justified I am in accepting the argument's premises, especially (T). As we saw from the passage quoted in the opening of section II above, Lehrer himself believes that mere acceptance of something does not suffice to make it more reasonable than objections to it on the basis of one's evaluation system (137). Clearly, the skeptical critic will object that (T) is not more reasonable to accept than, e.g., the hypothesis that we are deceived in thinking we are trustworthy. Hence, the conclusion of the trustworthiness argument would be seen as unjustified. This objection must be adequately dealt with, and the trustworthiness argument does nothing in and of itself to provide a response. So it would be a mistake to think that the trustworthiness argument constitutes a personally justifying argument for the reasonableness of what we accept. If (T) is now an important member of my evaluation system, then, just as we saw earlier that my meta-acceptance that my acceptance that p is trustworthy, (T) also must bejustifiedly accepted if the trustworthiness argument is to successfully perform its intended justificatory function. But what is the argument that my acceptance of (T) is justified?

4.

THE LOOP OF TRUSTWORTHINESS

Although inductive support for (T) is again mentioned (142), Lehrer focuses, as he did in his book, Self Trust, (Lehrer [1996]), on a different, "more direct" (2000a,142) argument to the effect that the trustworthiness argument exemplarizes itself (Cf. [2000b], 641-2), and, in a sense, therefore, is selfjustifying. The idea is that the trustworthiness argument can be applied to (T) itself, by taking (T) as the value for 'p' in the argument. Lehrer says:

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If a person accepts (T), then her acceptance of (T) itself will have the result that it is reasonable for her to accept that (T) by an application of the trustworthiness argument to (T) itself as the target acceptance p. The principle applies to itself. It yields the results that ifshe accepts (T) with the objective of accepting it just in case it is true, then she is trustworthy in accepting it, and by the trustworthiness argument, to the conclusion that she is reasonable in accepting it (Lehrer [2000a], 142). Something quite peculiar is going on here. If the trustworthiness argument is a bit of reasoning that the subject puts forward for justificatory purposes, then each premise of the argument is an expression of something the subject accepts. But, then, ifI accept the first premise (T), the second premise adds nothing to the argument. So it is supposed to follow from the fact that I accept that I am trustworthy, that I am trustworthy in accepting that I am trustworthy, and hence reasonable in accepting that I am trustworthy in what I accept. But how can it follow from the fact that I accept that I am trustworthy, that it is reasonable that I am trustworthy? When (T) replaces p in the trustworthiness argument, the conclusion is that I am reasonable in accepting the trustworthiness principle. But this conclusion is only justified for me to the degree that the premises are justified. Hence, I must be antecedently justified in believing premise (T), and therefore, I must already be reasonable in accepting (T). Consequently, the trustworthiness argument is moot by presupposing its own conclusion. I see no virtue in the supposed "virtuous loop of reason" (142). Another way of seeing that the trustworthiness argument does not provide a looping justification for principle (T) is to notice that any unjustified (T*) might be offered as the value of p. Imagine that I accept every statement occurring in the Bible as true, and that I think this while I am motivated to believe things just in case they are true. Let (T*) be the principle that I am trustworthy in my Biblical acceptances. The trustworthiness argument, then runs as follows: T: I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true.

Therefore, I am trustworthy in accepting (T*): I am trustworthy in my Biblical acceptances, with the objective of accepting this just in case it is true.

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JUSTIFICA TION AND TRUSTWORTHINESS Therefore, I am reasonable in accepting (T*): I am trustworthy in my Biblical acceptances, with the objective of accepting this just in case it is true.

If acceptance of (T) has the power to make (T) reasonable, it has the power to make (T*) reasonable. But, that (T*) is reasonable on the basis of the trustworthiness argument is completely absurd. The mere acceptance of (T), even assuming (T)'s truth, has no inherent justificatory power, and no amount of "looping" through the trustworthiness argument can generate what is not there.

5.

PERSONAL JUSTIFICATION AND THE TRUSTWORTHINESS ARGUMENT

If the virtuous loop of reason cannot be relied upon to support the acceptance that I am reasonable in accepting that p (whether p is principle (T) or is some other acceptance), it becomes a question whether I can go on to be personally justified in accepting that p. If the trustworthiness argument fails to establish that I am reasonable in accepting (T) then the conclusion of the trustworthiness argument (viz., that it is reasonable for me to accept that p) seems open to the critic's objection that this conclusion is based upon a premise (viz., (T)) which is not justified since it is not more reasonable to accept than the skeptical hypothesis that I am systematically deceived, say, by an all-powerful demon rendering all my first-order acceptances false. Lehrer's answer to this is that I do accept that it is more reasonable for me to accept that p than that I am generally deceived. ([2000a], 133). This may well be true, but we have now seen that the trustworthiness argument does nothing to establish that it is more reasonable to accept this. I must accept, apparently on inductive grounds, that my evidence for p is trustworthy and renders it very improbable that I am deceived (134). I may, in fact, accept this, and, therefore, there is little argument that I am not personally justified in accepting p. But we are still far from knowing anything against the skeptic's objections.

6.

A SECOND CIRCLE?

I have charged the trustworthiness argument with circularity. Another, equally pernicious, circle seems to be lurking in this discussion. Lehrer says that, "my reasonableness is explained in the argument by my trustworthiness" (139). And, of course, this is Lehrer's whole intent: to support claims of what

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it is reasonable to accept-claims that can be used in the justification games-by relying on one's acceptance that one is trustworthy. But then, trustworthiness itself had better not turn out to be the idea of what it is reasonable for me to accept, or what I am justified in accepting. Yet, Lehrer's characterization of trustworthiness leads to the suspicion that it either presupposes, or is itself, a veiled concept of justification. For instance, Lehrer says that to be trustworthy in such matters as accepting that I see a zebra, I must have "reason to think" that I can tell that something is a zebra when I see one (138). Trustworthiness implies a high level of success in reaching truth, but it does not entail reliability in every instance. I can be worthy of my trust but be deceived. Lehrer makes it clear that he now believes that a person deceived by the Cartesian demon may still be trustworthy in what she accepts because she proceeds in a virtuous and epistemically faultless manner (140, 211). But notice that, although the deceived person's acceptances are not, in the normal sense of the word, a trustworthy guide to the truth in her circumstances, since they are all false, what is left unmolested by the demon is her justification for her acceptances. She seems to be "trustworthy" only in the sense that her acceptances have been based on justified methods and grounds. So, I strongly suspect that trustworthiness in Lehrer's theory is or involves something like the disposition to form justified acceptances. Consequently, the crucial move/rom trustworthiness to reasonableness may be no real epistemic move at all, but only a question-begging entailment.

7.

SKEPTICISM AND ULTRAJUSTIFICATION

Yes, perhaps we do win the personal justification game against the skeptical critic. In Lehrer's example, a claimant accepts that he sees a zebra. Among other objections offered, the critic proposes that the claimant is generally deceived in a systematic way and sees nothing. But this objection is answered in the personal justification game because the claimant in fact also accepts that it is more reasonable for him to accept that he sees a zebra than that he is systematically deceived. Lehrer suggests that this acceptance is itself based upon the claimant's further acceptances that his evidence is trustworthy, and that the hypothesis of systematic deception is totally improbable on that evidence ([2000a], 133-4). But the uitrajustification game allows the skeptic to eliminate from a person's evaluation system anything false. Presumably, the skeptic takes it to be false that it is more reasonable for the subject to accept that the world is the way he accepts rather than that he is systematically deceived. The skeptic doubts that our evidence philosophically justifies our conclusions. Now, the subject, of course, believes the contrary.

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How does the ultrajustification game go forward, then? We are to envision the critic commanding the claimant to remove some falsehood from his evaluation system, and the removal to be legitimate when, in fact, the acceptance is false. But neither the claimant nor the skeptic knows whether the objection is true or false, i.e., neither knows the answer to the deadlock. And, apparently, neither Lehrer nor we know any more, because, at this point, Lehrer is only able to consider the two possibilities and note their consequences: if it is true that the subject is more reasonable in accepting that he sees a zebra than that he is deceived, then he has undefeated justification, and knows that he sees a zebra; if the skeptic is correct and the claimant's acceptance is not more reasonable than the objection, the subject's justification is defeated, and he fails to have knowledge. Notice that this is no response or reply to the skeptical challenge at all; it is merely a statement of a consequence of Lehrer's theory, that the subject cannot know something unless the skeptic's denial of the subject's reasonableness is false. This is tantamount to saying that Lehrer's so-called "transformation argument" (163) provides no succor against the skeptic. We mustjustifiedly believe that it is more reasonable for us to accept what we see than to accept that we are deceived in order to have an actual response to skepticism. What we might call "Lehrer's fork," the observation that there are two prongs to be considered, one epistemic and one skeptical, does nothing to bolster our belief that our acceptances are more reasonable than the skeptic's challenges. Ifwe do not know, or at leastjustifiedly believe that we are more reasonable, we can't say who wins the ultrajustification game. The fact that the game seems stale-mated at this point, and that Lehrer's fork simply presents the alternatives, is indicative of the fact that we do not know whether we know or not. Nonetheless, in his discussion of skepticism, Lehrer claims the opposite, viz., that we do know that we know. I will turn to that discussion after one final point about the ultrasystem.

8.

RELIABILITY AND THE ULTRASYSTEM

We have already seen that trustworthiness implies high success in gaining truth, but not in every case. A person is supposedly trustworthy in the Cartesian demon world, even though the reliability of his acceptances in that world is nil. The truth of principle (T) does not guarantee a win in the ultrajustification game. The truth of another principle connecting trustworthiness and rei iability also is a necessity. Lehrer says:

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[T]he conversion of personal justification to irrefutable or undefeated justification requires the truth of the following principle: (TR) If I am trustworthy in what I accept, then I am reliable in obtaining truth and avoiding error in what I accept. So personaljustification requires acceptance of(TR) or preference for accepting (TR) over the negation of it. Otherwise the critic will win the justification game. ... For the justification to be undefeated, acceptance of (TR), or preference for accepting (TR) over the negation of it, must be contained in the ultrasystem ([2000a], 194). Hence, in the uitrasystem, (TR) is necessary. But, in the demon world scenario, (TR) is false, and therefore, eliminated. This results in the correct conclusion about knowledge in that world, since the demon's machinations keep us from knowing, but it appears to give the wrong conclusion about our status as justified believers. Our non-skeptical intuition is that, since we know in the actual world, our justification is epistemically sufficient to support knowledge. This justification is unimpeded by the demon, and therefore, even if we do not know in the demon world, since our beliefs are false, our justification in that world is undiminished. However, Lehrer takes uitrajustification, i.e., undefeated justification, to be the justification necessary to support knowledge. But in the demon world, I do not win the uitrajustification game because (TR) is false, and therefore, deleted. Hence, on Lehrer's view, I do not have sufficient epistemic justification in the demon world. This is the wrong answer, intuitively: I should be equally justified in the actual and the demon world. It appears that ultrajustification does not accurately track epistemic justification.

9. SKEPTICISM AND KNOWING THAT WE KNOW We offer no proof that the skeptic is wrong .... We may, nonetheless, know that she is wrong ... and indeed we know that we know (213). Coherence within one's personal evaluation system, plus the truth of the members of that system, such that they ascend to the ultrasystem, is supposed to yield justification, according to Lehrer. I have been arguing that personal coherence plus truth cannot equal epistemic justification, because the skeptical question whether the personal acceptances are truly justified has been side-

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stepped. We have seen that principles that Lehrer requires in any justificatory system, such as principles (T) and (TR) are problematic. (T) seems unjustified by the trustworthiness argument, and (TR) appears to be false in the demon situation, even though its truth is required for epistemic justfication in that case on Lehrer's theory. The defenses against skepticism appear to be depleted. A problem also arises with the claim that, even though no proof can be offered that skepticism is false, we nevertheless know things and know that we know those things. The problem has deep roots in the very structure of the ultrasystem. To see this, consider that everything that a subject accepts with the objective of accepting it just in case it is true, i.e., everything in his personal evaluational system, is something he will believe to be a member of his ultrasystem, or, more precisely, a member of his "T-system," (the subset of the ultrasystem containing only those states, acceptances, preferences and reasonings that are true) (168). Since no subject is omniscient in regard to the possible errors he may have made, he cannot know the membership of his Tsystem. (If he did know that his evidence was in error, then, given that he is motivated to accept things if and only if they are true, he would expunge the error from his evaluation system.) Yet, Lehrer says, A person lifting her hand before her eyes accepts that she has a hand, and she also knows that her justification for accepting this does not depend on any error of hers. She might not know what the members of her ultrasystem are, but she knows that whatever they are, they will leave her justified in accepting that she has a hand. So, she may know and know that she knows ([2000a], 169). But how can this be? Precisely because of the fallibility of our quest for truth, we sometimes accept things that are false or based upon error even when we are doing our epistemic best. In the famous Gettier-style example, I justifiedly believe that Mr. Nogot owns a Ferrari because of the evidence I possess for that acceptance. But I do not know that my conclusion is based upon an error, because I do not know that Nogot is playing a practical joke on me. Hence, although I accept and justifiedly accept that my evidence is not deceptive, I am wrong. So, I do not know the membership of my T-system. Whenever the skeptical critic commands me to eliminate an acceptance in the ultrajustification game, it will come as a surprise to me, since, of course, I hold that acceptance with the objective of accepting something just in case it is true. Now, if the situation is that the necessary principles (T) and (TR) are either unjustified or false, and the person does not know the membership of his ultrasystem, how can it be that the person knows, let alone knows that he knows that the skeptical objections are less reasonable than his own knowledge claims? It seems that he cannot.

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Even to know that I know that I have a hand would require, on Lehrer's theory, that I know that my acceptance that I have a hand is invincible in the ultrasystem. But how can I know this, if! do not have access to the membership of my T-system? The conclusion can only be that Lehrer has not made out his claim that knowledge and meta-knowledge are possible even in the face of skeptical objections. It is easy to see the crucial role played by principles (T) and (TR) in this context. Without a justified acceptance of these principles, it is difficult to imagine any defense against the skeptical objection that it is not more reasonable for a person to accept what he does rather than to accept that he is systematically deceived, or at least in error, in what he accepts. If one's evidence is completely consistent with the skeptical scenario, how can it be thought to positively confirm the person's preferred acceptance? To cite some independent implausibility ofthe skeptical hypothesis appears, again, to be question-begging. Other acceptances of ours may imply such an implausibility, but they, in their turn, are open to the skeptical criticism. Lehrer admits that reliance upon principle (T) is question-begging in any attempt to prove that the skeptic is in error. But he believes that relying upon (T) in explaining why it is reasonable to accept what we do is not vicious but virtuous. He says, To use a premise to prove something to a skeptic who challenges it violates the rules of rhetoric. But to explain why it is reasonable to accept what we do, the circle may be virtuous (143). But vicious circularity occurs in argumentative contexts other than proof. Lehrer's reason for thinking he cannot prove that the skeptic is wrong is that he cannot prove the truth of principle (T) (227). Even if (T)'s best support is straightforwardly inductive and therefore, no question of proof arises, (rather than being based on the dubious loop of trustworthiness) it is still a "rhetorical violation" to assume (T) in any answer to the skeptic who objects that it is not more reasonable for us to believe that we are epistemically connected to the world than to believe that we are systematically in error. That (T) is in our evaluation system and is, perhaps, true is simply not enough to avoid the charge of circularity. To respond effectively to the skeptic, it must be shown that our acceptance of our trustworthiness is not just held but is justified. Nothing Lehrer has offered seems to be up to this challenge. Moreover, it should be remembered that Lehrer's entire picture of what it is to "explain why it is reasonable to accept what we do" (143) is that the subject is able to win the personal and ultra-justification games against the skeptical critic. This may not constitute proving that the skeptic is wrong, but it surely involves being able to

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answer the skeptic's objections in a non-question-begging manner. We have seen that this is a more difficult task than Lehrer has admitted.

10.

SKEPTICISM AND REASONS

In the preceding section, I asked the question how evidence completely consistent with the skeptical hypothesis could be thought to positively confirm our natural belief that we are in contact with the world in the way we accept. Lehrer takes up this question in his discussion of skepticism, and says this: [H)ow can we know that we are not deceived when the reasons we accept for concluding we are not deceived are exactly the same reasons we would accept for concluding we are not deceived if we were deceived? The reply is that though the content of the reasons we accept would be the same, the reasons we accept would not be the same. In the one case, in the actual world, the reasons would be true and in the other case, in the demon world, they would be false. This is a crucial difference ([2000a),212).

But, first of all, my reasons for believing what I do in the demon world are not false, if those reasons are construed as acceptances of the sort, "It appears to me now that there is a zebra in front of me." The demon makes it false that there is a zebra in front of me, but does so while giving me the misleading but true evidence that there appears to be a zebra here. Secondly, and far more importantly, Lehrer's suggestion that we individuate reasons by considering their truth-values is highly counter-intuitive, and leads immediately to unacceptable results. My reasons for believing that Nogot owns a Ferrari are the same whether or not he owns the car or is playing a practical joke. In either case, they have to do with the likelihood that someone would have officiallooking papers, assert that he owns a Ferrari, and be seen driving a Ferrari ifhe did not own the car. My reasons are, as in the demon-world scenario, actually true: I did see official-looking papers, hear Nogot assert that he owns the Ferrari, and see him driving the car. If Lehrer means that it is not the evidence that is false, but, rather, the conclusion they support, then we are still left with unacceptable results. I take it that in the ultrasystem, we are to eliminate any false reason I have for my ultimate acceptance. But then, eliminating my acceptance that Nogot owns a Ferrari as my reason for believing that someone in my office owns a Ferrari is, allegedly, not to eliminate the same reason I have for believing that someone owns a Ferrari if, in fact, Nogot does own the car. This seems, simply, wildly counter-intuitive. Reasons must be individuated on their content alone, and not

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on their truth-value. To do otherwise is to confuse their evidential value with their truth value. Lehrer's view has always been that if a personally justified reason remains undefeated in the ultrajustification game, then the subject may know what he accepts on the basis of that reason, while if it is defeated, then knowledge is not achieved. It is one and the same reason that is being judged for its invincibility in the ultra-game; it is not one reason if true and another if false.

11.

FALLIBILITY AND TRUSTWORTHINESS

I mentioned above that our fallibility regarding our evidence makes it implausible, on Lehrer's theory, that we know that we know, and more particularly, makes it unclear how it is more reasonable for us to accept that we are connected to the world in the ways we assume rather than accepting that we are not connected and are, perhaps, systematically in error. Lehrer takes up these matters in one final argument, and this will bring us full circle back to our original observations about the trustworthiness principle. Here is Lehrer's response: The objection based on fallibility is neutralized by our trustworthiness. It is as reasonable to accept both that we are fallible and that we are trustworthy in a truth-connected way as it is to accept only that we are fallible. It is then as reasonable for us to add that we are trustworthy in this way to the objection and accept both the possibility of error and our trustworthiness in avoiding error in a truth-connected way as to accept the skeptical worry alone ([2000a], 220). This sounds like an answer to skepticism: we are trustworthy in a truthconnected way, therefore the skeptical objection that we are not connected to world as we accept is neutralized. But what Lehrer says next is telling: In those instances in which we are trustworthy in a truth-connected way our justification may be undefeated by local errors and convert to knowledge. In those instances in which we accept that we are trustworthy when we are not, on the other hand, the neutralization fails in the ultrasystem and our justification is defeated (220). This passage, however, says only that ifwe are trustworthy in a truth-connected way, then we can neutralize and defeat any skeptical challenge, and ifwe are not trustworthy and reliable, then our justification will be defeated.

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One cannot establish that it is reasonable for us to accept that we are trustworthy in many cases of our acceptances by pointing out that in cases in which we are trustworthy, we defeat the skeptical objection. The latter claim is a theorem of the theory, while the former is a substantive epistemic assertion. The substantive claim requires justification: we cannot merely accept that we are trustworthy, and wait for that claim to turn out true and, therefore undefeated, in the ultrasystem. I might irresponsibly accept that I am clairvoyant, and, if it turns out that I am, I still do not know what I accept on the basis of my clairvoyance, without a good reason to believe that I am clairvoyant. I have, as Lehrer himself puts it, no reason in such a case to believe this information is correct. We have seen that the most "direct" argument for the justification of my acceptance that I am trustworthy is supposed, by Lehrer, to be the "loop of trustworthiness," but we have found this argument wanting. We have also acknowledged that Lehrer believes that there is good inductive support for principle (T), but very little in the way of a detailed argument for this has been provided. We are, once again, left with the old Pyrrhonian, and neo-Humean worry that Lehrer has begged the question against the skeptic.

12.

CONCLUSION

Lehrer sees that an evaluation system dereft of principles of trustworthiness and reliability will not produce coherence that supports justification or knowledge. He, therefore, requires them as part of one's personal evaluation system and believes they carry through as truths to the ultrasystem. Knowledge requires this. But, for all his talk of loops-loops of trustworthiness, and loops of explanation ([2000a], 227)-we have been hardpressed to see how those loops are not circles in the epistemically vicious sense in which no justification is generated. Skepticism is acknowledged by Lehrer as a serious and coherent threat to knowledge. This paper has been an attempt to show that Lehrer's recent theory lacks the theoretical agility to loop around the skeptic and lead us to knowledge and meta-knowledge.

ENDNOTES 1 Latest expressions of Lehrer's view can be found in Lehrer [1996], Lehrer [2000a] and Lehrer [2000b]. My attention will focus most upon chapters 6-9 of Lehrer [2000a].

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A person's evaluation system is a newer, more robust conception of what Lehrer used to call the acceptance system of a person. The acceptance system contained only acceptances (belief-like states), but the evaluation system now contains not only acceptances, but preferences to accept one thing over another, as well as reasoning structures or strategies. The additions have been made to allow doxastic preferences to count towards judgments of comparative reasonableness, and to meet objections that the acceptance system did not reflect the inferential structure of a person's reasoning and therefore could not reflect whether the person was justified in her beliefs. 2

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REFERENCES Lehrer, K: 1996, Self Trust, A Study of Reason, Knowledge, and Autonomy, Oxford University Press. ---- :2000a, Theory of Knowledge, Second Edition, Westview Press. ----: 2000b, "Discursive Knowledge," Philosophy and Phenomenological Research, Vol. LK, No. 3,637-653.

Chapter 17 COHERENCE, KNOWLEDGE AND SKEPTICISM* Peter Klein Rutgers University

1.

INTRODUCTION

About twenty years ago Keith Lehrer wrote this about how he does philosophy: ... In philosophy, we do not have experiments, only the light of reason to guide us ... Anyone who obscures that light is defeating the enterprise . . . Should I ever reach the point at which I am disinclined to seek criticism and amend my views in light of it, I shall take to writing fiction . . . and give up writing philosophy altogether. Criticism is the touchstone of philosophical inquiry, and those who shunt it aside ... are phonies and beguilers. I Now, we could all say such things. But Lehrer exemplifies this ideal. I have always admired him for that. My comments about his most recent account of knowledge should be taken as part of a long series of discussions we have had over the years. I have always learned a great deal from them. My bet is that his reply to my comments will amply demonstrate that he is not about to take to writing fiction. 281 E.J. Olsson (ed.). The Epistemology of Keith Lehrer, 281-297. © 2003 Kluwer Academic Publishers.

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BRIEF DESCRIPTION OF LEHRER'S VIEW AND A GENERAL QUESTION

Lehrer's account of knowledge has evolved over the years but there have always been two central concepts designed to grapple with two central problems in epistemology. 2 Justification is held to be a matter of coherence and knowledge is taken to be true, undefeated, justified belief. Those two central concepts have provided evolving responses to the Gettier Problem and skepticism. 3 Those two problems are not unrelated. The Gettier Problem pointed to the felicitous, coincidental fulfillment of the justification and truth conditions of knowledge in rather mundane situations. Skepticism-at least of the academic as opposed to the pyrrhonian variety-is motivated by envisioning scenarios in which we have fulfilled our epistemic responsibilities to accept only those beliefs that pass the requirements for justification but nevertheless fall short of knowledge because even if the beliefs are true, it is a lucky accident because, given what justified our beliefs, it could easily be that our beliefs are false. If the demon were sleeping, perhaps there would be hands on some occasion when we are justified in believing that there are hands. But that would be a lucky break for us. I want to consider the adequacy of Lehrer's most recent treatment of the Gettier Problem and skepticism, but it is first necessary and useful to sketch the main outlines of Lehrer's accounts of knowledge and justification. There are places where I might have misunderstood them and laying them out will give him an opportunity to teach me once again. Let me say, first, that I agree with Lehrer that knowledge is true, undefeated justified belief. But since the devil is in the details, we must look at some of the more important features of the account. Here are some of them [TK 129-137]: 1.1

a proposition p is personally justified for S iff P coheres with S's evaluation system, E;

1.2

P coheres with E iff everything that is an objection to p is either answered or neutralized;

1.3

0 is an objection to p for S on E iff it is less reasonable for S to accept that p on the assumption that 0 is true than on the assumption that 0 is false;

1.4

an objection, 0, to p is answered for S on X iff it is more reasonable for S to accept that p than to accept that 0;

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an objection, 0, is neutralized by n iff (0 & n) is not an objection to p and it is as reasonable for S to accept (0 & n) as to accept 0 alone. 4

A key notion here is the evaluation system. An evaluation system for S is made up of the set of states of S's acceptances, preferences and adopted patterns of reasoning - those are states that S has, given only the interest of pursuing truth and avoiding falsehoods. So, for example, if S believes that h, someone owns a Ford, as a result of his interest in pursuing the truth, then "S accepts that h" is a member of the acceptance set. The step to knowledge is relatively easy. Roughly, undefeated justification can be defined as personal justification that is not based on error. More precisely: Let us define S's ultrasystem as the subset of the evaluation system of S obtained by removing all those acceptances whose contents are false, removing any preference for anything false over anything true, and removing all those reasonings that fail to exemplify cogent or valid inferences. 5 Whatever still remains justified in the uitrasystem is knowledge. In other words, if S's ultrasystem has the power to answer or neutralize any objection to S's belief that h, then S knows that h. For example, if S' s belief that h, someone owns a Ford, were based upon a false belief, f, Nogot owns a Ford, then the justification for h would be defeated because fhas been removed from the evaluation system and S no longer has a basis for answering or neutralizing objections to h. Lehrer's treatment of the distinction between the misleading Grabit case, in which S does have knowledge, and Harman's Civil Rights Worker case, in which S lacks knowledge, illustrates how his suggestion is intended to work. 6 Recall that in misleading Grabit case, S sees Tom steal a book and accepts that he did. But Tom's demented father says that it wasn't Tom, it was Tom's twin, Buck. In the newspaper case, S reads of the assassination of a civil rights worker, but the paper later retracts the claim and everyone around S accepts the revised report. In the misleading Grabit Case, no change is required in the uitrasystem because the reasoning did not include any false belief about what the demented father said. The uitrasystem has the power to at least answer if not neutralize the objection that Tom's father said that Buck did it. In the newspaper case, S would have used (at least implicitly) the background belief that the newspaper was reliable and once that is removed from the evaluation system there is no way to answer the objection that the newspaper was unreliable in its reporting(s) about the assassination. 7 The primary points I wish to raise about this account are these: 1.

Lehrer's new solution to the Gettier problem appears not to succeed.

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Lehrer's response to the skeptic appears not to succeed; and there is an alternative available.

Before turning to those points, I have a general question I wish to ask about the account of knowledge. It is prompted by considering a case I will calI the "Medical Diagnosis on-the-Cheap Case." The case goes like this: 8 I come to accept that Mr. D. Pendable will attend the next Pacific AP A meeting roughly a year from now because I accept that he is scheduled to give a paper at the meeting, I accept that he says he is going, and I accept that he has kept his commitments in the past. So, it looks like the proposition Mr. D. Pendable will attend the Pacific APA meeting is at least prima facie justified for me. But is it personally justified according to Lehrer's view and, if so, could it also be knowledge? If it is knowledge, then if Closure holds, do I know that between now and next year Mr. D. Pendable will not have a fatal heart attack? The answers appear to be,jirst, that on Lehrer's account I am personally justified in accepting the proposition that D. Pendable will go to the meeting a year from now because it coheres with my E-system. I could answer (in Lehrer's terms) the obvious objection that some people do not fulfill their commitments even when they intend to by invoking the same strategy that Lehrer invokes in replying to the skeptic to be discussed later, namely, by claiming correctly that it is more reasonable for me to accept that D. Pendable will go to the APA than to accept that he will have a fatal heart attack. Second, on the assumption that there is no relevant false belief in my acceptance set, the ultrasystem would sanction the personally justified belief as knowledge. And if so, unless Closure is false, D. Pendable and I would know that he won't have a fatal heart attack (or that he won't die in a car crash or that he won't be struck by a meteorite or ... ). I will assume that closure holds for Lehrer, since a coherentist seems almost honor-bound to accept it. I think this is just a specific instance of what seems to be a general problem with many forms of coherence theories of justification. It is this: On this view, it appears that whether some proposition, say q, is justified, Le., reasonable to believe in the face of objections, will depend on the epistemic relationships that q has to the other elements of my current evaluation system, E - including that system's resources in answering or neutralizing objections to q. So, whether I am permitted to or should accept a new proposition into E depends solely upon what is currently in E. E-systems can expand incrementally always using the immediately prior E-system. And I can use the existing ESystem to answer objections to a new, candidate proposition to be added to the existing E-System. But what worries me about this is that it would seem to sanction the addition of a proposition to some distant ancestor E-system in a

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step-by-step process as the E-systems evolve that would not have been permissible in one giant step from the ancestor system. But that shouldn't be. I take it that this is the lesson from considering the Sorites situations. It could be reasonable to add p to some system, E, and to add q to the (E + p) system, but not reasonable to add q to E. The objection that it would not have been reasonable for you to accept q on the basis of the original E-system can be neutralized by the proposition that it is now reasonable on the basis of the (E + p) system. The case of Mr. D. Pendable and the more general possible problem with coherence theories were presented just to get the theory before us. I will return to them briefly at the end of the next section. Now, I want to turn to the two main items I wish to discuss: The Gettier Problem and Skepticism.

3.

THE GETTlER PROBLEM

First, to show that the conditions are not necessary: Suppose there is some false proposition,/, that I accept. Further, suppose that I know that I accept / on the basis, no doubt, of introspecting my acceptance set. I am personally justified in accepting that I accept! But since the proposition "I accept thatf' would not be in the ultrasystem (since/is false), I would have no way to answer or neutralize the objection that I don't accept/and, hence, "I acceptf' would not be justified in the ultrasystem. 9 I am quite sure that with a little chisholming that problem can be fixed, although I don't quite see how to do it because, if I understand the account correctly, "I accept thatf' cannot remain in the ultrasystem and it seems that it must in order for me to be able to answer the objection that I don't accept! Indeed, the proposition "I accept f' would seem to ill-cohere with what else would remain in my ultrasystem since it would seem to include a proposition like the following: The best way, and a very good way at that, to determine what I accept is to introspect my acceptance set of beliefs. Second, the more difficult issue, and the one directly related to the traditional Gettier Problem narrowly construed, has to do with sufficiency. Consider a case we can call the Closed-Box Case: Suppose I am looking at a closed box and I (think) I hear Sally tell me there is a drawing of a triangle in the box. On the assumption that I have good reasons for believing Sally, I would seem to be personally justified in believing that there is a drawing of a triangle in the box. I infer from that proposition that there is a drawing of a plane, closed figure in the box the sum of whose interior angles is 180 degrees.

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The following propositions are in my acceptance set and are personally justified for me: 3.

Sally said that there is a drawing of a triangle in the box.

4.

There is a drawing of a triangle in the box.

5.

There is a drawing of a plane, closed figure in the box whose interior angles sum to 180.

Now add to the story that Sally didn't say that there was a drawing of a triangle in the box. I seriously misheard her. She actually said that there wasn't a drawing of a triangle in the box. Presumably, then, I didn't know that there was a drawing of a triangle in the box, even though it was personally justified for me. But, now add one more twist to the case. Sally was wrong. There really was a drawing of a triangle in the box! The following propositions are in my ultrasystem: 2.

There is a drawing of a triangle in the box.

3.

There is a drawing of a plane, closed figure in the box whose interior angles sum to 180.

The problem is that 2 is justified or coheres with the evaluation system because 3 provides a perfectly good, indeed an entailing, reason for 2! Lehrer might perhaps suggest that in the acceptance set and ultrasystem there will be such meta-evaluative propositions as: I actually (formerly) accepted both that there was a drawing of a triangle in the box and that there is a drawing of a plane, closed figure whose interior angles sum to 180 degrees because I actually (formerly) accepted that Sally said there was a triangle in the box. I might note that I no longer accept that Sally did say that and hence, I might conclude that I am no longer justified in accepting the propositions about what is in the box. There are four replies to this. First, I might not have such meta-beliefs about the reasons for my actual acceptances. If it is required that we must have such beliefs in order to possess knowledge, too much of our knowledge would be lost. Think of the person who believes that the Battle of Hastings was in 1066 but has no recollection of the basis on which she believes it. Does she forfeit knowledge?lo A second and related point is that this requires that we have metabeliefs about acceptances and their evidential relationships in order to have knowledge. So, in order to have knowledge that there is drawing of a triangle in the box, we would all have to be epistemologists and even employ the notion

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of "acceptances" (or an equivalent) in our epistemology. That seems a bit much to ask. Third, if in order to know that p I have to correctly identify its evidential basis (if it has one), it seems that calling Lehrer's view a "coherence view" is seriously misleading. For ifthere is such a requirement, then propositions can be ordered by evidential priority and either that ordering stops at some basic proposition or it doesn't. If it does, this is really a disguised form of foundationalism. If it doesn't, then this is really a disguised form of infinitism.ll Andfinally, it simply is not true that I am no longer justified in believing that the box contains a drawing of a triangle - at least according to Lehrer's coherence account ofjustification. For I do have a proposition in my ultrasystem that gives me the ability to answer or neutralize any objection to the proposition that there is a drawing of a triangle in the box, namely: There is a drawing of a plane closed figure whose angles sum to 180 degrees. So it appears to me that the traditional Gettier Problem, narrowly conceived, has re-emerged because the Case of the Closed Box is one in which there is a true, justified acceptance which is not knowledge. The reason is exactly the same one that led to the two original Gettier cases (Jones and his coins; Brown and his trip to Barcelona), namely that there are situations in which our acceptances fall short of knowledge because it is a felicitous coincidence that we have arrived at a true, justified acceptance. 12 The problem strikes me as a general one with Lehrer's account that is not fixed by a bit of chisholming. The reason is that a false proposition or conjunction of false propositions can often provide very good reasons for believing a whole set of internally coherent propositions that happen to be true. Think ofa paranoid who happens to be on some one's hit-list. The basis for his acceptances is false, but he might just by accident have come to accept an internally coherent and true set of beliefs. Note that this problem is related to the first questions we considered, namely those connected with the case of Mr. D. Pendable and the more general possible problem with coherence theories. For in all of these cases the evidential ancestry ofthe propositions in question is not correctly taken into consideration. In the case we just considered, the fact that all of the evidential support for the internally coherent propositions rests upon a significant falsehood is lost. In the case ofMr. D. Pendable and in the general case we have no way of keeping track of the evidential ancestry of our acceptances. As we move further and further from the original basis of our beliefs, although the degree of coherence of our beliefs might increase, they actually become less and less justified. That strikes me as a very general problem with this type of coherence theory. Evidential priority-something that a foundationalist takes seriously-seems to be left out of the picture. 13

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SKEPTICISM

Let us turn to skepticism. Once upon a time, Lehrer defended the plausibility of academic skepticism by suggesting that when we are doing philosophy no hypothesis should be epistemically privileged over another unless some reason, presumably a non-question begging reason, could be provided. Here is what he said then: ... generally arguments about where the burden of proof lies are unproductive. It is more reasonable to suppose that such questions are best left to courts of law where they have suitable application. In philosophy [emphasis added] a different principle of agnoiology [the study of ignorance] is appropriate, to wit, that no hypothesis should be rejected as unjustified without argument against it. Consequently, if the sceptic puts forth a hypothesis inconsistent with the hypothesis of common sense, then there is no burden of proof on either side ... [WNS, 53] The passage is a bit ambiguous, but suppose that it means that when doing philosophy there is no presumption in favor of any two conflicting hypotheses and that in order to accept one of them one has to first have good evidence against the other. If that is what was meant (and I'm not at all sure it was), Lehrer no longer seems to hold this view since he now believes that we can use "It is more reasonable for me to accept that I see a zebra than that I am asleep and dreaming that I see a zebra" in our response to the skeptic/critic who poses the objection, "You are asleep and (merely) dreaming that you see a zebra." In other words, I don't have to first eliminate the hypothesis that I am asleep and merely dreaming that there is a zebra in order to be justified in believing that I see a zebra. I think rejecting the requirement that there is some obligation to eliminate all contrary hypotheses to some proposition, say h, prior to our being justified in believing h is surely correct. For if it were a requirement-even for doing philosophy-the road to skepticism would be way too short to be worth traveling. Consider any two contraries, C 1 and c2 • In order to be justified in believing c l , S would first have to eliminate c2 • And in order to be justified in believing that c2, S would first have to eliminate c l . So, of course, S could never be justified in believing either c 1 or be justified in believing c2. And since every contingent proposition has a contrary, if this requirement were accepted, knowledge of all contingent propositions would be automatically prohibited. 14 In so far as skepticism remains a disputable and interesting philosophical position, the skeptic cannot impose such an outrageous departure from our ordinary epistemic practices.

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So, Lehrer was right in rejecting that stringent requirement. Here is what he now thinks we can say in response to the skeptic: I can tell that I am awake and not asleep and dreaming now. My experience does not feel at all like a dream and I have a distinct memory of what preceded my present experience, leaving my hotel, taking a cab to the zoo, buying a ticket, all of which is trustworthy information that I am now at the zoo looking at a zebra and not asleep and dreaming. (TK, 133) Thus, in response to the skeptic we appeal to two types of beliefs: (i) particular beliefs about our experiences and (ii) a general belief that such information is trustworthy. This strategy will put off the skeptic for a while, but not for long. The skeptic will quicky note that in answer to all of her objections, the general proposition that my information is trustworthy keeps recurring. And she will see that her better objection is this: "What makes you think that you are trustworthy in the way that you evaluate information?" Or more simply: "What makes you think that your belief acquisition methods are trustworthy?" This should be reminiscent of Descartes' strategy on behalf of the skeptic in the "First Meditation." There, he considers and rejects many grounds for doubting the objection that he has trustworthy information about the world. For example, he considers the objection "your senses have misled you in the past" and, in Lehrer's terminology, neutralizes it by adding to it the proposition that he can distinguish those occasions when his senses are trustworthy from those when they aren't. Later Descartes considers the objection that perhaps he is dreaming now and neutralizes it by responding that dream images are like "painted representations" and have been formed as the "counterparts of what is real and true." So, if we limit our acceptances to those "simple" properties shared by dream-images and waking images, we still can arrive at knowledge. Thus, Descartes answers these initial objections by neutralizing them in the way recommended by Lehrer. But then, the Cartesian dialectical skeptic raises this doubt: ... nevertheless in whatever way they suppose that I have arrived at the state of being that I have reached ... since to err and deceive oneself is a defect, it is clear that the greater will be the probability of my being so imperfect as to deceive myself ever, as is the Author to whom they assign my origin the less powerful. 15 In other words, the skeptical objection now is this: "You do not have trustworthy belief acquisition methods." This is the heart of academic skepticism. The academic skeptic requires that there be some way within the E-System to answer or neutralize this

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overarching objection. Famously, Lehrer seeks to provide the answer to the academic skeptic in this manner: He identifies a proposition (T) namely, I am trustworthy (worthy of my own trust) in what I accept with the objective of accepting something just in case it is true. And, he thinks that it is more reasonable to accept T than to deny it or withhold acceptance. In other words, T is in the E-system. The following is a very close paraphrase (including direct quotations) that presents why he thinks T is acceptable. 16 Any argument for (T) would involve a kind of circularity for I would have to appeal to (T) in the argument. So such an argument will not succeed in answering the skeptic, because to use a premise to prove something to a skeptic who challenges it violates the rules of rhetoric. But to explain why it is reasonable to accept what we do, the circle may be virtuous. Ifwe have a principle that explains why it is reasonable to accept what we do, it is a virtue rather than a vice that it should at the same time explain why it is reasonable to accept the principle itself. The other alternative is that the principle should be a kind of unexplained explainer that explains why it is reasonable for us to accept other things we accept and then falls mysteriously silent when asked why it is reasonable to accept the principle itself. The loop by which the principle explains why it is reasonable to accept the principle as well as other things is worthy of epistemic praise rather than rhetorical condemnation (TK, 143). Well, loops could be just as vicious as circles, so that metaphor won't carry the day. The issue here is to get clear about what the reply to the skeptic actually consists in. If asked by the skeptic why I accept T, I reply that by accepting T my acceptance system is more coherent than it would be were I to deny T or withhold acceptance T. If I deny T, I would be saying that I accept some proposition, say p, but that I accept that I wasn't trustworthy in doing so. If I withhold T, I would be saying that I accept p but that I remain neutral about whether I am trustworthy in accepting that p. There is one other way to be coherent, namely, not to accept any proposition at all. With some important caveats that is exactly what the Pyrrhonians did, and it is the view I want to explore. To begin, note that Lehrer says that "any argument for (T) would involve a kind of circularity for I would have to appeal to (T) in the argument. So such an argument will not succeed in answering the skeptic, because to use a premise to prove something to a skeptic who challenges it violates the rules of rhetoric .I agree that if an argument for T employed T as a premise, it would "violate the rules of rhetoric." But as I will argue shortly, I do not think that an argument for Twill, of necessity, employ T. Nevertheless, what is crucial here is that Lehrer

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says that the "loop" explains why it is "reasonable" to accept T, and hence the viciousness associated with an argument for T does not arise. Thus, a central question becomes this: What is the crucial difference between an explanation that shows why it is reasonable to accept a proposition and an argument for the truth of the proposition? Lehrer is correct that there is a crucial difference between explaining p and giving an argument for p. Doing the first is completely consistent with assuming that p. Both I and my critic agree that p is true. In asking for an explanation of p, the critic is asking why p is true. The rhetorical situation is such that p's truth is not at stake. So, explaining that p will not beg the question-since the question is not whether p is true, but why p is true. But that is not parallel to the worries concocted by the skeptic. The skeptic is not willing to grant that T is true. She wants to know whether T is true; not why T is true. In other words, giving an explanation of why T is true will neither answer nor neutralize the skeptic's challenge. It will not answer it, because it presupposes that T is true. It doesn't neutralize it because it does not provide a basis for accepting ~ T along with something else that overrides the impact of ~T alone. In short, the distinction between explaining and giving an argument for will not help here. The skeptic isn't asking for an explanation of T. The skeptic is challenging the truth of T. That being said, it still might seem that the more satisfyingly coherent thing to do is to accept T. And coherence is the essence of justification, according to Lehrer. After all, wouldn't there be something deeply incoherent in thinking that my belief formation methods are unreliable or even just that they might not be reliable. Ernest Sosa has argued for just that point. Here is what he says (this is a close paraphrase): But now suppose that by using way W of forming beliefs ... we arrive at the conviction that W is our way of forming beliefs. Now, so long as we do not go back on that conviction, does that not restrict our coherent combinations of attitudes? Take: (e) Believe that W is my overall way of forming beliefs. And compare (f) Believe that W is reliable, (g) Deny that W is reliable and (h) Withhold that W is reliable. It is not evident that (e) & (f) would be more satisfyingly coherent than either of (e) & (g) or (e) & (h)? 17 My primary question is this: Is it necessarily more satisfyingly coherent to accept T rather than withhold T? My primary answer is that it is not, and by sketching the answers to three secondary questions, I hope to show that the primary answer is at least plausible. Those three questions are: 1.

Assuming that we accept some propositions, must a response to the skeptic involve answering or neutralizing the academic skeptic's objection?

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COHERENCE, KNOWLEDGE AND SKEPTICISM 2.

Ifwe do choose to respond by giving an argument for T, must that argument beg the question?

3.

Must we be forced into providing any response at all to this type of skeptic?

Let us take them up in order. 1.

Assuming that we accept some propositions, must a response to the skeptic involve answering or neutralizing the academic skeptic's objection?

Even if we assume that we accept some propositions that the skeptic challenges, we are not forced either to answer or to neutralize the skeptic's objection. There is another, I think better, strategy available, namely to question the basis on which the skeptic believes or even raises the objection. The skeptic asserts that, or at least seems to be questioning whether, our methods of belief acquisition are unreliable. She dares us to come up with an argument for T that doesn't presuppose T. But why are we limited to either answering the objection or neutralizing it on the basis of something else we believe? Why can't we simply ask the skeptic for her reasons for thinking that T is false? Suppose that we thought that all stated arguments about what is a subject of genuine controversy were either question-begging or based upon arbitrary premises-ones which cry out for a defense before the conclusion is accepted. That was what the Pyrrhonians thought and their strategy in dealing with the dogmatists-whether they were the type who accepted that we had knowledge or the Academic Skeptic type who accepted that we didn't have knowledge-was to ask for the reasons for the accepted proposition in order to show in case after case that either the offered reasons begged the question or begged for further defense. The Pyrrhonians would point out that either the skeptic will or will not have some argument like the following to present:

1.1 1.2

1fT, then some condition, C, holds. C does not hold.

:. Not T Consider the first alternative: If the skeptic has no argument with this form, why should we take the challenge seriously? After all, we have already said that we need not eliminate all contrary hypotheses before we are justified in believing a given hypothesis. And if! don't have to eliminate all of them before

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arriving at the view that the animals are zebras, why would I have to eliminate all of them after I have arrived at the belief that the animals are zebras? So, there must be something special about this challenge that requires that we answer it. It cannot merely be, as some contextualists have suggested, that a hypothesis becomes a relevant alternative to h (one which must be eliminated prior to being justified in believing that h), whenever it is raised-even raised with a serious tone. IS Consider the zebras again. Suppose the skeptic says, "Well how do you know that those things are not cleverly disguised aliens from a recently discovered planet outside our solar system? Or that they are not newly invented super-robots? Or that they are not members of the lost tribe of Israel who have been practicing the zebra-disguise since the 8th century BC, and consequently, have gotten very good at it?" Those objections are so far-fetched so that even if someone advancing those alternatives happens to believe them, there appears to be no reason why one should have to rise to the bait and eliminate those alternatives either before or after one has arrived at the belief that the animals are zebras. And finally, isn't the skeptical hypothesis-that we are not in the actual world but rather in one which just seems identical to it-just as far fetched? What is so special about that far-fetched hypothesis?19 Now to the second alternative: If the skeptic does have such an argument, we can examine it. And we might just find that the Pyrrhonians were right, at least about this argument. 20 Thus, I think we are not forced either to answer or to neutralize the skeptic's claim on the basis of some of our other acceptances. Just because the challenge is raised imposes no burden on us to answer or neutralize it. This is the first step in sketching the alternative response alluded to earlier. 2.

Ifwe do choose to respond by giving an argument for T, must that argument beg the question?

Suppose we prefer to answer the skeptic. After all, Lehrer thinks what we are justified in believing depends, in part, on what we prefer. Consider this argument schema: 1. My methods of belief formation are M-type methods. 2. M-type methods are reliable. My methods of belief formation are reliable. An argument instantiating that schema need not beg the question. Of course any person giving such a defense of their belief forming mechanism will, on grounds of consistency in practice, use methods M in coming to believe that her methods of belief formation are reliable. But what's the alternative? To use

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some methods other than M which she thinks are not reliable? That would make her practice inconsistent with her beliefs. The fallacy of begging the question in reasoning consists in using a conclusion of an argument as a basic premise-whether overt or suppressed. Question-begging arguments can provide no additional reason for accepting the conclusion beyond those already available for the basic premises. But it is not a fallacy of reasoning to employ what one takes to be the reliable belief formation rules in arguing for the claim that those very belieffonnation rules are reliable. Indeed, to do otherwise would be to fail to practice what one preaches. Now, the academic skeptic might deny one or both of the premises of the argument. And if the pyrrhonian skeptic is correct, any such argument will either beg the question or rely upon premises that require further defense. Nevertheless, the point here is that the argument for the reliability of methods M need not beg the question. 3.

Must we be forced into providing any response at all to this type of skeptic?

I have already partially addressed that question by arguing that even if we accept some proposition, say p, we need not answer or neutralize the skeptic's objection to p. We can challenge the skeptic's basis for accepting the objection. But, here, I mean to be asking whether we need ever be placed in the position of defending acceptances at all. Of course, we have that burden only if we accept some propositions that could be challenged by the skeptic. My question is this: Why is it assumed that we must accept anything-at least anything that requires inferential support? It is absolutely crucial to note that for Lehrer to accept p is not the same as to believe p. Knowledge entails acceptance not belief. To accept something is to hold it true precisely because doing so promotes our supposed goal of accepting a proposition iff it is true. According to Lehrer we can even know something to be true which we believe is false (again paraphrase and quotation): A politician may convince you of the truth of what he says when you know he is untrustworthy . . . He is warm, human, and comforting, whereas the data are cold, mathematical, and distressing. How can you resist? You do believe him but you know that the economy is slipping. This conflict between belief and knowledge is explained by the fact that we are "divided into two systems." One system is truth-seeking. The other is the yield of habit, instinct, and need ... We do not accept what the pol itician tells us as the bona fide truth even if we cannot help but believe him. (TK, 124-5)

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But what if we thought that our epistemic equipment was not trustworthy enough to arrive at unobjectionable (in Lehrer's sense of that term) truths in matters as complex as evaluating the weight of reasons on each side of a complex issue? What if we thought that we are only trustworthy enough to identifY what seems true? By "seeming true" I do not mean some sort of hesitating endorsement of the proposition's being true. Rather, I mean that the proposition has the look of truth about it. It seems to satisfY what appears to make a proposition true. Further, what if it seems to us that our goal is not and should not be unobjectionable propositions but rather provisionally justified belief in what seems true? That is a goal that seems reachable and does not bring with it the dangerous flirtation with dogmatism that easily accompanies the preference for being in a situation in which we are able to answer or neutralize all objections on the basis of what we currently accept. Recall part of what I cited that Lehrer wrote twenty years ago: "Should J ever reach the point at which I am disinclined to seek criticism and amend my views in light of it, I shall take to writing fiction . . . and give up writing philosophy altogether." Now I suppose that one could seek criticism in the way that an arrogant gunslinger would seek out opponents believing that victory will be his. Such macho philosophic gun fighters have a virtue of their own. But this isn't Lehrer's motivation. He seeks criticism because he expects that it will improve the epistemic worth of his beliefs. That sounds like a person who does not accept that he is ever in a position to answer or neutralize all objections to what he believes. Such a person would never accept the meta-view that he had personally justified acceptances.

5.

ALTERNATIVETOANSWERINGORNEUTRALIZING THE SKEPTIC'S CHALLENGE

Let me briefly summarize where the answers to the three subsidiary questions posed above have left us. We need not "answer"or "neutralize" (in Lehrer's sense of those expressions) the academic skeptic's challenge to our acceptances. We can show that the arguments employed by such a skeptic do not succeed. Further, we can coherently not accept T. But abstaining from accepting T does not necessarily lead to embracing academic skepticism. Such skeptics accept that T is false. The third alternative-the pyrrhonian alternative -is to withhold accepting T. That would bring with it withholding any proposition whose defense against objections depended upon accepting T. It strikes me that such a view is satisfYingly coherent and, indeed, better fits Lehrer's own preference system than the model of justification he has suggested. 21

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NOTES

* I want to thank Anne Ashbaugh and especially Keith Lehrer for their help with this paper. Keith and I have been talking and emailing about some ofthese issues for many years. In particular, an ancestor of this paper was given at the Pacific AP A meeting (March, 200 I). He replied to it there and also kindly sent me some further comments later. Keith has taught me a lot over the years and I expect that his replies to this version of the paper will continue to make me think more about the issues. That's the fun of it all. I. Keith Lehrer: Profiles (Dordrecht: D. Reidel Publishing Company, 1981), ed. Radu Bogdan, p. II.

2.

In this paper I will be relying primarily on these works by Lehrer: Theory

0/ Knowledge (Boulder:Westview Press, 2000), second edition [TK]

"Why Not Scepticism?" originally published in The Philosophical Forum, 2.3 (1971), 283-298. It has been anthologized in many places. Citations to this article are to The Theory 0/ Knowledge (Belmont, CA: Wadsworth Publishing Company, 1993), edited by Pojman [WNS]. Self-Trust: A Study o/Reason, Knowledge and Autonomy (Oxford and New York: Oxford University Press, 1997) [ST] 3. By "skepticism" I will be referring to Academic Skepticism unless otherwise noted. Using Lehrer's terminology, the Academic Skeptics thought that it is more reasonable to accept that we don't (or can't) have knowledge in those areas in which it is generally thought that we do have knowledge than to deny or withhold such a judgement about the scope of our knowledge. This is to be contrasted with the Pyrrhonian Skeptic who would withhold such an acceptance (and its denial). 4. One might worry here that it could never be more reasonable for S to accept a conjunction than it is to accept one of the conjuncts (unless it entails the other) because the probability of the conjunction will be less that the probability ofthe conjunct. But I think the answer is this: Since the goal is to gain truth and avoid falsehood, by accepting the conjunction one has a greater chance of accepting more truths than one would by merely accepting the one conjunct. j I am using "valid" in the standard way to indicate an argument whose pattern is such that any argument with that pattern not possible for the premises to be true and the conclusion false. I am using "cogent" in the way defined by Richard Feldman in Reason and Argument (Upper Saddle River, New Jersey: Prentice Hall, 1999 second edition) to refer to good patterns of inductive reasoning. 6. The best source for a full and illuminating discussion ofthe various counterexamples connected with the early Gettier Problem literature is Robert Shope's, The Analysis o/Knowledge (Princeton, New Jersey: Princeton University Press, 1983). 7 It was unreliable at least in this case because too many of its reports were false. 8. This example, or one very similar to it, was suggested to me as a possible counterexample to some forms of closure by John Hawthorne. I don't think it works against closure because I think a proper account of justification would have it that you are not justified in believing that D. Pendable will attend the meeting. But this is not the place to present that account. 9. This example, or one very much like it, was developed by Robert Shope, op cit, pp. 52, 71, 102. It was also used by Alvin Plantinga in Warrant: The Current Debate (New York and Oxford: Oxford University Press, 1993, pp. 220-1.) I argued that this counterexample would not work against my version of the defeasibility theory in "Warrant, Proper Function, Reliabilism, and Defeasibility" in Warrant in Contemporary Epistemology (London: Rowman & Littlefield Publishers, 1996), pp. 121-2.

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10 Examples like this one were given by Colin Radford, "Knowledge - By Example," Analysis, 27,1966,1-11. 11. Of course, I would be very pleased if some epistemologist other than I thought infinitism is the correct account of the structure of justification! (See fn. 13.) 12 See my paper "A Proposed Definition of Propositional Knowledge," Journal of Philosophy 67.16,1971,471-482. 13. I think neither a coherentist nor foundationalist approach to justification is correct. The third alternative solution to the regress of reasons problem-namely infinitism-strikes me as the best solution and I have argued as much in several papers. See for example, "Human Knowledge and the Infinite Regress of Reasons," Philosophical Perspectives, 13, J. Tomberlin (ed.), 1999,297325; "Why Not Infinitism?" in Epistemology: Proceedings of the Twentieth World Congress in Philosophy, Richard Cobb-Stevens (ed.), 2000, vol 5, 199-208; and "How a Pyrrhonian Skeptic Might Respond to Academic Skepticism," The Skeptics: Contemporary Essays, (ed. Steven Luper Ashgate Press, forthcoming.) 14. Take any contingent proposition, h. The proposition (~h & x) is a contrary, where x is any proposition at all, including (h v ~h). IS. Descartes, "First Meditation" in The Philosophical Works of Descartes (Dover Publications, 193 I) trans. Haldane and Ross, p. 147. 16. The cited text is TK. But a similar argument occurs in ST, chapter I. 17. Ernest Sosa, "Philosophical Skepticism and Epistemic Circularity," Proceedings of the Aristotelian SOCiety 68 (1994), p.107. 18. This is essentially the view put forth by Stewart Cohen in "Knowledge, Context and Social Standards," Synthese, 73 (1987), 3-26 and his "How to be aFallibilist" Philosophical Perspectives, 2 (1988), 91-123, David Lewis in "Elusive Knowledge," Australasian Journal ofPhilosophy, 74 (1996),549-67 and Keith DeRose in "Solving the Skeptical Problem," Philosophical Review, 104 (1995), I-52 and his "Contextualism and Knowledge Attributions," Philosophy and Phenomenological Research, 52 (1992), 913-929. 19 Let me add that Descartes does not simply raise the hypothesis-he gives a reason for thinking that it is at least plausible; namely, that the degree of perfection of his epistemic equipment cannot be higher than the degree of whatever is its cause and, at that point in the Meditations, he has no reason to think that its cause is sufficiently perfect. Thus, in order to see whether we should take this challenge seriously, we would have to examine the presuppositions ofthis skeptical challenge. This is obviously not the place for that. 20. See my paper "Skepticism and Closure: Why the Evil Genius Argument Fails," Philosophical Topics, 23.1, Spring 1995,213-236, and "How a Pyrrhonian Skeptic Might Respond to Academic Skepticism," op. cit. 21. This does have the consequence that neither foundationalism nor coherentism is the correct account of reasoning. As mentioned in fn. 13, I have argued for infinitism in several papers.

Chapter 18 THE ULTRASYSTEM AND THE CONDITIONAL FALLACY David A. Truncellito Arkansas State University

1.

INTRODUCTION

Keith Lehrer's account of justification and knowledge is unique and brilliant. Lehrer's notion ofjustification in terms of coherence can be construed as a matter of beating or neutralizing competitors 1, and his account of knowledge can be construed as a matter ofundefeatedjustification. 2 And competition and defeat can, in turn, be understood via the rubric of the justification game. This is a picture that has persisted throughout Lehrer's epistemological writings-from his earliest efforts to respond to the Gettier problem to his current works-in-progress-although it has evolved over the years. However, although his theory exhibits these unique features, Robert Shope has grouped Lehrer together with a wide range of other contemporary philosophers by accusing him of committing the conditional fallacy. While Shope seems to have argued convincingly that many philosophers are indeed guilty of this fallacy, I shall argue in what follows that Lehrer escapes this charge.

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LEHRER'S TWO-LEVEL ACCOUNT OF JUSTIFICATION

Let us begin by briefly reviewing Lehrer's account of justification and knowledge. For Lehrer, justification comes in two levels: personal justification 299 E.J. Olsson (ed.). The Epistemology of Keith Lehrer, 299-308. © 2003 Kluwer Academic Publishers.

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and undefeated justification; knowledge reduces to undefeated justification. Let us first consider personal justification, which Lehrer has defined as follows: S is personally justified in accepting that p at t if and only if everything that is an objection to p for S on the basis of the acceptance system of S at t is answered or neutralized on the basis of the acceptance system of S at t. 3 That is, personal justification is a matter of answering or neutralizing all objections to one's acceptance that p; in other words, p must cohere with the rest of one's acceptance system. Note that it is S's acceptance system that is the relevant set of propositions with which p must cohere. Also, note that to accept that p is not (merely) to believe that p4, but rather to accept that p with the aim of attaining truth and avoiding error with respect to p.5 S' s acceptance system, then, comprises everything S accepts: The acceptance system of S at t is by definition the set of states of acceptance of S described by statements of the form-S accepts that p-attributing to S just those things S accepts at t with the objective of obtaining truth and avoiding error with respect to the content accepted, that is, with respect to the content that p.6 Personal justification, then, arises when one has the resources within one's acceptance system to reply to any challenge a skeptic might raise. This dialectical formulation of personal justification suggests the justification game. 7 In short, the game is played between S (the claimant), who claims to have knowledge, and a critic (or skeptic), who challenges S' s claims to knowledge by raising objections. S wins a round by adequately answering or neutralizing the critic's objection; S wins the game, and achieves personal justification, by winning every round. Notice, though, that victory in the justification game does not entail that S knows that p. This is for the obvious reason that while S' s acceptances were formed with the goal of attaining truth and avoiding error, he might have failed to meet that goal in some cases; indeed, given that S, like the rest of us, is fallible, it is likely that he did fail to meet this goal in some cases. But since victory in the justification game, and thus personal justification, are based on S' s acceptance system, S's belief that p, although personally justified, might be based on falsehoods. And, while personal justification is a noteworthy achievement, belief based on falsehoods cannot constitute knowledge. This is the motivation behind the' isolation objection' against coherentist-and, indeed, any purely internalistic-accounts of justification. 8

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Lehrer's remedy to this possible problem is unique and elegant. It begins with the simple observation that "complete justification is personal justification that is not based on error.,,9 However, the unique flavor of Lehrer's account of personal justification suggests a unique way of incorporating this relatively straightforward observation. To avoid reliance upon error, let us imagine a new system, which is obtained by retaining all truths and eliminating all falsehoods from S's acceptance system. Call this new system S's ultrasystem. IO We can now playa modified version of the justification game, the ultra justification game. I I The game is played as before, except that the players are now the claimant and the uItracritic. Since the ultra justification game is based on S's uItrasystem rather than S's acceptance system, the uItracritic can make a new kind of move: she may prohibit S from appealing to any of her false acceptances in her efforts to reply to objections. 12 We now see the second level of justification, viz. undefeated justification: S wins a round of the ultra justification game by adequately answering or neutralizing the ultracritic's objection; S wins the game, and achieves undefeated justification and knowledge, by winning every round. 13

3.

THE CONDITIONAL FALLACY

Lehrer's notion of the ultrasystem clearly serves to avoid the worry that accompanied personal justification, namely the possibility of acceptance being based on error. However, it exposes him to a new form of objection-one which might perhaps seem to be less central to the matter of knowledge, but an important objection nonetheless. Namely, it runs the risk of jeopardizing one's knowledge of one's own mental states, which surely no account of knowledge should do. Robert Shope has suggested a common sort of mistake made by a number of contemporary philosophers, which he calls the conditional fallacy and characterizes as follows: A mistake one makes in analyzing or defining a statement p by presenting its truth as dependent, in at least some specified situations, upon the truth (falsity) of a subjunctive conditional 0 of the form: 'If state of affairs a were to occur, then state of affairs b would occur', when one has overlooked the fact that, in some specified situations, statement p is actually true, but, if a were to occur, then it would be at least a partial cause of something that would make b fail to occur (make b occur).14

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Shope then claims that Lehrer is among those many who are guilty of committing this fallacy. IS Others, including Peter Klein l6 , Alvin Plantinga and John Pollock, have offered similar objections to Lehrer's theory. Let me attempt to unify these objections by describing the purportedly offensive sort of case. Let us suppose that S accepts some p, such that p is false. Then, of course, it follows that S does not know that p. But let us suppose further that S accepts that S accepts that p. This latter acceptance (call it S's acceptance that q), intuitively, constitutes knowledge. 17 However, because ofthe way in which Lehrer has characterized undefeated justification, his account has the consequence that S does not know that q, which is a serious mark against the view. Recall that undefeated justification-and knowledge, which is equivalent -requires the ability to win the ultra justification game. We could, then, characterize knowledge in terms of a subjunctive conditional analysis, so as to see just how it is meant to be vulnerable to the conditional fallacy: S knows that p iff if all falsehoods were to be eliminated from S's acceptance system, then S would be able to answer or neutralize any objections to p. But in the case we are considering, we see a problem for Lehrer's account. For, p is among the falsehoods that are removed from S's acceptance system in constructing S's ultrasystem! It follows, then, that S does not know that q (i.e. does not know that he accepts that p).

4.

VINDICATION OF LEHRER'S ACCOUNT

My reply is simple and straightforward: the objection appears to rest on a misunderstanding of Lehrer's account. I shall endeavor, then, to expose this misunderstanding and thus dissolve the objection. I shall do this by sketching a few rounds of the ultra justification game as they would be played in the case under discussion. To show that Lehrer's account has the consequence that S does indeed know that q, I shall show, in turn, that his account has the consequences that S accepts that q, that q is true, and that S is completely justified in accepting that q.18

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S accepts that q

The question we are facing is whether S's acceptance that q is to count as knowledge on Lehrer's theory. As such, it is relatively uncontroversial that S does indeed accept that q; the question regards the status of that acceptance. So, while'S accepts that p' is not part of the description ofS's ultrasystem, 'S accepts that S accepts that p' is part of that description. We need to be careful on this point, though. Note that Lehrer's characterization of the ultrasystem is such that S's acceptances themselves, and not the contents of those acceptances, are described. So, while'S accepts that p' does not accurately describe any part of the ultrasystem, 'S accepts that S accepts that p' does; that is, the acceptance that S accepts that p is among S's acceptances which have not been eliminated in forming the ultrasystem.

4.2. Q is true In order to evaluate the truth of S's acceptances about the world, we need to note whether they hold true of the actual world. In particular, in order to evaluate the truth of S's acceptances about S's acceptance system, we need to note whether they hold true ofS's actual acceptance system. But q is indeed true (i.e. S does accept that p), for p is a member of S's acceptance system, even though it is not a member of S's ultrasystem. We need to recall that the ultrasystem is a new system, and that falsehoods have been removed from the ultrasystem, but have not actually been removed from the acceptance system. Indeed, Lehrer explicitly makes note of this point in his latest book (although not, to my knowledge, in any of his earlier work): "The ultrasystem, nevertheless, is required to acknowledge the existence of the eliminated states of acceptance ... in the original evaluation system, for it is true that they are states of the person.,,19 In other words, the ultrasystem is nothing more than a theoretical construct, designed with the purpose of helping us to evaluate the justificatory status of S's acceptances. But even while we are conducting this evaluation, S's acceptance system remains unchanged: it continues to include any falsehoods which might have been in it previously.

4.3. S's acceptance that q is completely justified Let us suppose that S's acceptance that p is personally justified. This is, I take it uncontroversial, since personal justification depends upon the acceptance system but not the ultrasystem. However, it will be informative to

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ask why S's acceptance is personally justified. Such an acceptance normally derives its justification on the basis on introspection. 20 To make this explicit, then, let us suppose that S's justification for believing that g is supported by his following acceptances: gl: I introspect an acceptance that p. g2: Introspection is a trustworthy source of acceptances about my mind.

The exact details might be different in the case of a particular agent. The crucial point to note, though, is that however the correct account might proceed, S's acceptance that q is not justified by p. Now, let us imagine a round of the ultra justification game. The ultra system will contain q, ql' and q2' but not p, since all falsehoods have been removed in constructing it. Claimant: g (i.e. I accept that p.). Critic: p is false. Not-g (i.e. You do not accept that p). Claimant: It is more reasonable for me to accept g than to accept not-g, on the grounds that gl and g2'

Note that the claimant's response is exactly as it would be in the ordinary justification game, since the critic cannot make the claimant remove ql or q2 from the ultrasystem. But then, it appears that the critic's move does not constitute an unsuperable objection; indeed, the critic's objection is entirely irrelevant to S's acceptance that q. For, S's acceptance that q is based upon ql and q2' and these remain in the ultrasystem. S's acceptance is not based upon p, so the critic's request that S remove p (and, perhaps, replace it with not-p) doesn't generate an objection which can't be answered or neutralized. Consider another round of the ultra justification game: Claimant: g (i. e. I accept that p). Critic: Not-g (i.e. you do not accept that p). The critic's move is illegitimate, since not-g is false (see section IV.2 above), and thus not available to the critic as an objection. So, the only possible objections one might imagine that the critic would raise are not-p, which does not constitute an objection to S's acceptance that g, and not-g, which is false and thus not a legitimate objection. S does, after all, have undefeated justification and knowledge that p.

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I should pause at this point to consider an alternate construal of this objection against Lehrer's theory, which was suggested to me by an ancestor of Klein's paper.21 Note that S's ultrasystem contains the acceptance that S accepts that p, but not the acceptance that p. It appears, then, that S's ultrasystem contains a practical contradiction along the lines of Moore's paradox. However, there is no reason for this to worry us. Since the ultrasystem is a mere theoretical construct, there is no need for it to be free of inconsistencies. If S's acceptance system contained such an inconsistency, that might be troublesome; but this would be a problem for S, not for Lehrer. 22

5. CONCLUSION There may be other problems with Lehrer's account of justification and knowledge, as several ofthe other contributors to this volume suggest. I do not claim to have shown that it is the correct theory, but merely to have defended it against Shope's objection. Perhaps Lehrer's description of the ultrasystem was not sufficiently perspicuous-he might, for instance, have described the members of the acceptance system in terms of their content (e.g. as 'p' rather than as'S accepts that p'), and he might have been more clear that the ultrasystem is distinct from, albeit related to, the acceptance system-and thus led some readers to overlook the fact that it is a new system, and a theoretical system at that, rather than an actual modification to the acceptance system. I hope that I have helped to clarify the matter. 23

ENDNOTES 'Or, in the terminology of Lehrer (2000), answering or neutralizing objections. Lehrer (2000), pp.169ff. 3 Lehrer (2000), p.137. See also Lehrer (1997), p.30; Lehrer (1990), p.126; Lehrer (1974), p.198. In Lehrer (1974), this notion was referred to as complete justification, but it is clearly the ancestor of personal justification. Indeed, Lehrer concedes that the term 'complete justification' should perhaps be reserved for the kind of justification that is sufficient for knowledge, and that this notion might be better called 'subjective justification'. (Lehrer (1974), p.214) 4 Lehrer vacillates as to whether acceptance is a kind of belief (Lehrer (1990), p.ll) or is a kind of mental state distinct from belief (Lehrer (2000), p.14). We might want to say that acceptances are those beliefs which have been positively evaluated with regard to epistemic purposes, but we might also want to allow that S accepts that p without believing that p. This is an interesting matter, and raises issues of doxastic voluntarism (among others). However, for Lehrer's and our purposes, we need only note that it is acceptances and not beliefs that are relevant to justification. s Lehrer (2000), p.13, p.130. See also Lehrer (1997), p.3; Lehrer (1990), p.11. 2

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6 Lehrer (2000), p.130; see also Lehrer (1990), p.117. In Lehrer (1974), this was referred to as the corrected doxastic system (p.190). 7 For a detailed description, and several rounds, of the justification game, see Lehrer (2000), pp.132ff; Lehrer (1990), pp.119ff. I'll rehearse a few rounds of the game in section IV below. S Lehrer is explicit that, although his account is often taken to be an internalistic theory of justification, it is not; it is what he prefers to call a 'match theory'. "There must be a match between what one accepts as a trustworthy guide to truth and what really is a trustworthy guide to truth ... To obtain knowledge one needs the right mix of internal and external factors." (Lehrer (2000), p.I72) However, personal justification is a purely internalistic component of Lehrer's account, in that it is indexed to a subset of S's internal states (viz. S's acceptance system), and that is why it is vulnerable to the worry raised above. 9 Lehrer (2000), p.l53. See also Lehrer (1974), p.215. 10 Lehrer (2000), pp.l53-4. In Lehrer (1974), this was referred to as the verific alternative to the corrected doxastic system. (p.224) 11 Lehrer (2000), pp.154ff; Lehrer (1990), pp.14lff. 12 She may also disallow unsound reasonings (Lehrer 2000), p.160), although that will not concern us here. 13 Lehrer actually added a third, intermediary stage, in Lehrer (1990), viz. verific justification, with its attendant notions of the verific system and the verific justification game. Also, in that work, the ultrasystem was a set of systems rather than a single system. Given that this was not the case in Lehrer (1974), and no longer is the case in Lehrer (2000), I shall ignore it for the purposes of my discussion. In any event, the spirit of the proposal is consistent throughout the development of Lehrer's theory, and that should not be obscured by this wrinkle. 14 Shope (1978), pp.399-400. This is actually Version 2 of the fallacy, which is the version Shope accuses Lehrer of committing. 15 See Shope (1983), pp.48ff, pp.53ff, and especially pp. 73-74. 16 Most recently in his "Coherence, Knowledge and Skepticism", in this volume. 17 The exact details of the way in which S comes to be justified in his acceptance that he accepts that p can be ignored here. Presumably, though, the explanation will have to do with the fact that S introspected such an acceptance and that introspection is a trustworthy source of knowledge of one's own mental states. If one were to deny that S knows that S accepts that p, then of course the objection is rendered irrelevant. I shall discuss the details ofthis case somewhat more thoroughly in the following section. 18 Strictly speaking, since knowledge reduces to undefeated justified acceptance, I do not need to show that q is true. However, I shall do so nonetheless for the sake of clarity and perspicacity. Since the objection of the previous section could be interpreted so that the undesirable consequence of Lehrer's theory is that q is false or that q is not completely justified, I shall respond to both possibilities. 19 Lehrer (2000), p.160; see also Lehrer (2000), p.168. Note that the evaluation system is the system composed of all of S's acceptances, as well as his preferences and reasonings. What is relevant for our purposes, though, is that the acceptance system is a subset of the evaluation system. 20 Klein, in the very paragraph in which he raises his objection in Klein (forthcoming), agrees that this must be the case, so this is a point of agreement between the objector and myself. 21 Presented, under the same title, at the occasion of the 2001 Pacific APA session honoring Lehrer. 22 And, given that Lehrer does not insist that coherence requires consistency, it might not even be that significant a problem for S. 23 Thanks are due to Keith Lehrer for discussion on this topic, and for providing two necessary conditions for this paper: namely, developing the coherence theory of knowledge and helping me to develop my philosophical abilities in general, and the particular thoughts which led to this

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paper, via his guidance as my advisor and mentor. I consider myself extremely fortunate to have been Keith's student, and am extremely happy to have him as a friend. I might note that as I was working on this paper, Keith came to the Mid-South to give a talk at my University, and we spent several days talking about philosophy, walking along the Mississippi River, listening to blues, and generally enjoying each other's company. The pleasant memories of his visit are stilI foremost in my mind as I type these words.

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REFERENCES Klein, Peter, forthcoming. "Coherence, Knowledge and Skepticism." (to appear in this volume) Lehrer, Keith, 1974. Knowledge. Oxford: Clarendon Press. Lehrer, Keith, 1990. Theory of Knowledge. Boulder, CO: Westview Press. Lehrer, Keith, 1997. Self-Trust: A Study of Reason, Knowledge, and Autonomy. Oxford: Clarendon Press. Lehrer, Keith, 2000. Theory of Knowledge (2nd ed.). Boulder, CO: Westview Press. Plantinga, Alvin, 1993. Warrant: The Current Debate. Oxford: Oxford University Press. Shope, Robert, 1978. 'The Conditional Fallacy in Contemporary Philosophy." Journal of Philosophy 75: 397-413. Shope, Robert, 1983. The Analysis of Knowing: A Decade of Research. Princeton: Princeton University Press.

Chapter 19 COHERENCE, CIRCULARITY AND CONSISTENCY: LEHRER REPLIES Keith Lehrer University ofArizona

The essays in this volume on my epistemology are a testimony to the way in which first rate philosophers have involved themselves with my published work in the theory of knowledge stretching over four decades. It is extremely gratifying to me, for the contributors to this volume are among the most talented philosophers of the present day. The contributors to this volume have concentrated on both the general coherence theory I have presented and the analytical details of it. Though they often disagree with the theory and raise objections to it, sometimes in a quite critical manner. I consider their careful examination of the theory as an important contribution to the study of what I have done. Where they disagree most avidly is where I suspect from my own study of the history of philosophy, especially the criticism of Reid against Hume, I have probably made the most important contribution to epistemology even if they are successful in refuting what I have written. Moreover, if they are definitive in their refutation, I shall claim part of the credit in formulating a theory with sufficient clarity and precision so that it admits of definitive refutation. Having expressed my admiration, my genuine admiration, for the philosophical acumen of my critics, I do wish to reply to what they have said. I hope that I shall reply fairly and do justice to their insights. I am afraid that in the fray of debate, it is difficult to decide whether one has been fair or not, but I shall do my best. Part of the problem of replying is that I have changed my views over the last four decades, which is, I hope, a fact that will be looked upon with favor. It would, after all, be a bit disheartening if! simply repeated what I had previously said from year to year for forty years. On the other hand, in considering criticism 309 E.!. Olsson (ed.), The Episterrwlogy of Keith Lehrer, 309-356. © 2003 Kluwer Academic Publishers.

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of views which I no longer hold, particularly views concerning the details of analysis, I am not inclined to engage in dispute about whether some criticism of my now discarded past is well taken. Moreover, in some cases I must admit that I do not consider myself to be the best judge of what Keith Lehrer meant by what he wrote some ten years or more ago, at least I consider myself to be no better judge than some of my interpreters in this volume. So, in some cases, I shall say nothing in reply, though the criticism is important and may even be decisive, simply because I no longer hold the view discussed. In other cases, where the criticism seems based on an interpretation which I had explicitly repudiated, I shall note the fact without pretending to special authority about what Keith Lehrer meant but only noting what he said. Sometimes, moreover, I shall say nothing in reply simply because I have nothing of value to say. My critic should not consider silence on my part as disregard but rather as indication that I prefer to say nothing when I have nothing to say however much inclined I am to think I am right. Silence should not be taken as concession but as a quiet expression of respect. I have done my best to articulate a coherence theory of knowledge elsewhere. As part of replying to my critics, I would like to make another attempt to make it clearer what I now advocate, though I shall not restate the technical details I have presented elsewhere. Here are the main features of the theory as I now see it.

1.

THE COHERENCE THEORY

These are the views I hold which constitute my coherence theory of knowledge. S knows that p if and only if S accepts that p, p, S is personally justified in accepting that p, and Ss personal justification for accepting that p is undefeated or irrefutable by errors of S. This account reduces to the theory that S knows that p if and only if Ss personal justification for accepting that p is undefeated or irrefutable by errors of S. Personal justification is a relation of coherence between a target acceptance and an evaluation system of a subject that enables the subject to meet objections to the target acceptance. An evaluation system consists of states of acceptance, preferences over acceptances and reasonings concerning acceptances. Undefeated or irrefutable justification of a person is a relation of coherence between a target acceptance and an ultrasystem constituting a system in which the errors of acceptance, preference and reasoning in the evaluation system of a person are disallowed for the purpose of answering objections to the target acceptance. The ultrasystem consists of truth states, tacceptances, t-preferences and t-reasonings, of the original evaluation system together with acknowledgment of the other states of the original evaluation system. The ultrasystem is intended to provide a test for undefeated justification disallowing the use of errors in the original evaluation system.

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The test for undefeated justification proceeds as follows. We allow conditional reasoning, something analogous to conditional proof, from the system of acceptances that are acceptances of true propositions. All acceptances of propositions that are true may be called t-acceptances. Though the acceptance system of the person remains what it was in the original evaluation system, only the content of those acceptances that are t-acceptances may be used to meet objections to what is accepted for the purposes of testing for coherence and, thus, justification on the basis of the t-acceptance system. This restriction to the use of the content oft-acceptances for meeting objections has the effect of blocking the use of the content of acceptances of things that are false in reasoning while at the same time acknowledging their existence. The t-acceptance system is used instead of the acceptance system in the evaluation system for the purpose of testing for coherence and justification without eliminating or replacing the acceptance system. We must, of course, introduce a set of conditional preferences and reasonings to be used to meet objections and test for undefeated justification as well as introducing the t-acceptances. The set of conditional reasonings or t-reasonings is restricted to the subset of original reasonings that contain true premises. The set of conditional preferences or t-preferences is restricted to the set of preferences for acceptingp to accepting q in the interests of truth in which it is not the case that p is false and q is true. (This holds for weak t-preference as well.) The t-reasonings and t-preferences are subsets of the original preferences and reasonings in the evaluation system. The original preferences and reasonings are not eliminated or replaced in the evaluation system, but the use of the content of preferences and reasonings to meet objections and test for coherence and undefeated justification is restricted to the content of t-preferences and t-reasonings while acknowledging the existence of all states of the original evaluation system. The system consisting of t-acceptances, t-reasonings and t-preferences is the t-system. The system consisting ofthe t-system together with acknowledgment of the states of the original evaluation system is the ultrasystem. This is the basis of undefeated justification. Undefeatedjustification is coherence and justification on the basis of the contents of states of the t-system while acknowledging the existence of all states ofthe original evaluation system. That is my current theory articulated in 2000. I have attempted to explain reasonableness in terms of trustworthiness which leads to a loop in the system which I have argued is a virtuous loop rather than a vicious circle. My defense of this as well as the details is contained in the replies below but I should like to add some remarks on the subject here, even at the cost of repeating myself below, because the objection is one that often arises.

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CIRCULARITY

There are a number of philosophers who have objected to the circularity in my account of the application of the principle of trustworthiness and other principles in the explanation of justification. These principles are not part of my analysis or definition of knowledge and do not render the analysis or definition circular. I contend that the explanatory loop is a virtue and not a vice. I have drawn a distinction between explanation and proof. I have conceded that you cannot prove something to someone who doubts your conclusion by using it as a premise. That is not legitimate and all the rules of proof disallow it. But reasoning has different purposes, and only one of those is proof Another is explanation. If I seek a complete theory of justification for the purpose of explaining why I am justified in accepting each thing that I am, in fact, justified in accepting, then the theory, if! am justified in accepting it, must explain why I am justified in accepting it. I have no proof that one should seek for such a complete explanation of justification. I affirm only that it is my goal. Now some, Bender, for example, seem to think that I should try to prove to myselfthat I am justified, and he notes that I cannot do that with an argument that is circular, nor can I present any circular argument to myself that ought to convince me that I am justified I agree with him. I hope he will not be disappointed to find me so agreeable, but I agree with him that just as I should not expect to argue another out his doubts by a circular argument, so I should not expect to alleviate my own doubts by a circular argument. But suppose, as is the case, that I have no doubts about whether I am justified in accepting some obvious claims of common sense and only seek to explain why I am justified. Then I allege that some explanation is obtained by arguments that are circular and that circularity is necessary in a complete theory. The general point might be conceded and the particular forms I have used repudiated. Some of my critics suggest that rather than circularity of explanation one might be better advised to affirm that some beliefs or claims or whatnot are immediately justified. That is the strategy of the foundationalist. I have affirmed that some beliefs are justified without argument, or if you prefer, they are non inferentially justified. So where does a coherence theorist disagree with a foundationalist who claims that some beliefs are immediately justified? A coherence theorist disagrees about whether immediacy is a satisfactory explanation of why the belief is justified. Those who claim to be satisfied with such an explanation often have a reason for thinking special beliefs are immediately justified. That is a kind of background theory about immediate justifications. They have background beliefs, exactly what they are may vary, that explain why some beliefs, the foundations, are justified in themselves. But once that explanation is made explicit, they will be revealed as closet coherence theorists. They will assume that such beliefs are ones that are worthy of a

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person's trust without argument because they are successfully truth connected or for some related reason. Once that assumption is made explicit and the role of it in explanation of why we are justified in accepting those immediately justified beliefs is acknowledged, they will emerge in their true glory as philosophers who allege that justification can always be explained in terms of the background system of the subject, that is, they will emerge as coherence theorists. If they eschew that noble title, I would not dispute over the word. Call themselves what they may, their explanations, if traced far enough, will tie their explanation together in some virtuous loop rather than leaving immediate justification unexplained. If not, if they choose a theory of justification in which the immediacy of justification is unexplained, then we differ in our philosophical objectives. They are satisfied with unexplained first explainers, and I am not. I do not claim that they should have my goals of explanation, only that ifthey do, they will be led to the virtuous loop.

3.

REPLIES TO THE AUTHORS

3.1

Reply to Olsson

I am greatly indebted to Erik Olsson for his exceptional contribution to the study of my epistemology in this volume and wish to take this opportunity to thank him for arranging a conference in Constance on my work and for putting together this volume. I begin my reply to my discussants with Olsson's questions and contributions. Olsson raises the question of whether coherence depends on global features of the background system. It is useful to clarify my view on the matter. Coherence is a relation between a background system and a target acceptance. So, the global features of the background system are not part of the definition of coherence. However, one should not conclude from this definition of coherence as a relation to a system that no global feature of the system is relevant to whether a target acceptance coheres with a system. The relation of coherence of a target acceptance with an evaluation system consists of the system being able to meet objections to the target acceptance. That definition does not contain any mention of global features of the system, but it would be hasty to conclude from this that global features of the system are irrelevant to coherence. It may be that the capacity of a system to meet objections to a target acceptance depends on global features, and, indeed, that seems to me to be the case. The system cannot be so contradictory that it is useless for meeting objections to an acceptance. It would be useless, for example, if it were a deductively closed inconsistent system over the contents of acceptances. It would then contain the

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acceptance of the negation of every proposition whose acceptance was contained in the system. Nevertheless, an inconsistent system over contents of acceptances which is not deductively closed over contents may enable us to meet objections. This is so even though the deductive closure over contents of such as system would be useless. In a natural environment of acceptance, where even the most brilliant logicians are prone to having acceptance systems that are inconsistent over contents, it is essential not to impose deductive closure over contents. For such systems, but not their deductive closures, remain useful for providing coherence, justification and knowledge of the truth of some target acceptances. Another interesting question concerns whether my acceptance that p and my acceptance that I accept that p in a trustworthy way are functionally equivalent. I do not think that they are functionally equivalent. The point is that if a person accepts that he is trustworthy in what he accepts, then he will be ready to infer from his acceptance that p that he is trustworthy in his acceptance that p, but that is due to his acceptance of the proposition that he is trustworthy in what he accepts in addition to his acceptance of p. Suppose a person accepts that he is not trustworthy. That is something that he accepts. But having accepted that, he should not infer that he is trustworthy in accepting it. Would this really be acceptance, however? I think it might be. If I conclude that I am not trustworthy in what I accept, including my acceptance of that very claim, that I am not trustworthy in what I accept, I am still faced with the question of whether to accept or not to accept a given claim. And I might conclude that even if I am not trustworthy in what I accept, it is better that I put forth my best effort to distinguish between what is worth accepting and what is not worth accepting. In a mode of conscientious despair, I might, without thinking I am trustworthy, decide to do the best I can and accept various things. Any functional account will have some difficulty drawing distinctions between inferentially related functional states, but that is nature of functionalism rather than a special difficulty concerning the functional account of acceptance. I admit, however, that it is a problem. Now the question arises as to whether my new treatment of the Gettier problem will work. The example concerning Mr. Nogot and the Ferrari depends, I would suggest, on whether the subject can meet objections to the reasoning to the conclusion that someone in the class owns a Ferrari. I think I was unclear about what constitutes an unsound argument. An argument with a false premise or a false conclusion is unsound. To avoid the arbitrary character of simply stipulating the sound inductive argument must have a true conclusion, note that reasoning proceeds from premises that a person accepts to conclusions that the person accepts, and the false conclusion will not be t-accepted in the truth system, the t-system. There is another way of explaining why justification fails in the ultrasystem of the new book. It is an objection to the claim that someone in the class owns a Ferrari that Mr. Nogot does not own a Ferrari. That is an

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objection because the evidence supporting the latter claim is the evidence that Mr. Nogot owns a Ferrari. Can the objection be met in the ultrasystem? I would argue that it cannot be met because the truth constraints on that system preclude t-acceptance that Nogot owns a Ferrari, t-preference for accepting that Nogot owns a Ferrari over accepting that he does not, and any t-reasoning to the acceptance of the conclusion that Nogot owns a Ferrari. Olsson notes that the change in the conception of the ultrasystem is complicated by the introduction of preferences and reasonings in the evaluation system. That is, of course, correct. It is perhaps useful to note here why I have introduced these notions into the evaluation system. I introduced preferences to provide an explanation for the comparative evaluations of reasonableness. If a person prefers accepting p to accepting q and is reasonable in her preference, then it is more reasonable for her to accept p than to accept q. So, the reasonableness of preference can explain the comparative reasonableness of acceptance. The addition seemed to me important because it may be more reasonable for a person to accept p than to accept q even though the person accepts neither of them. Thus, it was not obvious to many how an acceptance system by itself could account for the comparative reasonableness of acceptance even with the assumption that the person was reasonable in what she accepted. I added reasonings to the evaluation system because it was unnatural to assume inferential deductive and inductive closure over the contents of the acceptance system to determine what a person knows. A person might know something if they were capable of deducing some consequence that they do not know precisely because the deduction is beyond their capabilities. What a person knows depends on how they actually can reason rather than on idealized closure relations. So, the addition of reasonings to the evaluation system is essential for the characterization of what a person knows. On the matter of skepticism, Olsson contends that there is a conflict in my views. Olsson contrasts the sophisticated common sense philosopher, which he says I am at the beginning of my book, with the moderate skeptic, which he says I am at the end of my latest edition. In part, he has misunderstood the sophisticated common sense philosopher, for he says, This moderately skeptical view should be contrasted with what I take to be Lehrer's common sense position, according to which we do have knowledge whether we are systematically deceived or not (if systematic deception is at all regarded a serious possibility). It should also be distinguished from radical skepticism, or at least one form of it, according to which we are ignorant whether we are systematically deceived or not. Lehrer, the common sense philosopher, is in conflict with Lehrer, the moderate skeptic. For, as I interpret the former, he is saying that we have knowledge even

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In fact, I have never held the position that we have knowledge even if we are systematically deceived. Truth is a necessary condition of knowledge on all the analyses of knowledge I have offered, and it follows that if we are systematically deceived, then what we accept is false, not true, and we lack knowledge. So, Lehrer as a sophisticated common sense philosopher assumed that we were not systematically deceived and, indeed, he assumed we know that we are not systematically deceived. I think that what misled Olsson is that he, contrary to Lehrer, holds the view that we cannot know that we are not systematically deceived, and thinking Lehrer must agree with that clearly correct view, altruistically attributes it to Lehrer. Olsson writes, Whether we know or not depends on whether we are systematically deceived or not. I think he attributes that to me as a moderate skeptic, which attribution, but he then continues,

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Since, as a matter of principle, we can have no empirical evidence either for or against systematic deception, I take it that Lehrer's moderately skeptical concept of knowledge will be useless in formulating empirical laws and theories. Now, there is where he gets it wrong about what I think and why he thinks there is a conflict in my view. I am a falliblist, so I agree that it is logically possible that we are systematically deceived, but I contend that we can be both trustworthy and reliable even though we are fallible. As a result, I think we can know that we are not systematically deceived, that we can have empirical evidence that we are not systematically deceived that provides us with personal justification and undefeated justification because we are not systematically deceived. We are fallible, admitted, and our evidence is fallible, admitted again, but that does not mean that we have failed. We have empirical evidence that we are not deceived, even though it is logically possible that we are deceived, for empirical evidence is inductive only and leaves open the logical possibility of error. The point put simply is this. There is a possible world in which we are systematically deceived. In that world the empirical evidence we would have that we are not deceived would be defeated because we are deceived and ignorant of the deception. In the actual world, the empirical evidence we have that we are not deceived is undefeated because we are not deceived, and we know that we

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are not deceived. It is wrong, though tempting, to conclude from the fact that empirical evidence does not logically entail a conclusion, that is, that there is a possible world in which we have the evidence even though conclusion is false, that, therefore, the empirical evidence fails to give us knowledge that the conclusion is true. As Olsson himself notes, an inductive argument, no matter how strongly it supports a conclusion inductively, does not have the salient feature of deductive validity, to wit, that it is logically impossible that the premises are true and the conclusion false. Our evidence that we are not systematically deceived and that the knowledge claims of the sophisticated common sense philosopher are correct is in no way refuted or undermined by the logical possibility that we are deceived. Lehrer the moderate skeptic alleges that, though we are fallible and systematic deception is logically possible, we have undefeated justification and knowledge, as Lehrer the sophisticated common sense philosopher affirmed, of common sense matters, including that we are not deceived. Some will say that since we would believe that we are not demonically deceived even if we were, our belief fails to track truth and, therefore, our evidence is inadequate. But that is a mistake. It is the mistake of thinking that no evidence can provide us with justification and knowledge unless the evidence logically entails what we know or at least that the belief for which it is evidence tracks truth. Inductive evidence, though it does not logically entail the conclusion known or insure that the belief for which it is evidence tracks truth, can provide us with undefeated justification and knowledge, nonetheless. Coherence combined with truth in the right way is sufficient for us to know and know that we know even though we are fallible. Hence I accept the consistent combination of sophisticated common sense, embracing knowledge, including that we are not systematically deceived, with moderate skepticism, embracing falliblism, including the logical possibility that we are deceived. We can reach across the gap of our fallibility to the goal of knowledge.

3.2 Reply to Sosa Ernest Sosa has examined some arguments I presented in Self- Trust against the thesis that epistemic properties supervene in a metaphysically necessary way on other properties. He is a brilliant philosopher from whom I have learned a great deal, perhaps more than I have acknowledged, and so I should like to acknowledge my debt to him and his philosophical writings on this occasion. His critical examination of my arguments convinces me that my arguments are not clear enough to convince anyone who thinks the supervenience theory is true. Part of the problem with presenting an argument against the general claim of supervenience is that it is a concealed existential claim, to wit, that there exists some naturalistic property on which a chosen

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epistemic property supervenes, and existential claims are notoriously difficult to falsify. In this reply, I hope to make it clear why I have never found the supervenience thesis at all appealing. The basic reason is that I am convinced that a relationship between epistemic properties and naturalistic ones is contingent and causal. Let me see what I can do to explain why I think the contingency thesis is true. Before doing so, however, let me note that this thesis is not essential to the coherence theory as I conceive of it at present. Coherence, which yields personal justification, is a relation to a background system of naturalistic states. The theory is not in any way undermined if the relation is metaphysically necessary. Moreover, even if the relation is one of metaphysical necessity, our knowledge of it, our acceptance and defense of it, remains a contingent matter. Nevertheless, I reject the supervenience thesis. Here is why. First of all, truth does not supervene on naturalistic states. Why? Because there are alternative consistent theories of truth. For example, they yield conflicting truth values for the proposition-all true propositions are true. On some consistent theories of truth, that is a true proposition, and on others it is not true. There are many other such examples. Possibility should track consistency. If the claim that x exemplifies F and not G is consistent, then it is possible that x exemplifies F and not G, and it is not necessarily true that if x exemplifies F, then x exemplifies G. Justification, one epistemic property, aims at truth and the avoidance of error in the particular proposition accepted. Truth does not supervene on naturalistic conditions because there are consistent alternative theories of truth conditions. Similarly, there are consistent alternative theories of justification. Take a radical one adapted from, though not adopted by, Descartes. Consider the skeptical theory that nothing anyone accepts in the world in which we live is justified, excepting, for each person, the acceptance of the cogito. The skeptic might or might not offer an argument for that claim. The usual arguments are ones that rest on the possible duplication of experience and cogitation by a powerful demon or scientist. Now I think that such an argument does not succeed, for I accept that there is no deception. The skeptic might agree that there is none but hold that we are not justified in accepting what we do because of the possibility of deception. We have different views about the relationship between what the naturalistic world is like and what we are justified in accepting even though we agree on what the naturalistic world is like. Is his position necessarily false? I do not see that it is. The skeptic is wrong, but contingently so. His view that we are not justified is a possibility, though his claim of skepticism is contingently false, and, indeed, we know it to be false. Skepticism is no impossibility. It is just false and known to be so. There are many replies to this argument. I consider two. One is that the possibility alluded to is epistemic not metaphysical. It means that, for all we know, the skeptic is right. But that is wrong. I know that skeptic wrong. His position is epistemically impossible but metaphysically possible. The second

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reply is that supervenience must hold, and we must be mistaken in thinking that the skeptical position is possible. It is like thinking that it is possible that identities do not hold, when it is necessary that they do. Well, why must supervenience be true? The usual reply is justification must be based on something. I agree it is based on something, but why must the basing relation be metaphysically necessary supervenience? Justification is contingently based. That is a typical way in which one thing is based on another. Here is my view about how justification is based, when it is, on naturalistic conditions, though, again, this view is not essential to the coherence theory. The basing is, as far as I can see, causal. Epistemic properties are part of the causal order. For example, sometimes a naturally formulated sequence of formulas proving a theorem in set theory makes the theorem evident to me. So sometimes a natural condition causes an epistemic one, and sometimes the causation runs in the other direction. Sometimes it is the evidentness of a proposition that causes me to believe it, for example, when the evidentness of the theorem makes me believe it. In short, I see no reason to deny that exemplification of epistemic properties are part of the causal order, causing and being caused by the exemplification of other properties. Can supervenience construed in terms of metaphysical necessity provide a place for epistemic properties in the causal order of things, however? Should we say that an object is caused to have epistemic properties if they supervene on base properties a thing is caused to have? Suppose that it is necessarily the case that some belief is evident if the belief has a base property. Suppose that, necessarily, if I believe that I am appeared to some way and am appeared to in that way, then it is evident to me that I am appeared to in that way. It does not follow from this that my believing that I am being appeared to in some way and being appeared to in that way caused it to be evident to me that I was appeared to in that way. So evidence is not, thereby, included in the causal order. To see that the conclusion does not follow, consider another example in which one thing is a necessary consequence of another. Something causes me to move by pushing me. If! move, then, necessarily, someone moves and 2+2 equals 4. Should we say that what caused me to move caused me to move and 2+2 to equal 4 just because that is a necessary consequence? I would not say so. In general, it is incorrect to claim that if something causes an object to have a property, then it causes it to have the necessary consequences of having that property. So, were it a fact that epistemic properties supervened on base properties, I would not say that something that caused a thing to have some base property, therefore, caused it to have the supervenient property just because that was a necessary consequence. There are replies to this objection I cannot deal with here. However, what is more important, and more crucial, is that supervenience cannot offer any explanation of causation in the other direction, that is, it cannot explain how something being evident to me, for example, how it being evident

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to me that I am appeared to in some way, could cause me to believe it. Consider also the earlier example. Suppose someone proves a theorem to me with such clarity that it is evident to me that it is a theorem. Might not the evidentness of this theorem cause me to believe it? There is no account of how on the supervenience theory. That theory is like epiphenomenalism in the theory of mind. Supervenience might offer a causal account, though I doubt that it can, of how something comes to have an epistemic property, but it can offer no causal account of how something comes to have a naturalistic property as a result of having an epistemic property. On the supervenience view, epistemic properties are causal danglers. They are impotent to cause anything. But, forgive me for appearing dogmatic, epistemic properties, contrary to what the supervenience theory suggests, are simply part of the causal order. Sometimes the evidentness is the cause of my believing something, just like my constructing a proof is sometimes the cause of the evidentness of the conclusion. The problem with the supervenience theory is that it supposes that the relationships between the epistemic and the non-epistemic are metaphysically necessary when, in fact, they are contingent and causal. The supervenience view has been popular in ethics, concerning ethical properties, but should we believe that moral properties are causally impotent danglers? Should we believe, for example, that wickedness is never the cause of death and destruction? Should we believe that the wickedness of a person never was the cause of contempt? The connections in both cases are contingent and causal. Epistemic and moral properties are part of the causal order. This does not mean, however, that they are reducible to anything else in the causal order. Their place in the causal nexus does not depend on their reduction to something else in the causal order. They have that place by their nature.

3.3 Reply to Greco I have long enjoyed my discourse over epistemology with John Greco. I appreciate his interest in these conversations and his acute philosophical reflections. In his current paper, he treats a counterexample of mine concerning Mr. Truetemp who has had a device implanted in his brain that produces true beliefs about his temperature. Truetemp does not know that the device is implanted, he is totally at a loss as to why these beliefs force themselves upon him from time to time. Moreover, even those who implanted the device in his brain without telling him do not know whether the device works because they implanted it without having tested it for functional accuracy. Mr. Truetemps beliefs about temperature are the result of a reliable belief forming mechanism. Now Greco agrees that Mr. Truetemp does not know and that the beliefs about his temperature are reliably formed. He, nevertheless, thinks that my account cannot explain this. His reasons are that he attributes forms of reasoning to

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Truetemp, to wit, that he is trustworthy in accepting what he does about his temperature, and so his accepting what he does is reasonable. My reply is simple enough. In my example, Mr. Truetemp has none of this reasoning because he does not think that he is trustworthy in believing what he does. This is my example, and I think the reaction of Truetemp is natural enough. Suppose you suddenly, for no reason you could discern, start having convictions about what your temperature is. Would you accept that you were trustworthy in believing these things without checking with a thermometer to see if you were right? You would not if you were reasonable. Moreover, whatever another might do in such circumstances, that is no objection to the logical possibility of the Mr. Truetemp counterexample. He does not accept that he is trustworthy in believing what he does about his temperature because he is smart enough to recognize that, having not confirmed the correctness of any of these spontaneous temperature convictions, he should not accept that he is trustworthy in spontaneously believing what he does about his temperature. So, there is an objection that Truetemp cannot meet, namely, that he is not trustworthy in believing that his temperature is so and so (when the device triggers it), for he does not accept that he is trustworthy. And he should not, for this is the kind of case that requires confirmation of thermometers for his beliefs which he has not undertaken. Greco seems to think that if I deny that Truetemp knows I will be committed to the conclusion that people lack knowledge in ordinary cases of perception. By why should I be committed to the conclusion that people lack confirmation for thinking that what they have accepted from the testimony of their senses is worthy of their trust? The confirmation is bountiful and supplied every day. I have no idea why Greco thinks it is psychologically implausible to think that people have access to information, to what they accept. I think he was misled by an example I gave of a person who lacked knowledge that something is the case but had knowledge of another sort, knowing how to get from one city to another. Part of the functional role of states of acceptance is to make accessible what one accepts for use in reasoning. They have access to what they accept, including the trustworthiness of what they accept in perception, even if they do not sit about, as a philosopher might, reflecting on their trustworthiness. Experience, and what they accept about the truth of what they perceive, makes the trustworthiness of perception transparent to them. Of course, such a reply might seem circular to a foundation theorist, but a coherence theorist, at least this one, will reply that general assumptions of trustworthiness and reliability are confirmed by the positive instances of true acceptances as measured against the negative instances of error. In a sentence, Truetemp, as I conceive of him, does not accept that he is trustworthy in his spontaneous temperature beliefs, because he has not confirmed that any of them are correct. But he does accept that he is trustworthy in his commonplace perceptual beliefs because he has bountifully confirmed the truth connected reliability of such beliefs. Indeed, Greco quotes me concerning Truetemp, "He

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has no idea whether he or his thoughts about the temperature are reliable." So I find it a mystery why he should think I would allow that Truetemp in my example would assume that he is trustworthy in accepting these thoughts about the temperature. My Truetemp example suffices then to show that reliability is not sufficient for knowledge. I concede that it is necessary. In a similar way, given what Greco concedes, he should admit that an adequate account of agent reliability will have to bring in background considerations about how the agent views himself and how what he accepts coheres with these views so that he is in a position to answer objections to what he accepts. Such agent causality reliablism will adopt coherence as a condition of knowledge, and such reliablism may be even be true.

3.4 Reply to Kvanvig Kvanvig argues convincingly in support of my examples to show that a person can be justified in accepting that p on the basis of evidence that does not cause or causally sustain the person's belief that p. What is important is that the person know the evidence and understand the justificatory relationships between the evidence and the acceptance of p, which, on my account, means that the person understands how to use the evidence to meet objections to p. A person may understand perfectly how to use evidence to meet objections to accepting that p without the evidence having played any causal role in the formation or sustenance of belief. The crucial role of evidence is the adequate defense of acceptance. I am now inclined to distinguish more sharply between acceptance, a higher order positive evaluation, and belief, a first order functional state. Acceptance is also a functional state, one that has a functional role in reasoning, and, more specifically, in meeting objections to yield justification. What convinces me that the gypsy lawyer and the racially prejudiced doctor have knowledge is that they accept, not just believe, the claims in question. The positive evaluation of those claims is backed by their capacity to meet objections to their claims, that the client is innocent, in the one case, that the disease is genetically specific to the race, in the other. They can do as well as anyone on the basis of the background information, the evidence, they possess. Though I appreciate the defense that Kvanvig supplies, it might be useful to consider an objection that could be articulated in terms of the account I have offered and which may reveal the power of the account to explain the contrary intuition. Consider the prejudiced doctor. Is it not an objection to what she accepts that she believes what she does in a way that is not trustworthy? She believes what she does out of prejudice, after all, and that is not a trustworthy way to believe things. This must be admitted, and it is the basis, I conjecture, of

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the conclusion drawn by others that she lacks knowledge. But the conclusion is incorrect, and why it is incorrect is also explained by the theory. The explanation is that the doctor can meet the objection by neutralizing it. She is in a position to admit that she believes what she does out of prejudice, that is, she believes what she does in a way that is not trustworthy, but to neutralize the objection by adding that the evidence that she knows to be true shows that the disease is genetically specific to the race. So far, it appears that her background system enables her to meet the objection that the way in which she believes things is not trustworthy. Now, however, a somewhat deeper objection arises, namely, that the doctor is not intellectually trustworthy because of her prejudice which must be admitted to be an objection. Can she meet that objection by neutralizing it? What can she say? It seems to me that she can admit that she is not intellectually trustworthy because of prejudice but that she understands in a trustworthy way that the evidence she knows to be true shows that the disease is genetically specific to race. Some will refuse to accept this reply as true because they will think that no trustworthy understanding is compatible with prejudiced belief. Others will think her reply is just. I think it is just. My reason for thinking so is based on my distinction between the first order state of belief and the higher order states of evaluation which include acceptance. Belief is driven by nature, and is not immediately responsive to reason or evidence. Acceptance is the positive evaluation in terms of evidence and is responsive to it. It is acceptance, consequently, that I take to be what is necessary for knowledge and which, when backed by undefeated justification, converts to knowledge. People may be trustworthy in their understanding of evidence and how to employ it in evaluation when belief stands fixed and inflexible before the court of evidence. It is not only the prejudiced doctor and gypsy lawyer whose belief formation and retention is sometimes unresponsive to reason. The best we can do is to evaluate belief, accept it or reject it in a trustworthy way as we consider the evidence, and that is the way to knowledge. To expect that we shall cease to believe what he reject in a trustworthy way is, unfortunately, naive, and to expect that we shall always come to believe what we accept in this way is also naive. I confess that I did not appreciate how belief and acceptance may separate. Contrary to what I said, we may accept something without coming to believe it. Belief sometimes lags behind the positive evaluations of reasons, or worse yet, ignores them. One final question might be raised by the distinction between acceptance and belief. It might be asked whether acceptance on the basis of evidence requires that the evidence cause or causally sustain acceptance. As in the case of belief, evidence or our attitude toward it, may cause us to accept what we do, but it need not. Acceptance is positive evaluation and understanding ofthe nexus, the relationship, between evidence and what is accepted. Evaluation suffices for acceptance. However, as I note in reply to Stewart, there remains a question

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about whether a person can be trustworthy in what he accepts when, though he understands the relationship between evaluation and evidence, this understanding does not have any causal influence on what he accepts. If the answer is negative, then someone might claim that he lacks knowledge because he is not trustworthy in what he accepts. I am not sure what to say about such a case. I remain content to say that intuitions about whether a person knows who does not accept what he does because of his scientific understanding of the evidence will depend on whether one thinks that the person is trustworthy in what he accepts. That is what my theory would predict, and I remain content with the conclusion that there is genuine disagreement about whether a person is trustworthy in what he or she accepts when understanding of the evidence is not causally efficacious in evaluation and acceptance.

3.5. Reply to Todd Stewart It is a pleasure to reply to Stewart's admirably clear discussion of the example of Raco who forms a belief in a prejudiced manner and then gains scientific evidence as a skilled scientist that favors what he believes in prejudiced manner. Raco appreciates and understands the scientific evidence perfectly and accepts in a scientific manner what he believes in only a prejudiced manner. As a result, he knows that what he accepts on the scientific evidence is true. What about the role of causation in his knowledge? I am not so silent as Stewart maintains about causation, even in application to this case. In my latest work, I have claimed that for a person to have knowledge, he must turn out to be correct in what he accepts because he has proceeded in a way that is worthy of his trust. Now, with this qualification, the Raco case becomes interesting. Is Raco correct in what he accepts because he has proceeded in a scientific manner in considering the evidence? I would say the answer is affirmative. He is not correct because he believes something in a prejudiced manner but because he accepts it in a scientific manner. So when I reflect on the condition concerning acceptance that Stewart carefully formulates, I agree. There remains a subtle issue about proceeding scientifically, however. I distinguish between belief, a first order state, and acceptance, which I consider a metamental state arising from positive evaluation in terms of evidence. Now Raco has reasons for acceptance which provide a kind of scientific certification of the prejudiced belief. Raco' s acceptance that p on the basis of the scientific evidence is what gives him knowledge. This knowledge depends, in part, on his being correct in accepting that p because he has based his acceptance on the evidence. Now the question is whether the scientific reasons need be Raco' sown reasons, as Stewart puts it, for the scientific certification of the belief, that is, for the acceptance of the initially prejudiced belief. Understanding the evidence and proceeding in a trustworthy way in deciding what to accept on the evidence

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appears not to be sufficient. If understanding of the trustworthy way of deciding what to accept does not cause him to accept what he does, then he does not accept what he does because he based his acceptance on the evidence. In that case, there is an objection to the way he has proceeded that he must meet. It is that he is not trustworthy in accepting that p in the way he does. So the problem is that the causal connection between understanding the scientific evidence and accepting what he does is a necessary condition of his being trustworthy in what he accepts. If his positive evaluation and acceptance of p float freely above his scientific evaluation of p, then he is not trustworthy in his acceptance ofp. That is the difficult objection that seems to me to lie behind or around Stewart's objection about the issue of whether the justifying reasons are his own. And that is a perplexing issue. My original argument about such cases starting from the case of the Gypsy Lawyer and proceeding to the case of Raco was based on the assumption that what makes us believe things is pretty much beyond our ken and control and that knowledge, therefore, cannot depend entirely on what makes us believe something. A perfect understanding of evidence and the most careful use of it often fail to amend belief. But I now hold that it is not belief but acceptance that is the condition of knowledge. In short, we can be of two minds about something, believing it in the first order mind, for example, and accepting the denial of it scientifically. That is a functionally discomforting state of two minds but not necessarily a dysfunctional one. The distinction naturally raises the question put by Stewart. Doesn't acceptance, if not belief, have to be based on reasons that are my own in the sense that I accept what I do because I have those reasons for accepting it in order for me to be trustworthy in what I accept? If you think that trustworthiness in what one accepts depends on the right sort of causal connection between evidence and evaluation, you will conclude that a person is not trustworthy in some modification of the Gypsy Lawyer and Raco cases in which acceptance, like belief, is not causally connected with the scientific evidence the person has and appreciates. If you think the causal connection is not essential, you will think they could be trustworthy in what they accept anyway. If you think the first, you will think they have knowledge, if you think the second, you will deny this. So what do I think? Stewart has created doubts in my mind, not about the original cases concerning belief, but about ones in which the defective causal relations shed doubt on whether the person is trustworthy, or if the person is trustworthy in what they accept, whether they are correct in what they accept because of it. My theory about the relationship of trustworthiness to knowledge predicts and explains this divergence of intuitions. To be candid, I place less weight on my own intuitions as a result of Stewart's arguments. Intuition provides data for testing theories, but when intuitions divide, the test is degraded. It seems best in such cases to let theory construction be determined by other considerations. However, for what it is worth, I think that Raco is trustworthy in what he accepts about the disease on the scientific evidence. I

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think that he is correct in what he accepts because he is trustworthy in the way he has accepted this, and, to be candid, I think that his reasons, his evidence, are his own reasons for accepting what he does. What his reasons are for believing what he does about the disease are another matter, but one that does not matter for determining whether he knows. He knows.

3.6. Reply to Halbach I have greatly profited from Halbach's talented criticism of my work. I discuss the issue of consistency in reply to other papers. I agree with what Halbach says, however, in reply to those who claim that consistency is inaccessible, that is, I think he is right in his claim that these arguments are inconclusive. My only disagreement with Halbach is that I disagree with a claim I once accepted to the effect that all justifications are defeated on the basis of an inconsistent system. This will only be plausible if the system is deductively closed in standard logic. Suppose, instead, that it is an ordinary system with relatively little deductive closure. How a person would defend a target acceptance against objections will depend on how the person reasons. A person might be more like a relevance logic reasoner than a standard logic reasoner closing over the deductive consequence relation, or, what is more likely, may be influenced by what they would consider a natural reply on the basis of the background system. Natural reasoning in defense of something on the basis of what one accepts does not require that one first deductively close on the contents of the background system in standard logic, even if one can. In general, that would not be a reasonable way to proceed because natural acceptance systems will be inconsistent, even if we seek consistency, and closure will render them useless for epistemic purposes. With that said, however, I do want to make it clear that I think what Halbach says against arguments denying that consistency is accessible is correct. Though I now think that acceptance systems that yield justified acceptance and knowledge may be inconsistent, I still take consistency as an objective of the life of reason and consider it important to show, as Halbach has, that attainment of the objective is not generally inaccessible.

3.7. Reply to Ross I found the essay by Ross on the Lottery Paradox to be a valuable and perceptive contribution to the subject, and the way in which he has applied my theory is exceptionally illuminating. His basic claim is that on my theory of justification based on beating and neutralizing of competitors, or, as I reformulated it in my latest version, of answering or neutralizing objections, the

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objection that can be raised to accepting an arbitrary losing ticket hypothesis in a lottery of three or more consecutively numbered tickets can be neutralized. So, contrary to what I claimed, the subject might be justified in accepting the negative lottery hypothesis. Suppose the lottery has a thousand tickets, and I consider whether I am justified in accepting the hypothesis that the number one ticket is not the winning ticket. I have pointed out that the objection that claim that the number two ticket is not the winning ticket, if assumed, reduces the probability and, in such a case, the reasonableness of accepting that the number one ticket is not the winning ticket. Assuming that the number two ticket is not the winner eliminates one way in which the hypothesis that the number one ticket is not the winning ticket could turn out to be true, namely, by the number two ticket winning. Moreover, the subject is not in position to claim that it is more reasonable to accept that the number one ticket is not a winning ticket than to accept that the number two ticket is not the winning ticket. So the competitor or objection cannot be beaten. But can the competitor or objection be neutralized? I said, without explanation, that it cannot be neutralized. Ross suggests that it can be neutralized. It is not less reasonable to accept the conjunction that the number two ticket will not win and that the one ticket will not win, than simply to accept that the number two ticket will not win, he contends. As a result, the conjunction neutralizes the competitor or objection that the number two ticket will not win, for the conjunction is not a competitor or objection to the claim that the number one ticket will not win. Ross notes that, though the objection is more probable than the conjunction, it does not follow that is more reasonable because the conjunction has more content and is more informative. So, the question is whether the neutralization succeeds. Is it as reasonable to accept the conjunction that the number one ticket will not win and that the number two ticket will not win as to accept simply that the number two ticket will not win? Is it as reasonable to accept that neither ticket will win as to accept one of them will not win? Now, if it is just a matter of gain of content versus loss of probability, one might argue that the symmetry between the gain of one and the loss of the other makes it an even trade. One is not obliged to adopt that symmetry view of the epistemic value or utility, though it is tempting and did once seem correct to me. I am now disposed to think that would be a mistake, that is, I think that there is more to the reasonableness of what one accepts than the probability and content, as Ross notes. For there are systematic considerations to be considered, and those considerations require that one consider where the reasoning of adopting such neutralization would lead us. Where would it lead us? It would lead us to concluding that adding to the conjunction that the number three ticket will not win, though it would reduce the probability would also increase the content, and so on for the claim that each ticket will not win until we found ourselves accepting the conjunction affirming for every ticket in the lottery that it will not

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win. Of course, one is not obliged to adopt that view about what is reasonable, and one might find a justification for stopping at some point. But the point is that one needs a justification, as Ross would agree. Now, however, one can see the advantage of the account of justification in terms of neutralization, for it allows us to explain a difference in views, a difference in intuitions, in the case of the lottery. Some are inclined to affirm, in spite of my reasoning to the contrary, that they are justified in accepting that the ticket they hold in a large lottery will not win, and, indeed, that they know the ticket is not the winning ticket. Others hold another view and have a different intuition. The difference, I suggest, depends on whether their views about reasonableness allow that the competitor or objection that it is just as reasonable, and on the same grounds, to accept that each other ticket will not win (including, of course, the ticket that will, in fact, win) can be neutralized. So, in fact, I take it to be an advantage of my account that it explains the views about justification and knowledge that differ from my own in terms of whether the neutralization succeeds. The questions Ross poses concerning what is reasonable raises issues about impartiality and consistency. My view is that it may be reasonable to accept an inconsistent set of statements or even a complicated statement that is self-contradictory, for, as I have noted before, it may be reasonable, though false, to accept that such a set of statements is consistent. Our most reasonable efforts to be consistent can fail. We are fallible about consistency. This does not mean, however, that consistency is not an objective of rationality. I think it is. Similarly, there may be cases in which one is reasonable to accept a set of statements that are not accepted with impartiality. For, it may be reasonable, though false, to accept that one has accepted what one has with impartiality. Our most reasonable efforts to be impartial can fail. We are not infallible about impartiality either. Moreover, our objectives contain internal stress, for example, our objectives of not accepting what is false and our objective of accepting what is true. So there are multiple objectives that may come into conflict as we seek to satisfy them all. What is the reasonable policy? It is to avoid any general strategy that we know with certainty will defeat our objectives. That means we should avoid any strategy that we know with certain will lead us into inconsistency or impartiality. We may not be able to avoid them, since we are fallible in our objectives, but that does not mean that it is reasonable to adopt a strategy that we are certain will lead to failure. We do not have to be infallible to be reasonable, but we should seek to avoid the certainty of failure in seeking the objectives of reason in order to be reasonable. That is why I prefer to forego accepting that my ticket will not win the lottery. If! do accept that my ticket will not win the lottery, I am certain I will either fail to be consistent or fail to be impartial. I probably will fail anyway, but I do not want to make that certain. Finally, what about the claim that viewed with sufficient generality, acceptance is always a lottery, at least with respect to the totality of what we

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accept, and, therefore, we cannot avoid being either inconsistent or partial? As I noted, being fallible as we are, it is probable that we shall fail from time to time and fall into inconsistency or partiality or perhaps both and worse. But I see no proof ofthis that is convincing. At one time, following Carnap, I thought every statement was logically equivalent to state descriptions or disjunctions of state descriptions or, for the infinite case, set-theoretic equivalents of those. If we restrict ourselves to logic and descriptive terms, that may be so, but when we consider the evidence of statements, how evident and reasonable they are, I do not see any convincing argument for the symmetry between lotteries, where only probability comes into the picture, and general descriptions of the world. Those general descriptions of the world may have differing features of evidence, which I now think are part of the nature of things, that do not yield the symmetries of reasonableness of acceptance characteristic oflotteries. I prefer, given this view, to pursue the objectives of reason in a way that gives me a chance, however small, of succeeding in attaining those objectives. If another is so impressed by hopelessness of this as to become indifferent to them, I can only remark that the pursuit of an ideal, even if the attainment of it appears hopeless, may improve our performance in the pursuit of it whatever the ultimate outcome.

3.8. Reply to Cross Cross has constructed a formal account of inductive inference based on a simplified and formalized treatment of components of the theory of justification that I have proposed. I greatly appreciate the contribution that he has made. I consider plausible and important the possible extension of my account to paraconsistent logic. It is important to examine the implications of dropping consistency as a requirement, for that is what I now consider necessary, and to construct a dynamic account to better understand the implications for change of justification. I need to reflect on the implications of what Cross has done more fully. Though he has imposed a consistency requirement and concerned himself with the content of states of acceptance rather than the states of acceptance, he has proceeded in a manner that strikes me as closer to the spirit of my theory of justification than others who have introduced such simplifications. Taking the primitive notion of comparative epistemic reasonableness as the basis of justification in the way he does seems illuminating to me. I look forward to studying the implications of his insightful and original treatment more fully than I can now find time to do.

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3.9. Reply to Spohn Spohn, a philosopher I have long admired, has obtained an interesting and important result by applying ranking theory as an interpretation of preference. I greatly appreciate the interest he has given my work and the formal results he has obtained. He obtains the result that on my account knowledge reduces to acceptance given the role of preference in my evaluation system. Spohn recognizes that his interpretation of preference is a formally regimented and, consequently, idealized conception of preference. He concludes that his reduction is not one I would accept as a friendly amendment. In that, he is right. So, my initial response is what he would expect, namely, to regard the treatment of preference in terms of ranking theory as a reductio of that interpretation and to thank Spohn for making it so clear that I should not make the mistake of interpreting preference in terms of ranking theory. However, there is more to be learned from what Spohn has done, and more philosophy hangs on the details of his treatment than a philosopher might suspect. Spohn treats "s accepts that p" and "p" as having the same role in the acceptance system and preference system. That won't do, and it is important why it won't. First of all, it is obvious that having started out with this equivalence, acceptance and truth will also turn out to be equivalent. Another critic, Manning, objects that from acceptance of p, it is always illegitimate to conclude that p, while Spohn begins by treating acceptance of p and p as having the same role in justification on my view. I reject both the Manning and the Spohn view for the same reason. Sometimes it is legitimate to conclude from the fact that a person accepts something that what he accepts is true, sometimes it is reasonable to reason from S accepts that p to the conclusion that p, but not always. Whether the conclusion is reasonable for the reasoner depends on what the person accepts about the trustworthiness of S and on whether the person can meet objections to concluding that p. The objections include, for example, that S is not trustworthy in accepting that p, that S cannot tell whether or not p, that there is other evidence that p is false, and so forth. In short, concluding that p from someone's acceptance that p minimally requires that the conclusion coheres with the other things you accept and what you accept about S. So, when Spohn identifies acceptance of p with p, he implicitly eliminates the role of justification, that is, the role of meeting objections, and, not surprisingly, on his treatment, it turns out that there is no role for justification. Thus, I am grateful to Spohn for drawing out the consequences of a restriction that I had placed on the background system, namely, that it consist of acceptances of the subject rather than the things that the person accepted. He has shown that dropping the restriction eliminates the role of justification. I find that to be a very useful result to have before us. The next point in his treatment with which I would take issue at this point is the imposition of consistency and closure. When we begin thinking about

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coherence, we naturally conclude that consistency is a condition of coherence. We also naturally think that deduction is the ideal of reasoning and that deductive closure is the ideal of deduction. That is natural, but it won't quite do. Spohn forces my hand in the matter by his result. First of all, much of the cogent reasoning of science and everyday life is not deductive. So when I used reasoning as a component of an evaluation system, the system for evaluating coherence, I did not intend to restrict reasoning to deduction. Reasonable conclusions may be drawn though they cannot be deduced. Inference to the best explanation is not deductive. Inference from a capacity to the successful exercise of it is not deductive. In particular, the inference from 1. S is trustworthy in what S accepts and S accepts that p

to 2. S is trustworthy in accepting that p

is reasonable, but it is not deductive. The claim that a person is trustworthy in what she accepts, on my interpretation, is a claim about a capacity to be trustworthy, which can fail to succeed in a given instance, and similarly, the inference from 3. p coheres with the evaluation system of S

to

4.p is reasonable, but it is not deductive either. However, the most important change in my own views has been the rejection of consistency as a constraint on a background system that yields justification and knowledge. I began by assuming it was a necessary constraint. Most recently, I have rejected it as a constraint and, therefore, depart from the tradition that takes consistency as a primary constraint on a background system used to account for knowledge. The explanation for my abandoning consistency as a constraint on the background system is that a person may reasonably but incorrectly accept that a system is consistent and know a good deal on the basis of such a system. Consider Bertrand Russell when he accepted naiVe set theory in the development of logicism. He reasonably but incorrectly accepted that his set theory was consistent and accepted his set theory. It was inconsistent, and so his background acceptance system was inconsistent. Obviously, he did not know that his set theory was correct, for it was not. But, equally obviously, Russell

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knew that he was Russell and much else beside on the basis of his background system which, because of what he accepted about set theory, was inconsistent. We know things on the basis of inconsistent background systems, that is, on the basis of background systems in which the claims that we accept are inconsistent as a set. Moreover, it is obvious, once inconsistency is allowed, that deductive closure is not harmlessly imposed but epistemically disastrous. If Russell had deductively closed his inconsistent system, he would have included the claim that he was not Russell along with the claim that he was and would have fallen ignorant about even the simple fact that he was Russell. Deductive closure is not harmless, however, even when a background system is consistent. A reasonable person, one who is interested in proceeding in a reasonable way, must constrain the impulse to deduce. A reasonable person will be ready to consider objections to what she considers and to consider the acceptance of new information, in short, she will be ready to revise. Now, the actual person, unlike the idealized one, is hindered rather than assisted by increasing the size of her acceptance system. So, leading the life of reason, the model person will not deductively close her system. She will, instead keep the system as simple as she reasonably can to facilitate a survey of what is contained therein. To be sure, there is a conflict within reason between keeping her system simple and deducing the consequences thereof in dealing with revision in a reasonable way. Ifshe does not deduce the consequences of what she accepts, of some simple representation of the content thereof, she may fail to note that what she accepts is inconsistent with some new information and fail to revise when reason calls for it. Consistency, though not a reasonable constraint on a background system, is, nevertheless, a desideratum, and deduction of consequences is important for noticing inconsistency. I am afraid that the upshot may seem disappointing to Spohn. Consistency is a desideratum but not a necessary condition for a background system that generates reasonable acceptance,justified acceptance and knowledge. As a result, deduction, however important it may be in the life of reason, can be harmful to reasonable revision of a background system when used to close a background system which is inconsistent, though effective for generating knowledge, and render it useless for generating that knowledge. As I have illustrated elsewhere, moreover, there are cases in which a background system that is inconsistent may be more reasonable to accept than any consistent subset of it because the choice of a subset would be arbitrary and would ignore important information. So how can coherence generate justification and knowledge when the background system of acceptances is inconsistent in terms of the accepted claims? It is because coherence is not a property of the background system but a relationship of the background system to some target acceptance. The target acceptance coheres with the background system just in case the background system suffices to meet all objections to the target acceptance. The inconsistency

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of a background system may permit such coherence, provided it is not deductively closed. Consider Russell again. He knows he is Russell. It is not an objection to his acceptance of the claim that he is Russell that his set theory is inconsistent or that his acceptance system is inconsistent for that reason. I suspect that, like Russell, most of us have inconsistent acceptance systems, but we know many things on the basis of such systems. The essay by Spohn is a technically brilliant and useful one. It permits me to ponder where I should separate my account of preference from that provided by ranking theory and how I might modify such an account so it would behave in a way that I find congenial. In conclusion, I shall speculate on the issue of providing rigorous theorizing. I suspect that rigorous theorizing about justification may reasonably depart from the idealization of a consistent and deductively closed system in order to remain closer to cognitive structures which we realize. This is not a rejection of formal logic or mathematical methodology grounded in consistency and closure. It is, instead, a recognition of the fact that our cognitive structure, as it comes to focus on consistency and closure of consequences, departs from both in ways that are essential to the functioning of that structure. Consistency is one desideratum of reason, but there are others, and the weight given to consistency must be limited or the use of reason will suffer. If one were only concerned to remain consistent in what one accepted, one could attain that goal by accepting only the cogito and venturing no further. For whatever narcissistic gratification that might provide, it would fall short of the life of reason. Once one departs from the safest certainties, once one uses reason to obtain explanation and understanding, one will, from time to time, fall into error and inconsistency. A rigorous theory of rational acceptance and knowledge, in short, of the properly conducted life of reason, must concern itselfwith the reasonable management of error and inconsistency in our cognitive structure rather then the idealized extirpation of them. What I have written in reply to Spohn is not intended as a criticism of what Spohn has written. I admire what he has written. I am, instead, requesting that he reexamine preference over acceptance, preserving the distinction between acceptance and what is accepted, and dropping the global constraints of consistency and closure on the dynamics of belief revision.

3.10. Reply to Wagner The formal result that Wagner has contributed in his essay reminds me how much I enjoyed our previous collaboration even though we have gone in somewhat different directions subsequently. The book that we wrote together is one that I continue to find gratifying and continue to use in my philosophical writings. I am very grateful that we were able to collaborate on the book together

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and that I was able to benefit from his exceptional mathematical and philosophical talents. His focus on probabilism in the present paper affords me with the opportunity to explain how I see the connection between our work together as well as his present work and the theory of knowledge. A number of philosophers, social scientists and mathematicians have tended to see theories of categorical or rational acceptance and theories of degrees of acceptance or personal probability as competing explanatory theories, Richard Jeffrey, most especially. On the face of it, they are complimentary rather than competing for the simple reason that degrees of acceptance or probability would be a determining factor in categorical acceptance or rational acceptance. Looked at from the standpoint of cognitive psychology, probabilistic vectors are plausibly regarded as a component in categorical decisions whether those are decisions to act in the external world or to arrive at some internal choice, for example, to accept something. The assumption that probabilism competes with a theory of rational acceptance results from adding to probabilism and Bayesianism the addendum, and that is all there is to human thought, action and rationality. The addendum seems to me to be false. The addendum is supported if one accepts behaviorism, but that is not something I would accept. So, I think that probabilism has an important contribution to make, but that is not all there is to it. Science as well as everyday life is rife with categorical claims expressing supplemented with impartial acceptance. These must, of course, be consideration of objections to those claims and the attempt to meet those objections in an impartial manner to avoid dogmatism and error. That is part of the structure of rational thought and discourse, and that structure is what I have sought to refine in the theory of justification and knowledge I have articulated. So why do I think that probability theory is not adequate to model all this with only minor modification? The reason is grounded in our psychology, however admirable or deplorable that might be. We do accept some claims and reject others. But there is a theoretical point of interest, namely, if we seek to avoid error in what we accept considering only probability, then we should take no risk in what we accept and restrict ourselves to what has a probability of one. But we do not want to do that in science or everyday life. So, something other than probability is entering into our rational decisions of what to accept. Some have thought that informational content is the other factor, and I was inclined to concur, but I now think that more systematic considerations, systematic explanatory power and coherence, for example, are important as well. Moreover, just as in practical matters, we ultimately choose to accept one action or another, so in intellectual matters we choose to accept one claim or another. Whether the choice is practical or intellectual, we avoid dogmatism by remaining open to reconsideration, but there is an advantage to making a choice, and choice is categorical, even if subject to revision and reconsideration. The advantages of choice are illustrated very nicely by the choice of Bayesian ism by those who

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have developed the theory. Acceptance of the theory motivates them and drives their creative construction. And that is how we work. What is the contribution of probabilism to my theory of knowledge? One factor in comparative reasonableness of acceptance, which corresponds to reasonable preference over acceptance, is probability. Comparative reasonableness of acceptance cannot be equated with degree of probability because that would lead us to the result that it is always more reasonable to accept the more probable hypothesis, to stick to the data rather than to extrapolate to some unifYing explanation of it. The data will be more probable than the theory which, like all theories, has a high probability of turning out to be in error. Nevertheless, probability is an important factor, because it gives us a measure of our risk of error. We do seek to avoid error. Whatever other objectives we have and no matter how much weight we give to those objectives, we must give some weight to avoiding error, and, hence to probability. Moreover, as Wagner notes, if the superior theory of probability proves to be one employing nonadditive upper and lower probabilities, the advantage of such a theory is that it allows us to employ and socially aggregate a wider base of information, including consensual information. Such probabilism imposes an important constraint on reasonableness. Moreover, probabilism has provided us with an illuminating account of the dynamics of probability change to which Wagner has brilliantly contributed. It remains an open question in my mind how much of the story of reason, justification and knowledge can be accounted for by the development of probability theory.

3.11. Reply to Van Cleve The essay by Van Cleve on my account of Reid seems to me to be well reasoned and correct as is characteristic of his exceptional work. He raises some questions, but he then turns to providing answers which are, for the most part, just the ones that I would provide. There are a couple of questions to which, it appears, he would like an answer from me. The first concerns positioning of principle 7, the principle that our faculties by which we distinguish truth from error are not fallacious. Though Reid says it is in a way prior to all the rest, he does not put it first. Why? I surmise, without much confidence, that there are two answers. The first is that since the principle refers to our faculties, saying that they are not fallacious, he wanted first to give some examples of such faculties. The second, related to the first and favoring my interpretation, is that the faculty by which we judge the truth of principle 7 is a faculty by which we judge faculties, and, therefore, it seemed proper to list it after listing some principles of other faculties. Consciousness, perception and memory are, after all, paradigm examples of faculties. I do not take this to be very decisive, since there are principles that follow 7 as well, though he may have had less confidence that

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each of the principles that follow 7 would be recognized as principles of faculties. I am not prepared to make too much of this consideration. I really think that he may have been somewhat casual about the order and only sought to give some examples of principles of what he thought the reader would acknowledge to be trustworthy faculties before formulating a principle about them all to that effect. The order may be governed more by an attempt to convince the reader than by considerations of metaphysical priority. Van Cleve raises a question about the modal status of the principle, especially as it applies to itself. It is clear that Reid thought the principle was contingent as he lists it under first principles of contingent truths. Moreover, I think that the principle is the principle of a faculty by which we can judge faculties, and it is a contingent truth that this faculty, which enables us to judge the veracity of other facuIties, allows us to judge itself as well. A faculty is an original capacity, and we might not have had such a faculty. It is a contingent truth that we do. Van Cleve asks what makes the principle that our faculties are not fallacious, or, alternatively, that the principles of our faculties are truthful, itself true. I think Reid's answer would be the character of the faculties, including the faculty of judging principle 7 itself, which nature has given us. We might not have had such a capacity, but we do. We have it by our nature. That is a contingent fact and not a necessary truth. Now Van Cleve notes that the general first principles as well as their instances are considered by Reid to be first principles, evident in themselves without need of the support of reasoning. Thus, whatever priority principle 7 has in the first principles is not a priority ofreasoning. Moreover, Reid says that first principles do not admit of proof by reasoning any more than they require it. So what can the special status of principle 7 be? Reid says that the principles hang together like links in a chain, that one must be prepared to pick up them all if one picks up any of them, which suggests a coherence theory, but he also insists that the general first principles as well as their instances have an evidence that is immediate and not derived from reasoning, which suggests a foundation theory. So which is it? I think the answer is not hard to find. It is that we must distinguish between the explanation of evidence and the generation of it. Principle 7 may explain why perception yields truth and is not fallacious. It is one of our faculties, after all, and by principle 7 our faculties are not fallacious. But the evidence of a perceptual belief, that I see something red before me, for example, does not depend on the use of such reasoning. Can such reasoning contribute to the evidence of my belief that I see something red? According to Reid, the belief has all the evidence it can have, it is as evident as it can be, before such reasoning is brought to bear upon it. It admits of no more. Reid, innocent of contemporary disputes, would hold that the first principles, though they depend on one another, are immediately evident. It may seem an odd position to one seeking for the simplest view. Reid, however, mistrusted simplicity as a guide to truth. A kind of intellectual modesty and natural piety led

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him to think that the truth about the world and ourselves should not be assumed to conform to our wishes for simplicity. That may also have been one reason why he did not seek to reduce all his principles of contingent truth to principle 7 or any other for the sake of simplicity. I am much indebted to Van Cleve for the clarity he has brought to these issues in his discussion and hope that I may have done something by way of answering his inquiries. I acknowledge that I have not replied to all of them, and that is only because I do not have the answers to them all. Van Cleve provides us with an interpretation of Reid of great cogency, and where we disagree, I am inclined to find the textual evidence inconclusive. I find the multiple interpretations of Reid to be a consequence of both the subtlety and modesty of Reid. When his intellect could take him no further, he fell silent.

3.12. Reply to Mattey Mattey has given a brilliantly lucid and clear account of my views on acceptance, reasonableness and the principle of trustworthiness. His remarks reveal his talent as an expositor of philosophical ideas. Let me first turn to what he says about the principle of trustworthiness. Except for a very minor point, I find that I agree rather than disagree with his argument to the conclusion that it is broad concurrence among acceptances, including the acceptance of my own trustworthiness, that provides the most illuminating explanation of my reasonableness of accepting my trustworthiness. The more direct application of the principle of trustworthiness to explain the reasonableness of accepting itself may be less important than my exposition suggests. If, however, I have placed excessive emphasis on the application of the principle of trustworthiness to itself, I did have a pair of reasons of doing so. The first, mentioned elsewhere, is that I consider it a condition of adequacy for a theory of reasonable acceptance that it apply to the reasonable acceptance of itself as well as other things. So, I do think that it is important that the principle of trustworthiness, if it accounts in any way for the reasonableness of accepting other things, also applies to the reasonableness of the acceptance of itself. I am inclined to agree that the application of the principle of trustworthiness to itself only succeeds in being explanatory in an illuminating way in the context of the larger acceptance system, however. The second reason that I have placed emphasis on the direct argument may be of greater importance. It involves a distinction between the acceptance of the principle of trustworthiness and the truth of the principle. The mere acceptance of the principle of trustworthiness does not explain why it is reasonable to accept that principle, though it does contribute in a small way to such explanation, but the truth of the principle does have explanatory power. My accepting that I am trustworthy may not be adequate to explain my reasonableness in accepting what

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I do because I may be incorrect in accepting that I am trustworthy, that is, it may be false that I am trustworthy in what I accept. But suppose that it is true that I am trustworthy in this way. Then the trustworthiness argument will be sound. My very trustworthiness in what I accept will explain why I am reasonable in accepting what I do, including that I am trustworthy. Now Mattey might reply that this explanation depends on the explanation of why I am trustworthy, which involves broader concurrence with the background system, and with that I agree. My only disagreement with him is that I think that my general trustworthiness in what I accept does provide some general explanation of why I am trustworthy and, moreover, reasonable in accepting what I do in particular cases. That includes the case of my accepting that I am trustworthy, even if the explanation depends for what illumination it provides on the systematic explanation of why I am trustworthy in terms of other matters. In general, I think it is incorrect to argue that since Y cannot explain Z unless X explains Y that, therefore, Y cannot explain Z. So, suppose I agree that my trustworthiness in what I accept cannot explain my reasonableness in what I accept unless my trustworthiness in what I accept is explained by other matters, for example, the kind of concurrence Mattey describes. It does not follow that my trustworthiness in what I accept cannot explain my reasonableness in what I accept. With that said, however, I agree with Mattey that the more illuminating explanation of the reasonableness of what I accept, including the reasonableness of accepting the principle of trustworthiness itself, depends on the more systematic explanation in terms of other things that I accept. I even agree that the explanation in terms of the principle of trustworthiness would collapse without my acceptance of those other things. I am, in fact, indebted to him for insisting on the point, because I can see that my emphasis on the role of the principle of trustworthiness in the trustworthiness argument has misled others into thinking that the broad concurrence, as Mattey calls it, is less important than the direct argument. That is not my view. I think that the direct argument does have some explanatory power but only when my trustworthiness is explained by the other systematic features of acceptance. The keystone cannot stand alone, and it cannot explain alone either. Some of my remarks suggested otherwise, though not the metaphor, and I am glad to have the opportunity to clarify the matter. I would like to comment on the court case in which a person declares that he is trustworthy in defense of his testimony. If I argue in support of my testimony that I am trustworthy in what I testify, another might well require evidence of my trustworthiness if they lack such evidence. But in a small community where I am well known, my remark, "I am trustworthy in what I testify," might well explain why it is reasonable for others to trust my testimony. If they know I am trustworthy as I say, then it is reasonable for them to trust what I say until it is shown to be false, and my trustworthiness together with their acceptance of it explains why it is reasonable for them to accept it.

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I should also like to comment on what Mattey says about competence in pursuing one's epistemic goals being a necessary condition of trustworthiness. In the demon case, I would say that the person with intellectual integrity who follows methods and procedures worthy of her trust is trustworthy in what she accepts because she is as trustworthy as the circumstances allow. Now Mattey says that the person accepts that she is competent in the pursuit of her goals. I agree that she must accept this. But Mattey needs to claim that she actually is competent though almost totally unsuccessful in seeking to accept what is true and avoid accepting what is false. Mattey seems willing to embrace this consequence that a person can be competent to achieve some purpose even though they are almost totally unsuccessful in achieving that purpose because of bad luck. His idea of competence appears to be that a person who is competent to achieve some purpose requires the cooperation of circumstances to succeed. I do not object to this claim of Mattey's, and I surely do understand the notion of competence. It is very close, indeed, to the notion of trustworthiness, for I have insisted that general trustworthiness is a capacity, as Mattey notes, to be trustworthy in particular instances of acceptance. Ifwe go beyond my claim to Mattey's, we must go beyond saying that the demonically deceived person is worthy of her own trust in the way in which she seeks to obtain truth and avoid error, though she almost totally fails to succeed through not fault of her own. We must also say that the demonically deceived person is also competent to obtain truth and avoid error, though she almost totally fails to succeed because of the deception. The question is whether this notion of competence is implicitly evaluative. What does her competence amount to if she is almost totally unsuccessful in her continuing efforts to obtain truth and avoid error? Is it just that she proceeds in the right way, the way she should proceed, despite her failure? I suggest that the notion of competence is implicitly evaluative, that the competent way to proceed is just the way she ought to proceed, the way, that is, that is worthy of her trust, even if the circumstances lead to her to failure in spite of her proceeding as she should. These are small matters of disagreement, however, and our agreement extends broadly to the account of broad concurrence Mattey has advocated as being central to my theoretical and explanatory purposes.

3.13. Reply to Manning Manning has argued in detail and with careful attention to my text that my account is defective. I am impressed with his philosophical acumen. His arguments are challenging and perceptive, but admit of reply. Manning argues against my position in various ways, but there are three central issues, and I believe all his arguments depend on these. He claims that coherence theories in general, and mine in particular, fail to fulfill a condition of adequacy for a theory

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of epistemic justification, namely, that justification must be truth conducive. Let us call this claim, as I have, the truth connection objection. He also claims that all coherence theories treat justification as inference, some kind of argument, as the condition of coherence, and he objects that some justification does not rest on argument or inference. Let us call this the inference objection. The third objection is that my account of justification in terms of coherence is viciously circular, the circularity objection. I wish to discuss these three objections, for, other than small matters of detail, I think all his objections rest on these three. First of all, consider the inference objection I have agreed that the foundationalist is right in claiming that not all justification results from inference or argument. Noting that we have not argued for everything that is justified, I say in both editions, "We must, therefore, agree with the foundationalist that we are justified in accepting some things without argument. (40, 1990. 46, 2000)" Moreover, an examination of the details of my theory and consideration of the definitions of coherence, do not entail that the justification resulting from coherence with a background system rests on inference or reasoning from the background system. If that leads Manning to conclude that I am not a coherence theorist, that seems to me to be an attempt, on his part, to appropriate the use of the term "coherence" to apply to theories that he thinks he can refute. My kind of coherence theory, call it r-coherence, if you like, is one that defines coherence in terms of a relation of coherence between a background system and a target acceptance. It is a relational theory. Relations of reasoning or inference are one sort of relation, but the theory I put forward, as one can note from the definitions quoted by Manning, define coherence in terms of relations of comparative reasonableness on the basis of the background system. The reasonableness of a belief may, of course, result from inference or reasoning in some cases, but in other cases, it will result from other relations of support among components of the system. The characterization of my account of coherence in terms of inference would be incorrect in many cases. Moreover, the intuitive idea behind a coherence theory is one of coherence as a matter of how things fit together or support each other, and the relations of fit and support need not be analyzed in terms of inference. I have insisted on this because, to be fair to Manning, I said things in both editions of the textbook that probably misled Manning. In order to illustrate how a target acceptance cohered with a background system, I used examples of defending the claim by reasoning in terms of the background system as a heuristic device to illustrate coherence. I presented the coherence theory of justification in the first pages and then introduced a game one might play with a critic. I said, "The game is a heuristic device for understanding the considerations that make a person justified in accepting something rather than a psychological model of mental processes." My intention was to illustrate how a background system coheres with a target acceptance using reasoning in a game as a heuristic device rather than defining coherence in terms of reasoning. If Manning was misled by my text, I must

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assume some of the blame, but my definitions of coherence are not open to the objection that coherence, on my theory, is defined in terms of inference, though inference may yield coherence and justification in some cases. So I can embrace the advantages of the foundation theory to the extent that I share the claim with the foundationalist that some beliefs are noninferentially justified. I disagree with the foundationalist who claims that such justification is independent of other things that the person accepts. I contend that the justification depends on coherence with other things the person accepts. I assume that is a disagreement of philosophical substance. Now let us tum to the truth connection objection. Here I can be brief. There are two sides or aspects to justification that I have separated in my theory ofjustification, the personal aspect and the undefeated or, as I now prefer to say, the irrefutable aspect. These two aspect are, in fact, combined in undefeated or irrefutable justification, for undefeated or irrefutable justification is personal justification that does not rest on errors in the background system which yields that justification. It is, however, irrefutable justification that is the condition that converts acceptance of truth to knowledge. If one chooses, as Plantinga does, to call the conversion condition warrant, then my view is that warrant is irrefutable justification. So what is the connection with truth? The basic idea is that there is a subjective aspect and an objective aspect to the truth connection in irrefutable justification. The subjective aspect is that I aim at accepting things just in case they are true. Moreover, I accept that I proceed in a trustworthy way that reliably leads me to truth. That is what I accept and is the connection with truth on the subjective side. The objective side is that my acceptance of this must be true, that is, it must be true that I proceed in a trustworthy way that reliably leads me to truth. For, if that is untrue, then the personal justification I have will be defeated or refuted by errors, untruths, in my background system. Manning says that truth conduciveness must come into justification and notes that I agree. My explanation of how truth connection comes in is, therefore, twofold. On the subjective side, the subject of knowledge accepts that there is a truth connection to yield personal justification, and, on the objective side, the subject must be right in accepting the truth connection to have an undefeated or irrefutable justification which converts to knowledge. If Manning demands more of a truth connection than that, I must leave him to satisfy his own demands, for I think there is no more satisfaction to be had. On the matter of circularity, notice, first of all, that there is no circularity in the definitions I give ofpersonaljustification and irrefutable justification. The analysis is not circular. I have claimed, however, that the principle of trustworthiness in what I accept has the merit of explaining why I am trustworthy in accepting what I do. Therefore, when I accept that I am trustworthy in accepting what I do, this principle of trustworthiness explains why I am trustworthy in accepting it as well as the other things I accept. So, what is his objection? As far as I can see, it is that he disallows circular explanation. Well,

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that is his fiat, but why should I allow that to settle the matter? We need an argument. Here is one that I gave and give that has special relevance to justification. Suppose you are seeking a complete theory to explain why a person is justified in accepting everything that they are justified in accepting. Assuming the theory is finite and a person is justified in accepting it, then the theory must explain why the person is justified in accepting it. Now, as to the question of whether using a theory of justification to explain why you are justified in accepting the theory is vicious, I do not see why I should find it vicious if I am only seeking to explain the matter to myself. For I consider myselfjustified in accepting the theory. Why shouldn't I use the theory to explain to myself why I am justified in accepting it? I use it to explain why I am justified in accepting everything else I consider myself justified in accepting Manning objects to this appeal to my trustworthiness because he objects to the inference from

1.

I accept that p in the interests of accepting that p if and only if p is true

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p.

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The argument is not a valid deductive one. Moreover, he may object even if! add the premises 3. I accept that I am trustworthy in what I accept and even, 4. I accept that my trustworthiness is successfully (reliably) connected with truth. that the argument from all the premises above to the conclusion that p is still not a valid deductive one, and he would be right. However, when I reflect on the matter for my purposes, when I reason to see where I am led from what I accept, then, I may appeal to what I accept in my reasoning. For what I accept represents my best efforts to obtain truth and avoid error. My reasoning from what I accept has all the hazards of nondeductive reasoning, but those risks are a good gamble if I am circumspect. It is, of course, a defeasible kind of reasoning, and there are times when the inference is defeated by further considerations, but that is the character of defeasible reasoning. The matter is of general interest, so let me elaborate further. Manning objects in detail to deriving any conclusions about the truth of any claim from the

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acceptance of it. The conclusion of p from anyone's acceptance of p is rarely deductively valid, though it is often cogent. Here is the difficulty that I think is the heart of the matter. One needs some premises other than acceptance ofp to obtain the conclusion that p. There are objections against drawing the conclusion, such as that the person has not accepted that p in a trustworthy way and, more skeptically, that even accepting something in a trustworthy way is not successfully truth connected. Now these objections might be met by the person who accepts that she has accepted that p in a trustworthy way that is successfully truth connected. But, and here is Manning's point, the most the person is entitled to is the premise that he accepts these things about trustworthiness and successful truth connectedness, while what is required is the content of these acceptance, or what the person accepts, namely, trustworthiness and truth connectedness. So, his point is that as long as we continue to simply add premises of the form-I accept that ... -to the argument, we shall never reach any conclusion about the thing accepted. So what should I say to that argument? First of all, I have amended my account in some published articles and in the second edition of the theory of knowledge so that the evaluation system of a person, the background system with which a target acceptance must cohere to be justified, includes reasonings from premises to conclusions. The first answer, therefore, is that ifthere is a reasoning from the premise that a person accepts various things to the conclusion that p, where p is one of the things that the person accepts, then the problem of deriving the conclusion is solved by the component of the evaluation system containing the reasoning. The second step is to note that such reasoning, though defeasible, is often justified. Suppose a person I meet at a philosophy conference accepts that he is Manning, for example. Should I conclude from the fact that he affirms and accepts that he is Manning that he is Manning? There is no rule of valid deduction to support the reasoning, but if! accept that he is trustworthy and that he is successfully truth connected in the matter, I will reason to the conclusion that he is Manning. Almost the whole of what we learn from the testimony of others is based on such reasoning, from what they accept and what we accept about them to the conclusion that what they accept is reasonable, justified, or, finally, true. But if we reason from what others accept and what we accept about their trustworthiness and reliability to the conclusion that what they accept is true, why should we not reason in a similar way in our case? There is a danger, of course, for every person is likely to be partial to his or her own views, but the remedy of refusing to reason from what we accept to the truth of anything to inoculate ourselves against impartiality is worse than the threat of the malady. We reason as Manning says we should not, and I take leave to disagree with my distinguished critic and affirm that we should. Reason confronts an existential choice. Either I place my trust in what I accept and proceed to conclude what I can about the matters that interest me

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from it, or I refuse to venture beyond the premises affirming that I accept various things and limit my conclusions about the world to egocentric observation about my own acceptances. I hope he will excuse me if I venture forth to the conclusions beyond my acceptances. Whatever he says in his philosophy, I am sure that in practice he does the same. I have said more about circularity in reply to others as it arises concerning trustworthiness. In conclusion, however, I wish to reiterate that my definitions of knowledge and justification are not themselves circular. I could retain those definitions and give up the principle of trustworthiness and the use of that principle to explain why a person is justified in accepting it. I defend the principle of trustworthiness and the application of that principle to itself because it seems to me to be true and the application of it explanatory. It is not necessary to my analysis of knowledge.

3.14. Reply to Rott Rott has developed a very valuable theory of the dynamics of belief which he has sought to connect with the synchronic theory of knowledge that I have constructed. I read his paper after replying to some of the others because of difficulty opening his file, and some of his objections and my replies are contained in other replies to which I refer the reader to avoid some duplication. He has clearly found my 1990 theory of knowledge useful to his own purposes, and he is welcome to work with the earlier account of knowledge and to amend it for his own purposes. It may, after all, turn out that the earlier work will have an importance that I did not perceive and a useful application that I did not intend. I would welcome that. However, I did not, in fact, intend the use of the members of the ultrasystem in the 1990 and earlier accounts to be viewed dynamically, I regarded each member of that system, which corrected errors in the acceptance system in different ways, to provide tests at a time for whether the justification a person has at a time depends on his accepting things that are false. There is nothing dynamic in that account, though, again, Rott is welcome to reinterpret what I have said in any way that he finds useful. I shall not, however, comment on Rott's discussion of the 1990 account ofthe ultrasystem, for I think that Haas has shown that it is defective formally and Rosenthal has a good counterexample to it. I refer the reader to those articles and my replies. Now Rott raises the objection that in my earlier account, 1990, I did not say enough about what is involved in it being more reasonable for a person to accept one thing than another, and especially, on some assumption the person makes. I hoped to offer some illumination in 2000 by introducing the notion of preferences over acceptances, that is, preferring accepting one thing to another, as a component in the evaluation system. I then added the argument, made more

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explicit in Self-Trust, if a person is trustworthy in what they prefer for the purposes of pursuing the truth objectives, then they are reasonable in what they prefer for those objectives. Finally, if a person is reasonable in her preference for accepting one thing to another, then it is more reasonable for her to accept the one thing than another. I took preferences of this sort, contained in the evaluation system, to be essential to dealing with objections, previously called "competitors," to a target acceptance. Rott alleges that my current account, 2000, does not deal with the original Gettier example. I have explained in reply to Olsson how my reply goes with respect to another example. With respect to the example of Smith, who is justified in believing that either Jones owns a Ford or Brown is in Barcelona, when he has strong evidence that Jones owns a Ford, my solution is based on the assumption that the claim that Jones does not own a Ford is an objection (competitor) to what Smith is justified in accepting, namely, that Jones owns a Ford or Brown is in Barcelona. So Smith must be able to answer that objection on the basis of his background system, that is, it must be more reasonable for Smith to accept that Jones owns a Ford than to accept that he does not own a Ford. Now Smith need not accept Jones owns a Ford for this to be true, but he must prefer accepting that Jones owns a Ford to accepting that he does not, and that preference, contained in the original evaluation system of acceptances will not be a t-state in the ultrasystem. The reason is that it is a preference for accepting something false over something true. As a result, it will not be more reasonable for Smith to accept that Jones owns a Ford than that he does not on the ultrasystem, and Smith will not be able to meet the objection that Jones does not own a Ford on that system. Hence, he will not have an undefeated justification for accepting that Jones owns a Ford or Brown is in Barcelona. That explains why he does not know on the new account. The Grabit case is more interesting. Rott asks about the relation to the newspaper case and to the question of unavailable misleading evidence. Now the simple difference between the examples is as follows. A person, like me, who knows Tom Grabit when he sees him, does not need to have any views about what Tom Grabit's father is saying about his whereabouts to know where Tom Grabit is when he sees Tom Grabit clearly before him. The objection that Tom's father is somewhere saying that Tom is elsewhere can be neutralized by my accepting that I see Tom before me and know him when I see him. That is all true and retained in my ultrasystem. By contrast, the person trusting the newspaper for information does need to accept that the newspaper is trustworthy in how it treats the story she reads, which it is not because it will retract the story on political grounds, and hence her justification is defeated because she cannot meet the objection that the newspaper is not trustworthy in how it treats the story. Sometimes unavailable misleading evidence makes a difference and sometimes it does not. Whether it does or not depends on diverse factors but often on whether the misleading evidence must be accepted not to exist for the evidence

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one has to be justificatory. The evidence of my senses does not depend on my accepting that Tom's father did not say he was elsewhere, but the newspaper reader's evidence does depend on her accepting that the newspaper's treatment of the story is trustworthy. Now let me come to a more fundamental issue that is closer to Rott's interests, namely, the relevance of the dynamics of belief to rationality and knowledge. I have offered some reflections elsewhere which I shall repeat briefly here, though it falls short of a theory. The basic idea is that for a person to be trustworthy in what they accept, rational in what they accept, at a time, they must be trustworthy in how they change what they accept. But that is not enough, for they must be trustworthy in how they change the way they make changes, for example, in the methods they use. Now it is concerning method that Rott and 1 probably disagree. Rott favors conditions of consistency and closure. I have discussed these in reply to Spohn, and refer the reader to those replies. Basically, my argument is that natural acceptance systems are usually going to be inconsistent, and that such inconsistent systems, provided they are not deductively closed, may enable us to carryon the business of justification, of meeting objections to what we accept, in a rational manner. Every logician who thinks about hard problems will make some mistakes, reasonably accept that some set of abstract logical claims is consistent when it is not, but that does not interfere with the justification of what he accepts about most things, about his family, for example. Moreover, deductive closure, however interesting in formal logic, is not a policy any person should rationally follow in acceptance. It makes it too difficult to survey what you accept, and, since we are usually inconsistent in what we accept, it renders what we accept useless for the purposes of rationality and justification. However, I agree that consistency is a reasonable goal of acceptance, a desideratum. It is just that the achievement of it is not a necessary condition of reasonable acceptance or justification of a claim resulting from coherence with it. Closure, by contrast, strikes me as extraordinarily uneconomical as a cognitive constraint of a natural subject even, if we could achieve it. So, I agree with Rott that knowledge and belief revision, or, as 1 prefer, trustworthy change in what one accepts, is a condition of synchronic trustworthiness and knowledge synchronically considered. Concerning method, however, we have to change our methods in a trustworthy manner. Contrary to Rott, I do not see much promise of imposing holistic constraints on the coherence of a system, though we need to adopt, tentatively and subject to change, methods for change. For me, coherence is a relationship of a target claim to a background system rather than a holistic feature of the system, though some holistic features may be required for the relationship. There is a basic difference between us, I suspect, concerning acceptance and methods of acceptance. I do not give a priority to method. We change what we accept, including the methods for acceptance and changing what we accept, in a trustworthy manner without

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giving priority to one over the other. What we accept rationally influences what methods we accept just as what methods we accept influences what we accept. Neither comes before the other. They are tied together in a loop of our trustworthiness.

3.15. Reply to Haas Haas has carefully analyzed some implications of slightly differing views that I gave as I attempted to refine an account of undefeated justification by considering arbitrary replacements of accepting what is false with accepting what is true. I tried to impose various logical constraints, which differ in their implications, as Haas notes. In one instance, the change was inadvertent, but others were motivated. However, what Haas says and has proven is correct. Moreover, discussions with Haas, invaluable ones, led me to seriously rethink my position on the ultrasystem and undefeated justification. His work is exceptional, and as I look upon it with admiration, I can only cheer for the excellence of the refutation of my past views. I have changed my analysis, and I am glad to learn that Haas is not yet ready to offer a refutation of the new one! That may be as good a confirmation as I can get that there is something to the present account. I have discussed my present account in reply to other critics in this volume, especially Rosenthal and Klein.

3.16. Reply to Rosenthal Rosenthal has raised an objection to my treatment of the Gettier problem in the first edition of Theory of Knowledge showing that the analysis is too restrictive. Basically, I required that the justification a person has could withstand any arbitrary replacement, except for a logical constraint, of the acceptance of a false statement with the acceptance of its denial. Rosenthal has shown quite clearly why that analysis is defective, namely, that a person might be justified in accepting that p, accept that ifp, then q (where this is a contingent conditional) and accept that q. Suppose that the justification that S has for p does not depend on his acceptance that if p, then q or his acceptance of q, and that both of these are false. If only the latter is replaced, that is, if the acceptance of q is replaced by the acceptance of not-q and the acceptance of if p, then q is not replaced, then S would, as a result, no longer be justified in accepting that p. But, since the justification for p does not depend on the acceptance of if p, then q and the acceptance of q, the justification S has for p should, contrary to the analysis, suffice for knowledge. So the analysis is too restrictive.

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Undefeated justification must be based, I now argue, on an ultrasystem containing all states of acceptance wherein what is accepted is true, marked as t-acceptances, states of preference over acceptance in which the acceptance of something false is not preferred to the acceptance of something true, marked as t-preferences, and states of reasoning that are sound with true premises and true conclusion, also marked as t-reasonings, that is, truth states, as well as other states, of the original system left unmarked. The use of the system to achieve undefeated justification requires that the original, unmarked states be acknowledged, but only that the content ofthe t-states be used for justification, that is, to meet objections to the target acceptance. A justification for S is undefeated or irrefutable by errors of the subject if and only if S is justified in accepting that p on the ultrasystem in this way. This amendment deals with the objection raised by Rosenthal because, though it requires justification on an acceptance system in which the content of all states of accepting something false are disallowed in justification, it does not require justification be sustained in a system in which false states of acceptance may be arbitrarily replaced with acceptances of their denials. Hence, in the example above, the analysis would require the subject be justified on the basis of an acceptance in which both the content of the acceptance of if p, then q and the acceptance of q were disallowed because both if p, then q as well as q itself are false. Rosenthal suggests that this sort of suggestion fails because of the example suggested by Russell of the man looking at a clock which, though he is ignorant of the fact, has stopped at ten minutes past three o'clock, perhaps the day before, when it is now ten minutes past three o'clock. According to Rosenthal, the man need not accept anything false, for example, that the clock is now running, to be justified in accepting that it is ten minutes past three o'clock now from reading the clock. He says the person might reason, This is a clock. It shows ten minutes past three. Most clocks work properly most of the time and therefore show the right time most of the time. So I conclude that this clock shows the right time right now and believe that it is ten minutes past three. My answer to this is that I have a more rigorous requirement for justification than Rosenthal imposes, and the example does not meet the requirement. The requirement is that the evaluation system of the person, the system containing what the person accepts, the person's preferences over acceptances, and, finally, the reasonings of the person concerning acceptance, must enable the person to meet objections to what he accepts. It is clearly one objection to what the person accepts that the clock is not running. So the person should be able to answer that objection. I do not require that the person actually accept that the clock is running, but the person must prefer accepting that the

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clock is running to accepting that the clock is not running or the person is not justified. It is that preference that makes it more reasonable for the person to accept that it is more reasonable for him to accept that the clock is running than to accept that the clock is not running. But that preference, the preference to accept that the clock is running over accepting that it is not running is not a tpreference, because it involves preferring to accept something false, that the clock is running, over something true, that it is not running. Therefore, this preference, a crucial one for meeting the objection that the clock is not running, will not be contained as a t-state in the ultrasystem, and the objection that the clock is not running cannot be met on that system. So the justification would be defeated. Now Rosenthal might wonder why, if the reasoning he suggests above remains in the ultrasystem, that would not suffice for justification? My answer is that it might suffice for some kind of justification, it does supply some inductive confirmation for the conclusion, but more than that is required for the kind ofjustification that converts to knowledge. It does not suffice that one have some reasoning to support the target acceptance. One must also be in a position to meet objections to one's reasoning on the basis of one's ultrasystem. One objection to the reasoning is that the clock is not running, and that cannot be answered on the basis of the ultrasystem. It is important to notice, moreover, that states of acceptance, preference over acceptance and reasoning with acceptance need not be something that is occurring or has occurred to the subject. They are functional states that provide a capacity to respond to objections which, having not been raised, have not elicited response. But the system must provide the materials, it must have the right evaluative stuff, to answer objections. That is missing in the example from Russell as Rosenthal presents it. Moreover, a similar point, which I have made elsewhere, arises with respect to the Chisholm example of the man who takes a Terrier to be a sheep. One objection to what he accepts, namely, that there is a sheep in the meadow, is that what he takes to be a sheep is not a sheep. To meet the objection, the person must prefer accepting that what he takes to be sheep is a sheep over accepting that what he takes to be a sheep is not a sheep, and that preference is not a t-state because it involves preferring accepting something false over accepting something true. Again, the absence of the t-preference in the ultrasystem will lead to the defeat of the justification on that system. Finally, what should we say about the proposal that Rosenthal makes? It is a very good one. The idea is that one of the original justifications a person has must remain when the acceptance of what is false is systematically replaced with acceptance of what is true. One problem, which led me to require that t-states and unmarked states both remain in the ultrasystem, is the problem of knowing that you accept things, when, unknown to you, what you accept is false. This problem is raised by Klein and answered by Truncellito in this volume. Suppose that a person seeing the clock in Russell's example accepts that the clock is

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running. He would not know that the clock is running, but he would know he accepts that the clock is running. Yet Rosenthal would require that the man be justified in accepting that he accepts that the clock is running relative to a system in which acceptances of falsehoods are replaced with acceptances of truths, and, therefore, in which he accepts that the clock is not running. How can the person know that he accepts that the clock is running relative to a system in which he accepts that the clock is not running? Rosenthal might well have an answer to this, but I do not see what it is. Such problems have led me to abandon the requirement of replacing false acceptances with true acceptances and to turn to an improvement on accounts in which the acceptance of falsehoods are eliminated.

3.17. Reply to Bender Bender, whose philosophical talents I have long admired and enjoyed, has written a studied critique based on careful reading of the texts. So it is a special challenge to try to deal with it. I think that some misunderstanding persists, and that is, no doubt, my fault. At any rate, his citation of what I have said provides anyone with a clear basis for deciding whether my reply is already contained in what I had written previously or contains some novelty. My basic claim is that internal coherence yields knowledge when combined with systematic truth that shields the coherence from refutation based solely on errors contained within the background system. I argued, as Bender accurately notes, that the subject must accept that she is trustworthy in what she accepts and, moreover, that this trustworthiness is truth connected in a reliable manner. Furthermore, I have contended that the person must, in the case of a particular target acceptance that p, be right because of the trustworthy way in which she accepted it. Bender focuses on an argument from the general trustworthiness of acceptance to the trustworthiness of a particular acceptance that p and, further, to the reasonableness of accepting that p. Now Bender objects that the argument begs the question against a serious philosophical skeptic. But I agree with his claim and have said so. As an argument against a serious philosophical skeptic, it is a petitio to argue for the reasonableness of accepting that one is trustworthy in what one accepts by appealing to the premise that one is trustworthy in what one accepts. That is why I have insisted, contrary to such an admirable defender of common sense as Moore, that one cannot prove that the skeptic is wrong. Bender says that I have not established the claims needed to prove that the philosophical skeptic is wrong. I completely agree with him, for I see no difference between proving that skeptic is wrong and establishing what would be required to prove that the skeptic is wrong. That is not what I was trying to do in my later work, and I agree it cannot be done.

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However, I now deny that I must be able to prove that the skeptic is wrong, when he denies that I know that p, in order for me to know that p. Though I cannot prove that the skeptic is wrong, I can know that the skeptic is wrong, and, indeed, I can know that I know this. Bender also wishes to deny this. His argument seems to rest on agreement that the principle of trustworthiness of acceptance is needed for the evaluation system, containing what a person accepts, but on his denial that a person can be justified in accepting that he is trustworthy by the reasons that he has for accepting that he is trustworthy. He puts this by saying that a person is not epistemically justified, by which I think he means, I am not certain of this, justified in a way that would satisfy a skeptic with opposing views, that is, satisfy the skeptic by showing the skeptic that he was wrong. But again, I agree that a person is not justified in this sense, for I agree that we cannot prove the skeptic wrong without begging the question. So, there just is no issue about this between us. What, then, is the issue? In part, I think there is a verbal problem which I created by an unfortunate use of the word "skeptic" in the first edition of Theory of Knowledge which I corrected in the second edition, namely, the use of the word "skeptic" in the justification games that I used as a heuristic to assist a student reader to understand personal justification and ultrajustification. I rectified this by speaking of a critic rather than a skeptic in the second edition. I did not intend that the critic be regarded as a philosophical skeptic. I can examine my views critically without taking on the heavy mantel of a philosophical skeptic. To be justified, my views must pass the test of my own critical examination of them. They need not pass the test of Descartes exercising hyperbolic doubt, however. But verbal misunderstandings aside, there is an issue of fundamental importance between us. I think of justified acceptance, personally justified acceptance, in my technical expression, as acceptance that has the capacity to answer the objections to it in terms of the background system of the subject. Suppose I consider whether I am justified in accepting something. What will I do? I will consider other things that I accept, my preferences concerning acceptances and my reasonings in the matter. What else can I do? Now, as I consider critically my acceptance, I consider objections, those I might imagine raised by in internal critic, and how I can reply in terms of what I accept, prefer to accept and my reasonings about the matter. Again, what else should I do? If I cannot appeal to what I accept, for example, I am immediately rendered mute, and my attempt to proceed critically ended before it begins. Now, I agree that in proceeding in this way, I am accepting that I am worthy of my trust in what I accept, in my preferences over acceptances and my reasonings concerning acceptance. One question I might critically raise is what reasoning I might use to defend my acceptance of my trustworthiness. There are two answers. One is my success in obtaining truth and avoiding error in what I accept. This is induction from other cases. The other answer is one that arises when I consider why I need

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to accept the general principle of trustworthiness when I appeal to what I accept to meet critical objections. I need it to explain why I am reasonable to accept what I do. What explains my reasonableness in what I accept is my trustworthiness in what I accept. However, if this argument has merit, I note that it applies to itself. What explains why I am reasonable to accept that I am trustworthy is my very trustworthiness in what I accept. Now Bender dislikes this argument because it is circular. My reply is that any theory of justification that is complete must apply to itself and, thus, be circular. Thus, I contend that application of a theory of justification to itself is required, and, therefore, not a defect. The argument is simple. Suppose someone alleges that a theory of justification is complete in the sense that it explains why a person is justified in accepting anything that she is justified in accepting. Now suppose that the question arises as to whether the person is justified in accepting the theory of justification itself. If the theory is complete, it must answer this question. It must apply to itself as well as to other things. The deep truth, as I see it, is that a fundamental principle of justification, like the principle of trustworthiness, is and ought to be a principle that applies to itself. That is why this circularity is virtuous, though not as an argument against a genuine philosophical skeptic. Aside from circularity, Bender argues, as I have, that personal justification is not enough for knowledge, and that something more is required. I agree. What is required, as I have contended, is the truth of what one must accept to obtain personal justification. Now here we reach the basic premise of contention. Truth is not enough, he says, no matter how much of what one accepts is true. Here, I humbly disagree. Bender construes my argument as one saying that if! am trustworthy in what I accept, and if! am not deceived in ways that skeptics have imagined I might be, then I know. But that is not my argument. I am trustworthy in what I accept and not deceived in ways that skeptics have imagined, and that is part of why I do know, but not all. I must be able to answer other objections, not only the objection that I am not trustworthy in accepting that p, in order to be personally justified. Bender objects that the truth cannot be enough. What I accept to defend my views cannot depend on their truth for them to be reasons adequate to the task of defense. But why does he think that? He presents an argument with a line affirming that a person is trustworthy in his Biblical acceptances, having inferred this from his general trustworthiness in acceptances. Bender obviously considers the person not to be trustworthy in his Biblical acceptance and intends the argument as a reductio of my trustworthiness argument leading to conclusions about the reasonableness of what the person accepts. The argument refutes his observation, however, that the truth of a premise cannot decide whether it is a reason for accepting the conclusion. For Bender assumes that the line that the Biblical acceptances are trustworthy is not true, and that is why he rejects it as a reason for concluding that such acceptances are reasonable.

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The person may use the premise that the Biblical acceptances are trustworthy as one of his reasons, to be sure, but it is not a reason for accepting the conclusion because it is false. In one crucially important sense of "reason" the person has failed to provide a reason for accepting his conclusion. For one defect of a premise that undermines its claim to be a reason for accepting a conclusion is simply the falsity of premise. We must be careful here not to get entangled in verbal disputes over the word "reason," for it is an ambiguous notion, but an unsound argument does not establish the conclusion, and false premises make an argument unsound. Bender knows that. Truth matters. I allege that it matters enough to convert personal justification into knowledge. The truth of the premise that one is trustworthy in what one accepts and that trustworthiness is successfully truth connected can make the difference that converts internal coherence into knowledge. I do not claim to have refuted Bender's claim that this does not prove the skeptic wrong. I do claim to have refuted Bender's claim that my account of the conditions of knowledge is insufficient for knowledge if it does not prove the skeptic wrong. Coherence plus truth, especially concerning trustworthiness and reliability, though not only concerning that, explain why we know. Finally, I do think that Bender has put forth a position and defended it admirably concerning the relationship between genuine skeptical objections and knowledge. We might call it the impartiality condition, namely, that the reply to any objection sufficient to defend a claim to knowledge must be impartially effective. It is a sufficient reply to one person only if it is a sufficient reply to another. This is a most plausible claim, but one I reject. Whether a reply to an objection is sufficient for a person depends on what that person accepts. What one person accepts, another does not. So my reply to an objection might be sufficient for one person but not another. More specifically, my reply to an objection I consider may be sufficient for me because of what I accept though not sufficient for the genuine philosophical skeptic.

3.18. Reply to Klein Klein has raised a number of interesting issues and questions about the theory of knowledge I have articulated. He also has some kind things to say about me as a philosopher which I appreciate. I first met Klein a very long time ago when we were both very young philosophers, and, as he notes, we have carried on a dialogue over a long period. His contributions have been insightful, penetrating and have led me to modify my theory of knowledge. I am much indebted to him for the application of his formidable talents to my work of such a long time. There are some points he raises where the interpretative take on what I said makes me uncomfortable, but if someone who has been as attentive

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to what I have written as Klein is misled in some way, there must be some fault in what I said, and it is useful to attempt to correct that. Here are my replies. First of all, consider the problem about knowing that one accepts something one does, in fact, accept, that p, when, as it turns out, p is false. The reply I would offer and endorse is the one that Truncellito supplies. The uitrasystem does not replace my acceptance system but is, instead, a theoretical construct used to test whether justification depends on error and is, consequently, defeated by the error. As Truncellito notes, I do, in fact, accept that p, that acceptance is part of my acceptance system, so when I accept that I accept that p, what I accept is true, not false. The problem Klein raises is an interesting one, and it has led me to make explicit that justification based on the uitrasystem must acknowledge the acceptances in the original acceptance system, for it is true that I accept those things. The restriction placed on acceptances used in the ultrasystem to meet objections, that is, for coherence with the system, is that the content falsely accepted, the content that p, when p is false, cannot be used to meet objections. But my acceptance that p, though not the content, p, itself, can be used, for it is true, not false, that I accept that p. Now for the case ofD. Pendable. First of all, as I note elsewhere, I do not assume that acceptance systems are deductively closed. That would be unrealistic. No one deduces all the deductive consequences of what they accept. Nevertheless, it would be a small modification of the example to suppose that someone deduced from the claim that D. Pendable will be at the meeting that he will not die of a heart attack before the meeting. Now is this a problem for my theory? It is not. I think that people would divide in their intuitions about what they know about the future, especially in such cases. Some would think that, though there is no reason to think the man will die of a heart attack, there is an objection to the claim that he will not, namely, that people do die of heart attacks even when there is no reason to expect that they will. Now, I would say that such an objection to the claim that the person will not die of a heart attack before the meeting is also an objection to the claim that the person will attend the meeting. Dead men do not attend the AP A. So, do we know that D. Pendable will not die of a heart attack and will attend the AP A meeting, or should we allow that the objection that people do die of heart attacks, even when there is no reason to expect that they will, cannot be met and, therefore, that we lack knowledge? I think that the answer depends on the success of neutralization for the subject. Some will be inclined to reply to the objection-people do die of heart attacks when there is no reason to expect they will-that D. Pendable will not have a heart attack before the meeting and think it just as reasonable to accept that in conjunction with the objection as to accept the objection alone. They will consider the objection neutralized and affirm that they know. Others will say there is no way of telling about whether D. Pendable will have a heart attack, and so they will say it is more reasonable to accept the objection then to accept the conjunction of it with the disclaimer that D. Pendable will not have a heart

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attack. All I will say in defense of my account is that it explains in the right way differing intuitions in terms of what a person thinks about what is reasonable and how reasonable it is to accept that D. Pendable will not have a heart attack before the meeting. That seems a merit of the account. Now for the objection that my account cannot deal with the closed box example. Klein assumes, though I would not, that if a person accepts something, then, if what they accept is true, they can justify anything that follows from it. I would say that what matters is whether they can meet objections to the claim in terms of their evaluation system. One objection that is relevant in this case is that the person does not have any reason for accepting that there is a triangle in the box. The person can only meet that objection by replying that Sally told him there is, but, in fact, she did not, and that justification would be defeated. It is not adequate for the purposes of justification that the person accept that there is a triangle in the box and be right about that when he lacks a justification that is undefeated. Now Klein thinks I cannot make this reply because there are cases, those of distinct memory, I suppose, when a person knows something even though they have forgotten the evidence. But I would say that even in such cases acceptance is not sufficient. In addition, the person must evaluate the memory as being based on correct information, even if the person no longer remembers the source of it. Again, that is required for the purposes of justification, for it is an objection to any memory belief that it is not based on correct information. Now if the memory is based on correct information, the justification will be sustained in the ultrasystem, otherwise it will be defeated. Finally, concerning skepticism, I do hold, contrary to what Klein alleges, that my evaluation system must contain the capacity to meet all objections, but that might in some case rest primarily on my preferring to accept what I do, that I perceive a zebra, rather than accepting that I am deceived, or any other objection contradicting what I accept. I agree with much of what Klein says about skepticism. Some of his criticism of my views on skepticism are due to a misunderstanding I caused by an ambiguous use of the word "skeptic" in the first edition of Theory of Knowledge. I used the term to represent a kind of internal critic raising objections, as well as to represent a serious external skeptic. In the second edition, I changed the expression used to characterize the internal critic to "critic" hoping to avoid the misunderstanding. My view about the external skeptic is that we can know, and know that we know that he is mistaken, but that we must appeal to what we accept as a source of reasons to argue against him. I assumed that the external skeptic would note that I must accept that I am worthy of my own trust in what I accept to argue against him. If the skeptic denies this, I may, as Klein suggests, ask him for his reasons. Suppose he has none but asks if we have any for thinking the opposite. Ifwe have none, and he has none for his opposing position, then, it seems to me, we should concede that the issue is a draw. If we attempt to argue against him,

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appealing to what we accept, it seems to me that he is entitled to claim that the trustworthiness of what we accept is at issue, and appeal to what we accept is not legitimate. Finally, Klein asks if we need to answer the external skeptic. My answer is that we do not need to answer the external skeptic to know that the skeptic is in error and to know that we know this. We do need to accept that we are trustworthy in what we accept, even if we do not need to prove it to the external skeptic, to obtain the sort of justification that requires that we answer our own objections to what we accept. We do need to have the capacity to answer our own objections, those that arise from what we ourselves accept, to obtain justification which, when undefeated or irrefutable by errors of own, converts to knowledge.

3.19. Reply to Truncellito It is good to have the volume end with such a perspicuous defense of my account by so fine a philosopher as Truncellito against so formidable a critic as Shope. * There is little for me to say in reply, for I agree with what he said, and I admire the way has said it. Bravo!

ENDNOTES

* I would add that another article appeared in an undergraduate journal of philosophy, Stoa, Vol. 2, Issue 2, 2001, written by Jonathan Tweedale, entitled, "Epistemic Humility and Undefeated Justification," arguing in a similar way that my account did not fall victim to the problem about knowing that one accepts something when, unknown to one, what one accepts is false. He does not discuss Shope, but his defense, though that of an undergraduate, is professionally written.