Consciousness and Persons Unity and Identity
Michael Tye
Consciousness and Persons
Representation and Mind Hilary P...
29 downloads
850 Views
835KB Size
Report
This content was uploaded by our users and we assume good faith they have the permission to share this book. If you own the copyright to this book and it is wrongfully on our website, we offer a simple DMCA procedure to remove your content from our site. Start by pressing the button below!
Report copyright / DMCA form
Consciousness and Persons Unity and Identity
Michael Tye
Consciousness and Persons
Representation and Mind Hilary Putnam and Ned Block, editors Representation and Reality Hilary Putnam Explaining Behavior: Reasons in a World of Causes Fred Dretske The Metaphysics of Meaning Jerrold J. Katz A Theory of Content and Other Essays Jerry A. Fodor The Realistic Spirit: Wittgenstein, Philosophy, and the Mind Cora Diamond The Unity of the Self Stephen L. White The Imagery Debate Michael Tye A Study of Concepts Christopher Peacocke The Rediscovery of the Mind John R. Searle Past, Space, and Self John Campbell Mental Reality Galen Strawson Ten Problems of Consciousness: A Representational Theory of the Phenomenal Mind Michael Tye Representations, Targets, and Attitudes Robert Cummins Starmaking: Realism, Anti-Realism, and Irrealism Peter J. McCormick (ed.) A Logical Journey: From Gödel to Philosophy Hao Wang Brainchildren: Essays on Designing Minds Daniel C. Dennett Realistic Rationalism Jerrold J. Katz The Paradox of Self-Consciousness José Luis Bermúdez In Critical Condition: Polemical Essays on Cognitive Science and the Philosophy of Mind Jerry Fodor Mind in a Physical World: An Essay on the Mind-Body Problem and Mental Causation Jaegwon Kim Oratio Obliqua, Oratio Recta: An Essay on Metarepresentation François Recanati The Mind Doesn’t Work That Way Jerry Fodor Consciousness, Color, and Content Michael Tye New Essays on Semantic Externalism and Self-Knowledge Susana Nuccetelli Consciousness and Persons: Unity and Identity Michael Tye
Consciousness and Persons Unity and Identity
Michael Tye
A Bradford Book The MIT Press Cambridge, Massachusetts London, England
© 2003 Massachusetts Institute of Technology All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher. This book was set in Sabon by UG / GGS Information Services, Inc. and was printed and bound in the United States of America. Library of Congress Cataloging-in-Publication Data Tye, Michael. Consciousness and persons: unity and identity / Michael Tye. p. cm.—(Representation and mind) “A Bradford book.” Includes bibliographical references and index. ISBN 0-262-20147-X (hc.: alk. paper) 1. Consciousness. 2. Whole and parts (Philosophy). I. Title. II. Series. B808.9.T935 126—dc21
2003 2002040999
10 9 8 7 6 5 4 3 2 1
For Lauretta, Cecily, and Claudia
Contents
Preface
xi
Introduction: Kinds of Unity and Kinds of Consciousness 1 I.1 Preliminary Remarks 1 I.2 Cases of Consciousness (or Its Absence) I.3 Kinds of Consciousness 5 I.4 Kinds of Unity 11
2
1 The Unity of Perceptual Experience at a Time 17 1.1 Multiple Experiences and the Problem of Unity 17 1.2 Undermining the Problem as Standardly Conceived 21 1.3 The One Experience View 25 1.4 An Account of Synchronic Phenomenal Unity 36 2 The Body Image and the Unity of Bodily Experience 43 2.1 The Body Image 43 2.2 A Theory of Bodily Sensations 49 2.3 The Problem of Bodily Unity 62
viii
Contents
3 The Unity of Perceptual and Bodily Experiences, Occurrent Thoughts, and Moods 67 3.1 Opening Remarks 67 3.2 Perceptual Consciousness and Experience of the Body 68 3.3 Unity and Conscious Thoughts 78 3.4 Unity and Felt Moods 81 4 The Unity of Experience through Time 85 4.1 Examples of Unity through Time 85 4.2 The Specious Present and the Problem of Diachronic Unity 86 4.3 An Account of Unity through Time 95 4.4 Some Mistakes, Historical and Contemporary 102 4.5 Carnap and the Stream of Consciousness 106 5 Split Brains 109 5.1 Results of Splitting the Brain 109 5.2 Multiple Personality Disorder, Split Brains, and Unconscious Automata 113 5.3 Indeterminacy in the Number of Persons 117 5.4 Disunified Access Consciousness 121 5.5 Disunified Phenomenal Consciousness: Two Alternatives 126 5.6 The Nontransitivity of Phenomenal Unity 129 6 Persons and Personal Identity 133 6.1 The Ego Theory and the Bundle Theory Quickly Summarized 133 6.2 Objections to the Ego Theory 134 6.3 Objections to the Bundle Theory 138 6.4 A New Proposal 140 6.5 Problem Cases 143 6.6 Vagueness in Personal Identity 154
Contents
Appendix: Representationalism Notes 177 References 187 Index 195
165
ix
Preface
Some philosophers like to publish large, dense books. I do not. The simple fact is that large philosophy books are rarely read carefully. This is especially true if the books are hard going, as more often than not they are. Philosophers usually take great care in stating their positions; but, in my experience, they have less patience when they read others. I am no different in this regard. My attention span is limited. I don’t like having to work hard at trying to understand what the book or article I am reading is saying. I want clarity and, where possible, brevity. The present book is written for those who share my preferences. Its chapters are divided into numbered sections, typically only a paragraph or two long. The book is clear, I hope, both in structure and content. And it is relatively short. There are even a few cartoons and illustrations to provide some light relief. The issues the book addresses, however, are not light or easy. They have taxed some of the greatest philosophers of the past, and they are slippery and confusing. This is the third book I have written at least partly on consciousness and it may well be asked how many is enough. I concede that three seems excessive, especially given the
xii
Preface
veritable explosion of books on consciousness in the last ten years. But excess is not always a bad thing, even if we agree that Oscar Wilde and William Blake went a little over the top when they commented (respectively), “Nothing succeeds like excess” and “The road of excess leads to the palace of wisdom.” Still, it was an epiphany, rather than a qualified respect for excess, that led to the present work. The epiphany occurred a couple of years ago, as I was sitting in my garden, having a drink late in the afternoon. (The drink, as I recall, was not alcoholic, as some have supposed.) The air was heavy, there were sounds of birds calling to one another, bees buzzing around nearby flowers, the smell of damp grass, a profusion of colors. What struck me with great intensity was the unity in my experience, the way in which my experience presented all these things to me together. What also struck me was that remarkably this unity hadn’t really struck me before, that it was as if I had failed to notice it! Unity is a fundamental part of our experience, something that is crucial to its phenomenology. It is so fundamental, so much a part of our everyday consciousness, that it is easy to overlook. And this, I speculate, is why more has not been written about it in the recent vigorous debate about phenomenal consciousness. Be that as it may, unity is an important topic that connects both with empirical studies in psychology of people with split brains and with the theoretical, philosophical issue of personal identity. The book begins with an introduction to the topics of unity and consciousness. Different kinds of unity and consciousness are distinguished, largely to help avoid misunderstanding as to the scope of the theory that follows. Chapter 1 is concerned to undercut one standard way of thinking about unity for the case of perceptual experience at
Preface
xiii
a single time and to offer an alternative account. Chapter 2 extends this account to the case of bodily sensations at a single time; in the course of so doing, it provides a theory of these sensations. This theory is compatible with my past proposals on bodily sensations (e.g., in Tye 1995a) but it goes beyond them in important ways. Chapter 3 extends the account of unity still further to cover unity for perceptual experiences, bodily sensations, conscious thoughts, and felt moods, again at a single time. Chapter 4 takes up the knotty issue of the unity of experience through time. Some historical proposals are considered here and a new theory developed. Chapter 5 turns to the case of people whose corpus callosum has been severed, thereby splitting the two hemispheres of the brain. On the basis of the anomalous behavior such individuals exhibit in special experimental settings, they are usually taken to have a divided or disunified consciousness. Sometimes, it is suggested that they are really two persons. An account is proposed and defended of the consciousness of split-brain patients, and it is argued that certain facts about these patients supply further support for the theory of unity on offer. Finally, in chapter 6, the nature of persons and personal identity is discussed. Some connections are drawn between the issue of identity and that of unity; the discussion also provides further theoretical underpinning for some of the claims about persons in chapter 5. The two great historical theories of the nature of persons—the ego theory and the bundle theory—are found lacking for various reasons, and a new proposal is made. The last part of the chapter takes up the difficult question of whether there can be indeterminacy in personal identity. Here it proves necessary to dangle a toe or two into the quicksand of vagueness; but, given the focus of the book, I resist the temptation to go any deeper.
xiv
Preface
In my last two books, I laid out and defended the representationalist view of phenomenal character. That view is directly relevant to the proposals made in this book. However, it is not necessary to endorse the specific theory I take of the phenomenal character of experience in order to find my ideas on unity agreeable. Representationalism is a very general theory. For example, it involves no direct commitment to physicalism and it takes no direct stand on the nature of content. Those who finds themselves attracted to the representationalist view of phenomenal consciousness, even if they are unpersuaded by the specific form of the view I endorse, should still find the current proposals about unity of value. Those who are disinclined to accept even a nonreductive form of representationalism may nonetheless find food for thought in the book; for the simple and appealing way in which representationalism comes to grips with unity provides further reason to take the theory seriously. Since it may not be fully clear just what the commitments of representationalism are, I have included an appendix on representationalism. This appendix locates my version of representationalism within the space of alternative possible accounts of the theory and it reminds the reader that representationalism comes in many varieties. I have given talks on chapters from the book at many places in the United States and the U.K., and I am indebted to a large number of people for helpful comments. I recall in particular remarks by Bob Adams, Kati Balog, Alex Byrne, David Chalmers, Jim Dye, Bob Hale, Shelley Kagan, Sean Kelly, Bob Kuehns, Fiona Macpherson, David Pitt, Joseph Raz, Stephen Read, Mark Sainsbury, Sydney Shoemaker, Susanna Siegel, Charles Spence, Leslie Stevens, Daniel Stoljar, Scott Sturgeon, Jerry Vision, and Crispin Wright. I am also indebted to Jim Gibbs for drawing the cartoons.
Preface
xv
The material in the book is new with the exception of part of the introduction, which incorporates (with revisions) some of my “The Burning House,” in Conscious Experience (1996), edited by T. Metzinger, and most of section 5 in chapter 6, which draws on my “Vagueness and Reality,” Philosophical Topics 28 (2001).
Introduction: Kinds of Unity and Kinds of Consciousness
I.1 Preliminary Remarks The thesis that consciousness is necessarily or essentially unified plays a central role in Descartes’s writings and also in those of Kant. Descartes took this to have significant implications for whether the mind is a material thing; for, according to Descartes, consciousness is the essence of the mind and any material entity is separable into distinct parts. Kant wisely resisted any such inference. In his view, it is no less puzzling how an immaterial entity without parts could have a unified consciousness than a material entity with parts or components acting together. Recent work in neuropsychology on subjects whose brains have been bisected seems to undercut the thesis that Descartes and Kant shared. These subjects behave in ways that are often taken to show that their consciousness is disunified. Some contemporary philosophers (Dennett, for example) even hold that consciousness is frequently disunified. What makes the evaluation of claims such as these difficult is that there is no one kind of consciousness and there is no one kind of unity. I shall not attempt here to draw up an exhaustive list of kinds of consciousness or unity. But it will be useful to
2
Introduction
distinguish some common kinds, if the main focus of this book is to be properly grasped. I begin by presenting a number of ordinary, everyday cases, in some of which we normally suppose that consciousness is present while in others we deny it. The purpose of these cases is to distinguish between several different kinds of consciousness. The distinctions I draw reflect how we ordinarily think about consciousness. In this way, they are conceptual distinctions. I.2 Cases of Consciousness (or Its Absence) Case 1: The Distracted Philosopher Walking along the road, I find myself lost in thought for several hundred yards, as I make my way home. During this time I manage to keep myself on the sidewalk, but I am not conscious of how things look to me as I walk along. Later on, I “come to” and realize that I have been walking for some time without any real consciousness of my perceptions.1 Case 2: The Bird-watcher You and I are both bird-watchers. There is a bird singing in a tree nearby. We both hear it, but only you initially are conscious of it by sight. You tell me exactly where to look, and I stare at the right part of the right branch. My retinal image is, let us suppose, just the same as yours when I stand in the spot you are located and look in the same direction. But I report to you that I am not visually conscious of any bird.2 Case 3: The Wine Taster Apprentice wine tasters are much less discriminating than experts. Through training they come to discriminate flavors
Kinds of Unity and Kinds of Consciousness
3
that initially seemed to them to be the same. They become conscious of subtle differences in wines of which they were not previously conscious. Case 4: The Brief Encounter You are looking at a shelf on which there are eighteen books. Your eyes quickly pass over the entire contents of the shelf. You see more than you consciously notice. Indeed, you see all the books (let us suppose). But you are not conscious of how each of the books looks. Case 5: The Headache That Won’t Go Away You have a bad headache, which lasts all afternoon. From time to time during the afternoon, there are distractions. You think of other things, you forget for a few moments. In short, you are not always conscious of your headache. When this happens, we do not infer that really you had one headache that ceased at the first distraction, then another quite different headache until the next distraction, so that you were really subject to a sequence of discontinuous headaches.3 Case 6: The Pain in the Night I am fast asleep. During the night I am awoken by a pain of which, before awakening, I was not conscious.4 Case 7: What It Is Like I smell a cigar smoldering; I feel a burning pain in my stomache; I taste some smoked salmon; I seem to see bright yellow. In each of these cases, I undergo a different feeling or
4
Introduction
experience. For feelings and perceptual experiences, there is always something it is like to undergo them, some phenomenal or subjective aspects to these mental states. They are inherently conscious mental states. Case 8: The Boring Shade of Blue I am staring at a wall that has been painted deep blue. My mind wanders for a few moments, and I am not conscious that I am undergoing a visual experience of blue. But the wall continues to look blue to me even when my mind is wandering. Case 9: The Party Animal I am at a party, and I have been drinking all night. Eventually, not long before dawn, I leave. Upon arriving home, I make my weary way to the kitchen and pass out on the kitchen floor. I lose all consciousness. Case 10: The Dreamer I am asleep, dreaming that I am being pursued by a pterodactyl that is swooping down on me with evil intent. Even though I am not awake, I am having conscious experiences. These experiences are real to me, so much so that I wake up in a panic. Case 11: The Sleeping Dog My dog is asleep. Her eyes are moving rapidly. As they do so, her nose twitches and she growls and shudders. She is having conscious experiences.
Kinds of Unity and Kinds of Consciousness
5
Case 12: The “Haunted” Graveyard One night I take a shortcut home and cross an old graveyard. I suddenly feel very afraid. I seem to smell a strange sweet odor in the air and to see a shape floating over a grave. Although I do not know it, I am hallucinating. I am fully conscious, but the conscious states I am in are delusive. What are the kinds of consciousness that these cases illustrate? I.3 Kinds of Consciousness In case 1, I certainly see the sidewalk ahead as I walk home, and I react accordingly. If this were not the case, I would bump into things or end up in the street. But I am not conscious of my perceptions. I am not aware of how things look to me on the sidewalk and road. I am distracted. The kind of consciousness the absence of which this case illustrates is that of introspective awareness. It is sometimes held that this sort of consciousness is solely a matter of its subject having a higher-order thought that he or she is undergoing a certain mental state, where this thought is not based on inference or observation (Rosenthal 1997). Another view is that introspective awareness, at least in the case of experiences and feelings, is a kind of secondary seeing-that or displaced perception (Dretske 1995; Tye 1995a, 2000). I shall have more to say about this view in chapter 1. A third view is that introspective awareness is a kind of monitoring of mental states much like perception via the senses but inwardly directed (Lycan 1997). For present purposes, it is not necessary to adjudicate between these accounts. Let us call the above kind of consciousness “introspective consciousness” or “I-consciousness” for short, however it is
6
Introduction
further analyzed. A distracted walker, then, has no I-consciousness of his visual perceptions. The cases of the bird-watcher and the wine taster (cases 2 and 3) illustrate what I shall call “discriminatory (or D-) consciousness.” The bird-watcher who is conscious of the bird has successfully picked it out cognitively from the branches and foliage in its immediate vicinity. Likewise, the wine taster who becomes conscious of certain differences in wines of which he was, earlier in his training, unconscious has noticed those differences. D-consciousness is a form of perceptual consciousness—a form that involves recognition of what is perceived. The party animal (case 9) lacks discriminatory consciousness with respect to anything external. He is not processing information about the external world and responding to it in a rational manner. Let us say that the general sort of consciousness lacked by the party animal is “responsive consciousness,” or “R-consciousness” for short. This sort of consciousness, I might add, can be partial: A person who is limited in his reactions upon opening his eyes in the morning after taking a heavy sleeping draught the night before is not fully R-conscious. There is much around him that he does not notice. R-consciousness, then, is a generalized version of D-consciousness. In case 4—the brief encounter—you see eighteen books, but, for some of the books, you are not conscious of your seeing them. This is an absence of I-consciousness. You also lack D-consciousness with respect to some of the books, since there are books you do not notice. In case 5, you have a headache of which you sometimes are not conscious. This again is the absence of I-consciousness, as is the following case of the pain that wakes you in the night. These two cases, however, strongly suggest another
Kinds of Unity and Kinds of Consciousness
7
kind of consciousness not yet distinguished. If you have a headache then you have a pain. And, intuitively, to have a pain is to undergo a certain sort of feeling. In case 5, then, there is a feeling without I-consciousness, and likewise in case 6 (the pain in the night) at least prior to waking up. But if there is a feeling, then there must be consciousness, in some sense of the term. For how could a feeling be a feeling and yet not be conscious at all? Call this sort of consciousness “phenomenal (or P-) consciousness.” A mental state may be said to be P-conscious if, and only if, it has a phenomenal character (or a subjective “feel”). Thus, a pain of which its subject is not I-conscious is nonetheless P-conscious. Via I-consciousness, the subject comes to know what it is like to have the pain, but what the pain itself is like—its phenomenal “feel”—is not a matter of I-consciousness. Exactly the same sort of situation obtains in case 8. There is nothing incoherent in supposing that something looks blue to me even though, owing to a distraction, I do not think or judge that it looks blue (or that it is blue).5 But if the wall before my eyes looks blue then I must be having a visual experience of blue. And if I am having a visual experience of blue, then I am in a conscious state representing blue. There is some phenomenal character to my visual state as I view the blue wall. Of course, if my mind is wandering, I will not be conscious (in the introspective sense) of this phenomenal character. But the wall, by hypothesis, continues to look blue. Had I introspected at the time at which my mind was wandering, I would have been aware that I was continuing to have a visual experience of blue. But I did not, in fact, then introspect. There is P-consciousness without I-consciousness. Suppose that on the wall in the center of my field of view there is an insect. Initially I notice the insect, but, as my
8
Introduction
mind wanders, for a moment or two I fail to notice it. Intuitively, I still see it, even though briefly I do not see that it is on the wall before me. But if I see the insect, it must look some way to me;6 and if it looks some way to me, it produces in me a conscious state. This state is P-conscious, but I am not D-conscious of the insect. P-consciousness is integral to experiences and feelings generally, as is noted in case 7. Wherever there is a feeling or experience, there must be P-consciousness, some phenomenology that the relevant state has. P-consciousness is often illustrated further by reference to the famous inverted and absent qualia hypotheses.7 The former of these hypotheses, for the case of color, is the claim that there might be someone whose color experiences are phenomenally inverted relative to those of others even though she uses color words and functions in color tests in all the standard ways. Here there is a phenomenal difference, that is, a difference in phenomenal consciousness, that is not manifested in any behavioral or functional differences. The latter hypothesis is the claim that there might be someone who felt or experienced nothing at all, someone who altogether lacked P-conscious states, but who functioned in just the same manner as someone who underwent such states. It is also in connection with P-consciousness that the suggestion arises that there is a huge explanatory gap. Physical changes in the gray and white matter composing our brains produce states that can be fully understood only by creatures that share our experiential perspective, states that have a “technicolor phenomenology” (as McGinn puts it in his 1991). There seems an immense gap here, something that cries out for explanation. Why does a given firing pattern generate a given feeling instead of a different one? Why
Kinds of Unity and Kinds of Consciousness
9
does that firing pattern produce any felt quality or subjective phenomenology at all? How can a state like pain, whose nature cannot be fully comprehended by someone who has never experienced it, be generated by objective, physical processes in the brain—processes whose nature is accessible from many points of view? P-consciousness, it should be noted, is a feature of mental states. I-, D-, and R-consciousness are different: they are properties of creatures. They are all forms of creature consciousness. Are they also forms of consciousness that could be present in a zombie, that is, a being who functionally is just like a sentient creature but who lacks any phenomenal consciousness? That depends. On one natural view of Dand R-consciousness, they are purely cognitive activities that are normally based on P-consciousness without inherently requiring it. In the case of I-consciousness, the relevant issue is whether introspection is necessarily accompanied by an inner phenomenology. However this is settled, a creature cannot be conscious in any of the three ways distinguished unless it undergoes mental states having conceptual contents that play a role in reasoning and the intentional control of behavior. Such states are sometimes said to be access conscious (Block 1993; also this vol., chap. 5, p. 123). If zombies are conceivable, then access consciousness can conceivably occur without phenomenal consciousness. Returning now to the adumbrated cases, we should note that P-consciousness is also present indirectly in case 4. Ex hypothesi, you see all the books. So, each book (briefly) looks some way to you as your eyes move along the shelf. In having visual experiences of books that you do not notice, you are subject to a kind of visual consciousness. There is thus something it is like for you at each moment as your eyes scan the contents of the shelf. What it is like changes,
10
Introduction
even if you are not introspecting and you are not cognizant of all the changes. Your visual experiences are phenomenally conscious.8 There is one complication worth mentioning here. Perhaps in some cases the act of introspection itself causally impacts the phenomenal character of the introspected state, so that what it is like to undergo the state then changes with the act of introspection. For example, suppose I have a toothache that persists all evening. There are times at which I am not conscious of it. At other times, I am conscious of it and I attend carefully to how it feels. Perhaps the act of attention changes to some extent the phenomenal character of the toothache. That at least seems conceivable. If so, then the attended phenomenal character is different from the unattended one. In case 10 (the dreamer), my experiences are P-conscious. There is something it is like for me in dreaming of the pterodactyl. But I am not R-conscious. I am not processing information about the external world and responding to it in a rational manner. So, there is nothing real with respect to which I am D-conscious. Need there be I-consciousness? If I wake up in a panic, to some significant degree I must believe that I am in a situation that is dangerous to me. But I need not believe or think that I am having a visual experience as of a pterodactyl, even if I do believe that I am being pursued by a pterodactyl. So long as the latter belief is present, it will cause in me fright. The former belief or thought, which is higher-order and hence more complicated contentwise, is not necessary. So, at least on accounts of introspection that require such a higher-order state, I-consciousness need not be present. This conclusion is reinforced by case 11. It seems to me plausible to suppose that dogs that growl during REM sleep
Kinds of Unity and Kinds of Consciousness
11
are subject to P-conscious states that cause beliefs about things in the world or people (for example, a coveted bone or a postman). But it seems much less plausible to suppose that in each and every such case, a higher-order belief or thought must be present. Surely, one important difference between humans and other animals is that the former are much more reflective than the latter. There is certainly P-consciousness, however. It would be absurd to suppose that there is nothing it is like for a dog that chews a favorite bone or prefers chopped liver for its dinner over anything else it is offered. Case 12 is similar to case 11. Although I am hallucinating, I am still undergoing sensations and perceptual experiences. My experiential states are P-conscious: there is something it is like for me as I feel afraid, as I seem to smell a strange odor, and as I seem to see a white shape. But in this case I am also R-conscious. For I am awake and cognitively processing information from my surroundings. Of the kinds of consciousness illustrated by the above examples, by far and away the most problematic is P-consciousness; for it is in connection with P-consciousness that the really difficult philosophical puzzles and conundrums arise. It is also in connection with P-consciousness that the sort of unity that will concern us in this book is found. I.4 Kinds of Unity One important issue of investigation recently in cognitive psychology and neurophysiology has been how the visual system brings together information about shape and color. If I view a green, circular object, the greenness and roundness I experience are represented in different parts of my visual system. In my experience, however, the color and shape are unified. I experience a single green, circular object. I notice and
12
Introduction
report on only one such object. How can this be? How are the color and shape unified as belonging to a single object in my consciousness? This is often called “the binding problem” and the kind of unity it concerns is object unity.9 Object unity is not a necessary feature of P-consciousness. We frequently experience colors and shapes without experiencing them as belonging to the same object, as when, for example, I see a green object next to a round one without seeing a green, round object. So, colors and shapes need not be object-unified in my consciousness as I undergo a P-conscious state. A second kind of unity is neurophysiological unity. Conscious states may be said to be neurophysiologically unified if and only if they are realized in a single neural region or via a single neurological mechanism. A third sort of unity is spatial unity. Consciousness is spatially unified for a given subject if and only if everything experienced by that subject is experienced as belonging to a single, common space. Spatial unity can obtain at a time or through time; it can obtain for consciousness of one sort while failing for consciousness of another. The view that perceptual consciousness is necessarily spatially unified is quite plausible; and it has had some distinguished advocates (most notably Kant). A fourth kind of unity is subject unity. Two different states of consciousness may be said to be subject unified if and only if they are undergone by the same mental subject. These states could be higher-order ones, involved in I-consciousness, or they could be first-order states. Whatever the states, the thesis that, for any given subject, all his or her states of consciousness are subject unified is trivially true. Kant held that the unity of consciousness involves having experiences that the subject of the experiences can self-ascribe
Kinds of Unity and Kinds of Consciousness
13
in thought. This ties the unity of experience to the subject via higher-order consciousness. Let us call this unity higherorder subject unity. Consciousness is higher-order subjectunified for a given subject (at a given time or for a given period of time) if and only if that subject can self-ascribe each of her conscious states in thought (at that time or for that period). Higher-order subject unity is thus much more demanding than subject unity. Another related thesis is that two states of consciousness are unified if and only if the subject can introspect both states in a single act of introspective awareness. This is introspective unity. Gestalt unity is the sort of unity that obtains if and only if the experience of a whole is such that had one salient part of the whole been removed from consciousness, the experience would have had a radically different phenomenal character. For example, on one natural way of seeing figure I.1, the viewer has an experience of a vase; but if the right half is removed, the experience becomes one of a face, in profile, turned to the right. Gestalt unity is an interesting phenomenon, the principles of which have been studied in detail by psychologists. It is more the exception than the rule, however. For example, removing a part of figure I.2—the left half, say—does not produce an experience of a whole with a radically different character. And with intermodal cases, there are few Gestalt effects.10 The final kind of unity I shall distinguish is phenomenal unity. Phenomenal unity is present in all normal cases of phenomenal consciousness. It is usually taken to be a property of experiences or P-conscious states; in my view, it is different from object unity, neurophysiological unity, spatial unity, subject unity, higher-order subject unity, introspective
14
Introduction
Figure I.1
Figure I.2
Kinds of Unity and Kinds of Consciousness
15
unity, and Gestalt unity. Phenomenal unity is the kind of unity with which this book is concerned. In chapter 1, a number of examples of phenomenal unity are adduced, with the aim of clarifying what is involved for the case of perceptual experience at a single time, and a theory is offered of synchronic, perceptual, phenomenal unity.
1
The Unity of Perceptual Experience at a Time
1.1 Multiple Experiences and the Problem of Unity (1) It is widely supposed in both philosophy and psychology that the senses function as largely separate channels of information that generate different sense-specific impressions or experiences. For example, I see some flowers, a fence, and two squirrels, and in seeing them, I undergo visual experiences. Listening to a nearby bird singing, I hear melodious sounds, and in so doing, I am the subject of auditory experiences. Finding a broken egg on the ground and smelling its pungent odor, I experience olfactory experiences. Placing a chocolate in my mouth and tasting its sweetness, I have gustatory experiences. Running my fingers over the bark of a tree and feeling its roughness, I experience tactual experiences. (2) So, according to the received view, if I am using all five of my senses at a given time, I undergo five different simultaneous perceptual experiences at that time, each with its own distinctive sense-specific phenomenal character. This generates one version of the problem of the unity of conscious experience. How is it that if I am undergoing five
18
Chapter 1
different simultaneous perceptual experiences, it is phenomenologically as if I were undergoing one? How is it that the five experiences are phenomenologically unified? (3) Suppose that at midday a wine taster is tasting a Cabernet Sauvignon. He sees the red wine in the wineglass beneath his nose, as he brings the wine to his lips. He smells the rich bouquet of the wine, as he tastes its fruity flavor in his mouth; and in tasting it, he experiences the liquid touching his tongue and the back of his mouth. Perhaps, as he does this, he flicks a finger against the glass, thereby producing a high-pitched sound. One way to describe the wine taster’s phenomenal state is to say that he has an experience of a certain colored shape and further he has an experience of a certain smell and in addition he has an experience of a taste and . . . etc. But intuitively, this is unsatisfactory. It leaves something out: the unity of these experiences. There is something it is like for the wine taster overall at midday, as he brings the wine to his lips and smells and tastes it. There is a unified phenomenology. How can this be, if, in reality, he is undergoing five separate experiences? Of course, for each of these experiences, there is something it is like to undergo the experience. But there is also something it is like to have these experiences together. And that remains to be accounted for. (4) Here is another example. Holding a ripe apple in my hand, I experience a red surface and I experience a cold surface. These experiences aren’t experienced in isolation, however. They are experienced together. This is part of the phenomenology of my experience overall. There is a unity in my experience. In what does this unity consist, given that I am subject to two different token experiences, one visual and one tactual?
The Unity of Perceptual Experience at a Time
19
(5) Phenomenal unity is not simply a matter of the relevant experiences being directed on a single object in a spatially localized region. For one thing, in the wine taster case, although the wine he sees is in the glass, the wine he tastes is in his mouth. For another, the phenomenological unity of experiences to which I am referring can occur even with experiences directed on widely separated objects. Standing by the railing of a ship and smelling the sea air, as I look at the ship’s wake in the ocean, I may hear the sound of a tugboat on my left some distance away. Again, my overall experience is unified. It forms a seamless phenomenal whole within which smell, sound, and various visual qualities are phenomenologically present. Phenomenal unity thus is to be distinguished from object unity. (6) The phenomenal unity of simultaneous experiences is also not a matter of their being actual or potential objects of a single act of the subject’s attention. Allowing for the moment that subjects can attend introspectively to their experiences,1 intuitively the unity of simultaneous experiences can exist even without the introspective attention, just as the experiences can. Walking along a lane filled with leaves, you see many more leaves than you notice. If your interest is held by one large, yellow and brown, star-shaped leaf, you do not cease to see the other leaves. They do not vanish from your visual experiences. They simply recede into the phenomenal background. Likewise if some nesting birds nearby take flight and you are struck by one shrill sound in particular. The other sounds are still there in the phenomenal background of your auditory experience. Corresponding points apply to the phenomenal unity of experiences. Intuitively, this unity is not created by the act of introspective attention. Rather, it is revealed or disclosed.
20
Chapter 1
If this is so, then phenomenal unity is not the same as introspective unity.2 (7) This point also undermines the view, historically popular, that unity is imposed on the different sense experiences by thought, insofar as this view is supposed to account for phenomenal unity. The Kantian suggestion that experiences are unified by the capacity of their subjects to think of them as their own fails to come to grips with the intuitive fact that phenomenal unity is there in the experiences, whatever their subjects can or cannot think. It is certainly true that without the relevant concepts, a person cannot recognize that there is phenomenal unity and thus, in these circumstances, he or she is “blind” to it. But the unity itself is not a cognitive matter. It is also worth noting that Kant’s proposal, insofar as it is applied to the case of phenomenal unity, is in trouble anyway with respect to the case of splitbrain patients who are certainly able to self-ascribe their perceptual experiences, but whose experiences, after the commissurotomy, are phenomenally disunified in certain special experimental situations.3 (8) If there really is something it is like to undergo all the sense-specific experiences together at the same time—if there really is a phenomenological unity—then there must be an encompassing experience, one that includes the other experiences within itself. That experience is the bearer of the total, unified phenomenology. (9) Note that this experience cannot just be a conjunction of the five modality-specific experiences. The conjunction of two experiences isn’t itself an experience at all. The maximal experience must be a new experience, one that unifies the other experiences into a single phenomenological whole. As Bayne and Chalmers put the point in a recent discussion:
The Unity of Perceptual Experience at a Time
21
At any given time, a subject has a multiplicity of experiences. . . . These experiences are distinct from each other. . . . But at the same time, . . . they seem to be unified, by being aspects of a single encompassing state of consciousness. (2003, p. 23) . . . this encompassing state of consciousness . . . can be thought of as involving at least a conjunction of many more specific conscious states. . . . But what is important, on the unity thesis, is that this total state is not just a conjunction of conscious states. It is also a conscious state in its own right. (Ibid., p. 27)
(10) That experiences bundle together to form overarching experiences is a view that has counterparts, of course, within each sense. For there is phenomenal unity not just across senses but within them too. Thus, Wilfrid Sellars (1968, p. 27) remarks: “A sense-impression of a complex is a complex of impressions.” Likewise, Sydney Shoemaker (1996, p. 177) says: “. . . the visual experience of a spatially extended thing is a synthesis of visual experiences of parts of that thing.” (11) Seen from this vantage point, the problem of the unity of conscious experience, as it applies to the case of simultaneous perceptual experiences, is, first and foremost, to give an account of the nature of the unifying experience in relation to the other experiences. 1.2 Undermining the Problem as Standardly Conceived (12) The problem, stated in this way, is threatened by an infinite regress. If what it is like to undergo the overall or maximal experience is different from what it is like to undergo the component sense-specific experiences, E1–E5, then there must be a unifying relation between the latter experiences that is itself experienced. The experience of the unifying relation is not itself a sense-specific experience. But
22
Chapter 1
it is an experience nonetheless; for if there were no experience of the unifying relation, then there would be nothing it is like to have the sense-specific experiences unified. There are, then, it seems, six experiences: the five sense-specific ones and the experience of unity. However, the maximal experience isn’t just a conjunction of experiences. It is a genuinely new unified experience with its own phenomenology. So, what unites the six experiences together? It seems that there must be a further unifying relation that binds the experiences. This relation, however, must itself be experienced. For the unity is phenomenal. And now a regress has begun to which there is no end. (13) There is also a real question as to whether there is a maximal, unifying experience in the first place. For consider three simultaneous unified experiences, e1, e2, and e3. If the unity or experienced togetherness of any two experiences requires that there be a unifying experience, then the unity of e1 and e2 requires a further experience E that includes them. Since E is unified with e3, another experience E is now required. But E is also unified with E; so a further experience, E, that includes E and E is needed. And the unity of E with E and E necessitates yet another experience; and so on, without end. (14) Another pressing difficulty is that we are not introspectively aware of our experiences as unified; for we are not aware of our experiences via introspection at all. This needs a little explanation. Suppose that you have just entered a friend’s country house for the first time and you are standing in the living room, looking out at a courtyard filled with flowers. It seems to you that the room is open, that you can walk straight out into the courtyard. You try to do so and, alas,
The Unity of Perceptual Experience at a Time
23
you bang hard into a sheet of glass, which extends from ceiling to floor and separates the courtyard from the room. You bang into the glass because you do not see it. You are not aware of it; nor are you aware of any of its qualities. No matter how hard you peer, you cannot discern the glass. It is transparent to you. You see right through it to the flowers beyond. You are aware of the flowers, not by being aware of the glass, but by being aware of the facing surfaces of the flowers. And in being aware of these surfaces, you are also aware of a myriad of qualities that seem to you to belong to these surfaces. You may not be able to name or describe these qualities but they look to you to qualify the surfaces. You experience them as being qualities of the surfaces. None of the qualities of which you are directly aware in seeing the various surfaces looks to you to be a quality of your experience. You do not experience any of these qualities as qualities of your experience. For example, if redness is one of the qualities and roundness another, you do not experience your experience as red or round. If your friend tells you that there are several ceiling-tofloor sheets of glass in the house and that they all produce a subtle change in the light passing through them so that things seen the other side appear more vividly colored than is usually the case, as you walk gingerly into the next room, you may become aware that there is another partitioning sheet of glass before you by being aware of the qualities that appear to belong to nonglass surfaces before your eyes. You are not aware of the second sheet of glass any more than you were aware of the first; but you are now aware that there is a sheet of glass in the room by being aware of qualities apparently possessed by nonglass surfaces before you. Visual experiences are like such sheets of glass. Peer as hard as you like via introspection, focus your attention in
24
Chapter 1
any way you please, and you will only come across surfaces, volumes, films, and their apparent qualities. Visual experiences are transparent to their subjects. We are not introspectively aware of our visual experiences any more than we are perceptually aware of transparent sheets of glass. If we try to focus on our experiences, we “see” right through them to the world outside. By being aware of the qualities apparently possessed by surfaces, volumes, etc., we become aware that we are undergoing visual experiences. But we are not aware of the experiences themselves.4 This is true, even if we are hallucinating. It is just that in this case the qualities apparently possessed by surfaces, volumes, etc., before our eyes are not so possessed. The surfaces, volumes, etc., do not exist. (15) Introspection, on the view just presented, is significantly like displaced perception or secondary seeing-that, as Fred Dretske (1995) has observed. When I see that the gas tank is nearly empty by seeing the gas gauge or when I see that the door has been forced by seeing the marks on the door, I do not see the gas tank or the forcing of the door. My seeing-that is secondary or displaced. I am not aware—I am not conscious—of either the gas tank or the forcing of the door. I am aware of something else—the gas gauge or the marks on the door—and by being aware of this other thing, I am aware that so-and-so is the case. Similarly, in the case of introspection of a visual experience, I am not aware or conscious of the experience itself. I am aware that I am having a certain sort of experience by being aware of something other than the experience—the surfaces apparently outside and their apparent qualities.5 (16) What is true above for the case of vision is true for the other senses. For example, we hear things by hearing the sounds they emit. These sounds are publicly accessible.
The Unity of Perceptual Experience at a Time
25
They can be recorded. Similarly, we smell things by smelling the odors they give off. They too are publicly accessible. You and I can both smell the foul odor of the rotting garbage. Odors, like sounds, move through physical space. We taste things by tasting their tastes. One and the same taste can be tasted by different people. Some tastes are bitter, others are sweet. When we try to introspect our supposed experiences of hearing, smelling, and tasting, the qualities of which we are directly aware are qualities we experience as being qualities of sounds, odors, and tastes. It seems very natural to suppose that among these qualities are the following: pitch, tone, loudness, pungency, muskiness, sweetness, saltiness, sourness. But be that as it may, the important point is that when we introspect, the particulars we come across, if any, are sounds, odors, and tastes—the owners, if such exist, of the qualities we find in introspection. We do not come across, in addition to these things, token experiences of hearing, smelling, and tasting. Nor do we come across any overarching or maximal token perceptual experience. (17) If we are not aware of our experiences via introspection, we are not aware of them as unified. The unity relation is not given to us introspectively as a relation connecting experiences. Why, then, suppose that there is such a relation at all? (18) These points serve to remind us that one way to respond to a philosophical problem is to challenge the problem itself instead of accepting it, on its own terms, and trying to solve it. 1.3 The One Experience View (19) Consider the following example (from Parsons 1972) as a way of beginning to get at what seems to me wrong.
26
Chapter 1
Suppose that this statement is true: (S) Jones writes illegibly and Jones writes painstakingly. It does not follow that (S*) Jones writes illegibly and painstakingly, at least on one natural reading of (S*). For if Jones writes illegibly but not painstakingly with his left hand and painstakingly but legibly with his right, then (S) is true but (S*) false. In this case, there is an event of Jones’s writing illegibly and there is an event of Jones’s writing painstakingly, but these are two distinct events. There is no event of Jones’s writing both illegibly and painstakingly. So, (S) does not entail (S*), but (S*) clearly does entail (S). Given the event of Jones’s writing both illegibly and painstakingly, there is, of course, the event of Jones’s writing illegibly. For the latter is the very same event as the former under a less broad description. Likewise for the event of Jones’s writing painstakingly. (20) In the case where (S*) is true, there is a kind of unity to Jones’s writing. Illegibility and painstakingness are combined together in a single instance of writing. That unity is lacking in the case that (S) is true and (S*) is false. But where (S*) is true, there are not two different writings, one painstaking and the other illegible, which somehow are unified together to produce a third, overarching writing that includes them. There is just one writing that may be described in more or less encompassing ways.6 To suppose otherwise is to create a new pseudo-problem: the problem of the unity of the event of Jones’s writing illegibly and painstakingly. (21) Here is another example. Suppose it is lunchtime and I have a sudden and strong desire for a pint of beer with a
The Unity of Perceptual Experience at a Time
27
ham sandwich. In having this desire, of course, I have a desire for a pint of beer. It is also true that I have a desire for a ham sandwich. But patently I don’t have three sudden desires here. Nor is it the case that having a desire for a beer together with a desire for a ham sandwich just is having a desire for a pint of beer with a ham sandwich. I might want a beer and also want a ham sandwich while finding the idea of having the two together repellent. My sudden desire for a pint of beer with a ham sandwich is a single desire that can be described in multiple ways. The description ‘desire for a pint of beer’ is incomplete, but unlike the description ‘desire for a pint of beer alone’, it is not inaccurate. (22) These remarks apply mutatis mutandis, I want to suggest, to the problem of the unity of conscious experience, as it is usually conceived. There are not five different or separate simultaneous experiences somehow combined together to produce a new unified experience. Nor are there are multiple simultaneous unified experiences within each sense. To be sure, if I am the wine taster, the statement (S!) I have an experience of a bright red shape and I have an experience of a fruity taste and I have an experience of a cassis odor . . . is true. And, given that the case is one of phenomenal unity, the following is true too: (S#) I have an experience of a bright red shape and a fruity taste and a cassis odor . . . Moreover, (S#) entails (S!). But there is just one experience here, an experience that can be described less fully as my experience of a bright red shape or as my experience of a fruity taste, etc.
28
Chapter 1
(23) On this view, there really are no such entities as purely visual experiences or purely auditory experiences or purely olfactory experiences in normal, everyday consciousness. Where there is phenomenological unity across sense modalities, sense-specific experiences do not exist. They are the figments of philosophers’ and psychologists’ imaginations. And there is no problem, thus, of unifying these experiences. There are no experiences to be unified. Likewise within each sense: there are not many simultaneous visual experiences, for example, combined together to form a complex visual experience. There is a single multimodal experience, describable in more or less rich ways. (24) “Stuff and nonsense,” you may say. “The proposal is empirically false. Visual experiences are known to arise in the visual cortex, auditory experiences are known to arise in the auditory cortex, and so on. In the wine taster case, it is surely undeniable that visual experiences are tokened in the wine taster’s visual cortex, as he views the wine he is tasting, experiences of just the same phenomenal type as those that would have been tokened in that cortex had the situation been the same but his other senses blocked from any information. Of course, these experiences exist!” (25) By way of reply, let us for a moment indulge in the fiction that there are purely visual experiences in everyday consciousness of the external world. In these experiences, shape and color are unified. If, for example, I view a green square, my visual system represents the greenness and the squareness in separate places in the brain; but these qualities aren’t experienced as separate. They are experienced as qualities of a single thing. I have an experience that is objectunified, as we might say, even though its physical basis is disunified.7 What is the relationship between the experience
The Unity of Perceptual Experience at a Time
29
and its physical basis? The answer I favor is that the experience, assuming there is one, is constituted by a certain combination of separate and largely independent physical events in the visual cortex, but it is not token identical with that combination. This answer gives the experience a physical nature; moreover, constitution is the relation that bonds macro-events and micro-events, macro-states and microstates, macro-objects and micro-objects generally. Consider, for example, a single cloud in the sky. The cloud is an aggregate of water droplets. The ‘is’ in the last sentence is not the ‘is’ of identity. The cloud in the sky could survive the loss of a few of its constituent water droplets (if, say, a highly localized strong gust of warm air were to cause them to evaporate). Not so any aggregate of water droplets that contains them. The loss of those droplets would destroy the original aggregate. So, the cloud has a modal property the aggregate of water droplets lacks, that of possibly surviving the loss of such-and-such droplets. It follows by Leibniz’s Law that the cloud is not identical with any aggregate of droplets. In general, ordinary, everyday macro-objects are not identical with aggregates of their parts, since the former differ in their modal properties from the latter. My car, for example, might have had a different carburetor, but the aggregate of its actual parts could not have failed to contain the actual carburetor. The car, thus, is not identical with the sum of its parts. The relationship rather is one of constitution or composition. One need not resort to modal properties to make the above points. Actual properties will do in some cases. The clay that constitutes a pot exists before the pot does. The lump of silver that is melted and formed into a coin exists before the melting process, but the coin does not. The clay is thus not identical with the pot; the lump of silver not identical with the coin.
30
Chapter 1
Likewise for macro-events. Consider the eruption of Mount Vesuvius. Intuitively, that very eruption might have spewed forth an imperceptibly smaller amount of lava. Had it done so, the micro-events taking place in the spatial region of Vesuvius’ eruption would have been minimally different, and thus the aggregate of those events in that counterfactual situation is not the same as the actual aggregate. The eruption, therefore, has a modal property that the underlying cluster of micro-events lacks, and the former is not identical with the latter. Alternatively, consider all the microphysical events that compose the emergence of North America (Burge 1986). Imagine that these events are embedded within a much larger land mass, so that in the counterfactual situation there is no such thing as North America and its emergence. Then the aggregate of micro-events has the property of possibly existing without North America; but the event of North America’s emerging does not. That event is not identical with the aggregate. The aggregate constitutes the emergence of North America in actual fact, but the relationship is not one of identity. (26) Consider next the following example. A large chunk of clay is used to make a statue at time t. The clay constitutes the statue without being identical with it. Suppose counterfactually that at time t, where t is later than t, an artist cleverly removes much of the clay without remolding it so as to leave behind a small clay pot. In the counterfactual situation, the clay that remains constitutes a pot at t. But in the actual situation it does not. In actual fact, no clay is removed. There is, in actual fact, no tiny pot within the statue. There is only the statue. Within the aggregate of lumps of clay composing the statue, there is a smaller aggregate of clay lumps that in a
The Unity of Perceptual Experience at a Time
31
certain counterfactual situation composes a pot. In actual fact, the smaller aggregate does not compose a pot. Indeed, it does not by itself actually compose or constitute any ordinary thing. Rather, that aggregate and the remaining aggregate form a larger aggregate that composes the statue. (27) I hope that the relevance of all of this is becoming clear. On my view, at the given time the wine taster is subject to a single experience that represents the color of the wine, the sound of the wineglass, as it is flicked, the smell of the wine, and so on. This experience is constituted by a combination of largely independent physical events going on in separate regions of the brain. Within that combination of events, there is a cluster of events (call it C) occurring in the wine taster’s visual cortex. In the extraordinary counterfactual situation in which the wine taster’s nonvisual senses are all blocked so that no nonvisual information gets in, the wine taster is left with a purely visual experience. And in that counterfactual situation, C, in the absence of the other pertinent actual physical events, constitutes a visual experience. But it does not follow from this that in actual fact C constitutes a purely visual experience. In actual fact, C (wholly) constitutes no experience at all. There is just one unified experience the wine taster undergoes, and C, in conjunction with the relevant events in the auditory cortex, the olfactory cortex, and so on, constitutes that. (28) Perhaps it will be replied that in the example of the statue and the pot, the aggregate of lumps of clay that counterfactually constitutes the pot is in the actual world a purely arbitrary part of the statue, with nothing to mark it out from any number of other arbitrary parts of the statue. However, the cluster of physical events I have labeled ‘C’ is a nonarbitrary part of the relevant totality of physical
32
Chapter 1
events, a token of a physical type with a definite functional role, namely, to generate a conscious visual experience with a certain visual unity. (29) This reply begs the question. I grant that C is a token of a physical type P whose role in a normally functioning brain is to endow the conscious experience of the subject with a visual phenomenology. But that is certainly compatible with denying that P’s role is to generate in the brain a token experience with an exclusively visual phenomenology. To suppose that P’s role is the latter is to take for granted the truth of the view I am opposing. (30) Furthermore, the fact that C is a nonarbitrary part of the whole combination of physical events constituting the experience is not to the point. Suppose events E1 and E2 together actually constitute event F. Suppose E1 could have occurred without E2 and further that had E1 done so, it would have (wholly) constituted event G. Still, this is no guarantee that E1 actually constitutes G. For example, my arm and hand movement relative to Smith and Smith’s arm and hand movement relative to me constitute a certain fight. Smith’s movement might have occurred without my movement. Had it done so, it would have constituted an act of aggression on the part of Smith. But in actual fact that act of aggression does not exist. In actual fact, Smith’s arm and hand movement relative to me is a counterpunch; for I hit Smith first. Thus, just as Smith’s arm and hand movement might have constituted an act of aggression although in reality it does not, so too the cluster of events, C, might have constituted a purely visual experience although in reality it does not. (31) Suppose now that the counterfactual situation I have envisaged for C becomes a reality. As the wine taster tastes
The Unity of Perceptual Experience at a Time
33
the wine, some extraordinary neural malfunction causes the events other than C that constituted the wine taster’s experience prior to the malfunction to cease. Before the malfunction, on the proposed view, C does not constitute a purely visual experience. After the malfunction, it does. This, it may be charged, is strange. Why the radical change in what C does? (32) The answer, as earlier, is that there is no change. Before and after the malfunction, C does the same thing: It endows the conscious experience of the subject with a visual phenomenology. The difference is that before the malfunction, the experience of the wine taster does not have a purely visual phenomenology; after the malfunction, it does. (33) Consider next the following example. Suppose I hear a conversation on my left, as I look at a bed of roses laid out in front of me. Intuitively, my auditory experience—that very experience—could have occurred without my visual experience. On my account, however, that isn’t possible. So much the worse, it may be said, for my account! (34) Too fast, I reply. When I try to introspect my auditory experience, I fail. As noted earlier, what I actually come across are the sounds and the auditory qualities the experience represents. By being aware of those sounds, I am aware that I am undergoing an auditory experience. But I am not aware of the token vehicle of that content. The sounds I experience could have existed without my visual experience of the roses. Moreover, I could certainly have undergone an experience that represented those sounds (or sounds just like them) without also representing the colors and shapes of roses. That, I suggest, is all that untutored intuition requires here, once we are clear on what introspection does and does not reveal. And it is perfectly compatible with
34
Chapter 1
these claims that I am the subject of just one experience, an experience that is audiovisual in character. (35) But what if my auditory experience goes on longer than my visual experience? Then my auditory experience has a temporal property my visual experience lacks, and there cannot be a single experience after all. (36) I grant that I can experience a sound that continues, in my experience, after I experience anything visually. But this is all in the content of the experience. Initially, what I experience is that a sound with a certain pitch and loudness is accompanied by a certain color and shape. As time goes on, the experienced content changes. No longer is any shape or color represented. The sound is represented on its own. This certainly shows that the represented sound is not the same as the represented shape or color. But it does not show that there is more than a single experience at a time. I do not deny, of course, that difficult questions arise concerning the individuation of experiences through time. Is the experience I undergo initially—an experience with an audiovisual content—the same as the experience I undergo after the color and shape cease? Is there one experience here with a less rich content through time? Or is the audiovisual experience replaced by a second purely auditory experience, phenomenally just like the first in its auditory dimension? Hard questions of individuation through time arise for everyone, however. They are discussed further in chapter 4. (37) Here is a further worry. Seeing something entails the presence of a visual experience. I cannot see X unless X looks some way to me; and for X to look some way to me, it must cause in me a visual experience. So, to return to the
The Unity of Perceptual Experience at a Time
35
example of the wine taster, since he is seeing the wine in the glass, he must be subject to a visual experience. However, on the account I am adopting, his experience isn’t really properly classified as visual at all. (38) It is indeed true that X cannot look some way to person P unless X produces in P an experience with a visual phenomenology. But the phenomenology of P’s experience need not be purely or exclusively visual. It can be partly auditory, olfactory, gustatory, and tactual too. If a visual experience is understood to be an experience with a visual phenomenology, then the wine taster, as he sees the wine in the glass, is subject to a visual experience. It’s just that that very experience has a phenomenology that is auditory, olfactory, gustatory, and tactual as well. (39) Still, it may be complained, on the one experience view, no explanation is possible for why the beliefs formed directly on the basis of experience are about how things look, or how they taste or how they smell, rather than about some combination of these. My response is to deny the datum. We can know directly that the object looks red and is apparently emitting a loud sound, just as we can know directly that the object looks red and looks round. We have the ability to attend all at once to qualities, the experience of which (in some cases) requires the use of different senses. Indeed, it is the exercise of this ability that leads us to think that there is such a thing as synchronic unity in perceptual experience in the first place. In everyday life, we say things like “The drink looks creamy and it tastes sweet” and “The exhaust smells noxious and it sounds loud.” The beliefs these remarks express are no less cautious or direct than the belief expressed by, for example, “The card looks square and silvery in color.”
36
Chapter 1
1.4 An Account of Synchronic Phenomenal Unity (40) If the view of experience I have been defending is correct, then in ordinary, everyday perceptual consciousness, there are no sense-specific experiences to be unified. So, the problem of unity stated earlier dissolves. I do not wish to deny, however, that synchronic phenomenal unity is real. (41) The core intuition, lost in the usual way of stating the problem of unity, is that, in normal cases, simultaneously experienced perceptual qualities—the loudness of a sound, the smoothness of a surface, the sweetness of a taste, the pungency of a smell—are experienced together and thus are phenomenologically unified. These qualities are not qualities of experiences. They are qualities that, if they are qualities of anything, are qualities of things experienced. Consider, for example, the case in which I experience a loud noise and a bright flash of light. The loudness of the noise is unified phenomenally with the brightness of the flash. Phenomenal unity is a relation between qualities represented in experience, not between qualities of experiences. (42) Specifically, phenomenal unity is a matter of simultaneously experienced perceptual qualities entering into the same phenomenal content. The perceptual experience a normal perceiver undergoes has an enormously rich, multimodal representational content—a content part of which is nonconceptual, abstract, and appropriately poised.8 This part, its phenomenal content, is present not only in veridical cases but also in cases of illusion and hallucination. It is this content that endows the experience with its phenomenal character (Tye 1995a, 2000). (43) A consequence of the above position is that phenomenal unity goes with the closure of perceptual experience
The Unity of Perceptual Experience at a Time
37
under conjunction with respect to the unified qualities. Thus, in the case mentioned in (41) in which the loudness of a sound is phenomenally unified for person P with the brightness of a flash of light, the statements P has an experience of a loud sound and P has an experience of a bright flash jointly entail P has an experience of a loud sound and a bright flash. When there is disunity, perceptual experience is not closed in this way. Cases of simultaneous phenomenal disunification all involve multiple perceptual experiences at a time and multiple phenomenal contents. Such cases are highly abnormal. Where they occur, as, for example, with splitbrain patients, there are simultaneously experienced perceptual qualities entering into different phenomenal contents (each of which is a content experientially represented by the relevant subject at the given time).9 (44) Perhaps it will be replied that hallucinations and illusions are not highly abnormal; yet they sometimes involve disunified experiences. Recall Macbeth’s remark, “Is this a dagger I see before me, the handle towards my hand? Come, let me clutch thee. I see thee still, yet I feel thee not.” Macbeth’s visual experience represented to him a certain colored shape, which he identified as a bloody dagger. His tactual experience, when he went to touch it, informed him that nothing was there. Here, it may be said, there are two experiences, one tactual and one visual, that Macbeth underwent at the same time; for a single token experience cannot have an inconsistent content.
38
Chapter 1
Likewise, in the case of the straight stick in water that looks bent. Touching the stick, I feel it as straight. Touch and vision are thus at odds with one another.10 Again, there are two simultaneous experiences. And again, the subject’s perceptual experiences are disunified. (45) These cases, despite how they may seem initially, are not cases of phenomenal disunification. In the case of Macbeth, his experience by sight and touch was directed on a single region of space by his hand. This was part of the phenomenology of his experience overall even though what touch told him led him not to trust his sight. Similarly, as one looks at the stick in water and touches it with a hand, it certainly seems to one that the stick one is seeing is the same as the stick one is touching. This, it seems to me, is part of the phenomenology of one’s overall experience. To be sure, touch tells one something different about the shape of the stick than vision; and they can’t both be right. But why shouldn’t a single experience have an overall content that is internally inconsistent? Given the complexity of the processing that underlies the production of experience, it should not be surprising that in some cases a content of this sort is produced. There are plenty of examples of experiences with inconsistent contents. View the “impossible figure,” shown in figure 1.1. Here each set of steps is seen as ascending to the next, even though this is impossible. Another example is the so-called waterfall effect, which involves an illusion of movement (originally of a body of water). The most dramatic version of this is obtained by staring at a rotating spiral figure. While rotating, the spiral seems to expand. But after it is stopped, the spiral seems to contract, while also seeming not to get any smaller.
The Unity of Perceptual Experience at a Time
39
Figure 1.1 An “impossible figure.” Reprinted with permission from R. Gregory, Eye and Brain, London: Weidenfeld and Nicolson, p. 223 (1990).
(46) There remains a final objection I want to discuss to the one experience view. Consider the experience of a red square next to a green triangle. That experience, like all other perceptual experiences, has accuracy conditions. As such, it is a representation. And intuitively, that representation is complex; for anyone with the capacity to have an experience of this sort thereby has the capacity to have an experience of a green square next to a red triangle. The obvious explanation for this connection between capacities is that the two experiences are complex representations sharing the same representational parts. The experience of a red square next to a green triangle at time t thus has a component representation at t representing a red square and a
40
Chapter 1
component representation at t representing a green triangle. These representations, it may be insisted, have as much a right to be called “experiences” as does the overall representation of which they are parts. Indeed, it may be urged, on the theory developed in Tye (1995a) and (2000), it cannot be denied that the component representations are experiences. For, according to that theory, any perceptual state with a poised, abstract, nonconceptual representational content is a perceptual experience.11 And the content, “red square,” it may be insisted, is just as poised as the overarching content that includes it. Each content stands ready and available to make a direct difference with respect to what is believed, if attention is appropriately directed. Furthermore, what is true in this single modality case will be true mutatis mutandis in intermodal cases too. (47) Consider again the lump of clay that is a statue. Had that lump of clay been seamlessly embedded within a larger lump of clay that formed a cube, say, it would not have been a statue. The statue of the earlier example is constituted by a lump of clay that is maximal (that is, not contained within other, larger lumps of clay). The advocate of the one experience view can maintain that experiences are, in this way, like statues. Experiences are maximal PANIC states (states having a poised, abstract, nonconceptual content). So, even if some proper parts of experiences are representations, they are not themselves experiences. With this elucidation, the objection dissolves. (48) It is worth adding that it is not entirely clear anyway whether the experience of a red square next to a green triangle really does contain a part that represents a red square and a part that represents a green triangle. Clearly, the overall representation contains parts that would represent a red
The Unity of Perceptual Experience at a Time
41
square and a green triangle respectively, were they not contained within the overall representation, but it could be insisted that these parts are not themselves representations, given their actual situation. In the case of sentences, some parts, namely words, are surely representations. But it is not so clear that any parts of pictures are. For some representations, there is arguably a maximality constraint; for others not. (49) This completes my discussion of the unity of perceptual experience at a time. I turn next to the case of bodily experience.
2
The Body Image and the Unity of Bodily Experience
2.1 The Body Image (1) Try the following. Close your eyes. Stand up with your legs not touching one another. Hold your arms out away from your body and spread your fingers a little. You will find that you can still feel where your limbs are, from your legs to your head to your arms. You can feel your fingers. You can feel where their boundaries lie. As you move your arms around, you can feel the orientations of your arms relative to the Earth and their movements; and you can also feel the orientation of your torso (for example, whether it is tilted). Moreover, you can do all this without relying on touch. You have what might be called “general bodily feeling.” Since this feeling is always there, at least when you are awake, it is easy to ignore it, to focus your attention elsewhere. But it is of the greatest importance. (2) This feeling is sometimes called a “body image.” The image is constructed by the brain, and it provides each of us with an awareness of our own body locations and movements. People who have abnormal body images are sometimes in dire straits. Madame I, a patient of two French
44
Chapter 2
neurologists, G. Deny and P. Camus, at the beginning of the twentieth century, was a young woman who had lost her body image! She said this about her condition (as reported in Rosenfield 1992): I can no longer feel my arms, my legs, my head and my hair. I have to touch myself constantly to know how I am. I have the feeling my entire body is changed, even at times that it no longer exists. I don’t know how I lie in my bed. I am always looking for my body and my legs; and in the morning I ask myself what happened during the night. (p. 41)
Madame I did not know where her tongue was when her mouth was closed. She never felt hungry. She commented that “after drinking I don’t feel that I have had anything to drink” (p. 40). She was completely insensitive to pain, evincing no strong reaction to needles piercing her skin. Her sense of touch was normal, as was her sense of smell. But her sense of sight was somewhat impaired with respect to distance. (3) Madame I’s condition is not easy to imagine clearly. One way to try to think of what it must have been like for her— what it is like to lose general bodily feeling—is to think of instances in which one has been anaesthetized. Richard Gregory (1988) describes the effects on his body image of taking the anaesthetic Ketamine this way: At 4 minutes I could accurately describe how my legs were crossed, but had to think hard how to do so. I had a sinking feeling and felt that my middle had gone hollow, like plasticine. At 12 minutes, my Achilles tendon was squeezed, with a lot of force, to produce bruising, which lasted several days; but it didn’t hurt at all. So, although touch remained, pain was lost. . . . I felt almost as though as I was floating. At 14 minutes, I was asked to try to bite my tongue, but didn’t know where my mouth and tongue were, and was not able to do so (fortunately!). (p. 261)
The Body Image and the Unity of Bodily Experience
45
(4) In some cases, the body image is not lost, as it was for Madame I. Instead, it is either overextended or truncated. The former is what happens in phantom limb experiences: the subject has an experience of a body with boundaries beyond those that really exist, so that he or she has an experience of a body larger than it really is. The latter is what happens above for Gregory, with the shrinking of the image
46
Chapter 2
increasing through time. It is also what happens to some patients with spinal cord injuries. One such patient with a broken neck is reported (in Head 1920, p. 529) to have felt that he consisted of “a head and shoulders only”! Another commented, “My thighs disappeared!” The physician Oliver Sacks had an injury with similarly peculiar effects. He tells us that, after a bad fall on a mountain climb in Norway, he lost all feeling in one leg. He describes his condition as follows: When I closed my eyes, as a start, I had no feeling whatsoever of where the leg lay—no feeling that it was “here,” as opposed to “there,” no feeling that it was anywhere, no feeling at all. . . . . . . a total, absolute, existential breakdown immediately followed, and seemed precipitated by, the discovery of the breakdown of sensation and feeling, for it was then . . . that the leg . . . became a foreign, inconceivable thing, which I looked at, and touched without any sense whatever of recognition or relation. . . . In some sense, then, I had lost my leg. It had vanished; it had gone; it had been cut off at the top. I was now an amputee. And yet not an ordinary amputee. For the leg, objectively, externally, was still there; it had disappeared subjectively, internally. I was, therefore, so to speak, an “internal” amputee. Neurologically, neuropsychologically, this was the salient fact. I had lost the inner image, or representation, of the leg. There was a disturbance, an obliteration, of its representation in the brain—of this part of the “body-image,” as neurologists say. (1984, pp. 53–54)
(5) In having a general feeling of my body and the space it occupies, I have a general feeling of my head, my torso, my arms, my legs, and their boundaries. There is something it is like for me to have this feeling. In having the feeling at some given time t, I have a feeling at t of my head and I have a feeling at t of my torso and I have a feeling at t of my arms and further I have at t a feeling of my legs. I have also a
The Body Image and the Unity of Bodily Experience
47
feeling of any number of arbitrary parts of my body, for example, the lower half of my right leg, the top third of my left index finger. How is this to be explained? Either there is just one feeling here, a feeling of my whole body, which is also a feeling of my head, a feeling of my torso, a feeling of my arms, a feeling of my legs, and so on— either, that is, there is a single feeling with wider or narrower descriptions—or there is a feeling within which there are any number of other feelings. The latter supposition is not easy to understand, and it generates a problem of the unity of general bodily feeling, which the former supposition avoids. Consider, however, the following example, proposed as a model for the proposal that the feeling of the whole body contains within itself any number of other feelings of bodily parts. In my study at home I have a picture that reproduces a painting by Monet of an outdoor breakfast scene in a garden. The picture depicts, among other things, a child, some apples, a coffee pot, a half-eaten bun, a table, two ladies. Does this picture contain within itself a picture of a child, a picture of some apples, a picture of a coffee pot? Some would no doubt be inclined to say “yes,” but it is far from clear that this is the right thing to say. For where exactly are the boundaries of the putative picture of the child? Or are there many minimally different overlapping pictures of the child? If so, how many? And which one is the largest? Indeed, which is the smallest? Does the picture also contain indefinitely many pictures of arbitrary, undetached parts of things depicted in the picture of the breakfast scene? For example, does the picture hanging on wall contain a picture of the bottom 2/3 of a child’s arm, the bottom 3/5, the bottom 5/7? Intuitively, surely, the answer here is “no.” There are no more such pictorial parts of my picture than there is
48
Chapter 2
an undetached pot lurking inside the clay that constitutes the statue (in the example of chapter 1). The case of pictures, thus, cannot serve as a helpful model to illuminate the thesis that the feeling of the body as a whole contains, among other things, for example, a feeling of the left half of the torso. (6) Nor does introspection support this thesis. If you try to introspect the feeling of your left leg and its boundaries, you will fail. Introspection reveals to you only your leg, as represented in the feeling. When you introspect, you do not come across both your represented leg and a further inner particular, the token feeling representing the leg. You are aware of the boundaries of the leg, and thereby you are aware that you are having an experience of the leg and its boundaries. You are also, of course, aware that you are undergoing an experience with a certain phenomenal character. But you are not also aware of the token experience of the leg, any more than when you introspect the look of a scene, you are aware of a token visual experience in addition to the qualities represented by the experience as present in the scene. (7) My proposal, then, is that at any given time there is a single general bodily feeling in normal cases. This feeling is of the subject’s body, its limbs, bodily parts, and the regions of space these items occupy relative to some origin in the body (typically, the torso). (8) As is clear from (7), this feeling is not just a feeling of distinct bodily parts. It is a feeling of the entire body and its components. The feeling moreover is representational. And its content is typically torso-relative. For example, if I sit in a chair with my legs in front of me and I twist my torso to my left, my legs are now felt to be off to my right. If I stand up
The Body Image and the Unity of Bodily Experience
49
and then bend my torso so that it is parallel with the ground, while keeping my legs motionless, my feet feel closer. If I rotate my head forty-five degrees to the right while keeping my torso constant, my head feels turned to the right. If I lack a leg in the locations relative to the torso that I feel one, then my feeling is a misrepresentation. Going by my feeling alone, without collateral information, I am led to believe that I have a leg in certain locations when in reality I don’t. So, my feeling of where my body is, the space it occupies, may be inaccurate. It may extend beyond my actual body limits or it may fall short. (9) The experience of general bodily feeling is the key to the phenomenological unity of bodily feeling generally. This remark requires considerable unpacking.
2.2 A Theory of Bodily Sensations (10) As I sit at my computer, typing these words, I feel a slight ache in my right knee, an itch on my left arm, a soreness in a recently filled tooth, a dryness in my throat. Even though the aching I feel is not the same as the itching or the tooth soreness or the feeling of dryness in my throat, intuitively, there is a phenomenological unity. Just as the loudness of a sound is unified with the yellowishness of a simultaneously experienced flash, so too the soreness, dryness, aching and itching are unified in my bodily experience: I experience them all together. (11) In what does this unity consist? To answer this question, we need first a theory of pains, itches, tickles, and other such localized bodily experiences.
50
Chapter 2
(12) I shall begin with the case of pains. Intuitively, you cannot feel my pains and I cannot feel yours. Even if we are Siamese twins, joined at the hip and stung there by a bee, there are two pains, yours and mine. Maybe your pain is a bit different from mine. Without further information, that’s an open question, which it wouldn’t be, of course, if there were just one pain. Pains cannot exist without owners. There cannot be a pain with no one or no creature around to feel the pain. To be sure, there is the phenomenon of unnoticed pain, but even an unnoticed pain has an owner—the person who fails to notice it. (13) That pains are necessarily private and necessarily owned is part of our folk conception of pain and it requires explanation. The obvious explanation is that pain, in at least one sense of the term, is a feeling or an experience of a certain sort. That is certainly how scientists think of pain. Witness the definition of pain by the International Association for the Study of Pain, as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (in the journal Pain, 1986). And it is also part of our commonsense conception. Since you cannot feel my feelings any more than you can laugh my laughs or scream my screams, and since there cannot be a feeling without a subject for the feeling any more than there can be a laugh without a laugher or a scream without a screamer, pains, conceived of as feelings, are necessarily private and necessarily owned. (14) The uncontroversial proposal that pain is a feeling encounters difficulty, however, when we note that we locate pains in bodily parts. We say things like “I have a dull pain
The Body Image and the Unity of Bodily Experience
51
in my right leg,” and we use descriptions for pain that appeal to bodily parts, for example, “the burning pain in my stomach.” The feeling of pain isn’t in my right leg or my stomach, but the pain, it seems, is. (15) One strategy for handling this difficulty is to claim that when I feel a pain in my chest, say, the pain really is in my chest even if the feeling of pain is not. The pain itself is spatially located in its felt location within the body, the feeling of pain is not. That, however, can’t be right. Pains, whatever else they are on such a proposal, are mental entities, mental objects for feelings of pain. And mental objects cannot exist in chests or legs any more than such objects can exist in walls or tables. Of course, I can feel a pain in a hand (that has recently been amputated) and I can place the stump of my arm against a wall or a table. But the pain I feel isn’t in the wall or table! Furthermore, once pain and the feeling of pain are split apart, there is now no explanation for the necessary privacy and necessary ownership of pains. (16) A second response is to say that the word ‘in’ in such contexts has a special causal sense. Pain and the feeling of pain are one. In conceiving of a pain as being in a leg, we are conceiving of it as being caused by damage to the leg, not as being spatially inside the leg. That again seems very implausible. For one thing, it is ad hoc. For another, unless it can be shown to be the only alternative that works, it unnecessarily multiplies word senses. Why insist that ‘in’ here means something different than what it means when it is used elsewhere? Those who take this view try to motivate the proposal by noting that inferences like the following are invalid: (1) I feel a pain in my fingertip; (2) The fingertip is in my mouth;
52
Chapter 2
therefore, (3) I feel a pain in my mouth. How could this be, they ask, if the word ‘in’ is used in (1) and (3) in its ordinary spatial sense ( Jackson 1977; Block 1983)? After all, if A is spatially inside B and B is spatially inside C, A must be spatially inside C. This line of argument would provide some support for the causal proposal, if there were no other explanation consistent with the claim that ‘in’ in such contexts has its ordinary spatial sense. However, there is such an explanation. (17) The explanation is that ‘in’ in (1) and (3) is occurring in a representational context. Let us assume initially that (1) can be read so as not to require for its truth that I have any hands, as, for example, in a case of a phantom arm pain. What (1) asserts, I suggest, is that the experience of pain represents something as being in my fingertip. What is represented as being so located is left open by the statement, but the empirical evidence supports the view that it is tissue damage. Since the experience of pain does not represent anything about the mouth or the spatial location of the finger relative to the mouth, (3) does not follow from (1) and (2). (18) One might object that even if the representational approach explains the inference failure from (1) and (2) to (3), on the proposed reading of (1), it does not explain the corresponding failure from (4) The pain is in my fingertip and (2) to (5) The pain is in my mouth,
The Body Image and the Unity of Bodily Experience
53
if (4) and (5) are read as requiring for their truth that the relevant bodily parts exist.1 For the pain experience adverted to by (4) is now a de re representation with respect to my fingertip. Likewise, the pain experience for (5) is de re with respect to my mouth. (19) By way of reply, we should note that there is more than one ordinary spatial sense of ‘in’. Where there is a hollow physical object, O, the claim that something X is in O can be understood either to assert that X is within the cavity bounded by O or to assert that X is (at least partially) embedded within a portion of the cavity-surround (the top, bottom, and sides of O). For example, (6) Tanya has a ring in her nose uses the second sense of ‘in’, whereas (7) My car is in the garage uses the first. (20) The explanation for the inference failure from (4) and (2) to (5) now goes as follows. (4) is true if and only if my fingertip is such that my pain experience represents tissue damage (let us suppose) spatially within it.2 (2) is true if and only if my fingertip is spatially within the cavity bounded by my mouth. (5) is true if and only if my mouth is such that my pain experience represents tissue damage embedded within a part of its roof, walls, or base. Patently (5) now does not follow from (4) and (2). (21) Perhaps it will be replied that once different spatial senses of ‘in’ are admitted, that is all that is needed to explain the inference failure in the last case. The appeal to representation is otiose. This misses the point. The
54
Chapter 2
pain/experience of pain is not in my mouth in either spatial sense. To offer an explanation that supposes that it is is to offer an explanation based on false assumptions. And that is to offer no explanation at all. (22) It should be clear from my remarks above that the phenomenon of phantom limb pain receives a straightforward and intuitive explanation, if pains have representational content. A pain in a leg represents that something—tissue damage, let us suppose again—is going on in a leg.3 That no more requires that there actually be a leg than thinking of a golden mountain requires that there be such a mountain. In phantom limb pain, the relevant bodily part is hallucinated. The case is thus one of experiential misrepresentation, as is the case of hallucinatory visual experiences. (23) A similar account may be given of referred pains. One can feel a pain in the left arm when there is nothing wrong with the arm, the cause of the experience being a disturbance in the heart. Such a pain intuitively is inaccurate or misleading; for without additional information, on the basis of the pain, one would be disposed to nurse the arm, to rub it, to believe that something is awry in the arm itself. The obvious explanation again is that there is experiential misrepresentation. Here the bodily part exists, but the case is one in which the subject is under an illusion. Her experience represents (in part) that there is tissue damage at a certain bodily location, when in reality the damage is elsewhere in the body. (24) In my view, then, we have above some very strong reasons for supposing that pains are experiences that have representational content. (25) Now suppose you have a throbbing pain in your finger. You can certainly have a pain without noticing it, as, for
The Body Image and the Unity of Bodily Experience
55
example, when you are distracted for a moment by something else, but if you do notice a pain—if you are introspectively aware of it—then your attention goes to wherever you feel the pain (in this case, to your finger). Your attention does not go to where your experience is (that is, to your head, if your experience is a physical thing) or to nowhere at all. In attending to your pain, you are directly and immediately aware of certain qualities, which you experience as being localized in your finger. Those qualities are experienced by you as awful. They are qualities you want so strongly to stop experiencing. The same is true even if you are feeling a pain in a phantom finger. Still, you are directly aware of qualities you strongly dislike, qualities that you experience as deeply unpleasant and as being in a finger, even though the finger no longer exists. The first point to stress, then, is that the qualities to which we attend in introspecting pain experiences are not qualities of the experiences (assuming that there is no massive error), but qualities of bodily disturbances4 in regions where the pains are felt to be, if they are qualities of anything at all. (26) Thus, if we try to focus our attention on the token pain experiences themselves, when we introspect, we fail. Our attention automatically and necessarily goes to the represented bodily disturbances and their experienced qualities. In this way, our pain experiences, like our perceptual experiences, are transparent to us. (27) It is generally agreed that pain has distinct sensory and affective/emotional components, subserved by different neural mechanisms. This view of pain was first proposed by Melzack and Casey in 1968, and in the thirty years since then it has been shown to be well motivated by both a wealth of clinical data and neuroscientific evidence.5
56
Chapter 2
Normally, in a pain experience, both components are present. But in some cases, the affective component is missing. For example, people who undergo prefrontal leukotomies (operations that sever the neural connections in the deep white matter in the frontal lobes) as a last resort for their intractable, constant, severe pain are typically cheerful and relaxed afterwards. They report still having pains, but they no longer mind them. Similar reports come from people suffering pain who are under hypnotic suggestion or nitrous oxide. Such cases of “reactive disassociation,” as Dennett (1978) calls them, are ones in which the distinctive sensory dimension of pain is present but the aversive component is gone. Is pain itself still present? It seems so. The patients say that they continue to feel pain. I see no reason not to take these reports at face value. What they show, I suggest, is that pain is not essentially an aversive experience. (28) Pain is essentially a sensory experience, however. Whatever else pain is, at its core, it is a bodily sensation. Take away the characteristic sensory component, and no pain remains. Certain abnormal unpleasant experiences, for example, dysaethesia, lack any sensory component, and they are not classified by their subjects as pains. Other unpleasant experiences, for example, an irritating itch, are sensory, but they aren’t pains since the distinctive sensory content of pain is missing.6 (29) In any event, a typical pain experience has both a sensory and an affective dimension. Consider first the sensory side of pain. The normal cause of pain, qua sensory experience, is tissue damage. The obvious hypothesis, then, is that the quality paradigmatically represented by pain experiences qua sensory experiences just is tissue damage. Pains
The Body Image and the Unity of Bodily Experience
57
typically differ with respect to the species of tissue damage represented. As I noted in my (1995), a twinge of pain represents a mild, brief case of damage. A throbbing pain represents a rapidly pulsing disorder. Aches represent regions of damage inside the body rather than on the surface. These regions are represented as having volume, as gradually beginning and ending, as increasing in severity, as slowly fading away.7 The volumes so represented are not represented as precise or sharply bounded. This is why aches are not felt to have precise locations, unlike pricking pains, for example. A stabbing pain is one that represents sudden damage over a particular well-defined bodily region. This region is represented as having volume (rather than being two-dimensional), as being the shape of something sharpedged and pointed (like that of a dagger).8 In the case of a pricking pain, the relevant damage is represented as having a sudden beginning and ending on the surface or just below, and as covering a very tiny area. A racking pain is one that represents that the damage involves the stretching of internal body parts (e.g., muscles). (30) Consider next the affective dimension of pain. Pain is normally very unpleasant. People in pain try to get rid of it or to diminish it. Why? The answer surely is because pain feels unpleasant or bad, because it is experienced as such. But what exactly is experienced as unpleasant? The pain itself, I have argued, is an experience. One’s attention, when one feels pain, goes to a place different from the one in which the experience of pain is located. The qualities that are experienced as unpleasant are located in the place to which one attends (in normal circumstances). People whose pains lack the affective dimension undergo purely sensory representations of tissue damage of one sort or another in a localized
58
Chapter 2
bodily region. Those whose pains are normal experience the same qualities, but now those qualities are experienced by them as unpleasant. It is precisely because the qualities are experienced as unpleasant or bad that people have the cognitive reactions to them they do, reactions such as desiring to stop the pain. (31) To experience tissue damage as bad is to undergo an experience that represents that damage as bad. Accordingly, the affective dimension of pain is as much a part of the representational content of pain as the sensory dimension is. (32) The representational content of pain, in my view, is nonconceptual. Admittedly, my talk above of the unpleasantness of pain, of its experienced badness, may sound cognitive. But I do not intend it to be understood in this way. It seems to me that the most plausible view here is that we are hard-wired to experience pain as bad for us from an extremely early age. (33) Consider the other side of the coin for a moment. A child as young as two months, upon tasting a little chocolate, typically behaves in a way that signifies that he or she wants more. The child will open and close its lips, push forward toward the chocolate, look happy. Why? The answer is that the chocolate tastes good. That’s why the child wants more. The child’s gustatory experience represents a certain taste, and the child experiences that taste as good. The taste is experienced as good by the child in that the child undergoes an overall experience that represents the presence of the taste in the mouth and represents it as good. (34) Intuitively, this is not a cognitive experience. It does not require concepts. It is preconceptual. For another example, consider orgasm. Orgasm is a bodily sensation, but it is
The Body Image and the Unity of Bodily Experience
59
not only that. The most natural description of an orgasm, and indeed of any pleasant sensation, is “It feels good.” One’s orgasm represents a certain change in the region of the genitals as good for one, as something apt to benefit, not to harm one.9 That isn’t a conceptual response. One cannot help but feel the relevant bodily disturbance except as good. One is hard-wired by nature to experience it in this way. It is not difficult to fathom why. (35) Pain is the opposite, as is the experience of smelling vomit, for example. In the latter case, one experiences a certain smell as bad, as something apt to harm. That’s part of the representational content of the experience. In the former case, it is tissue damage within one’s own body one experiences as bad, as apt to harm. (36) It is not just the affective dimension of pain that does not require concepts. Intuitively, one does not need concepts to have a pain, period. Given the right stimulus, one feels pain, whatever concepts one has in one’s repertoire. This is not to say that one’s cognitive assessment of a situation can never influence or affect one’s experience of pain. Obviously, it can. The point is simply that the basic experience of pain requires no cognitive sophistication. Humans are hard-wired to experience pain when they undergo tissue damage, whatever they think or believe. (37) On the account I have been developing, then, pains are experiences having a complex, nonconceptual representational content. But intuitively, it must be admitted they are not only this. Intuitively, if I feel a pain in a leg, and I attend to what I am feeling, I attend to a quality that seems to be tokened in my leg, a quality that I strongly dislike and that, in one ordinary sense of the term ‘pain’, is surely pain.
60
Chapter 2
A theory that denies this categorically is at odds with what we ordinarily believe. How can my proposal accommodate this claim? The answer, I suggest, is to acknowledge that pain is not only a certain sort of experience but also a certain quality or type (tissue damage) insofar as that quality or type is experientially represented. (38) On this proposal, if I feel a pain in a leg, I undergo an experience that represents that there is tissue damage in a leg and further represents that damage as bad. My feeling or experience is itself a pain. But the tissue damage represented by my experience is also pain, given that it is so represented;10 and this is the case, whether or not any real token tissue damage exists in my leg or indeed whether I have a leg. (39) The same sort of position may be developed for other bodily experiences. The term ‘tickle’, in one common usage, applies to a certain sort of feeling. To have a tickle is to undergo an experience that represents (in part) the presence of something lightly touching or brushing against the surface of the body. Tickles, in this sense, are essentially sensory representations of bodily disturbances, just as pains are. Tickles also have a standard affective component. They are felt as pleasing at least initially, though as they continue they may be felt as very unpleasant. The quality of tickling is not just a certain sort of experience, however. Tickling, like pain, is also an experientially represented type (so long as the type is present in the content of experience)—in this case, a type whose tokens are instantiated at the surfaces of bodies. Itches are experiences that represent surface disturbances, though not ones of the same sort as tickles. In addition, itches are felt as unpleasant, and this is part of their content too—the part that causes in their owners cognitive reactions
The Body Image and the Unity of Bodily Experience
61
of wanting the experience to cease (less intensely than for pains) plus the impulse to rub or scratch the relevant bodily part.11 Further, the quality of itching is an experientially represented quality just as the quality of tickling is. Tingling sensations represent patterns of bodily disturbance that consist of a large number of tiny distinct parts, each of which is quickly varying or pulsating. The feeling of thirst represents dryness in the throat and mouth. Feeling hot is a state that represents an increase in body temperature above the normal one. Hunger pangs represent contractions of the stomach walls when the stomach is empty.12 In each of these cases, there is also an affective representational component. And in each of these cases, the representations are not conceptual states. So, the fact that for some bodily experiences, for example, the feeling of hunger, the person in the street may not be able to say just which bodily state is represented has no significance. (40) Tingling experiences, itches, and tickles are commonly felt in phantom limbs just as pains are. And the explanation is the same. The experiences are representing bodily disturbances in regions of the body that no longer exist. (41) Occasionally, bodily experiences are felt in manipulated tools (e.g., a scalpel) or, in one instance, between two fingers (Bekesy 1967, pp. 220–226). In these cases, however, the experiences are still felt within the subject’s body, for the body here feels extended along the tool or between the fingers. Amazingly, it is even possible to feel sensations along the surface of someone else’s nose! If you want to do this yourself, you’ll need two helpers. V. S. Ramachandran provides instructions as follows: Sit in a chair and ask Julia (the first helper) to sit on another chair in front of you, facing the same direction as you are. Have Mina (the
62
Chapter 2
second helper) stand on your right side and give her the following instructions: “Take my right hand and guide my index finger to Julia’s nose. Move my hand in a rhythmic manner so that my index finger repeatedly strokes and taps her nose in a random sequence like a Morse code. At the same time, use your left hand to stroke my nose with the same rhythm and timing. The stroking and tapping of my nose and Julia’s nose should be in perfect harmony.”
Ramachandran continues: After thirty or forty seconds, if you are lucky, you will develop the uncanny illusion that you are touching your nose out there or that your nose has been dislocated and stretched out about three feet in front of your face. The more random and unpredictable the stroking sequence, the more striking the illusion will be. (Ramachandran and Blakeslee 1998, p. 59)13
In other experiments described by Ramachandran, subjects feel sensations in a dummy rubber hand, lying on a table in front of them, and even in the table itself! In all of these cases, the subjects feel their own bodies to have changed shape, to have stretched or distorted to include external objects. What perhaps is most surprising is the malleability indicated by these experiments of the body image. In the first experiment, even though you know that you have the same nose as always, your body image is made to shift quite dramatically given less than one minute of the right kind of sensory stimulation. 2.3 The Problem of Bodily Unity (42) We are now ready to return to the question of unity. Recall that Madame I, the woman who had lost her body image, was insensitive to pain. Think also of the case in which you wake up in the morning, having lain awkwardly on an arm, cutting off the blood flow there. Lacking any
The Body Image and the Unity of Bodily Experience
63
bodily feeling in that arm, you would be unable to experience pain in the arm. One cannot feel a pain without feeling the pain in a particular bodily region.14 The region may not be precisely delimited, but nonetheless, each pain is felt essentially as localized in a part of the body of the owner. Where there is no general bodily feeling in a given body region, it is not possible to feel pain there. What is true here for pains is true for itches, tickles, and other such bodily experiences. It is thus a phenomenological requirement for feeling a pain that one feel the bodily region in which the pain seems to be. Again, this is not to suppose that the relevant bodily region actually exists. The point is that feeling a pain requires feeling a location that is itself felt as a location within a body part, whether or not there really is such a part. This feeling of the given bodily region is not a discrete feeling distinct from the feeling of another bodily region. I argued earlier that there is just one general bodily feeling, a feeling that represents the whole body space and bodily parts occupying that space. Feeling a pain in one’s left leg, say, necessitates that one have a general bodily feeling that, in part, represents the left leg. Likewise, feeling an itch in one’s right arm necessitates that one have a general bodily feeling that, in part, represents the right arm. (43) It will not do to try to explain the phenomenological unity of my pains and itches, for example, by saying that they are projected onto the same background body feeling or image. Pains and itches are not projected in this way at all. I thus oppose the following remarks by Barry Maund (2002): [T]he pain one feels in one’s leg is a subjective feeling that one “projects” onto the leg. It is not a real projection. One has a body
64
Chapter 2
image which represents the body. The pain is projected onto, is located on, that part of the body image which represents the leg. Likewise with colors. There is a subjective quality which one “projects” onto an external object, say to the moon, to represent it as yellow.
This seems to me completely wrong. If I see the moon, I am not aware of a subjective visual field that represents the moon. I am aware of the moon and perhaps some stars located in distant regions of space before my eyes. Likewise, if I have a pain in my leg, I am not aware of an image that represents my leg. I’m aware of my leg and its condition. To suppose that it is the representation itself—the subjective visual field or the body image—of which I am really aware in these cases is like supposing that if I desire eternal life, what I really desire is the idea of eternal life. That, however, is not what I desire. The idea of eternal life I already have. What I desire is the real thing. And it does not help, of course, to say that it must be the representation of which I am aware, since the case might be one of hallucination—no moon or no leg—for patently, if there is no eternal life, it still isn’t the idea of such a life that I really desire. If the pain is a phantom one or the visual experience totally delusive, as noted earlier, I simply undergo an experience that represents something that isn’t there. (44) Nor will it do to say that the unity of my pain and my itch is achieved simply by the simultaneous presence of the experience of general bodily feeling. For the unity is experienced, and a conjunction of experiences is not an experience. It seems, then, that there must be a further overarching experience that subsumes the three experiences—an experience of the pain, the itch, and the body unified together. But this experience requires that there be an experience of the
The Body Image and the Unity of Bodily Experience
65
unifying relation, else there can be no experience of the three experiences as unified. So, now we have four component experiences. And as in chapter 1, a regress has begun to which there is no end.15 (45) In chapter 1, I took the view that in everyday perceptual consciousness, at any given time, there is a single experience with a rich, multimodal content. My proposal now is that in bodily experience, there is just a single experience too at any given time. In the case above, this experience is an experience of the body with pain in the left leg and itching in the right arm. Under a less encompassing description, it is an experience of the body. It is also an experience of a pain in a leg. And it is an experience of an itch in an arm. There is one experience here that can be described in very different ways. That experience represents the body space, its boundaries, the body parts, their movements, their orientations relative to one another and to the Earth, and the disturbances that are occurring in discrete regions of the body, both internally and on its surfaces. (46) Counterparts to many of the obvious objections to a view of this sort have already been discussed in chapter 1, so I shall not repeat my replies here. There is, however, one new objection I want to take up, namely that, on the proposal I am making, if there is but a single rich bodily experience at a time, then, in the case above, it follows that the pain in my left leg is one and the same as the itch in my right arm. And that surely is absurd. (47) It is certainly true that on my proposal, in the above case, the token experience of a pain in my left leg is one and the same as the token experience of an itch in my right arm. There is one experience here that represents both tissue
66
Chapter 2
damage in my left leg and a surface disturbance of a certain sort in my right arm. But pain (or painfulness) is experienced in one place and the quality of itching in another. These qualities are different qualities, represented by my experience as being tokened in different parts of my body. So, there is no mistaken identification of pain and itching and certainly no absurd consequence that in attending to pain, I am attending to itching or vice versa. (48) My response, then, to the question of what unifies different simultaneous bodily experiences is that it is a pseudoquestion, based on a mistaken assumption. There is only a single bodily experience at a time, an experience with a very rich and complex bodily phenomenal content. Qualities that are experienced in undergoing bodily experience—qualities that are not qualities of experiences but rather qualities of bodily disturbances, if they are qualities of anything—are experienced together at a time by entering into this shared content. In this way, the painfulness of a pain, the itchiness of an itch, the ticklishness of a tickle are phenomenologically unified. And, as with the case of perceptual experience, unity goes with the closure of experience under conjunction. (50) We have now an explanation of both the unity of perceptual experience at a time and the unity of bodily experience at a time. The question of their combined unity and that of conscious thoughts and moods is the focus of chapter 3.
3
The Unity of Perceptual and Bodily Experiences, Occurrent Thoughts, and Moods
3.1 Opening Remarks (1) So far, I have discussed the unity of perceptual experience and the unity of bodily experience at a time. But I have not addressed their common unity. The experienced qualities of smells, sounds, tastes, and so on are not unified in isolation from what is felt in the body. If, for example, I feel a pain in a finger I am examining, pain is experienced together with the qualities I experience perceptually. The finger is presented to me visually and tactually while I feel pain in it; and all these elements are unified or connected in my consciousness. (2) There is unity too with occurrent thoughts and moods. The pain in my finger is one that has been there for some time. It is not responding to treatment. As I examine it, I feel mildly depressed. I think to myself that I can’t type with that finger, that I have writing I must get done in the next few days, and that I am already way behind. I begin to worry. The pain intensifies. I rub my finger harder. The train of thinking I undergo here is a conscious one. It involves several occurrent thoughts, the qualities of which
68
Chapter 3
are unified with the experienced qualities of the depression I feel and the pain I experience. (3) I argued in chapter 1 that in normal, everyday cases, people do not undergo five different simultaneous perceptual experiences as they use all five senses. Rather they undergo a single perceptual experience at a given time, an experience with a visual, auditory, olfactory, gustatory, and tactual phenomenology. In chapter 2, I took a corresponding view for bodily experience. What should we say about perceptual-bodily unity? That is the topic of section 3.2 of this chapter. Section 3.3 addresses the unity of experiences with conscious thoughts. Section 3.4 focuses on moods. 3.2 Perceptual Consciousness and Experience of the Body (4) In the last chapter, I argued that bodily experience is an experience that represents the body space and boundaries, along with various internal bodily disturbances. The experience of the body is also part and parcel of normal, everyday perceptual consciousness. For we experience things in relation to our bodies. And this involves experience of our bodies. In the case of touch and taste, this is obvious. We taste things with our tongues, and the experience of them involves contact with our tongues and mouths, which is itself part of the phenomenology. Likewise, we touch things with our hands and we experience the contact with the things touched. One who lacks any feeling in her mouth, tongue, and fingers cannot experience the soft, smoothness of a velvet tunic against her fingers or the taste of gin as it runs over her tongue and down her throat.
The Unity of Perceptual and Bodily Experiences
69
(5) This is not to imply that an abnormal subject without any feeling in her fingers could not acquire the knowledge by touch that her fingers are touching the velvet or that the velvet is smooth. Still, such a subject lacking any feeling of where her fingers are would not experience the contact between her fingers and the velvet. Thus, her awareness by touch would be very different from ours. Recall the case of Madame I in chapter 2, the woman who had lost her body image. She reported that she could not feel arms, leg, head, and hair, adding “I have to touch myself constantly to know how I am” (Rosenfield 1992, p. 39). Touch informed Madame I of where her body was, but she could not feel the location of her body, and so she could not feel the contact between her fingers, as she ran them across her body, and the part of her body she was touching. (6) I also do not mean to suggest that real fingers are necessary in order for a person to have the experience of touching something with her fingers. If my right hand has been amputated, I may still feel fingers there, and if I do, I may undergo an experience that represents the presence of a surface in contact with my fingers. What is crucial to the experience of contact is that the part be represented in the person’s body image. (7) Smells and sounds are experienced as occupying spatial locations and coming from directions. The loud noise of the firecracker is experienced as being on the left; the fragrant smell of the flower is experienced as being where the flower is, a little to the right, say. The directions left and right here are set by the body of the perceiver. Interestingly, it is the torso that seems to be most important. A noise from behind on the left is normally experienced in that location even if one’s head is rotated backward to the left, while keeping the
70
Chapter 3
torso motionless, so that the sound is in front of the rotated ear. Similarly a smell from the right side in front is still experienced as being on the right, if one turns one’s head so that one’s nose is aligned with the smell. (8) I am not claiming that an experience of the body is required in every case for an experience of a sound in a given direction. What an experience of the latter type requires is an experience of here; a sound to the left, for example, just is a sound to the left of here. In the normal case, the experience of here is the experience of a certain bodily location that is the origin for up/down, back/front, and left/right axes whose directions are set by the torso. But arguably, one could still undergo auditory experiences as coming from definite directions even if one’s body was completely anaesthetized. I shall return to this point shortly. (9) Consider vision. Tilt your head from left to right, as you sit viewing a painting on a wall, while keeping your body upright. The painting does not seem to tilt with the head. The bottom of the painting still appears horizontal, and the sides upright.1 Nor does the painting seem to tilt if you keep your head position fixed relative to the torso, while tilting the torso forty-five degrees to the right.2 Now rotate your torso forty-five degrees to the right and rotate your head back to its original position so that the painting is level with the eyes. The painting will be experienced as being off to the side from the direction of straight ahead. (10) In experiencing things visually, we experience their orientations and directions, and these are set in part by our own bodies. We use our own bodies to assign orientations and directions to things, as manifested in the visual phenomenology. The spatial properties of being horizontal and
The Unity of Perceptual and Bodily Experiences
71
being upright, for example, are relative to a set of axes, positioned at the viewer. Intuitively, these axes have their origin centered between the viewer’s eyes. Their directions, however, are not up/down, left/right, back/front with respect to the head; if they were, the painting would appear to shift its orientation as the head is moved.3 Instead the axes have their back/front and left/right directions set relative to the torso in the usual way, with the up/down direction usually set via the directional pull of gravity on the torso. (11) Again, I am not supposing that experience of the body is required for visual experience. The point is that in experiencing the direction or orientation of something, we experience it as being in a certain direction or at a certain orientation relative to a certain viewpoint. That viewpoint is one we experience ourselves as occupying; and in normal vision, we experience that viewpoint as being within our bodies—intuitively, somewhere in the middle of our heads behind the eyes. Even so, the torso, not the head, is the most important bodily factor in fixing how the directions of the axes are for that viewpoint. (12) That the relevant viewpoint is in the head behind the eyes is well illustrated by the following story adapted from Dennett (1978). Suppose that neurosurgery has developed to the point at which it is possible to remove brains from bodies, while replacing the severed nerves with two-way radio connections that allow the brains and bodies to communicate just as they did before. The connections are established via tiny radio transceivers attached to the severed nerve endings. One morning I awaken, knowing that this operation was performed on me last night, and I feel just as I did before. Upon looking in a mirror, I see the same face I always did and, looking down, my body appears just the
72
Chapter 3
same. I then ask to see my brain and I am taken to a vat, full of fluid, in which my brain is floating, surrounded by electronic gadgetry. As I view the brain, I think to myself, “Here I am, looking at my own brain. The world is certainly a weird and wonderful place.” I am a physicalist, however. And I believe that my experiences take place in my brain. Why, then, didn’t I think, “Here I am, in a vat of fluid, being stared at by my own eyes”? (13) The answer surely is that my visual experience of the world is an experience of things in relation to a certain viewpoint, and that viewpoint is one I locate behind where I feel my eyes to be within where I feel my head. My experience in the above case is of my brain in front of me; it is not an experience of my own eyes straight ahead, turned in my direction— as would be the case if I were normally embodied but my eyes had been removed and rotated toward my body while keeping their connections to my head intact (by applying a special chemical stretching agent to those connections, say). I naturally think that my brain is in front of me because I naturally and normally locate my viewpoint behind where my eyes feel to be within my head (quite correctly until this morning). Still, why is it that my thought that I am here, looking at my own brain, persists even after my physicalist reflections should lead me to locate myself where my brain is? The explanation, I suggest, is that my thought, like all conscious thoughts, comes wrapped in an auditory linguistic image. It is for me as if I am speaking words internally in my natural language in my characteristic pattern of stress and intonation. In consciously thinking, thus, I undergo an associated auditory experience and the sounds represented by that experience are experienced as sounds made by me and
The Unity of Perceptual and Bodily Experiences
73
further as sounds I am making within where my head is experienced to be. Accordingly, the phenomenology of my conscious thoughts places me outside my brain, behind my eyes; and that is what makes it so hard for me to think that I am really where my brain is, rather than being in front of it. (14) My claim that experience of the body is not required for visual experience or for auditory experience is supported by the case of Madame I. She seems to have had
74
Chapter 3
roughly normal vision, with some reduction in visual acuity for distance, and normal hearing, but she had no body image. Consider also the following imaginary case.4 Suppose that while you are sleeping one night, a complex and fiendish operation is performed by mad scientists in which your brain is removed from your body, and then, after brain removal, your head is severed and the rest of your body destroyed. The severed head is supplied artificially with blood from a machine and its auditory and visual receptors have radio transceivers attached to them. Radio transceivers are also attached to the auditory and visual nerve endings dangling from the disembodied brain. The transceivers connected to your head are tuned so that they will receive radio messages from the corresponding transceivers attached to your brain, as soon as a switch is flipped. Your head is now placed on a chair, right side up, in front of a TV set with your favorite episode of Monty Python playing. The switch is flipped. Would you suddenly go from experiencing nothing to having visual and auditory experiences of Monty Python? Would you hear the words, “And now for something completely different,” as John Cleese speaks them? Would you see and hear Michael Palin, as he performs the Lumberjack Song? It seems to me that you would. All the relevant information is getting passed from your eyes and ears to your brain; the same neural regions in the visual and auditory cortexes are being activated in just the way they would have been activated, had you been sitting and watching Monty Python in the usual way. But you would have no experience of your body; for your body other than your head has been destroyed and the only links between your brain and your head are the auditory/visual ones. Admittedly, you might go mad pretty quickly, or you might develop a strong
The Unity of Perceptual and Bodily Experiences
75
aversion to Monty Python. But the case, though fantastic, is surely coherent. And its coherence shows that it is possible for a subject to undergo auditory and visual experiences while having no bodily experience whatsoever. (15) At the current time, sitting on a patio by a swimming pool with my computer while sipping some tea, I have a single perceptual experience with a rich and multimodal phenomenology. My experience represents to me visual, auditory, olfactory, gustatory, and tactual features in relation to myself. I experience the red flowers to the left of here, the diamond shape of the tiles on the patio relative to me and my viewing position, the sounds of a bird straight ahead, the smell of the chlorine from the pool off to my right, the smoothness of the computer keys against my fingers, the taste of the tea as it comes into contact with my tongue. The world, as I perceptually experience it, thus, is a world in relationship to here. And here, in the normal case, is where my body or certain parts of my body feel to be.
76
Chapter 3
At the current time, I also feel an itch from a mosquito bite on my ankle and a pain in my left knee from too much running. The pain is unified with the itch and they are both experienced together with the various things I experience perceptually. This is so, I now want to suggest, because I am undergoing but one experience at the current time, an experience of a perceptual-bodily sort. There is indeed a single perceptual experience; and there is a single bodily experience. But there is just one experience here, described in two different ways. This experience represents the sounds, smells, tastes, surfaces, and so on in the world around me in relation to my body, its parts and their boundaries, together with various bodily disturbances. My current experience is closed under conjunction across the board.5 And with such closure goes perceptual-bodily unity. (16) Without an experience of the body, there can be no experience of pain, no itches, no tickles. But perceptual experience can still remain; for, as we have seen, such experience can occur in the absence of bodily feeling. Even so, without the experience of the body, there is certainly no question of uniting bodily and perceptual experience and thus no problem to be considered concerning their unity. (17) Can there be cases in which both perceptual and bodily experience are present, but there is perceptual-bodily disunity? Here is one possible, imaginary candidate. Suppose that while you are sleeping one night you are given a drug to prevent you from waking and your eyes and your ears are removed from your head, while keeping their neural connections intact. This is accomplished via the application of a special neuron-stretching chemical agent that is applied to the relevant neurons as the eyes and ears are detached from your head. An anesthetic is injected into your head so
The Unity of Perceptual and Bodily Experiences
77
that when you awaken you will have little or no bodily feeling in the head except for the mouth region. Next, your nose is sealed, and a mouthpiece, which is attached to an oxygen supply, is placed in your mouth. You are then placed, lying in a horizontal position, inside a large chamber of sand, with the exception of your eyes and ears, which are positioned above the sand in roughly their usual relative positions so that they can detect the sights and sounds you would have been able to detect had you been above the sand in your usual embodiment. The sand in which you are buried is within an IMAX movie theater. There is no one else around. When you come to, you experience just the sights and sounds you would experience were you on a wild roller-coaster ride; for that is what is presented to you via the screen and the sound system in the theater. As far as your audiovisual experience goes, it is for you as if you are on a roller coaster. But that is not how it seems to you, as far as your bodily and tactual experiences are concerned. You feel the mouthpiece in your mouth, your body lying in the horizontal position, your rthyhmic but labored breathing, the pressure of the sand on your chest and legs—a pressure that keeps you motionless with the exception of your fingers as you straighten and close them in the sand. You have the bodily and tactual experiences of someone buried alive! On the one hand, then, it seems to you that you are moving fast through space, up and down, round and round. On the other, it seems to you that you are trapped, motionless, underground. Is not this a case of perceptual-bodily disunity? It seems to me unclear. To be sure, your overall experience is likely to seem incredible to you. Your auditory and visual experiences are completely at odds with the ones provided
78
Chapter 3
you by your sense of touch and the associated bodily sensations. With your introspective attention directed one way, you are aware that you are having an experience as of yourself on a roller coaster. With your attention directed differently, you are aware that you are having experiences that go with lying horizontally, surrounded by sand or loose dirt. It is, then, as if you are in two radically different worlds.6 Even so, it seems to me, one reaction you may well have to your situation is that of asking yourself: How could I be experiencing both these things? How could I possibly be experiencing these things together? And this presupposes, of course, that there is unity or experienced togetherness, even though its existence seems incoherent to you. Moreover, it may be that you can attend to both of your experienced situations all in one glance, as it were. Obviously, you will find your situation as you do so unintelligible, at least until you are able to reason out what must have happened. But this does not establish disunity. For, as we saw in chapter 1, some experiences within a single sense modality have inconsistent or impossible contents. (18) For clear cases of perceptual-bodily disunity, we must turn, I believe, to actual or possible split-brain scenarios. These are discussed further in chapter 5. 3.3 Unity and Conscious Thoughts (19) As I took the ferry trip last summer from Athens to the island of Hydra, approaching the Hydra harbor, I consciously thought to myself: Oh lucky man, am I. The sky was blue, the water glistened, the sea birds were calling out, the sun felt warm on my skin. Even the Greek beer I was drinking had a pleasant taste. It felt good to be alive. My mood was one of sheer delight.
The Unity of Perceptual and Bodily Experiences
79
These experiences and conscious states did not occur in isolation from one another. There was an overall unity in my consciousness, a unity manifest to me in my experience. In what does this unity consist? (20) Consider first my conscious thought: Oh lucky man, am I. As I mentioned earlier, conscious thoughts come wrapped in linguistic auditory images. These images are introspectible to us. They have phonological and stress features. Arguably, they have syntactic features too. For us, in having conscious thoughts, it as if we are producing sentences in a natural language. We can “hear” ourselves speaking internally. (21) The phenomenology of occurrent thoughts derives fundamentally, I maintain, from the phenomenology of their associated linguistic, auditory images.7 This is sometimes denied on the grounds that it is the contents of the thoughts that gives them their phenomenal “feel,” or at any rate that the contents are a factor in their “feel.” But there are strong reasons to deny that this is the case. Consider my consciously thinking to myself, while in the Greek islands, that bottled water is plentiful. There is an associated linguistic image. Imagine taking that image away altogether. Would a conscious thought remain with a distinctive phenomenal “feel”? It seems to me not. Now imagine someone else having a phenomenally identical image but a thought with a different content. Imagine, for example, my molecular duplicate in the twin Greek islands, on Putnam’s famous planet, Twin Earth, who thinks that bottled twin water (or twater) is plentiful. Intuitively, he does not thereby differ from me at the phenomenological level. What he thinks is certainly different from me. His thought has a different content from mine, as witnessed by
80
Chapter 3
the difference in truth conditions for the two thoughts, and if he is conscious of what is thinking, then, in that sense, his thought has a different conscious content. But this is not a phenomenological difference. The difference is simply that he believes that he is thinking that bottled twater is plentiful whereas I believe that I am thinking that bottled water is plentiful. Conversely, suppose that a monolingual Chinese tourist who is visiting the Greek islands at the same time as me consciously thinks that bottled water is plentiful. In this case, our thoughts have the same content. But there is patently a huge phenomenal difference between us. The difference derives from the large difference in the auditory features of which we are aware in having the linguistic images. If the associated images are identical, the thoughts are phenomenally identical; and if the associated images are different, the thoughts are phenomenally different. The phenomenology of a thought derives from its image. (22) What about the phenomenology of thinking, as opposed to the phenomenology of specific thoughts? The obvious way to handle this, given what is said above, is that it derives from the associated images being of the same general phenomenal type: the Chinese speaker and I are both subject to linguistic images that share an “inner” auditory phenomenology. (23) Linguistic auditory images involve the experience of sounds. It is as if, in undergoing the images, we are talking to ourselves. We have the experience of hearing the sounds spoken. The experience is often delusive, of course; for we need not really be speaking to ourselves. But it is still an auditory experience, just as Macbeth’s experience of a dagger was still a visual experience even though no dagger was present.
The Unity of Perceptual and Bodily Experiences
81
(24) Once it is appreciated that the phenomenology of a conscious thought derives from the phenomenology of an associated auditory experience, the question of how the thought is phenomenally associated with simultaneous perceptual and bodily experiences is easily answered. The auditory experience has additional nonauditory features. It is an experience of myself producing certain sounds internally while seeing certain colors, smelling certain smells, and so on. There is a single multifaceted perceptual experience here, as argued in chapter 1. This experience is also bodily: It has a very rich, multimodal, partly bodily and partly perceptual content. What is really unified is the apparent internal pattern of sound and the other experienced qualities of things experienced. And the unity is achieved via the common phenomenal content. No new account is required. (25) Note that it is a consequence of the above position that it is possible to have conscious thoughts with a phenomenology of their own even in the total absence of a body image. What is required are appropriate auditory experiences. And such experiences, as we have seen, can occur in the absence of any bodily feeling. 3.4 Unity and Felt Moods (26) I turn now to the case of felt moods. In the case of emotions, the qualities of which one is directly aware in introspecting felt emotions are frequently localized in particular parts of the body and experienced as such. For example, if one feels sudden jealousy, one is likely to feel one’s stomach sink, one’s heart beat faster, one’s blood pressure increase. Likewise, in the case of the feeling of fear or anger (see Tye
82
Chapter 3
1995a). With moods, however, the relevant qualities are usually not experienced as localized in this way. If one feels delight, as I did entering the harbor of Hydra in the Greek islands, one’s felt mood is usually a combination of things. In my own case, I was thinking to myself thoughts such as these: How beautiful this place is; what glorious weather; how good the sun feels on my skin. My body felt more vibrant too. I somehow felt more alive. As the mood took hold of me, the things I was seeing themselves looked even more beautiful and their colors still brighter in the sunlight. I experienced then a change in myself and my body overall; I experienced various thoughts; and I experienced a change in how the external world itself appeared. This, it seems to me, is typical of what happens when a mood descends. The following remarks,8 from Robert Benchley’s 1921 meditation on the dentistry of the time (entitled “The Tooth, the Whole Tooth, and Nothing But the Tooth”), illustrate these points nicely: Heigh-ho! Here’s the elevator man! A charming fellow! You wonder if he knows that you have just had a tooth filled. You feel tempted to tell him and slap him on the back. You feel tempted to tell everyone in the bright, cheery street. And what a wonderful street it is too! All full of nice, black snow and water. After all, Life is sweet! (1921, p. 83)
(27) Mood experiences represent states of oneself and one’s body, states that were not present before the experiences, as well as in some cases states of the external world. If one feels anxious, for example, one feels various bodily changes and also that disaster or harm is nearby.9 If one feels depressed, one’s experience represents bodily states again and further that one’s actions are unrewarding. In feeling a mood come
The Unity of Perceptual and Bodily Experiences
83
upon one, one feels the new overall represented state. The representation, for exogenous mood experiences, is nonconceptual. One does not need the concept depression to feel depressed. Nor does one need the concept unrewarding. Of course, in some cases, moods are also directed on particular external events or objects. For example, I may feel depressed that I cannot go to Greece this term. But here there are really two things: the feeling of depression and the thought or judgment that I cannot go to Greece this term. The latter is a conceptual representation; the former is not. The latter has a phenomenal “feel” to it via its associated linguistic, auditory image. But that “feel” is over and above the “feel” of the experience of depression. Intuitively, it also seems correct to say that mood experiences represent moods. If one feels elated, it is elation that one feels. Elation is an experience. But elation is also a type of state represented in experience. In this way, moods are like pains, itches, and tickles. Terms for moods in ordinary language do double duty: sometimes they pick out experiences; at other times, they denote experientially represented state types.10 Along with these state types often go various thoughts (positive or negative). (28) Mood experiences are not united with one’s other experiences, for the unity relation, I have argued, is not a relation between experiences. Moods, however, as opposed to mood experiences, that is, moods considered as represented types, are among the relata of the phenomenal unity relation. For example, as I massage my right foot and I feel the numbness in my toes, I curse the day I took up running and a mild depression settles over me. Here, numbness, depression, the color and shape of my foot and toes are united with the auditory qualities that are apparently
84
Chapter 3
tokened by my “inner voice,” as I complain to the God of runners. The unity is achieved by my undergoing a single experience with a highly complex phenomenal content, into which depression and the other qualities enter. (29) This completes my discussion of synchronic phenomenal unity. The account I have offered in the first three chapters of this book is a natural extension of the representationalist approach to phenomenal character (Tye 1995a, 2000). It has the virtues of being straightforward and intuitively plausible. The idea that phenomenal unity comes along with the closure of experience under conjunction is a simple and powerful one. It is an idea that those who multiply experiences and who take phenomenal unity to be a relation between experiences cannot properly accommodate.
4
The Unity of Experience through Time
4.1 Examples of Unity through Time (1) As I rub my forefinger with my thumb and I feel the smoothness of the skin, my experience of smoothness is not merely a succession of independent momentary experiences of smoothness. It is a continuous sensation. This continuing of the sensation is not just an objective fact about it. It is something I experience, or so it is standardly supposed. The streamlike quality of the sensation is itself a phenomenal feature. This is true for experiences generally. My experience of a dull pain that lasts several minutes has a continuous character to it that is itself experienced. Change is experienced too. If my pain suddenly changes from being dull and constant to throbbing, I experience this change in it. (2) Thinking through something, I undergo a sequence of successive thoughts. It is usually held that the continuity in my thoughts, their succession one after another, is something I experience. (3) The persistence of a mood is also experienced. If, for example, I feel melancholy, as I fly back to the cold, wet
86
Chapter 4
climate of England after a summer abroad, my feeling of melancholy seems to descend over me and fill me up. The feeling lasts for quite a while, and, as it does so, I experience its continuing character. (4) What accounts for the unity of our experiences through time? As William James (1952) put it: A succession of feelings, in and of itself, is not a feeling of succession. And since, to our successive feelings, a feeling of their own succession is added, that must be treated as an additional fact requiring its own special elucidation. . . .
The alleged need for such an elucidation is the main topic of this chapter. 4.2 The Specious Present and the Problem of Diachronic Unity (5) Suppose that I am taking part in a psychological experiment and I am listening to a continuing sound. My situation is such that I have an experience with a purely auditory phenomenology. Once the sound begins, at any given moment, I have an experience of a sound with a certain pitch. At each such moment, my experience represents the sound as occurring now. Presentness is part of the content of perceptual experiences in all modalities. The reason why the experience I have of a tiny, twinkling star shape in the night sky, in the case that the star no longer exists, is inaccurate is that I experience the shape as being there now, when in reality at present there is nothing with that shape in the relevant region of the heavens. (6) The present is also experienced when one experiences something changing—a finger moving, say. This experience
The Unity of Experience through time
87
isn’t just a succession of different experiences of the finger in different positions. At any given moment, it is an experience of the movement of the finger. And that cannot occur unless there is an experienced present relative to which movement is itself experienced. This experienced present—the socalled specious present—has a brief but finite duration. It allows us to experience an extended event, such as a continuing sound or a word, or a sequence of events, such as a group of musical notes, all in one as a whole. At any given time in the psychological experiment I have an experience of a sound continuing in the specious present. Just how long the specious present is in objective time is a matter of some dispute. When subjects are presented with two successive stimuli (e.g., two sounds, two flashes of light), they experience one as occurring before the other only if the stimuli are separated in time by 30 msecs or more. For shorter separations, the order of the stimuli is not experienced. Since the experience of A succeeding B requires not just the experience of A succeeded by the experience of B, but rather an experience that encompasses both A and B (in a certain temporal order), it seems plausible to suppose that the specious present is at least 30 msecs long. (7) It is sometimes denied that there really is any specious present on the grounds that the facts it explains can be explained more parsimoniously by appeal to a strictly momentary present and short-term phenomenal memory. Consider, for example, hearing the sequence of musical notes, do, re, mi, in rapid succession. Those who reject the specious present can say that the phenomenal facts in this case may be accounted for by supposing that first, one experiences do; then one experiences re in conjunction with a short-term phenomenal memory of having just heard do;
88
Chapter 4
then finally one has an experience of mi, along with a shortterm phenomenal memory of having just heard re. Patently, however, this won’t do. One has an experience of do followed by re followed by mi; and this experienced temporal sequence has not been explained. It does not help to add that when one experiences mi, one has a short-term phenomenal memory of having just heard do followed by re. For one can only remember having just heard do followed by re, if one has experienced do followed by re; and it is precisely this experience of succession, of do’s being followed by re, that the appeal to memory is supposed to explain. Moreover, no account at all has been offered of the experience of re followed by mi.1 (8) Let us look more closely at the question of when an experience of the present occurs relative to the experienced present. If I have an experience of A followed by B, all in the specious present, then evidently my experience cannot be over objectively before B is experienced to occur, for I cannot experience A before B, unless I experience B. Nor can my experience begin before A is experienced to occur. One possibility, consistent with these claims, is that the experience of A followed by B is backward-looking. That is, it occurs with the experience of B, all in one go, but it represents the temporally extended period of A’s preceding B. On this account, the experience of A followed by B casts an eye backward, as it were, at what preceded it. The glance is all-in-one, however. It takes in a succession in the specious present—the time that, for the experiencer, is now. See figure 4.1. (9) Another possibility is that the experience of A followed by B is a complex experience that continues for the same time period as the specious present, and which has as parts
The Unity of Experience through time
89
Momentary experience
[A followed by B]
NOW
Figure 4.1 The experience of A followed by B in the present shown here as occurring after the specious present.
Experience of A followed by B Exp of A followed by Exp of B
[A
followed by
B]
NOW
Figure 4.2 The experience of A followed by B in the present shown here as occurring at the same time as the specious present.
an experience of A followed by an experience of B, where the times of the experiences of A and B match the times at which A and B are experienced to occur. See figure 4.2. (10) It is sometimes argued that only the second of these possibilities is viable on the grounds that the first violates a principle called by Miller (1984) the principle of presentational concurrence (PPC). According to Miller,
90
Chapter 4
The duration of a content being presented is concurrent with the duration of the act of presenting it. . . . [T]he time interval occupied by a content which is before the mind is the very same time interval which is occupied by the act of presenting that content. (p. 107)
Miller’s principle is endorsed by Barry Dainton (2000). He comments: PPC does seem plausible. When I see the red flash followed by the green flash, or when I hear a sequence of notes C-D-E, my experiencing of the succession does seem to run concurrently with the phenomenal contents which jointly constitute the succession. . . . I am aware of the red flash before I am aware of the green flash. (p. 134)
(11) It seems to me that there is a serious confusion here. Granted, I experience the red flash as being before the green one. But it need not be true that my experience or awareness of the red flash is before my experience or awareness of the green one. If I utter the sentence The green flash is after the red flash, I represent the red flash as being before the green one; but my representation of the red flash is not before my representation of the green flash. In general, represented order has no obvious link with the order of representations. Why suppose that there is such a link for experiential representations? (12) Moreover, there are well-known experimental effects that provide clear reasons for favoring the first “backwardlooking” proposal. One of these is the colored phi phenomenon. Here a red spot is lit for 150 msecs, then 50 msecs later a second displaced green spot is lit for another 150 msecs. Subjects report that they experience a red spot moving and changing color abruptly to green in midcourse toward the location of the green spot. Subjects thus experience red first, then red-switching-to-green, then green; and this all occurs
The Unity of Experience through time
91
within a single specious present. Obviously, the subjects cannot experience red-switching-to-green unless they have already registered the greenness of the second spot.2 So, the subjects’ illusory experience of red-turning-to-green-inmidpath cannot occur at least until their experience of the green spot occurs—just as the “backward looking” account of the experience of the specious present predicts. (13) Another striking effect is the flash-lag illusion. This was first noted in 1958, but only very recently has its relevance to our visual experience of the present been investigated carefully. In this case, subjects are initially presented with a moving ring or hoop in the middle of which there is a sudden flash of light. Subjects report that the flash is experienced as lagging behind the ring or hoop. One explanation proposed for this effect has been that the subjects’ brains make the assumption that the ring will keep moving in the same direction and extrapolate its position forward so that the subjects experience the flash as lagging behind. But, as Eagleman and Sejnowski (2000) have shown, this hypothesis cannot account for subsequent variations on the experiment in which the motion of the ring is stopped at the moment of the flash or reversed. In the both of these cases, the proposed explanation predicts that the subjects should experience the flash as lagging behind the ring in the original direction of motion. But what subjects actually experience in the first case is the flash as occurring right in the center of the ring and in the second as trailing behind in the opposite direction to that of the original motion. These results support the view that our brains collect information a little into the future before an experience is generated, so that what we experience as the present is in reality a little in the past, just as the “backward-looking” proposal supposes.
92
Chapter 4
Other related experiments by Eagleman and Sejnowski yield the same result. For example, they found that if the ring is stopped motionless at the time of the flash and then moves immediately afterward, the illusion still occurs: the flash is experienced as lagging behind in the direction of the movement. This result proved robust up to a delay in movement of the ring of up to 80 msecs. (14) A further question concerns the relationship between adjacent specious presents where there is experienced continuity from moment to moment, as with the case of the persisting sound in the psychological experiment. It will not do to say simply that the specious presents follow one another in objective time so that the next one begins as the last one ends. For this gives us no more than a succession of experiences of sound. There is nothing here yet to account for the experienced continuity of the sound from one present to the next. (15) A more promising proposal, made by several philosophers (e.g., C. D. Broad 1923) is that adjacent specious presents overlap, as shown in figure 4.3. On this view, part of
Objective time scale
Figure 4.3 Two overlapping specious presents.
The Unity of Experience through time
93
the sound that is experienced in any given present is also experienced in the next present. In this way, the experience of sound supposedly continues from one present to the next. (16) One objection that has been raised repeatedly to this proposal (by Mabbott 1951, Foster 1979, Sprigge 1993, and Dainton 2000) is as follows. Suppose that the constant unvarying sound I am experiencing is interrupted by a single sharp click, C, which occurs within the region of overlap of two adjacent specious presents, as shown in figure 4.4. The click is heard once in the first specious present (t1–t3) and once again in the second specious present (t2–t4). It follows that the click is heard twice over. This, it has been claimed, is a disastrous result, since by hypothesis there is only a single click that is experienced by the subject (Dainton 2000, p. 141). (17) This objection is ineffective. Suppose that there are indeed two different token experiences of the click C, one for each specious present; suppose also that each experience occurs objectively at the end of the relevant present (i.e., at t3 and t4),3 so that the click is experienced at two different times. Still, it would be a mistake to infer from this that a
C
Objective time
t1
t2
t3
t4
Figure 4.4 The click C occurring in the region of overlap of two adjacent specious presents.
94
Chapter 4
click is experienced as being at two different times or that I, the subject, have an experience as of two clicks. I hear a click twice in that there are two times at which an act of hearing a click occurs, namely, t3 and t4. But the times, t3 and t4, have no time between them at which I experience that there is no click. Indeed, there is no time between these two times at which anything is experientially represented by hearing. So, I do not hear a click as occurring twice. It does not seem to me that there is a click followed by a second click. No difficulty as yet, then, for the proposed overlap account. (18) Nonetheless, there remains a serious problem. For even if adjacent specious presents overlap in objective time, this does not suffice to generate the experience of continuity from one present to the next. Suppose that I hear the scale do–re–mi. Suppose that do–re occupies the first specious present and re–mi the next, so that re is experienced in the first specious present and also in the second, as shown figure 4.5. On this proposal, I experience do–re and I experience re–mi, and, in fact, what I experience in the first case overlaps time-wise with what I experience in the second. But this no more suffices for an experience of do–re–mi than my saying do–re and your saying re–mi, where your remark begins before mine ends, suffices for there to be a saying of do–re–mi.
[do
re]
[re
mi]
Objective time
Figure 4.5 The experience of do–re overlapping with the experience of re–mi.
The Unity of Experience through time
95
The example just given of saying involves two speakers. But two subjects need not be involved. Suppose, for example, that I consciously desire a beer followed by a whiskey. Before this desire slips from consciousness, I have the further conscious desire for a whiskey followed by another whiskey. I do not have here a desire for a beer followed by a whiskey followed by another. Knowing full well that, in the circumstances, three alcoholic drinks will make me ill, I desire to drink only two. Alternatively, consider the case in which I think that breakfast is four hours before lunch and I also think that lunch is six hours before dinner, where these two thoughts overlap temporally as in the examples above. In having these thoughts, I do not have a single thought whose content is that breakfast is fours hours before lunch, which is six hours before dinner. (19) What is needed, it seems, in the case of experiencing the musical scale, is a further experience, over and above the experience of do–re and the experience of re–mi, an experience that unifies those experiences into a phenomenal whole. Generalizing, it seems that the experience of continuity or succession requires that there be an overarching experience that unifies successive individual experiences, each of the specious present and its contents. Viewed in this way, the problem of the unity of experiences through time is to specify the phenomenal unity relation that connects token experiences at different times and binds them together into a single larger experience. 4.3 An Account of Unity through Time (20) The problem, posed in this way, is no more real than the problem of the unity of experiences at a time; for there is no relation of unity between token experiences that is given to
96
Chapter 4
us in introspection. When we introspect, we are not aware of our experiences at all. As explained in chapters 1 and 2, we are aware of things outside, of changes in our bodies or ourselves, and of various qualities these items are experienced as having. Thereby we are aware that we are having such and such experiences. But we are not aware of the token experiences themselves. So, we are not aware of our experiences as unified or as continuing through time or as succeeding one another. And if this is the case, why suppose that that unity through time is a relation between token experiences at different times? (21) The basic intuition with respect to unity through time is surely that things and qualities we experience at successive times are experienced as continuing on or as succeeding one another. Consider again the case in which I have an experience of a red flash followed by a green flash. Here I experience two colored flashes as occurring one after the other. I do not experience my experience of a red flash as succeeding my experience of a green one any more than I experience my experience of a red flash as red. Moreover, if I introspect my experience of a red flash followed by a green flash, I do not discover an experience of a red flash and then after it an experience of a green one. Via introspection, I am not aware of any inner particulars at all. I am aware that I am having an experience of a red flash followed by a green one, but I am not aware of two different particular experiences, one of a red flash and one of a green one. Of course, I am aware of the qualities, red and green. But I am aware of these as qualities of flashes, not as qualities of my experiences. (22) What is true here for the experiences of red and green flashes is true for other experiences. If I experience a loud,
The Unity of Experience through time
97
high-pitched sound, it is the auditory qualities of the sound that are experienced as continuing from moment to moment; if I feel a pain in a thumb, it is the changing qualities of the disturbance I experience in my thumb that are experienced by me, as the pain starts to throb and intensify. Continuity, change, and succession are experienced as features of items experienced, not as features of experiences. (23) In the earlier example of hearing the musical scale, do–re–mi, there is an experience of all three notes, with each note being experienced as flowing into and being succeeded by the next. As the scale ends, it is succeeded by something else—something accessible either by hearing or by another sense—provided that consciousness continues. With each experienced change in things and qualities, there is an experience of the change. But this does not necessitate that there be a new experience. The simplest hypothesis compatible with what is revealed by introspection is that, for each period of consciousness, there is only a single experience— an experience that represents everything experienced within the period of consciousness as a whole (the period, that is, between one state of unconsciousness and the next). (24) Admittedly, this hypothesis may seem to be at odds with such everyday statements as “I had many strange experiences today.” But in reality there is no conflict. Talk of my undergoing many strange experiences no more requires for its truth that there exist multiple strange experiences than does talk of my having a drowning feeling require that there be a feeling that drowns. Just as in the latter case it suffices that I undergo an experience that represents that I am drowning so too in the former it suffices that my experience today represented many strange things.
98
Chapter 4
(25) The one experience hypothesis finds further support in the general difficulty we face in individuating experiences though time. Consider an ordinary visual experience and suppose that it is exclusively visual. When did it begin? When will it end? As I write now, I am sitting in a library. Looking ahead, and holding my line of sight fixed, I can see many books, tables, people in the distance walking across the room, a woman nearby opening some bags as she sits down. Is this a single temporally extended visual experience? If not, why not? It may be tempting to say that this is a single token experience on the grounds that the same visual scene is before my eyes. The visual scene changes somewhat through time, as people move around, but that doesn’t make it a different scene, any more than the changes through time in my car make it another car. But what if I am hallucinating the scene and there is really nothing before my eyes? What if the people and things in the scene are replaced by replicas and that this is done by God without there being any noticeable change, as far as I am concerned? In the latter case, there is another scene, a duplicate of the original but a different scene nonetheless. Do I continue to undergo the same token experience? These cases perhaps suggest that as long as apparently the same visual scene is present, the same token visual experience is present. But what if I fall asleep and reopen my eyes later, with the scene apparently unchanged? Same token visual experience then? Intuitively not (if I am the subject of multiple visual experiences at all). Likewise, if I see a flash of lightning in the sky one night and the next night I see another flash that looks indistinguishable from the first. So, neither real sameness of visual scene before the eyes nor apparent sameness in visual scene suffices to individuate
The Unity of Experience through time
99
purely visual experiences; and with multimodal experiences the situation is still more murky. These difficulties of individuation arise once it is assumed that the stream of consciousness divides into different token experiences, usually longer than the specious present, that come and go. The difficulties disappear if it is held instead that each stream of consciousness is itself just one temporally extended experience. (26) As noted in chapter 1, experiences, on my view, are maximal PANIC states. For each such state, there is a momentary phenomenal character (what it is like to undergo the experience at a particular moment) and an overall phenomenal character (what it is like to undergo the experience from beginning to end). The phenomenal character of an experience at any given moment is its PANIC at that moment. The overall phenomenal character of an experience is its overall PANIC. It seems to me natural to suppose that experiences have stages; and it also seems plausible to hold that these stages have phenomenal character. But experience stages are not experiences, any more than undetached cloud parts are clouds. (27) Here is a parallel. Consider a movie depicting a complex series of events taking place during an extended period of time. The movie has a very rich representational content overall. It is a movie about war; it is a movie about peace. It is a movie about the fall of the Russian aristocracy. The movie can be boring at some times and exciting at others; for what it depicts at different times varies. Even so, there is just one movie, not many movies unified together into one encompassing movie. So too, I claim, with experience. (28) In taking this view, I am not denying that, in the example of my hearing the musical scale, do–re–mi, there is an experience of do–re in the first specious present and an
100
Chapter 4
experience of re–mi in the second. My point is that these are not different experiences: there is only one experience—an experience of do–re–mi—that has been described in different (partial) ways, an experience with different stages to it. (29) What, then, is phenomenal unity through time? Let us distinguish between direct and indirect unity. Direct phenomenal unity through time is a relation between experientially represented qualities. It obtains if and only if the qualities experienced in one specious present are experienced as succeeding or continuing on from the qualities experienced in the immediately prior specious present. Indirect phenomenal unity through time is also a relation that obtains between experientially represented qualities. It obtains if and only if the qualities experienced in nonadjacent specious presents are linked by chains of direct phenomenal unity. Indirect unity is thus the ancestral of direct unity. Chains of experienced succession and flow from one specious present to the next bind together qualities experienced as instantiated in nonadjacent specious presents into a shared phenomenal content (where, as before, the phenomenal content of an experience is the part of its overall content that endows it with its phenomenal character). With a break in the chain, there is an end to the period of consciousness and an end to the continuing experience whose phenomenal content encompasses that period. (30) In the case that consciousness is unified through time, the claims (1) Person P has an experience of an F and (2) Person P has an experience of a G
The Unity of Experience through time
101
jointly entail (3) Person P has an experience of an F and a G, just as they do in the case of unity at a time. The difference is merely that, with unity through time, the relevant experienced times for (1) and (2) are not the same (and (3), of course, is not to be read as saying that P has an experience of F and G at the same time). Unity through time, both direct and indirect, comes with the closure of experience under conjunction just as unity at a time does. (31) The proposal I am making leaves open how succession itself is represented in the vehicles of phenomenal content. Take, for example, the case of my experiencing a bright flash now, followed by a loud noise now, where one now immediately follows the other. The brightness of the flash in my experience is succeeded phenomenally by the loudness of the noise. Since introspection gives me no access to the vehicle of representation, it does not reveal to me the means by which succession is represented. Perhaps the relation of succession is represented by a part of the experience just as the relation of loving is represented by a part of the sentence “Tom loves Mary.” Perhaps succession is represented by a relation between parts of the experience. That, I maintain, is an empirical matter on which the present proposal is silent. In taking no stand on this issue, I want to emphasize that I am not leaving open the nature of phenomenal succession. My claim is that phenomenal succession is a relation between qualities that enter into the phenomenal content of the single experience of the subject for the given period of consciousness—a relation that connects qualities instantiated in adjacent specious presents, if the experience is veridical.
102
Chapter 4
4.4 Some Mistakes, Historical and Contemporary (32) With this proposal, we have a solution to, or better, a dissolution of, at least one version of the problem that defeated Hume and led him to confess: But all my hopes vanish, when I come to explain the principles that unite our successive perceptions in our thought and consciousness. (1739)
Hume’s mistake was to suppose that there is a unifying relation connecting successive perceptions in the first place. Unity is a relation between qualities experienced, at least insofar as the kind of unity under discussion is phenomenal. So, there simply aren’t successive perceptions or experiences that are unified with one another. Indeed, there aren’t successive perceptions or experiences at all within the same period of consciousness. James’s supposed fact, that there is an additional feeling of the succession of feelings requiring its own elucidation, is not a fact at all. A succession of feelings is indeed not a feeling of succession. But a feeling of succession is not a feeling of the succession of feelings either. Where consciousness is unified, there is only a single feeling, a feeling that can be described in multiple ways as a feeling of succession, as a feeling of A succeeding B, as a feeling of A, as a feeling of B, as a feeling of A and B, and so on. (33) The above proposal does not as yet provide an account of personal identity; for split-brain subjects have a disunified consciousness without thereby splitting into two separate people. And here, it may be argued, there is a difficulty lurking for the position I am taking. To see this, consider a split-brain patient whose corpus callosum is cut while he retains consciousness. The operation disunifies the consciousness of the subject.4 On the proposal I have made,
The Unity of Experience through time
103
t
t⬘
E1
E2
T
t ⬘⬘
Figure 4.6 Two experiences (E1 and E2) after the brain bisection (at t) and one before.
it follows that there are two experiences after the operation, but only one before, as shown in figure 4.6. How can this be? (34) The obvious reply is that in such a case of fission, experience E1 is identical with experience E2 for time period t to t and different from E2 for time period t to t. No contradiction ensues from this claim, since identity at a time is not identity simpliciter (Lewis 1976). E1 is different from E2 since they differ in some of their stages and thus do not share all the same properties. E1, for example, has a stage that causes its owner to react in one way at time T after the operation, while E2 has a stage that causes its owner to react quite differently at that time. E1 is identical with E2 for the period t to t, since every stage of E1 within that time period is identical with some stage of E2 and vice versa. E1 and E2
104
Chapter 4
share all their stages prior to t, but after t, their stages diverge. It is no good objection to this view, incidentally, to say that if there are two streams of consciousness, then there were two all along; for identity proper is tenseless. There are indeed two streams of consciousness but not two streams at all times. Prior to fission, there is just one stream (E1 is identical with E2 at all prefission times). After fission, there are two streams (E1 is distinct from E2 at postfission times). (35) Another reason the above proposal does not provide directly an account of personal identity is that even in the case of normal people, one and the same person is subject to many extended experiences or streams of consciousness during her lifetime. If I fall into a deep sleep, I often lapse into a state of unconsciousness. When I wake up again, a new stream of consciousness begins. My life is made up, at the psychological level, of consciousness punctuated by unconsciousness.5 (36) In the last paragraph, I characterized extended experiences as streams of consciousness. Some have argued that human consciousness really isn’t streamlike at all. Galen Strawson remarks: William James’ famous metaphor of the stream of consciousness is inept. Human thought has very little natural phenomenological continuity or experiential flow if mine is anything to go by. . . . It keeps slipping from mere unconsciousness into self-consciousness and out again. . . . It is always shooting off, fuzzing, shorting out, spurting, and stalling. (1997, p. 421)
He continues: When I am alone and thinking I find that my fundamental experience of consciousness is one of repeated returns into consciousness
The Unity of Experience through time
105
from a state of complete if momentary unconsciousness. The situation is best described, it seems to me, by saying that consciousness is continually restarting. (1997, p. 422)
We can agree with Strawson that human thinking is full of stops and starts. But this observation does not undermine the stream metaphor. For consciousness is largely a matter of perceptual experience, bodily feeling, and mood. This phenomenal background is there all the time we are awake, and it has a kind of continuity or flow to it. When we stop thinking about something, it is not as if all goes dark! We do not thereby slip into a state of complete unconsciousness. If I think hard about something and then pause for a bit, perhaps then thinking for a moment about an appointment later in the day, there is a common conscious background for these thoughts, a background to which I may not be paying attention, but which is still certainly there. Oddly, Strawson seems to grant these points a little later. He writes: [C]onsciousness is in perpetual flux, and different thoughts and experiences succeed one another with inconceivable rapidity (Hume). And yet one is experientially in touch with a great pool of constancies and steady processes of change in one’s environment including notably one’s body. . . . (1997, p. 422)
A better way, I suggest, to describe the facts to which Strawson is trying to draw our attention is to say that thinking involves a kind of turbulence within the overall stream. Where it occurs, there is no extended continuity as far as the phenomenology of the thinking process is concerned. But the stream of consciousness is still there, flowing on from moment to moment. What thinking adds phenomenologically is primarily an inner voice.6 One experiences oneself speaking in one’s native language, with the usual pattern of
106
Chapter 4
stress and intonation, the words expressing the thought. One’s stream of consciousness, for the time of the thought, thereby includes within its overall phenomenal content that so-and-so sounds are coming from within. (37) Can there be a single stream of consciousness with objective time gaps in it? It seems to me that there can. Consider first this case. Suppose again that I am listening to the scale, do–re–mi, as I fall asleep. The last thing I hear is the note, re. On awakening, after a period of unconsciousness, the first thing I hear is the note, mi. I remember hearing the note, re, as I hear mi, but I do not experience the transition between re and mi. I do not experience the succession of re by mi. Here there are clearly two different streams of consciousness, two different token experiences with an objective time gap between them. Consider now the following case. Once more, I am listening to the scale, do–re–mi. This time, just as I finish hearing re, God instantaneously freezes all my internal physical states as well as all physical processes in my surrounding environment for an extended period of time—five years, say—and then unfreezes them instantaneously. In this case, I do experience the succession of re by mi.7 The transition from one note to the next is given to me in the phenomenology of my experience. There is thus a single stream of consciousness with an uninterrupted phenomenal flow, a stream that objectively has a five-year gap in it. 4.5 Carnap and the Stream of Consciousness (38) The view I have been defending is not entirely without historical antecedent. Rudolf Carnap in his book, The Logical Structure of the World (1967), held that entire streams of consciousness are the basic elements of experience.
The Unity of Experience through time
107
According to Carnap, streams of consciousness are noncomposite in that they lack individual experiences as parts. Carnap did not deny that we talk as if there are particular experiences within the overall stream, but he claimed that ontologically this talk is not perspicuous. Carnap appears to have been motivated in part by the belief that “we have to proceed from that which is epistemically primary, that is to say, from the given, i.e., from experiences themselves in their totality and undivided unity” (1967, p. 67). In Carnap’s view, prior to any learning, we are given only the entire streams. Subsequent categorizations then divide up the streams in various ways. (39) The present proposal is motivated not at all by claims of an epistemological sort about the learning process. The argument I have given is that the proposed view best accounts for the facts of unity at a time and unity through time. Nothing that we ordinarily say about experience needs to be given up. No large bullets need to be swallowed. The view is clear and simple; and it explains in a compelling way why the problems of unity for experience seem so intractable. Begin with the assumption that there are individual experiences somehow bundled together by a phenomenal unity relation to form an overarching experience and you will find yourself either supposing that phenomenal unity is something unique and basic about which you can say nothing else at all except that it bundles experiences together to form a unified consciousness, or you will join Hume in confessing that the problem of the unifying principle is too hard to be solved. The latter course of action at least has the virtue of candor, but the best strategy, it seems to me, is simply to give up the assumption. (40) Once the assumption is dropped, we have a straightforward explanation of why, contra Strawson, it seems so
108
Chapter 4
very natural to talk of our consciousness forming a stream. Streams of water begin and end. They are sometimes calm and smooth; at other times rough and turbulent. Streams of water flow. They do not contain within themselves other shorter streams. Nor do they divide into multiple constituent streams all of the same length as the streams containing them. See figure 4.7. So it is, I claim, with experience or consciousness. Consciousness forms a stream. It begins and ends. Its content is sometimes monotonous. At other times, it is rich and varied. Within consciousness, there is a phenomenal flow, revealed in its content. A stream of consciousness is just one temporally extended experience that represents a flow of things in the world. It has no shorter experiences as parts. Indeed it has no experiences as proper parts at all.
Figure 4.7 Streams are not as shown. They do not contain multiple constituent streams.
5
Split Brains
5.1 Results of Splitting the Brain (1) The human brain is divided into two more or less symmetrical hemispheres. The surgical removal of one of these hemispheres does not eliminate consciousness, and neither does cutting the many connections of the corpus callosum between the hemispheres. The latter operation, originally performed by Roger Sperry in the 1960s on some epileptic patients with the aim of controlling epileptic seizures, has a remarkable consequence. In addition to reducing greatly the number and intensity of the seizures themselves, it also produces a kind of mental bifurcation in the epileptic patients. (2) Here is an illustration. A subject, S, is told to stare fixedly at the center of a translucent screen that fills his visual field. Two words are flashed onto the screen by means of a projector located behind, one to the left of the fixation point and one to the right, for example, the words ‘pen’ and ‘knife’. The words are flashed very quickly (for just 1/10 of second) so that eye movements from one word to the other are not possible. This arrangement is one that ensures that the word on the left provides input only to the
110
Chapter 5
Figure 5.1 The two hemispheres divided.
right hemisphere of the brain and the word on the right provides input only to the left. S is then asked what he saw. S shows no awareness, in his verbal responses, of ‘pen’. However, if S is asked to retrieve the object corresponding to the word he saw from a group of objects concealed from sight, using his left hand alone, he will pick out a pen while rejecting knives. Alternatively, if S is asked to point with his left hand to the object corresponding to the word he saw, he will point to a pen. Moreover, if S is asked to sort through the group of objects using both hands, he will pick out a pen with his left and a knife with
Split Brains
111
his right. In this case, the two hands work independently with the left rejecting the knives in the group and the right rejecting the pens. (3) Interestingly, split-brain subjects, when first asked to use the left hand to identify objects out of sight by touch from among a group of such objects, commonly say that they “cannot work with that hand” or that it “is numb.” After they successfully identify a series of objects and are asked how they could have done this if they are unable to feel the objects, they say things like “Well, I was just guessing” or “Well, I must have done it unconsciously” (Sperry 1968). There is much more data, some of it fascinating. For example, a smell presented to the right nostril will lead the split-brain subject to deny verbally that there is any smell; but if asked to point with his left hand at the object with the smell, he will pick out a clove of garlic, while continuing to deny that there is a smell and insisting verbally that he thus cannot point to what smells. In another experiment (noted in Nagel 1971), the subject is told to hold an object in his left hand, a pipe, say, out of sight and to write down afterward with his left hand what he was holding. The subject slowly starts to write ‘P’ followed by ‘I’. Then the writing speed increases, with the subject changing the ‘I’ to an ‘E’ and the word being completed as ‘PENCIL’. Here, it seems, the verbal left hemisphere has taken control and made a guess as to the appropriate word, based on the appearance of the first two letters. Then the right hemisphere regains control, with the word ‘pencil’ being deleted and a picture of a pipe being crudely drawn in its place. (4) What are we to make of these results? It has been variously suggested (a) that split-brain subjects are really two
112
Chapter 5
persons with two separate minds; (b) that the responses produced by the right hemisphere are those of an unconscious automaton; (c) that it is indeterminate how many persons split-brain subjects are and that the concept of a person is thrown into jeopardy by the experimental results; (d) that split-brain subjects have a unified phenomenal consciousness but a disunified access consciousness; (e) that splitbrain subjects are single persons who undergo two separate
Split Brains
113
streams of consciousness that remain two from the time of the commissurotomy; (f) that split-brain subjects are single persons whose phenomenal consciousness is briefly split into two under certain special experimental conditions, but whose consciousness at other times is unified. (5) The most plausible view, I shall argue, is (f). I shall also argue that the best explanation of certain experimental results for split-brain subjects requires that the phenomenal unity relation be nontransitive. This, as we shall see, offers further support for the account of unity I have been defending. 5.2 Multiple Personality Disorder, Split Brains, and Unconscious Automata (6) Consider, to begin with, a case of multiple personality disorder. Suppose that Richard Readiweather is a loudmouthed, beer-swilling, football-loving auto-worker from Michigan. He cares not at all what others think of him, least of all his mother, to whom he pays no attention, visiting her only once a year. His favorite football team, so he says, is the University of Michigan and he is an avid fan. All is not well with Richard. At times, he becomes quiet and introspective. On these occasions, he says that his name is “Claude” and he insists that he hates football and beer. When asked why he goes to all the University of Michigan games, he explains that if he didn’t go, it would upset his mother, who is an avid supporter of Michigan football (even though she is herself too old now to attend the games), and he definitely does not want to offend his mother. When queried about his seeing his mother only once a year, he says that she needs her space and that he thinks lovingly of her all the time. Concerning the ten beers he drinks on a daily basis, he
114
Chapter 5
insists that he hates the taste of beer, but he believes that it is of great medicinal value. Ten beers a day keeps the doctor away, he says, in a soft, somber tone. (7) These differences and others of a similar sort between Richard and Claude make it very difficult to suppose that there is but a single person, a single mind present. Richard and Claude each have a set of propositional attitudes with an internal coherence. Where one has a given attitude, the other, in many cases, lacks it. Richard likes the taste of beer; Claude does not. Richard is indifferent to his mother; Claude loves her. Richard enjoys football and he believes that football is a wonderful game; moreover, he wants to see the University of Michigan football games more than any other. Claude doesn’t enjoy football, he doesn’t believe that football is a wonderful game, and he doesn’t really want to see the University of Michigan games, but he goes anyway for his mother’s sake. One and the same person cannot both
Split Brains
115
believe that P and not believe that P or desire that P and not desire that P in the way that Richard and Claude do. Richard and Claude thus are two persons, with two minds. (8) Split-brain patients are not like this. Overall, their behavior is just like that of normal people. There is a unity, an integrated character to the functioning of split-brain patients outside of certain very special, experimental situations. They walk, run, swim, play the piano, and engage in any number of everyday activities in the normal way. Moreover, they do not report any breakdown or division in the visual field. How could this be, if split-brain patients are really two different persons? Split-brain patients typically act as if they are single persons with a unified conception of the world and what is going on around them. Those who know split-brain patients cannot help but think of them and relate to them as single subjects (Nagel 1971). (9) Still, it might be insisted, in the relevant experimental situations at least, it must be conceded that two persons are present, even if before the experimental controls are imposed and after they are removed, there is just a single person. For consider again the split-brain patient who has the word ‘pen’ flashed on the left of the screen and the word ‘knife’ on the right. He believes that he saw ‘pen’ (since he reaches for a pen with his left hand when asked to pick out from a group of objects the one corresponding to the word he saw) and he believes that he saw ‘knife’ (since, when asked what he saw, he verbally reports, “the word ‘knife’ ”). Given that he doesn’t say ‘pen’, when asked what he saw, it seems that he doesn’t believe that he saw ‘pen’. And given that he doesn’t reach with his left hand for a knife in the group of objects, it seems that he doesn’t believe that he saw ‘knife’. One person cannot both believe that P and not
116
Chapter 5
believe that P at the same time. So, the split-brain patient is really two persons, albeit for a short period of time. (10) There is a mistake in this reasoning. The fact that the split-brain patient doesn’t say ‘pen’, when asked what he saw, doesn’t show that he doesn’t believe that he saw ‘pen’. He does believe that. It’s just, given the commissurotomy, he can’t verbally express the belief. To be sure, if the patient is asked whether he saw ‘pen’, he will respond ‘no’, and this is evidence that he believes that he didn’t see ‘pen’. But believing that not-P isn’t the same as not believing that P; nor does the former necessitate the latter. Likewise, the fact that the split-brain patient doesn’t reach for a knife, when told to pick out with his left hand the object corresponding to what he saw, doesn’t show that he doesn’t believe that he saw ‘knife’. The fact that he declines taking a knife with that hand, when offered one as a candidate for the object corresponding to the word he saw, shows that he believes that he didn’t see ‘knife’. But one and the same individual can certainly believe that P and believe that not-P at the same time (or desire that P and desire that not-P). There are many such examples in everyday life. Consider Jonathan’s wanting a Ferrari and his wanting not to have Ferrari (given the unreliability of Ferraris, the cost, the worries involved, etc.); or Samantha’s saying sincerely that people, whatever their skin color, should be treated alike, while always choosing to sit next to white people on the bus she takes to work. Or take my believing that sunny weather is wonderful, as I sit relaxing by the pool, and my also believing at that time that sunny weather is not so terrific (given its effects on the skin, etc.). The latter belief, of course, may not be manifested in any conscious thought I have, as I enjoy the sunshine by the pool. But it would have been, had I turned my thoughts to the issue of health.
Split Brains
117
(11) So, the first hypothesis about split-brain patients (which is endorsed by Sperry 1968)1 is a nonstarter. What of (b), the hypothesis that the responses produced by the right hemisphere are those of an unconscious automaton? Again, this cannot be right. The right hemisphere responses are not especially intelligent and, of course, speech production lies beyond its power. But speech comprehension takes place there, and the right hemisphere can perform a variety of tasks demanding dexterity and discrimination, for example, spelling out words with wooden or plastic letters. The right hemisphere has no difficulty in following the experimenter’s instructions and in performing tasks for which attention and concentration are needed (e.g, picking out the relevant object from a group of concealed objects). If consciousness is denied to the right hemisphere, there seems no reason not to extend the denial of consciousness to mutes or to prelinguistic children. 5.3 Indeterminacy in the Number of Persons (12) The hypothesis that it is indeterminate how many persons a split-brain subject is comes from Nagel (1971). According to Nagel: We assume that a single mind has sufficiently immediate access to its conscious states so that, for elements of experience . . . , the mind which is their subject can also experience the simpler relations between them if it attends to the matter. Thus, we assume that when a single person has two visual impressions, he can usually also experience the sameness and difference of their coloration, shape, size, the relation of their position and movement within his visual field, and so forth. The same can be said of inter-modal connections. The experiences of a single person are thought to take place in an experientially connected domain, so that relations
118
Chapter 5
among experiences can be substantially captured in experiences of those relations. Split brain patients fail dramatically to conform to these assumptions in experimental situations, and they fail over the simplest matters. Moreover, the dissociation holds between two classes of conscious states each characterized by significant internal coherence. (1971, p. 407)
Nagel continues: These considerations lead us back to the hypothesis that the patients have two minds each. (1971, p. 408)
But this is untenable, according to Nagel, given the overall behavioral integration exhibited by split-brain patients. The upshot supposedly is that there is no whole number of minds these patients have! And this, in turn, should lead us, Nagel thinks, to be skeptical about the concept of a single subject of consciousness. (13) I am unconvinced. Recall the case I imagined in chapter 3 of the person, buried in a horizontal position in sand, whose eyes and ears are moved away from his body above the sand, while the relevant neural connections are stretched but remain intact. This person is put in this state while unconscious and wakens to have an audiovisual experience of himself on a roller coaster (as presented to him by his eyes and ears in an IMAX theater) while simultaneously having tactual and bodily experiences of being motionless, surrounded by sand. He has an experience of something A and an experience of something B, but he cannot connect A to B in his experience. It is as if he is in two spatially disjoint worlds. He wonders, of course, how this could be happening. In so doing, he wonders how he could be experiencing both these things. “What has happened to me?” he asks
Split Brains
119
himself. “How could I be experiencing the things I am?” Perhaps, if he is clever enough, he can work out what must have happened. Be that as it may, there seems no question here that there is a single subject. And this subject does not conform to Nagel’s assumptions. (14) There are other cases. People who have impairments in their ability to visually recognize spatial relations between things often have corresponding impairments in imagery. They are able to draw or describe the visual appearances of things in scenes no longer present, for example, a chair, a sofa, a lamp, a clock in a familiar sitting room, but they do poorly at drawing or describing the spatial arrangements of those things.2 For these people, it is as if, when they view the scene originally, experiences are generated of the different items in it without there being any conscious experience of their spatial relations. (15) One might respond that in both the above cases the subjects experience certain spatially unconnected items together. So, there is at least an experience of the relation of unity or togetherness. This is not clear, however. Take the example of the people with object-centered “tunnel vision.” These people are blocked from any interobject comparisons. As they focus on one object, they lose cognitive awareness of the other objects. It certainly seems conceivable that this cognitive deficit is mirrored at the level of the experiences themselves on which the cognitive responses are based so that there is no experience of different things together. And extending the example in this way surely should not lead us to the conclusion that two persons are present undergoing the experiences! Still, Nagel is right to say that, for split-brain patients, there are two classes of mental states characterized by an
120
Chapter 5
internal coherence, at least if he has in mind attitudes and experiences present while the experimental controls are still in play. But, as emphasized earlier, these two classes are not like those undergone by individuals with a multiple personality disorder who really are two different persons. Splitbrain patients do not both believe that P and not believe that P, want that P and not want that P, experience that P and not experience that P. (16) Nagel also comments that we have no clear idea of what it is like for split-brain patients, and further that we cannot project ourselves into their mental lives. But this, I suggest, is confused. There is nothing it is like to be in the state the split-brain subject, S, is in, as he views the words ‘pen’ and ‘knife’ flashed up onto the left and right sides of the screen before his eyes. For insofar as there is any such thing as the state S is in at the given time, it is a conjunctive state, namely, the state of experiencing ‘pen’ and experiencing ‘knife’. That state is not itself an experience, even though its conjunctive components are. So, there is nothing it is like for S to undergo the conjunctive state and, generalizing, nothing special it is like for split-brain subjects. Of course, there is something it is like for S to experience ‘pen’, and further there is something it is like for S to experience ‘knife’. But what these states are like is just what they are like for anyone else. So, in one sense, we can project ourselves into the mental lives of split-brain patients: we know just what it is like to experience each experience a split-brain subject undergoes. What we cannot do is to imagine ourselves undergoing both the visual experiences a split-brain subject experiences at any given moment while the experimental controls are in place and simultaneously being aware, all in one introspective act, of the content of each. In this respect,
Split Brains
121
we are no different from the split-brain patient; for he cannot imagine that either. (17) Thus, I claim, where S is the split-brain subject, the following are true: S has an experience of ‘pen’; S has an experience of ‘knife’; S does not have an experience of ‘pen knife’; S can be aware via introspection that he is having an experience of ‘pen’; S can be aware via introspection that he is having an experience of ‘knife’; S cannot be aware via introspection that he is having an experience of ‘pen knife’ (for S has no such experience); S cannot be aware via introspection (in a single act) that he is both having an experience of ‘pen’ and an experience of ‘knife’. If this is correct, then there is no special mystery about the mental lives of split-brain patients. 5.4 Disunified Access Consciousness (18) The fourth hypothesis I listed earlier, (d), has it that split-brain subjects have a unified phenomenal consciousness and a disunified access consciousness.3 This needs some explanation. Consider the case of blindsight. People with blindsight have large blind areas or scotoma in their visual fields due to brain damage in the postgeniculate region (typically the occipital cortex), and yet, under certain circumstances, they can issue accurate statements with respect to the contents of those areas (see Weiskrantz 1986). For example, blindsight subjects can make accurate guesses
122
Chapter 5
with respect to such things as presence, position, orientation, and movement of visual stimuli. They can also guess correctly as to whether an X is present rather than an O, or vice versa. And some blindsight patients can even make accurate color judgments about the blind field (Weiskrantz 1990). It appears, then, that, given appropriate instructions, blindsight subjects can respond in a way that is significantly like normally sighted subjects with regard to a limited range of stimuli in the blind areas in their visual fields, without there being anything experiential or phenomenally conscious going on. Blindsight subjects, however, do not spontaneously issue any public reports about the contents of their blind fields. In each case, they respond only when they are forced to choose between certain alternative possibilities.4 Moreover, they cannot identify objects in their blind fields as falling into everyday categories; they cannot tell what is present except in rare cases (of the sort mentioned above). So, for example, a thirsty blindsight subject will fail to recognize a glass of water placed before him, and hence will fail to reach out for it. The result is that blindsight subjects are invariably “deeply disabled” (Weiskrantz 1990, p. 8). (19) Why should there be such failures in identification or recognition? The natural answer is that blindsight subjects lack phenomenal consciousness (see, e.g., Marcel 1986; Van Gulick 1989; Flanagan 1992). The function (or a function) of phenomenal consciousness is simply to enable creatures to use information represented in their brains in the guidance of rational action (as contrasted with guessing behavior). Blindsight subjects cannot use the information from their senses rationally in the way that the rest of us can. (20) The claim just made about the function (or a function) of phenomenal consciousness is sometimes rejected on the
Split Brains
123
grounds that it improperly transfers a function of “access consciousness” (Block 1995) to phenomenal consciousness. Access consciousness, according to Block, is a matter of a state’s having a conceptualized representational content, one that is available for verbal report and plays an appropriate role in reasoning (see Block 1995, p. 232). The blindsight patient who fails to reach for a glass of water in his blind field lacks both sorts of consciousness. Block comments: There is an obvious explanation of why the patient doesn’t reach for the glass in terms of information about it not reaching the mechanisms of reasoning and rational control of speech and action, the machinery of A-consciousness (access consciousness). . . . A function of the mechanisms underlying A-consciousness is completely obvious. If information from the senses did not get to mechanisms of control and reasoning and of rational control of action and reporting, we would not be able to use our senses to guide our action and reporting. But it is a mistake to slide from a function of the machinery of A-consciousness to any function at all of P-consciousness. (p. 242)
So, it could well be that the absence of phenomenal consciousness is not a factor in the patient’s inaction. For all we know, it is empirically possible for access consciousness of the glass to be missing, while phenomenal consciousness is present; and, in this case, a thirsty subject will still not reach for the glass. This possibility is easy to ignore because access consciousness and phenomenal consciousness usually go hand in hand (and hence it is very easy to mistakenly identify them, according to Block). But it is a real possibility, certainly not one that can be ruled out a priori.5 (21) Consider now the earlier split-brain patient, S, who has the words ‘pen’ and ‘knife’ flashed up before him. The proposal with respect to S is that S has an experience just like that you or I would undergo in the same experimental
124
Chapter 5
conditions: S has an experience of ‘pen’ to the left of ‘knife’. But, given the commissurotomy, S does not undergo an access-conscious state, the content of which includes both ‘pen’ and ‘knife’. Using his right hemisphere, S undergoes an access-conscious state of ‘pen’ but not of ‘knife’. Using his left hemisphere, S undergoes an access-conscious state of ‘knife’ but not of ‘pen’. (22) This seems to me unconvincing. In the case of the thirsty blindsight subject, we can agree that there is no access consciousness with respect to the glass. The subject has no state that conceptually represents to him that a glass of water is present on the basis of the information in the light striking his eyes, even though he certainly has the pertinent concepts at his disposal (he can recognize glasses of water placed in his normal field, for example). But why is this? Why doesn’t information about the glass get to the cognitive centers, the loci of belief and reasoning? Why is access consciousness missing? That too calls for explanation. The obvious, commonsense answer surely is that phenomenal consciousness is absent. The patient has no visual experiences with respect to the blind field. There is nothing it is like for him as he stares at the glass. That’s why he doesn’t conceptually represent (or believe) that there is a glass of water present, and that, in turn, is why he doesn’t reach for it. (23) Intuitively, basic visual experiences are nonconceptual states. They do not demand that their subjects have concepts for what they represent. The visual sensations involved in seeing a rotten egg, for example, do not require that one believe it to be an egg, think of it as rotten, or even have any idea of what one is seeing at all. Visual states like these form the basis for possible conceptual responses, but they are not themselves conceptual.6 When they are absent—when there
Split Brains
125
is no visual phenomenology—there is nothing for the beliefforming processes to go on about what is in the field of view. So, no visual recognition occurs.7 (24) Perhaps Block would deny that it really is obvious that the blindsight patient does not conceptually represent that the glass of water is present because he has no pertinent visual experience. But it certainly seems to be the obvious response. This is not to say that it is an a priori truth or that it could not possibly be mistaken. The point is simply that to deny it would be very counterintuitive. My suggestion, then, is that access consciousness is missing in the patient because phenomenal consciousness is missing too.8 (25) Likewise in the case of split-brain subjects. Surely, the most straightforward explanation as to why the split-brain patient S has no access consciousness of ‘pen’ next to ‘knife’ is that he has no visual experience of the one design to the left of the other in his visual field. He has an experience of ‘pen’ and, on this basis, he undergoes a cognitive state representing ‘pen’. He also has an experience of ‘knife’ and, on this basis, he undergoes a cognitive state representing ‘knife’. But he does not experience the two words together. That’s why access consciousness of both is missing. (26) Those who take the opposing view seem motivated largely by the belief that disunity in phenomenal consciousnesss is impossible and perhaps even incoherent (Bayne and Chalmers 2003). However, as I have already argued in response to Nagel, there is no difficulty in imagining the mental life of a split-brain patient, under the phenomenal disunity assumption. So, the hypothesis of a unified phenomenal consciousness and a disunified access consciousness is neither intuitively plausible nor, so far as I can see, well motivated.
126
Chapter 5
5.5 Disunified Phenomenal Consciousness: Two Alternatives (27) We are left, then, with two alternatives: that split-brain patients are single persons who undergo two separate streams of consciousness that remain two from the time of the commissurotomy (Parfit 1984), or, more cautiously, that split-brain subjects are single persons whose phenomenal consciousness is briefly split into two under certain special experimental conditions, but whose consciousness at other times is unified (Marks 1980). The major difficulty faced by the former hypothesis, which is the more popular of the two among neuropsychologists, is that, except under the specified experimental controls, there is nothing unusual about the behavior of split-brain subjects. Their behavior is generally just as integrated as yours or mine. What leads to the supposition that split-brain patients have a disunified consciousness is their failure to behave in an integrated, coherent way in certain, special experimental situations. But if behavior is the evidence on which the hypothesis of disunity rests, then the fact that split-brain patients behave in an integrated way at other times supports the hypothesis that their consciousness is generally unified. (28) Perhaps it will be replied that once the hemispheres are divided, they function independently from one another as two separate units. Thus, suppose that ‘pen knife’ is left on the screen long enough to allow eye movements. Given that the hemispheres are divided, there are two separate neural pathways, and two representations of ‘pen knife’, one in each hemisphere even though there is nothing out of the ordinary in the behavior of the subject. But if there are here two separate representations of ‘pen knife’, then surely
Split Brains
127
there is a disunified consciousness. Generalizing, once the commissurotomy has been performed, there is always a disunified or split consciousness. (29) This is too quick. In the case that split-brain patients are presented with ‘pen knife’ on the screen and eye movements are allowed, the behavior is exactly the same as normals. They say that they saw ‘pen knife’, and they pick out a penknife with either their left or their right hands. This is prima facie evidence of a unified consciousness. The difference is at the level of neural processing. There are two pathways, in the split-brain patient whose eyes scan both ‘pen’ and ‘knife’, each of which would generate an experience of ‘pen knife’, were the other absent. There is, I suggest, a single experience in this case with a neurological realization or constitution that is partly redundant and that differs from the neurological realization or constitution of the experience of ‘pen knife’ in normal subjects. (30) It might be objected that a single experience cannot have as its physical basis neural events in the left and right hemispheres that are themselves causally unrelated. But why not? Consider the following example. Two movie projectors each project an image onto a screen at time t. Only a single image is present on the screen at t, since identical slides are in the projectors and they are aimed at exactly the same part of the screen. There are two projections but only one image. One projection is redundant. Each projection on its own suffices for the screen image. Alternatively, consider the case in which I am in a restaurant, and, being anxious to leave, I signal the waiter by raising both hands in the air and waving them. The event of my signaling the waiter is constituted by both the event of my waving my left hand and the event of my waving my right
128
Chapter 5
hand. Again, there is redundancy: one signaling and two hand wavings, each of which would have sufficed for signaling the waiter without the other. There seems no obvious reason why nature should not have made us so that, in certain circumstances, there is redundancy at the neural level in the generation of perceptual experience. After all, it is well known that the human brain has a neurological structure that is highly redundant anyway. Why not also here? (31) The conclusion I draw is that the final hypothesis is the most plausible: split-brain subjects are single persons whose consciousness is unified except in certain very special experimental situations. On those occasions, their stream of consciousness splits into two, which rejoin again once the experimental controls are removed—just as a river sometimes splits into two separate channels around islands, channels that merge again afterward. (32) There is one further point worth noting here. Some interesting experimental results (Trevarthen 1970) seem to show that split-brain patients, with the experimental controls in place, do nonetheless experience both halves of the visual field together at least to the following extent: they can judge accurately, on the basis of experience, whether two dots, one on each side of the fixation point, are moving together to the left or the right, or in opposite directions toward the fixation point. This has led some psychologists to question whether split-brain subjects have a divided consciousness at all. (33) These results present an additional serious problem for the hypothesis that split-brain subjects, after the commissurotomy, always have a divided consciousness. There is no difficulty, however, for the weaker hypothesis I am endorsing.
Split Brains
129
For, given that hypothesis, the obvious explanation is that, even under the usual experimental conditions for split brain patients, consciousness is not always divided. Standardly, as in the ‘pen knife’ case, there are two streams of consciousness. But for some perceptual inputs involving both sides of the visual field, a single experience is generated, just as it would be for a normal subject. (34) I turn in the final section to some further facts about split-brain patients that offer further support for my overall view of phenomenal unity. 5.6 The Nontransitivity of Phenomenal Unity (35) Once the corpus callosum is cut, the two hemispheres are not wholly divorced from one another; for the subcortical pathways still link the two. For example, if a pornographic picture is presented only to the right hemisphere, the subject reports feeling differently. “That’s quite a machine you’ve got there,” one split-brain patient remarked. Since verbal responses are controlled by the left hemisphere, information about the picture is evidently getting there. In another experiment, the subject saw, with his right hemisphere only, a picture of a frightening scene of a fire. Afterward, he commented, “I don’t really know what I saw; I think just a white flash. Maybe some trees, red trees like in the fall. I don’t know why, but I feel kind of scared. I feel jumpy. I don’t like this room, or maybe it’s you guys getting me nervous.” Again, what seems to have happened is that the emotion triggered by the right hemisphere had an effect, via the brainstem, on the verbal left hemisphere. The subcortical pathways in the brainstem also are responsible for the experience of touch around the neck and on the head. For example, if a split-brain patient is asked to
130
Chapter 5
say where a pin is gently pricking him on his neck or face, he will report its location accurately. If asked to touch his left forefinger to the relevant spot after the pin has been removed, again he will do so accurately. Here, the splitbrain patient’s behavior is just the same as that of a normal subject. And just as the verbal and nonverbal reponses of the normal subject are evidence for the experience of a pin prick in a certain location, so too are those of the split-brain subject. (36) Imagine now that as the neck of the split-brain subject, S, is pricked, he is presented with a red screen to the left, which he touches with his left forefinger, and a green screen on the right, which he touches with his right forefinger. S has an experience of his left forefinger together with a red surface. He also experiences a connection between that forefinger and the rest of his hand and arm; and he experiences his arm as connected (via part of his upper torso) to his neck, in which he experiences the prick. The same is true for S’s right forefinger, except that now the relevant surface is the green one. S thus experiences the redness of the surface and the pricking of the pin together. They are phenomenally unified in his experience. Likewise, S experiences the greenness of the other surface and the pricking of the pin together. They also are phenomenally unified in his experience. But redness and greenness are not experienced together. They are not phenomenally unified. Accordingly, phenomenal unity is not transitive: there are cases in which A is unified with B, B is unified with C, but A is not unified with C.9 How is this to be accounted for? (37) Within the metaphysical framework elaborated in the last four chapters, the explanation is straightforward. S has two multimodal experiences, E1 and E2. E1 represents the
Split Brains
131
pinprick in S’s neck, his left arm, fingers, and the surface his left forefinger is touching. E2 represents the pinprick in S’s neck, his right arm, fingers, and the surface the right forefinger is touching. The pricking is phenomenally unified with redness by their entering into the same phenomenal content—the phenomenal content of E1. The pricking is phenomenally unified with greenness in like manner, but this time the common content is the phenomenal content of E2. Since S has no experience whose phenomenal content has entering into it both greenness and redness, the two colors are not phenomenally unified. There is thus no more mystery attaching to the nontransitivity of phenomenal unity than there is to the nontransitivity of the relation of entering into the same thought content. Just as I can think that Ann loves Paul and also think that Paul is a neighbor of Raoul without having any thought into whose content Ann and Raoul enter, so a split-brain patient can experience A unified with B and also experience B unified with C without his experiencing A and C together. (38) It is not easy to see how the nontransitivity of the phenomenal unity relation is to be explained on alternative accounts. Those who, in opposition to the view I have been defending, think of unity as a relation between experiences will apparently have to say that nontransitivity is a primitive feature of the relation. But brute facts such as this are surely to be avoided wherever possible. Alternatively, it might be argued that the case just adumbrated does not suffice to show nontransitivity on the grounds that there are actually two simultaneous token experiences of the pin prick in the neck. One of these experiences is unified with the experience of a green surface and the other with the experience of a red one.
132
Chapter 5
The biggest difficulty here, leaving aside the point that unity, or so I have argued, is not a relation between experiences at all, is that there is no more reason to postulate two token, phenomenally identical experiences of the relevant region of the neck of the split-brain subject than there is to make such a postulation for any subject. Just as the latter postulation for normal minds is unmotivated, unnecessarily complex, and perhaps even incoherent (depending on how token experiences are individuated), so too is the former. Much better to take the imagined case at face value and give up what is, from the present perspective, a purely dogmatic adherence to transitivity.
6
Persons and Personal Identity
6.1 The Ego Theory and the Bundle Theory Quickly Summarized (1) In the last chapter, I gave some reasons for supposing that split-brain subjects are single persons, but I offered no theory of the nature of persons and personal identity. In this chapter, I propose such a theory. (2) The two best-known theories about the nature of persons are the ego theory and the bundle theory. The philosopher with whom the ego theory is most notably associated is Rene Descartes (1641); the most famous advocate of the bundle theory (at least in Western philosophy) is David Hume (1739). According to the ego theory, in its Cartesian form, persons are continuing, spiritual substances, whose essence is consciousness. What unifies different experiences I have at the same time, indeed what unifies my entire mental history, is the fact that all the relevant experiences are had by the continuing spiritual substance that is me. The ego theory thus grounds subject unity for experiences on sameness of spiritual substance. (3) The bundle theory draws on the observation that the experiences, thoughts, and other mental states of a single
134
Chapter 6
person stand in various causal relations to one another—for example, experiences cause introspective awareness of themselves as well as later memories—and thereby they are linked or bundled together. Each person, according to the bundle theory, is no more than a mental bundle. Not every mental bundle is a person, however. A person, for the bundle theorist, is an appropriately complex bundle, standardly one that includes “higher-order” beliefs, desires, and intentions connected to other mental states in the relevant ways. We may say that persons are the subjects of experiences; but this talk is misleading, according to the bundle theorist, at least if it is taken to imply that persons are substances. Persons are nothing over and above temporally extended clusters of mental events. And subject unity is no more than sameness of mental bundle. 6.2 Objections to the Ego Theory (4) It has been suggested (by Parfit 1984) that the ego theory, in its classical form, is incompatible with split-brain cases. According to Parfit, each split-brain subject is a single person, albeit one whose consciousness is divided. The ego theory, he claims, cannot allow such a division, for, as just noted, if the ego theory is true then what unifies a person’s experiences is simply the fact that they are undergone by the same spiritual substance. This is not fully convincing, however. The ego theory provides an account of subject unity for persons, not phenomenal unity. Split-brain patients, I have maintained, undergo experiences that are phenomenally disunified but not subject disunified. If, as I argued earlier, there is no difficulty in supposing that one and the same person undergoes distinct simultaneous experiences in the same sense-modality, then,
Persons and Personal Identity
135
if persons are spiritual substances, the same is true of spiritual substances. Of course, on the ego theory, persons are spiritual substances whose essence is consciousness, and Parfit would no doubt insist that creatures with an essence of this sort cannot have a divided consciousness without splitting into two themselves. However, there is no obvious contradiction in the idea that a single spiritual substance, whose essence is to undergo experiences, feelings, and conscious thoughts, has a phenomenally disunified consciousness in certain special situations while retaining a unified consciousness elsewhere. So, the claim that the ego theory in its classical form is shown to be mistaken by split-brain cases is unjustified, at least if one agrees with the view defended in chapter 5 of those cases. (5) The classical ego theory has other troubles. For if minds are spirits, it is very difficult to believe that the mental is ever causally efficacious with respect to the physical, given the abundant evidence for the causal closure of the physical world. Moreover, none of the historical arguments supports such metaphysical profligacy. So, Occam’s razor counts against the postulation of spiritual substances. (6) To this, the present-day ego theorist may retort that the classical view needs to be redressed in materialist clothing. Persons should be identified not with spiritual substances but rather with material substances, whose mental histories are unified by being histories of states of those substances. There are strong objections to any such revised proposal, however. (7) Consider first body transplants. While physicians cannot now transplant my brain into your body or vice versa, it
136
Chapter 6
is certainly conceivable that one day they will be able to perform such an operation. And if they do, then surely the right thing to say is that, once the operation is over, I will have your body. For the person speaking with your voice will have my memories, my character traits, and my psychological dispositions. One familiar way of making this point more vivid is to suppose that after a double switch in which my brain is put into your body and yours is put into mine, you get to choose which of the two people afterward will be tortured and which rewarded. Leaving to one side moral considerations that may influence your decision, unless you are a masochist or you like me more than you like yourself, you will surely choose that the person now with your body is to be tortured. For that person is no longer you. But if there can be the same
Persons and Personal Identity
137
live human body at two different times without the same person, then personal identity is not secured by identity of body. (8) Another reason not to adopt the view that persons are material substances is provided by the phenomenon of multiple personality disorder, discussed briefly in chapter 5. This phenomenon undermines not only the view that persons are the same as bodies but also the alternative materialist view that persons are the same as brains. For where there is a multiple personality disorder, there is one brain and one body but multiple persons. Consider, for example, the following case of Rene, a young woman who, as a child, was beaten, burned, and sexually abused by her parents, as described in Confer and Ables (1983): Rene was a bewildered and frightened woman. She was continually preoccupied with multiple experiences of which she could make no sense and over which she had no control. For example, she would find a number of skimpy, sexy bathing suits in her closet which her husband stated she insisted he buy for her, along with clothes that were too tight and too short. She had no memory of purchasing any of these. Similarly, bills would come in at the end of the month for car rentals and air travels she knew nothing of. Even worse, she would awaken on occasion to find herself in a strange motel and town with no knowledge of where she was or how she got there. . . . (p. 51)
Rene, we are told, had several alternate personalities. One of these was Stella. This . . . alternative was sultry and seductive. She apparently knew how to please others and spent her time doing this. For example, she pleased men by “taking them to paradise.” Frequently, she took . . . trips to other cities where she engaged in sexual liaisons with men. Rene would then emerge, awakening in a strange room with a strange man and feel horrified. (p. 53)
138
Chapter 6
Stella was impulsive and inattentive to the consequences of her actions. . . . She would charge hundreds of dollars of clothing or go on a trip to Mexico at a moment’s notice. . . . She reported watching behind the porch on Easter of Rene’s eleventh year when her father coaxed Rene into the house and bloodily raped her. . . . She described herself as Rene’s best friend. (p. 54)
(9) Another multiple personality case, in some ways even more clearcut, is that of Mary Reynolds (1793–1854), as described by Sutcliffe and Jones (1962) (and noted in Marks 1980): Her disorder was first noticed at 18 (1811). Before her alterations, she was described as a well-educated woman, of dull and melancholy temperament, living in the wilds of Pennsylvania. Her personality changed following a long and profound sleep. She awoke disoriented, no longer able to recognize relatives. . . . Previously reserved, taciturn and timid, she was now friendly, merry, and adventurous with a new interest in the outdoors. There was no regaining of self-reference memories or reestablishing of old personal relationships in “the second state.” . . . After five weeks in State 2, on this first occasion, Miss R. returned to her old state (State 1), following a further profound sleep. Now, in State 1, there was no memory for the intervening State 2 period. Alternations between these two mutually amnesic phases went on for 15/16 years. Memory was continuous within each of the phases.
Intuitively, in both of the above cases, there are two different persons, each with her own, separate mental history. Once again, the ego theory, in its materialist form, is in trouble. 6.3 Objections to the Bundle Theory (10) It may appear that the case of multiple personality disorder fits very nicely with the bundle theory. Rene is really several persons, it may be claimed, because she has several
Persons and Personal Identity
139
internally unified and coherent psychological histories, each of which is incompatible with the others. As Rene, she is not able to recognize the motel she is in, and she doesn’t believe that the bathing suits she finds in the drawers of her house are hers. As Stella, she is able to recognize the motel and she does believe that the bathing suits belong to her. As Rene, she has no first-person memories about herself as Stella, but she can remember earlier states of herself as Rene and she can be aware, via introspection, of what she (Rene) is thinking and feeling. Likewise for Stella. To explain the behavior of Rene, we appeal to one set of attitudes; to explain the behavior of Stella, we appeal to another. Evidently, there are here two relatively constant, internally coherent structures of propositional attitudes. Thus, if persons are just psychological bundles, there are two persons. (11) Corresponding points apply to the case of Mary Reynolds. For example, in state 1, Mary R. is able to recognize her parents, and in so doing she believes them to be her parents. In state 2, Mary R. is not able to recognize them and she does not believe them to be her parents. In state 2, Mary R. has no memories about herself in state 1 though she can remember her earlier state 2 states of herself, and vice versa. Again, two relatively fixed, internal consistent frameworks of propositional attitudes and, according to the bundle theory, two persons. (12) Persons, however, cannot just be bundles of experiences, beliefs, desires, memories, and so on. For one thing, on the view I developed in previous chapters, there are no individual experiences (pains, itches, visual experiences, feelings of anger, etc.) to enter into such bundles. At the phenomenal level, there are simply the streams of consciousness that come and go, one after another, as the days go by.
140
Chapter 6
Much more importantly, whatever else persons are, they are the subjects of consciousness and action. As Thomas Reid remarked in 1788, “I am not action, I am not feeling; I am something which thinks and acts and feels.” The bundle theorist says that this is just talk, of no real metaphysical significance. But it is surely very deeply embedded in how we ordinarily think of ourselves. The truth in the bundle theory, I suggest, is this: where there are two incompatible mental bundles, there are two persons. Consistent with this claim, we can and should reject the metaphysical thesis of the bundle theory with respect to the nature of persons. Let me explain. 6.4 A New Proposal (13) I am the subject of one stream of consciousness, followed by a period of unconsciousness, followed by another stream of consciousness, and so on. I have many long-standing beliefs, beliefs I have even when I am unconscious, for example, my belief that I am Michael Tye, that I live in the United States, that I grew up in the U.K., that my mother and my brother live there. I have long-standing desires too, for example, my desire to visit Turkey and my desire to drive a Ferrari. And today, while conscious, I can remember much of what happened yesterday, less of what happened to me the day before. I also have memories of my distant past, some of which are purely propositional and unconscious. In addition, there are many shorter-term beliefs and desires, beliefs about what I did earlier today and yesterday, for example, and desires about what to do in the next few minutes or hours. Some of these beliefs are manifest in my consciousness but others are not. The latter are beliefs I would still have even were I to become unconscious.
Persons and Personal Identity
141
My beliefs, desires, memories, and streams of consciousness form a coherent whole, against which my behavior can be explained. Let us call each such whole of sufficient complexity to include higher-order beliefs, desires, and intentions, a person-level psychological framework (or PF, for short). PFs, as I shall understand them, are not psychological types. They begin and end. They occur wherever the relevant persons are. Through time, they evolve or change gradually. Some new beliefs and desires are added, for example; others are dropped. Changes happen, moreover, in such a way that each mental state within a single PF causally depends on its immediate predecessors. Changes in PFs, thus, are not the result of the labors of some meddling demon who has decided to create a succession of mental states that is modeled on those of typical human beings.1 In the case of Mary R., there is no single PF. Mary R. has two interconnected and relatively stable frameworks or bundles of beliefs, desires, and memories, which in conjunction with the contents of the relevant sequential streams of consciousness explain her behavior. For example, if we ask why Mary R., in state 2, does not interact with her parents as if they are her parents, why, for example, she does not call them ‘Mother’ and ‘Father’, we have to suppose that she doesn’t believe that they are her parents. But in state 1, it is clear that she does have this belief. The natural, obvious explanation of this and a myriad of other such facts is that she is two persons. Each person is the subject of the psychological states making up a single, appropriately complex, belief/desire/memory/conscious stream of experience bundle or PF (and thereby each person is the subject of a single PF as a whole). With each different PF, there is a different person.
142
Chapter 6
(14) PFs, let me repeat, are composed of psychological tokens. I might have somewhere else in the universe a physical duplicate causally unconnected to me, a duplicate who lives on a Twin planet to Earth. However similar my twin’s PF is to mine, his PF is made up of different psychological tokens. There are, thus, two PFs, one for my twin and one for me, and correspondingly two persons. (15) Each person is the subject of the relevant PF or psychological bundle. We who are materialists hold that in actual fact the thing that thinks, feels, and so on is a certain material thing, most plausibly a brain. So, in actual fact each person is a brain. But it must be allowed that a single brain can be more than one person. That, I suggest, is what the case of multiple personality disorder shows. (16) This proposal may seem puzzling. How can one brain be two persons? Take the case of Mary Reynolds. The two persons are not identical, yet Mary R.’s brain supposedly is both persons. How can this be? The answer is that the ‘is’ here is not the ‘is’ of identity. Mary R.’s brain constitutes two persons without being identical with them. (17) Consider a lump of silver. At one time, in one physical state, it is a Roman denarius. Much later, having been melted down and reshaped, it is a British shilling. The ‘is’ in these two sentences is the ‘is’ of composition. The lump of silver, insofar as it is in one physical state (and setting), constitutes a denarius; insofar as it is in another, it constitutes a shilling. Likewise for Mary Reynolds except that in her case, the different physical states are cotemporaneous. Mary R.’s brain undergoes two global physical states, each of which physically realizes a PF. There is a single brain that insofar
Persons and Personal Identity
143
as it is one such state constitutes one person and insofar as it is in the other constitutes a second person. (18) Note that there is no difficulty in holding that a single entity E, insofar as it is an F, has property P, and insofar as it is a G, lacks P (where being an F is different from being a G). A brass ring, insofar as it is the ring Gustav gave to Emma on her twenty-first birthday, is valued greatly by Emma. That ring, insofar as it is a piece of brass, is not. A young man, insofar as he is a day trader of stocks, makes money irregularly. The same young man, insofar as he has a job as a bar tender in his evenings, makes money on a regular basis. (19) On my proposal, then, persons are neither egos nor bundles. They are the subjects of appropriately complex psychological bundles. In actual fact, I claim, these subjects are brains insofar as those brains are in the appropriate physical states (states sufficient for psychological states making up a single PF). But in some other (conceptually) possible worlds, persons are immaterial entities insofar as they are in the appropriate nonphysical states. Let us look next at various problem cases. 6.5 Problem cases (20) Consider again the case of a split-brain subject. I argued earlier that although, when the experimental controls are in place, there are two streams of consciousness, there is nonetheless a single person. This position is compatible with the current thesis. For even while her consciousness is divided, the split-brain patient retains a single set of longstanding beliefs and memories; and after the experiment is over, she is capable of remembering the experiences she had during the experiment and her behavioral responses. Just as a single PF can encompass gaps in consciousness, from one
144
Chapter 6
period of consciousness to the next, so it can encompass a consciousness that divides briefly and comes together again. In the latter case, later psychological states are causally connected to earlier ones in the PF, much as they are when consciousness is not divided. (21) Consider next the case of teletransportation. Suppose that a machine of the future can read my brain cells and make perfect duplicates of them instantaneously in another part of the universe. After the duplication, which takes place all in one go, a perfect replica of my brain is created elsewhere, harbored, we may suppose, in a duplicate body. The psychological states of both brains after teletransportation are causally dependent on the earlier psychological and physical states of my brain. How many persons are there in this case and which one is me? (22) Intuitively, after the teletransportation device has done its work, I still reside on earth. The same brain remains on Earth and immediately after teletransportation it is in the very same physical states it was before. Intuitively, what teletransportation does in this case is to create an additional person, a copy of me. This is why if I am told prior to transportation that afterward one of the two persons will be killed and that I must choose which is to survive, I will surely choose to have the teletransported person die, if what matters to me most is that I survive. If you have any doubts about these claims, consider other cases not having to do with personal identity. Suppose that the Mona Lisa is placed inside the teletransporter and a molecular copy is made elsewhere. This process does not move the Mona Lisa to a new location. It creates a duplicate of the Mona Lisa. Similarly, in the case of a favorite chair of Louis XVI, the teletransported chair is not the chair in which King
Persons and Personal Identity
145
Louis sat. It is a copy of that chair. The case of persons is no different. (23) It may be objected that the second person cannot come into existence as teletransportation takes place. For, given the causal links, the second PF includes psychological states that were tokened prior to teletransportation; and if Tye Copy comes into existence only with the teletransportation process then he cannot be the subject of the whole psychological bundle. My reply is that the second PF begins with the creation of the new brain and body. Consider my long-standing firstperson beliefs up to the moment of teletransportation. Tye Copy does not believe what I believe in having these beliefs. To be sure, he believes that he is Michael Tye, that he grew up in the U.K., that his brother still lives there; but Tye Copy’s beliefs, unlike mine, are all false, since the concept I, as used by Tye Copy, refers to a different person from me. What he believes, therefore, cannot be just what I believe.
146
Chapter 6
Admittedly, his first-person beliefs are causally dependent on mine, and his narrow behavior, as it is associated with these beliefs, is just like mine. But his wide first-person behavior, both verbal and nonverbal, is different. His PF contains none of my long-standing (wide) first-person memories, beliefs, and desires. With teletransportation, then, there is a sudden and sharp psychological shift. Accordingly, Tye Copy’s PF is a successor PF created by the teletransportation process—a successor that initially copies my PF as much as possible consistent with the fact that a duplicate person has been created. (24) Suppose now that at the time of teletransportation, the original brain is destroyed just as the duplicate is created. Do I continue to exist albeit with a different brain in the new location? Or is there left in existence only an exact copy of me? My answer is that I no longer exist. One and the same person cannot be one material thing at one moment and another wholly different material thing at the next, any more than can one and the same car or mousetrap or tree or picture. This is not to say, of course, that one material thing cannot be physically type-identical with another. My mousetrap and yours may be physically indistinguishable, and thus yours may substitute for mine without any noticeable change. But even if your mousetrap substitutes for mine, that does not make it identical with mine. There are two mousetraps, however similar they may be. I am also not denying the obvious truth that material entities can change their parts through time. The point is that sudden, total destruction of all the matter composing an object destroys that object and with it whatever entity it wholly composes regardless of what happens subsequently.
Persons and Personal Identity
147
(25) Consider also the possibility of the teletransporter making two duplicates of my brain and body elsewhere and destroying the original brain and body as it does so. Which one is me? The right answer surely is neither. With two duplicates, I no longer exist. Suppose next that one of the duplicates is made a moment or two after the other. Intuitively, this makes no difference. Now suppose the case is as in (24): just one duplicate is made and the original brain and body are destroyed. If the view is taken that in this case I survive teletransportation, then since a second duplicate could be created a moment or two later, whether I am still alive immediately after teletransportation depends on whether subsequently the teletransporter makes another copy. And that, I suggest, is very strange indeed. (26) What, then, of the intuitive view that in the Star Trek television series persons survive relocation via the transporter beam? When Captain Kirk says, “Beam me up, Scotty,” it doesn’t occur to him that the person who materializes on the Enterprise won’t be the same person as the one who issued the command, and neither does the viewer conceive of the “transported” individual as a different person either. This seems to me correct to the extent that the transporter beam is conceived as somehow transporting the original molecules through space to a new location and reassembling them. After all, material things can be taken apart and put together again. But the teletransporter imagined above does not work in this way. It destroys the original molecules and replaces them with duplicates. Here, in my view, our intuitions go the other way. (27) Imagine next a range of cases in which the teletransporter destroys, and replaces with exact duplicates, a different proportion of cells in my brain and body (Parfit 1987).
148
Chapter 6
With all of my cells replaced, the case is the same as the one in (24), and I no longer exist. But what happens to me, if 10 percent is replaced, or 35 percent, or 70 percent? Is there a fact of the matter about which partial teletransportation destroys me? Clearly, my brain is not destroyed by the replacement of a small percentage of the original neurons any more than is my car destroyed by changing the tires or the battery. Equally clearly, if all the neurons are destroyed and replaced by teletransportation, the brain I was born with no longer exists. In the latter case, as just noted, I cease to exist too. Total cell replacement thus creates a new PF. Of course, the subject answers to the same name, and apparently has the same memories and the same beliefs. But there is a new subject, a duplicate of the original—someone whose (wide) first-person memories and beliefs are different from mine notwithstanding the psychological similarities. Intuitively, there is no fact of the matter about which replacement process destroys my original brain. Given that I do not exist in the case that a new brain is created with no parts in common with my original brain, and I do exist so long as my original brain exists, the natural view to take is that there is no fact of the matter as to which replacement destroys me. Once enough of the original neurons are replaced (and the originals simultaneously destroyed) a new brain is created and the resulting person is not me. (28) It may now be wondered what the proposed view has to say about the case of body transplant discussed earlier. Here the intuition is that putting my brain in your body and your brain in mine puts me in your body and you in my body. That intuition is not threatened by the position I am adopting. I am constituted by my brain (insofar as it is in the
Persons and Personal Identity
149
appropriate physical states) and you are constituted by yours. So, I switch with my brain. With this switch, the PF whose early stages are located inside my original body has its later stages located inside yours. (29) Here is another imaginary case due to David Wiggins (1967). Suppose that a person’s brain is divided into two, and the two halves are taken out of their original body and transplanted into two other bodies from which the original brains have been removed. After the operation, there are two persons who live separate lives. Derek Parfit (1987) says about this case: If I was about to divide, I should conclude that neither of the resulting people will be me. I will have ceased to exist. (p. 25)
This seems to me intuitively plausible. Moreover, there is theoretical reason to take such a position. Consider the two resulting persons. Which one is me? Picking one over the other here is clearly arbitrary: I am just
150
Chapter 6
as closely related to person 1 as I am to person 2. So, given that there are too many equally eligible candidates, either I am both persons after the operation or I am neither. I cannot be both persons after the operation, for it is a priori necessary that I am a single person. So, I am neither. What the operation does is to destroy me and to generate two new PFs, each with its own subject. Thus, two new people are created by the process of division and transplantation. Insofar as my original brain survives this process, it does so only as a scattered object. One-half of that scattered object composes one person and, via the appropriate physical states, supports one PF; the other composes another person and supports a second PF. (30) Perhaps it will be replied that the case is one in which the psychological attitudes of the two persons after the operation are continuous with those before. There is no sudden radical discontinuity in beliefs, desires, memories, and so on. But if this is so, then there are two PFs that share the same stages up until the operation. Initially these PFs are one. Once the brain has been split in two and the two halves transplanted, the PFs diverge in their stages. This reply effectively assumes that narrow psychological continuity entails sameness through time of PF and with it sameness of person. This I have already denied. Given that the division destroys me, my wide long-standing belief that I am Michael Tye, for example, is not a belief that is possessed by either of my successors. Since neither of these persons is me, the beliefs they would express shortly after the division via the production of (or assent to) the sentence “I am Michael Tye” have different truth-conditions from my belief, and thus neither of their beliefs is a long-standing belief at all. There is, then, a sudden, sharp discontinuity or
Persons and Personal Identity
151
change in (wide) first-person beliefs. My successors’ firstperson beliefs evidently belong to a different PF from that in which my first-person beliefs find their home. Likewise for first-person desires and memories. (31) The last case I want to consider is that of a person (let us call him ‘Antonio’) who, like Methuselah, lives a very, very long time . Antonio, with the passage of time, changes in many striking ways. At the end of his life, Antonio can no longer recall any of the events that took place in the first fifty years. His opinions have changed dramatically as he has aged. His character is nothing like the character he had in his youth. His goals for himself in his later years bear no resemblance to his goals when young. It is natural to say that, with all these changes, Antonio has become a different person. How can this be? (32) The answer, I suggest, is that at the end of his life, Antonio is not the subject of the same PF as he was in his youth. Antonio is, in important respects, similar to the individual who has multiple personality disorder. Just as the latter individual is really two or more persons whose behavior licenses the ascription of incompatible PFs, so too Antonio’s behavior late in his life is so at odds with his behavior in his younger years that it can only be supposed that different PFs are present early and late. With the different PFs, there are different persons. The changes in Antonio, both psychological and behavioral, are by and large gradual, not sudden and sharp, as when a new person emerges in a case of multiple personality disorder. Even so, once enough changes are in place, once the overall pattern of psychological states has altered sufficiently, the original PF no longer exists. A second PF has taken over. How much is ‘enough’? It’s vague. Our ordinary thought
152
Chapter 6
places the bar very high for a change of this sort. But evidently there is no sudden transition, any more than there is for the poor man who, by hoarding enough pennies, eventually becomes rich. (33) The case of Antonio may seem to create trouble for my earlier views on the unity of experience through time. In
Persons and Personal Identity
153
chapter 4, I said that direct phenomenal unity through time is a relation between experientially represented qualities— a relation that obtains if and only if the qualities experienced in one specious present are experienced as succeeding or continuing on from the qualities experienced in the immediately prior specious present. Since phenomenal unity requires subject unity, and in Antonio’s case it is vague when the second person emerges and the first ceases to exist, direct phenomenal unity through time must be vague too. That, it may be urged, makes no clear sense. (34) But why not? It seems clear that the property of entering into the same representational content admits of borderline cases, as does the property of entering into a representational content. If these properties are vague, then, on my view, phenomenal unity, whether it is at a time or through time, is vague too. Moreover, in Antonio’s case, there seems nothing obviously wrong-headed in the suggestion that there may be certain qualities such that it is indeterminate as to which person experiences them (or their succession), given the vagueness of the transition from the first to the second person. This indeterminacy means that properties of the type, experiencing quality Q (or the succession of Q by Q’), have borderline cases. (35) Some philosophers will not like my handling of the case of Antonio. They will say that there cannot be indeterminacy in whether the first person still exists or whether the second has taken over. Vagueness here requires vagueness in personal identity; and personal identity is always a black or white matter. There cannot be borderline cases. This, it seems to me, is not the intuitive view, but it would certainly be the reaction of adherents to the ego theory, in its classical form. There is also a famous argument due to Gareth
154
Chapter 6
Evans that may seem to support this position. In the last part of this chapter, I shall not say anything further about the ego theory, but I shall address both the general issue of whether identity can be vague in the context of Evans’s argument and its ramifications for vagueness in personal identity. 6.6 Vagueness in Personal Identity (36) Suppose that ‘a’ and ‘b’ are singular terms, and that ‘a b’ is a vague identity statement so that ‘a b’ is indefinite in truth-value. Then we have: (1) (a b). (1) ascribes to b the property of being indefinitely identical with a. This property may be expressed formally via the predicate ‘x ((x a))y’, where this abbreviates ‘y has the property of being an x such that it is indefinite whether x is identical with a’. So, (2) x ((x a)) b is also true. Now surely we have (3) ¬ (a a) and hence (4) ¬x ((x a)) a. By the principle that if object x and y differ in a property then they are not identical (the contrapositive of Leibniz’s Law, which states that if x and y are identical then they share all the same properties), from (2) and (4), (5) ¬(a b)
Persons and Personal Identity
155
follows. And (5), according to Evans, to whom we owe the argument, contradicts the initial assumption that ‘(a b)’ is true. So, for the case in which ‘a’ and ‘b’ are singular terms for persons, the conclusion to which we seem driven is that there cannot be vagueness in the identity of persons. (37) This argument has provoked extensive discussion. Let us grant for the moment that (1) is true. Does (2) follow from (1)? Some have thought not. David Lewis (1988), for example, compares this step in Evans’s argument to supposing that from (6) It is contingent whether the number of planets is 9 it is legitimate to infer (7) The number of planets is such that it is contingent whether it is 9. Since (7) evidently does not follow from (6), neither does (2) follow from (1), on the assumption that the operator ‘indefinitely’ or ‘it is indeterminate whether’ is analogous to the modal operator ‘it is contingent whether’. Let us suppose that as a counterpart to the notion of a rigid designator, we have the notion of a precise designator. Then, Lewis’s point can be put this way: Just as the inference from (6) to (7) goes wrong because ‘the number of planets’ is nonrigid, so too the inference from (1) to (2) is fallacious because ‘a’ is imprecise or vague. This reasoning is unconvincing. To begin with, we can all agree that some designators are vague. Suppose, for example, that it is indeterminate whether Jane S. or Mary W. is more beautiful than any other American woman. By some widely accepted criteria of beauty, Jane S. wins; under other widely accepted criteria, Mary W. is the winner. Then ‘the
156
Chapter 6
most beautiful American woman’ has no single determinate referent. So, we can all agree with Lewis that the inference from (1) to (2) is fallacious, if ‘a’ is a vague designator, that is, a designator that is such that it is indeterminate which object it picks out. But what if ‘a’ is a precise designator? Lewis assumes that there are no precise designators that designate vague objects (that is, designators that are such that it is determinate which vague objects they pick out). For he holds that there are no vague objects. (38) I take the opposing view. Common sense has it that the world contains clouds, mountains, deserts, and islands, for example, and these items certainly do not seem to be perfectly precise. Moreover, on the face of it, the imprecision of these items does not derive solely from the ways in which we think or speak about them any more than their existence does. We did not create Mount Everest by thinking or speaking about it; and intuitively neither did our thought or speech make its boundaries vague. Those who reject the thesis that the world contains vague objects typically insist that really things like mountains, deserts, and so on don’t exist. So, really, there are no things with fuzzy borders. As Lewis puts it: The reason why it’s vague where the outback begins is not that there’s this thing, the outback, with imprecise borders; rather there are many things, with different borders, and nobody has been fool enough to try to enforce a choice of one of them as the official referent of the word ‘outback’. (1986, p. 212)
On this view, there are lots of minimally differing precise aggregates of land molecules out there. When we use a term like ‘the outback’, there are many equally eligible candidates among these aggregates for the referent of the term. The aggregates themselves have a precise structure. What is
Persons and Personal Identity
157
vague is simply which aggregate the term picks out. And this vagueness, in turn, derives from the term’s meaning. Vagueness is thus a semantic phenomenon. Again this is not, I think, the intuitive view of the matter. Intuitively, there is no vagueness or indeterminacy in which entity, ‘Everest’, for example, denotes. It denotes a single mountain in the Himalayas, a bloody great mountain, indeed the highest mountain in the world. The indeterminacy resides in its referent. The referent is vague. There is no line that sharply divides the matter composing Everest from the matter outside it. Everest’s boundaries are fuzzy (Tye 1990). Many molecules are definitely inside Everest; and many are definitely outside. But some have an indefinite status: there is no objective, determinate fact of the matter about whether they are inside or outside.2 Notwithstanding its vagueness, Everest itself certainly exists, however. It was discovered. It can be photographed. People climb it regularly. People have died on it.3 Just as Everest has vague boundaries, so too intuitively do I. For when exactly did I begin, and when exactly will I end? And where exactly are my boundaries in space? If persons are not egos, then there are no definite answers to these questions. (39) To return to Evans’s argument: intuitively, there is nothing to bar ‘a’ from being a precise designator that picks out a vague object (‘Everest’ is such a designator, in my view). So, Lewis has not shown that there is anything wrong with the inference from (1) to (2), if the designators are precise.4 (40) Another possible response to Evans’s argument is to claim that there really are no such properties as the properties ascribed in (2) and (4). This strategy, however, does not really help. For although it is customary to state Leibniz’s
158
Chapter 6
Law with reference to properties, this is not strictly necessary. A nominalist, for example, might restate the law, without distorting its intuitive core, so that it asserts that any objects x and y are identical only if they satisfy all the same predicates. Given corresponding restatements of (2) and (4), the original challenge to Evans’s argument now collapses. (41) Another possible line of reply to the argument is to attack the unrestricted applicability of Leibniz’s Law, and with it the inference from (2) and (4) to (5). This seems ad hoc, however. For what could be more obvious than that if objects are identical then they have all the same properties? A more interesting response is to accept Leibniz’s Law but to argue that (2) and (4) do not attribute different properties to a. This response is offered by Jack Copeland (1995). He says: . . . the statement that a has the property of being determinately identical to a ascribes the same property to a as the statement that a has the property of being determinately identical to itself. It is not as though there are two different properties that a has, the property of being determinately self-identical and the property of being determinately identical to a. But b, of course, also has the property of being determinately self-identical. So, (4) [x ((x a))a, where ‘’ abbreviates ‘definitely’]5 does not attribute to a any property that b lacks. . . . The situation is the same in the case of (2) and (4). (4) states that a does not have a certain property; and indeed b does not have this property either. To hold that (2) and (4) are both true is not to say that b has a property which a lacks. (p. 88)
Prima facie, this is implausible. Consider the property of loving oneself, a property possessed by all narcissists and, let us suppose, by Paul in particular. Jane also loves Paul. So, Jane has the property of loving Paul. But the property of loving oneself is not the same as the property of loving Paul. If it were, then Jane, in loving Paul, would love herself;
Persons and Personal Identity
159
further, all narcissists would love Paul. But many do not; indeed, many have not even heard of Paul. Moreover, the property of loving oneself has instances in possible worlds in which Paul does not even exist. So, there are two different properties here. Likewise, I suggest, in the case of the property of being determinately self-identical and being determinately identical with a. No good reason has been given for denying that (2) and (4) really do attribute different properties to a. (42) A still further reply to Evans’s argument is that the conclusion (5) doesn’t contradict the initial assumption (1). The obvious counterreply to this is that since (5) has been established in the course of a proof, it is permissible to infer (8) ¬ (a b). just as once P is established in a proof, □P may be inferred on any later line. Since (1) is equivalent to (1a) ¬ (a b) & ¬ ¬ (a b), from (1), (9) ¬ ¬ (a b) follows. And (9) formally contradicts (8). (43) It must be admitted that within a framework of fuzzy logic of the sort proposed by Zadeh (1965), with an infinity of truth-values in the range of 0 to 1, the inference from (5) to (8) is invalid, even given that this occurs in the context of a proof of (5). For if the value of (a b) is equal to 1, the value of ¬ (a b) is less than 1 but greater than 0, and thus the value of ¬ (a b) is equal to 0. Since the derived formula, (8), has a lower value than the formula from which it is derived, (5), the inference is invalid.6
160
Chapter 6
To offer this reply, however, is already to adopt a framework within which the inference from (1) and (3) to (5) fails to go through. For, as just noted, within fuzzy logic, where (a b) takes the value 1, the value of ¬ (a b) is less than 1. But, given the very strong, intuitive plausibility of the reasoning from (1) and (3) to (5), once it is properly elucidated, the natural conclusion to draw is that any fuzzy logic that classifies the reasoning as invalid is unsatisfactory. (44) Perhaps it will now be charged that Evans’s supposed proof has some very counterintuitive results and for this reason is suspect. Consider, for example, the identity statement (10) Princeton Princeton borough. According to David Lewis, (10) is vague or indefinite, since “it is unsettled whether the name ‘Princeton’ denotes just the Borough, the Borough plus the surrounding Township, or one of countless larger regions” (1988, p. 128). Does this not fly in the face of Evans’s proof? No, it does not. As Lewis understands the term ‘Princeton’, it is not a precise designator: there is no single object that it determinately denotes. Nothing in Evans’s proof is incompatible with there being indeterminate identity statements in which vague designators figure. (45) Here is a second possible problem case for Evans’s argument based on some remarks of Derek Parfit (1984). There is a club—called ‘Black’s’, let us suppose—which is created at some time t and thereafter has a club-house, a membership list, and a set of rules. Black’s is never formally disbanded, but through time its members meet more and more infrequently and the club-house becomes run down. There are no meetings for several years. Twelve years later, however, a few of the original members get together with
Persons and Personal Identity
161
some new people and start to meet once more in the same building (now redecorated). The club they belong to at this later date, t (t 12), has the same name as Black’s. In what follows, to avoid confusion, let us capitalize the name for the club at t. On Parfit’s view, the statement (11) Black’s BLACK’S is indefinite. Moreover, the indefiniteness, we are told, is not an epistemic matter, since there is no further information that would settle the matter one way or the other. (46) Let us look at this case more closely. If the old members of Black’s who meet again at t intend to create a new club by their later meeting, then the most plausible view is that Black’s and BLACK’S have radically different origins: Black’s began at t, BLACK’S at t. So, the clubs are not identical and (11) is false. If the old members intend at t to be resurrecting the old club, then, given the other facts—the same name, the same place, some of the same members—the natural view is that BLACK’S is the same club as Black’s. The old club was merely disbanded for a while. Under this scenario, (11) is true. What if the people meeting at t have no relevant intentions with respect to the relationship of the old club to the new one? Then the situation is such that the name ‘BLACK’S’ does not pick out a single club with a single origin. For it is now left open not only whether ‘BLACK’S’ picks out something that began when they started meeting again but also whether it picks out something that began twelve years earlier. That much indeterminacy in origin means that no club has been individuated by uses of ‘BLACK’S’. This is not to say that clubs must have sharp origins, but rather
162
Chapter 6
that there are limits on the indeterminacy of their origins, limits consonant with their admittedly vague persistence conditions. Since the origin of a club, like that of a clock or a human being, is essential to its identity, the case now is one in which no club has been singled out. There are radically different, equally good answers to the question “What is the origin of the club called ‘BLACK’S’?” So, there is no one club that the name ‘BLACK’S’ definitely designates.7 (47) Thus, the case does not exhibit any vagueness in identity. The vagueness, on the last interpretation, pertains to what a certain name denotes.8 (11), on this interpretation, is indeed indefinite, but its indefiniteness does not undermine or threaten Evans’s argument.9 One can, of course, stipulate that the name ‘BLACK’S’ definitely denotes a club-stage, say, if one prefers. But then (11) again is straightforwardly false. Even if BLACK’S is a club-stage, Black’s is not. (48) Consider finally the case of Antonio again. If there is no definite moment at which the first person (call him ‘Tony’) ceases to exist and there is no definite moment at which the second person (call him ‘Anthony’) emerges, then Tony and Anthony have vague boundaries. Even so, Tony has properties that Anthony lacks. This is a consequence of the different PFs associated with each. So, by Leibniz’s Law, Tony and Anthony are not identical. What is vague or indeterminate is where the temporal boundaries of Tony and Anthony lie.10 (49) I conclude that Evans’s argument stands. But what exactly does it prove? Since it shows that there can be no true statements of the same type as (1), where the component designators are precise designators for vague objects, it proves that there cannot be satisfiers for wz ((w is identical to z)) x, y. Further, since the argument extends straight-
Persons and Personal Identity
163
forwardly to the case of precise designators for precise objects, it proves that the identity relation is sharp. (50) Evans, however, does not prove that there cannot be vague identity statements. One possible example is (11) above, given one possible further elucidation of the example. Nor does Evans’s argument show that there cannot be vague objects in the sense of objects with vague boundaries (that is, boundaries that are capable of being made more precise). The world is full of such objects, in my view, and persons are among them.
Appendix: Representationalism
You are standing before a tapestry in an art gallery. As you take in the rich and varied colors of the cloth, you are told to pay close attention to your visual experience and its phenomenology. What do you do? The representationalist says that you attend closely to the tapestry and details in it.1 You are aware of something outside you—the tapestry—and of various qualities that you experience as being qualities of parts of the tapestry, and by being aware of these things, you are aware of what it is like for you subjectively or phenomenally. But your awareness of what it is like, of the phenomenology of your experience, is not de re awareness of the experience or its qualities.2 It is de dicto awareness that you have an experience with a certain phenomenal character or “feel.” Here is another way to put these points. When you are told to attend closely to your visual experience, what you actually do is to attend closely to the tapestry and the various ways it, or parts of it, look to you. Ways things look to people are typically expressed by predicates (as in ‘looks red’, ‘looks square’, ‘looks close’), and predicates express qualities—in this case, qualities represented by the relevant experiences of those people, qualities such that if the things
166
Appendix
seen have them, the experiences are veridical or accurate. Change the qualities “out there,” more specifically, the qualities that are the ways the tapestry looks, and necessarily the “feel” of your experience changes. What is true for vision is true for the other senses. Attending to the phenomenology of a perceptual experience, to its felt character, is a matter of attending to the ways things look, smell, taste, sound, or feel by touch. In the case of bodily sensations, the object of your attention is the way a certain part of your body feels.3 More generally, attention to phenomenal character is a matter of attention to the ways things other than the experience seem, that is, to qualities that are not qualities of experiences. Change any of the qualities that are the various ways things look, smell, sound, and so on and necessarily the phenomenal character of the experience changes. Why should this be? The answer the strong representationalist proposes is that phenomenal character is identical with a certain sort of representational content into which the relevant qualities enter. Some representationalists take a weaker stand. They say merely that once the qualities that are directly experienced are fixed, the phenomenal character is fixed. We have, then, initially, two representationalist positions: Strong representationalism: Phenomenal character is one and the same as representational content that meets certain further conditions. Weak representationalism: Phenomenal character supervenes on representational content that meets certain further conditions (so that necessarily any two states that are alike with respect to the relevant representational content are alike phenomenally).
Representationalism
167
It should be obvious why the qualifiers ‘meets certain further conditions’ and ‘relevant’ are added. Not all states with representational content have any “feel” or phenomenal character at all. Consider, for example, unconscious beliefs or subpersonal representational states involved in early vision representing light intensity or zero-crossings. Reductive strong representationalism is the view that both that the representational content with which phenomenal character is identical can be spelled out in physical or functional terms, and that the further conditions on that content can be spelled out similarly. Nonreductive strong representationalism is the view that either aspects of the content itself or aspects of the further conditions on the content are neither physical nor functional. On this view, phenomenal character is identified with representational content, but the content itself, or conditions on it, are irreducibly phenomenal. Corresponding reductive and nonreductive positions are possible with respect to weak representationalism. Representationalism admits further of wide or narrow contents. Externalist representationalism is the thesis that microphysical duplicates can differ with respect to the relevant representational contents of some of their internal states. On this view, differently situated duplicates or duplicates with different histories can differ phenomenally. Internalist representationalism denies this. According to the internalist, microphysical duplicates must be alike with respect to the appropriate representational contents of their internal states. There is also room for disagreement about whether the contents are Fregean or not. For the Fregean representationalist, the pertinent representational contents are individuated at least in part by conceptual modes of presentation. For the
168
Appendix
non-Fregean, the contents are nonconceptual. Non-Fregean contents may be Millian (after John Stuart Mill), individuated exclusively by worldly entities such as concrete objects and properties, or hybrid, individuated in part by nonconceptual, sensory modes of presentation as well as worldy entities (paradigmatically properties).4 It is worth emphasizing that the Fregean representationalist can allow that the concepts whose modes of presentation are partly individuative of the relevant contents need not be concepts the subject of the experiences has. Thus, in another sense of nonconceptual content (under which the content of state S of person P is nonconceptual if and only if P need not possess any of the concepts used by theorists to state the accuracy conditions for S), Fregean representationalism is compatible with the thesis that the sort of content relevant to phenomenal character is nonconceptual content. Philosophers who are representationalists may or may not be reductionists about phenomenal concepts. Those who are see the representationalist story as analyzing the contents of those concepts, as spelling out in a priori terms what it is to be in a state with so-and-so phenomenal “feel” and more generally what it is for a state to have a phenomenal “feel.” Those who are not reductionists here think of the representationalist theory as offering the best explanation of various pieces of data about the phenomenal (including the datum with which this appendix began) without itself being a conceptual truth. My current view is a form of strong, reductive, Millian, (qualifiedly) externalist representationalism; but I am not a reductionist about phenomenal concepts.5 I claim further that only qualities enter into the pertinent contents. Concrete individuals play no role as far as phenomenology goes, for hallucinatory experiences have a subjective “feel” to them
Representationalism
169
and in cases of hallucination there are no appropriate concrete individuals. I also claim that the further conditions the representational contents must meet are wholly functional. My position is a Millian one for two reasons. First, as explained in detail elsewhere (Tye 2000) and as commented on in various places in this book, experiences have nonconceptual representational contents. This, as yet, does not secure either Millianism or a hybrid position without further argument that these contents are nonconceptual in the stronger sense distinguished above. Second, Millianism is the position that best fits our ordinary phenomenal ways of talking (and thinking). This point deserves further elaboration, especially since I have wavered on it in my previous writing.6 I shall use the case of visual perception for the purposes of illustration. I take it that visual phenomenology is captured linguistically in everyday contexts by one kind of ordinary ‘looks’ talk. If two things, X and Y, look the same, in the phenomenal sense of ‘looks’, then the visual experiences of X and Y are alike in their phenomenal character; and if X and Y differ phenomenally, then the visual experiences differ in their phenomenal character. Some ‘looks’ talk is epistemic, as in ‘It looks as if it is about to rain’ and in ‘The wood looks to be pine’; and some is comparative, as in ‘That looks like a dog.’ Where phenomenal ‘looks’ talk is in play, the term ‘looks’ is always followed by a term for a quality of which the given subject is directly aware in undergoing the given visual experience. Thus, ‘That looks feline’ is not an example of a use of the term ‘looks’ in the phenomenal sense. Cats and twin-cats (creatures that look just like cats but are different biologically) look the same phenomenally. There is no telling a cat from a twin-cat, going by the phenomenal look alone. I can
170
Appendix
be aware that something is a cat by the way it looks phenomenally, but the quality of being a cat is not a quality of which I am directly aware. In his (1977), Frank Jackson gave clear, compelling arguments for the view that phenomenal ‘looks’ sentences are not analyzable in terms of sentences using the term ‘looks’ in its comparative or epistemic senses. These arguments, I might add, do not entail that a sharp distinction need always be drawn between ‘looks F’ and ‘looks to be F’.7 In some cases, there is such a distinction: ‘looks Smith’, for example, is incoherent while ‘looks to be Smith’ makes sense, since ‘Smith’ is a name for an individual and the ‘looks F’ location requires that ‘F’ take terms for qualities as its substitution instances. But ‘F’ here need not always be a predicate like ‘red’; it can also be an abstract singular term for a visually presented quality, as, for example, in the case of ‘the color of most fire-engines’. If a shirt looks red to me, then it looks the color of most fire-engines to me. That should be uncontroversial. But why is this the case? The answer surely is that red is the color of most fire-engines, and the shirt, in looking red, looks to have the property of redness or being red. The substitution of ‘the color of most fire-engines’ for ‘red’ here is safe, since the context is a phenomenal one, and such contexts permit substitutions of terms for the same quality.8 How the quality is described or conceived does not matter. Note that red is not the same as the quality of having the color of most fire-engines. The latter quality is a quality possessed by most fire-engines in a possible world in which fire-engines are painted blue. The former is not. ‘The color of most fire-engines’ is a nonrigid designator that picks out redness in the actual world, but other colors in other worlds. ‘Having the color of most fire-engines’ is a rigid designator
Representationalism
171
that picks out the same quality in all possible worlds, a quality different from redness. This quality is not one of which humans are directly aware in undergoing visual experiences. It is not a quality to which the human visual system is ‘tuned’. Thus, I grant that an item, in looking red, does not look to possess the quality of having (or being) the color of most fire-engines. This is to be expected, given that sameness of phenomenal look depends, I claim, on sameness of qualities represented. What is distinctive about the phenomenal use of ‘looks’ in the sentence ‘X looks F’ is that the quality ‘F’ stands for is one of which the relevant subject is directly aware in visual experience, as noted earlier, and further that ‘X looks F’ is understood as ‘F-ness is such that X looks to have it’, in the case that ‘F’ is a predicate, or as ‘F is such X looks to have it’, in the case that ‘F’ is an abstract singular term. Where these conditions are not both met, the use of ‘looks’ is epistemic and requires the subject to bring X under the relevant concept or concepts. What of the case in which the tiles look square, where square is the shape of the picture, but the picture does not look square in the given light? Here it may seem that the context is phenomenal and the tiles look square without looking the shape of the picture. But this is wrong. The tiles do look the shape of the picture; the tiles do not look the shape the picture looks (Tye 2000). The shape the picture looks is a different quality from the shape of the tiles. The latter is squareness; the former is not. The general point quickly illustrated with these examples is that, as far as the phenomenal look of something goes, what matters is the quality or qualities of which the subject is directly aware. How those qualities are conceived, what modes of presentation may or may not accompany the
172
Appendix
visual experience the subject undergoes, is irrelevant to the phenomenal look of the thing for the subject. The following argument: (1) Red is the disposition to reflect so-and-so percentages of the short, medium, and long wavelength incident light under normal viewing conditions;9 (2) X looks red; therefore, (3) X looks disposed to reflect so-and-so percentages of the short, medium, and long wavelength incident light under normal viewing conditions may seem to create trouble for the claim just made. For this argument seems clearly invalid; but reading the ‘looks’ in (3) phenomenally, so that (3) is understood as (3a) The disposition to reflect so-and-so percentages of the short, medium, and long incident light under normal viewing conditions is such that X looks to have it, (3) follows from (1) and (2) (given also the standard phenomenal reading of (2)). The obvious reply by the Millian is that the conclusion, (3), can be taken in more than one way. Reading the ‘looks’ in (3) epistemically as ‘looks to be’ or ‘looks as if it is’, the argument is indeed invalid. This, it seems to me, provides the most natural understanding of (3). The version of representationalism that is neither Millian nor Fregean—the position I call ‘hybrid’ above—is one that deserves further exploration. It is sometimes supposed that, in describing the phenomenology of experience, we must make use of the notion of the way a property or relation is
Representationalism
173
presented in experience; and this may seem to necessitate a shift away from the Millian view toward at least a hybrid position. For example, Chris Peacocke (forthcoming) says: We will not do justice to the . . . phenomenology of experience if we restrict ourselves to those contents which can be built up by referring to the properties and relations which the perceived objects are represented by the experiences as possessing.
He continues: The same shape can be perceived in two different ways, and the same holds for shape properties, if we regard them as within the representational content of experience. Mach’s example of one and the same shape that can be perceived either as a square or as a regular diamond is a familiar example. . . . [A]n object can be perceived either as a square, or as a diamond, in either of the standard orientations relative to the perceiver.
The example just cited can easily be accommodated by the Millian, however. It is evident that experiences represent both objective spatial properties and viewer-relative ones (for example, directional properties such as being to the left). The most straightforward explanation of the fact that an object experienced from one point of view as diamondshaped is not experienced as diamond-shaped from another suitably different point of view without either experience being inaccurate is that there is a viewpoint-relative property of being diamond-shaped that is represented in the content of the former experience but not in the content of the latter. This property is also context-relative; for an object seen against one background setting may be experienced as diamond-shaped without being experienced as diamondshaped against a second setting, again without any inaccuracy.10 There is also a viewpoint-relative, context-relative property of being square. This property is not the same as
174
Appendix
the property of being regular diamond-shaped. For where the viewpoint and context are held fixed, an object may be square without being regular diamond-shaped (or vice versa). This difference in properties at the level of nonconceptual content suffices to ground the phenomenal difference between something looking square and its looking regular diamond-shaped (in a different setting or from a different point of view). Modes of presentation of properties are not needed. The hybrid position also faces some difficult questions that the Millian position does not. If there are indeed nonconceptual sensory modes of presentation, is there one generic mode of presentation of this sort? Is there one for each sense? Or are there modes that vary within a sense? If so, how finely are they to be individuated? And what is it about these modes that makes them nonconceptual? These are questions that lie beyond the scope of this appendix. So much for the Millian aspect to my view. The externalism in my position is qualified, since I doubt very much whether it is possible for creatures as sophisticated in their psychology and behavior as human beings to be phenomenally different and yet nonetheless also be molecular duplicates. If there were phenomenal differences in such creatures, it seems to me that those differences would show up in narrow functional differences and those differences would be incompatible with molecular identity. In the case of color experiences, for example, if your color experiences were subjectively inverted relative to mine, we would exhibit functional differences. These would arise, since there are more determinate hues between unique red and unique yellow than between unique green and unique blue, and dark blue is still a blue whereas dark yellow is brown.11 Still, I am inclined to think that with very simple creatures without the
Representationalism
175
capacity to introspect and limited in their behavioral responses, there could be molecular duplicates who differed phenomenally. And for this reason, I am an externalist. As for the functional conditions on content, I claim that the relevant contents must be poised to make the right sort of difference with respect to cognitive responses. This bears a little further comment. For the purposes of illustration, let me focus again on the example of visual experience. Intuitively, visual experiences are not themselves beliefs, but they are apt for the production of beliefs. Admittedly, some states that might reasonably be classified as visual experiences, for example, seeing that the table is covered with books, already involve beliefs or belieflike states. But such states, in my view, are hybrid, having a visual experience proper and a belief or thought as components. Visual experiences proper are not apt for the production of any old beliefs, however. Intuitively, each visual experience is the direct basis for the formation of a belief about the perceptible qualities represented by the experience. Each experience is also, in creatures equipped with the capacity to introspect, the direct basis for the formation of beliefs about the experience and its content. The content of the visual experience proper supplies the input to the relevant belief-forming processes, where the role of the belief-forming processes is to generate beliefs of the sorts just described. But the appropriate beliefs are not always formed, of course; for introspection can malfunction and, at least in the case of external belief-formation, other background beliefs can interfere. There is also the possibility that attention is not appropriately directed. A visual experience has a poised content, then, in my view, so long as it is apt for the production in the right ways of the right beliefs. Likewise for the other senses. In the case
176
Appendix
of bodily experiences, desire is also relevant. The experience of pain, for example, is the direct basis for the desire to protect oneself, to avoid damage. On my view, the phenomenal character of an experience is one and the same as its poised, abstract, nonconceptual, intentional content, or its PANIC, for short.12 This is the version of representationalism assumed in the book, but it should be clear from what I have said above that my proposals on unity may be extended mutatis mutandis to other versions of representationalism.13
Notes
Introduction 1. The original distracted driver case is due to David Armstrong. See his (1968), p. 93. 2. Cases 2 and 3 are to be found in Dennett (1991). 3. See Rosenthal (1986). 4. John Searle discusses a case of this sort in his (1992), pp. 14–165. 5. For more here, see Tye (1993b). 6. The claim that seeing an object requires that the object visually look some way to the perceiver is given an extended defense in Dretske (1969). 7. For the purposes of illuminating the concept of P-consciousness, it is not necessary that these hypotheses express metaphysical possibilities. Mere conceivability suffices. See Block (1993). 8. Penfield (1975) describes epileptics who have petit mal seizures while driving or walking. According to Penfield, these patients become automata during the epileptic disorders: they continue what they are doing in a purely mechanical, automatic way without any consciousness. This claim is echoed by Searle in his (1992). It seems unreasonably strong, however, to conclude that there is no consciousness at all. Granted, there is no I-consciousness, and only limited D- and R-consciousness, but what reason is there to suppose that the patients have no P-consciousness? Interestingly, in his description of the patients, Penfield does not allude to any sensory impairments. See Block (1995).
178
Notes
9. One putative solution to the binding problem at the neurological level is that there is a common neuronal oscillation (40 MHz) that binds together the relevant neural events. This is known as the 40 MHz hypothesis. See Crick and Koch (1990). 10. One such effect is the McGurk effect. Here, seen lip movements can alter which phoneme is heard for a particular sound.
Chapter 1 1. I don’t believe that this is really possible. For more, see (14)–(16) of this chapter. 2. For a deeper reason why phenomenal unity is not to be identified with introspective unity, see (14)–(17) and section 1.4 of this chapter. 3. For a defense of the claim that split-brain subjects have phenomenally disunified experiences, see chapter 5. 4. This claim is one that the sense-datum theorists would have endorsed, although they would have insisted that the things apparently outside are really immaterial surfaces or sense-data rather than physical surfaces. After all, sense-datum theorists were at pains to distinguish the act of sensing from the thing sensed. G. E. Moore (1903) is the modern father of transparency. 5. There are dissimilarities. In typical cases of seeing-that, background beliefs play a role in generating the propositional state of awareness. This is not so in the case of introspection. For more here, see Tye (2000), chapter 3. 6. Not everyone accepts this claim. On the view of events elaborated by Jaegwon Kim (1976) and Alvin Goldman (1970), the event of x’s F-ing G-ly is a complex entity consisting of x and the property of F-ing G-ly. This has the consequence that at the time at which (S*) is true, there are four relevant simultaneous events: Jones’s writing painstakingly and illegibly, Jones’s writing painstakingly, Jones’s writing illegibly, and Jones’s writing. Intuitively, however, events do not individuate in this hyper-fine-grained way. 7. I am not suggesting here that object-unity is the same as phenomenal unity. See paragraph (5) earlier in this chapter. 8. For an elucidation of what it is for a content to be nonconceptual, abstract, and poised, see Tye (1995, 2000). For further critical discussion and replies, see the web symposium on Tye (2000) at http://host.uniroma3.it/ progetti/kant/field/tyesymp.htm.
Notes
179
9. For a discussion of split brains, see chapter 5. In my view, it is a mistake to suppose that the perceptual consciousness of the split-brain subject is always divided after the commissurotomy. Indeed, it is a mistake to suppose that even in the highly specialized circumstances in which split-brain subjects typically behave anomalously, their consciousness is invariably divided. 10. Actually, what really happens is that when one feels the stick, it no longer looks bent: touch corrects vision. But this does not matter for present purposes, so let us ignore it. 11. I do not deny that perceptual experiences sometimes have conceptual contents too.
Chapter 2 1. See Noordhof (2000). 2. The representational content of pain is more complex than this. See pp. 56–60 below. For the moment, the complications may be ignored. 3. Again, this oversimplifies. 4. Or as qualities of those qualities. To clarify this point: in having the pain experience, one experiences certain localized qualities as bad or unpleasant. These localized qualities along with their unpleasantness are the qualities to which one’s attention goes, if one is told to introspect one’s pain experience. Unpleasantness is a quality of the former qualities in the given context. (For more on the affective side of pain, see later in this chapter.) Compare this with the case of experiencing red as pleasing in one context, that of a particular painting with various other complementary background colors, but not as pleasing in another, that in which the red clashes with the background. 5. For useful summaries here, see Melzack and Wall (1983), Price (1999, 2000), and Chapman and Nakamura (1999). 6. The claim that pain essentially has a certain sensory character been disputed by Maurat Aydede (2001) via an appeal to some recent scientific findings by Ploner et al. (1999). Unfortunately, Aydede’s position is unfounded. Ploner et al. demonstrated the loss of pain sensation with continuing pain affect in a 57-year-old male, who had undergone a right-sided postcentral stroke. They did not demonstrate the continuing experience of pain without the sensory component, however. In response to certain painful stimuli, the
180
Notes
patient described the emergence of a “clearly unpleasant” feeling in an extended area “somewhere between the fingertips and the shoulder” that he wanted to avoid. But he was unable to describe the experience further. Moreover, he rejected suggestions from a word list containing ‘warm’, ‘hot’, ‘cold’, ‘touch’, ‘burning’, ‘pinprick-like’, ‘slight pain’, ‘moderate pain’, and ‘intense pain’. 7. Cf. Armstrong (1962). 8. I do not mean to suggest here that one cannot have a stabbing pain unless one has the concept of a dagger. Pains, in my view, are nonconceptual representations. 9. The suggestion that the pleasingness of orgasms is part of their representational content is made in Tye (1995b). It is also the view taken by Andrew Melnyk (1999). 10. Thus tissue damage that is not experientially represented is not pain. 11. The same view of itches and tickles is adopted in Armstrong (1962). 12. This feeling typically elicits the desire or urge to eat, just as the feeling of pain typically causes the strong desire that it cease. 13. According to Ramachandran, this experiment worked on about half of the twenty people he tried it on. 14. Let me emphasize: I do not mean here that each pain is essentially felt within the actual body of the owner. Rather each pain is felt within a region that is felt by the owner to lie inside his body. 15. There is also the earlier worry about whether there is a maximal or overall experience at all. See p. 22.
Chapter 3 1. See Rock (1983) for other examples. Interestingly, Rock has shown that items sensed only tactually are experienced as different, when their orientations are changed. This results in the items’ not being recognized in the unfamiliar orientations. 2. It is worth noting here that experiments with luminous rods show that vertical rods typically continue to look vertical even to tilted observers. Thus, the actual orientation of the torso is not of crucial importance to the apparent verticality of the rods. The key, it seems, is the direction of the pull of gravity on the torso.
Notes
181
3. Assuming there is normally no error in our experiences in such cases. 4. This case is inspired by Dennett (1978), and similar to one presented in Dainton (2000), p. 66. 5. Closure under conjunction is discussed in chapter 1, pp. 36–37 and chapter 2, p. 66. 6. For a still more extreme imaginary case in which it is for the subject as if two different worlds are present, see Dainton (2000), pp. 67–70. 7. I do not wish to deny that in some cases, thoughts have associated images of a nonauditory sort (e.g., visual images) that contribute to the phenomenology. 8. Brought to my attention by Bill Lycan. 9. Cf. Lycan (forthcoming). 10. One difference from the case of pains, itches, etc. is that (arguably) we allow moods to exist even at times at which they are not experienced. This is reflected in a difference in the use of terms for moods. We apply such terms not only to experiences but also, on occasion, to state types represented by experiences even at times when those types are not experientially represented.
Chapter 4 1. The memory account could be complicated in various ways. But none that I have seen is satisfactory. For objections, see Lockwood (1989). And with the complications, the claim to have the most parsimonious account goes out the window anyway. 2. This point is made by Dennett (1991), p. 114. 3. As with the first proposal above (in paragraph (8)), or one possible version of it, about the times of experiences relative to the specious presents they represent. 4. Whether it does so permanently afterward or whether the split consciousness is restricted to those times at which the subject is in the appropriate experimental situations need not concern us just yet. See chapter 5. 5. What if even during deep sleep, there is always some consciousness? Then there is but one extended period of consciousness throughout the
182
Notes
person’s lifetime, and one stream or extended experience, the content of which during deep sleep is vastly impoverished in comparison to its content during normal waking moments. 6. I do not deny that often thoughts are associated with visual and kinesthetic images. 7. I am in agreement here with Dainton (2000), p. 131.
Chapter 5 1. Sperry described his subjects as each having “two free wills in one cranial vault.” Roland Puccetti (1973) takes the even stronger position that reflection on the split-brain cases shows that we are all composites of two minds and two persons! 2. For more here, see my (1993c). 3. This is the view of Bayne and Chalmers (2003). 4. Blindsight has been discussed by a number of philosophers. See, e.g., Heil (1983), Dennett (1991), McGinn (1991), Tye (1993a, 1995b), and Block (1995). 5. Some philosophers have suggested that, in fact, blindsight subjects really have unconscious beliefs with respect to the blind field while remaining fully phenomenally conscious (see, e.g., Heil 1983). This is problematic for two reasons. First, there is no reason to think that there is anything wrong with the mechanism of introspective awareness in such subjects. The brain damage, after all, is located in the geniculo-striate pathway and the occipital cortex (the locus of visual sensations). Second, if the beliefs are present, introspected or not, then why don’t they play any rational role in guiding behavior? 6. Nothing in this view of visual experience compels the admission that the ways in which we conceive of things can never have any effect on how they phenomenally appear. Conceiving of a scene in one way rather than another may sometimes influence how we break it up cognitively into spatial parts, for example, and the shapes we then experience may not be the ones we would have experienced under a different conceptualization. But the sensory experiences of those shapes do not require shape concepts. As just noted, they are nonconceptual. 7. Of course, visual recognition, seeing that something is an F, does demand possession (and application) of the concept F, even where F is a
Notes
183
shape. In cases of this sort, however, there are two elements at play: the basic visual experience and the judgment it elicits. The judgment is conceptual; the experience not. So, the states are really hybrid. 8. This being so, there is no real mystery about the function of phenomenal perceptual consciousness. Phenomenal consciousness, in the case of perceptual experiences, has as its purpose to enable creatures to recognize things in the world and to behave appropriately toward them by channeling information about them from the senses to the centers of reasoning and action. See Tye (1996b). 9. Others who have discussed the question of whether phenomenal unity is nontransitive include Lockwood (1989), Hurley (1998), and Dainton (2000).
Chapter 6 1. Cf. Lewis (1976). 2. According to epistemic theorists (Sorenson 1988, Williamson 1994), vagueness is a matter of ignorance. On this view, the fuzziness of Everest’s boundaries is a reflection of the fact that we do not know exactly where the boundaries lie. Our conceptual mechanisms are simply not equipped to make the necessary fine-grained discriminations. Epistemic theorists thus grant that some molecules are neither definitely inside nor definitely outside Everest, but they insist that this is only in the sense that some molecules are not known to be inside and not known to be outside either. Stronger versions of the epistemic view hold not merely that the dividing line is not known but also that it cannot be known. Again, this seems very counterintuitive. Our ordinary concept of a fuzzy boundary is one of a boundary that is nonepistemically fuzzy. Intuitively, not even God knows where Everest’s boundaries lie any more than God knows which hair the addition of which turns a man who is bald into one who is not. To be sure, there is a sense of the operator ‘definitely’ that is epistemic, as, for example, when I say, on hearing of a photo-finish in a hundred-meter race, “It’s not definite yet whether NN won,” meaning that it isn’t publicly known yet whether NN nudged out the other runners for the victory. But there is also a nonepistemic sense of ‘definitely’, as when ‘Definitely p’ is correctly inferred from ‘It is a fact that p’. In having epistemic and metaphysical senses, the operator ‘definitely’ is like the operator ‘possibly’. And intuitively, it is the metaphysical sense that is relevant to the claim that there are objects such that it is indefinite just where their boundaries lie.
184
Notes
3. Lewis adopts the counterintuitive position that there are no things with vague boundaries in large part because he is persuaded by Peter Unger’s Problem of the Many (1979), which he takes to generalize from Unger’s case of a cloud to all the manifest objects of commonsense. He comments: “Once noticed, we can see that [the Problem of the Many] is everywhere, for all things are swarms of particles. There are always outlying particles, questionably parts of the thing, not definitely included and not definitely not included. So there are always many aggregates, differing by a little bit here and a little bit there, with equal claim to be the thing. We have many things or we have none, but anyway not the one thing we thought we had. That is absurd” (1993). I find this line of argument unconvincing, and I have offered criticisms of it elsewhere (Tye 1996c). 4. It certainly seems reasonable to suppose that Evans himself intended that ‘a’ and ‘b’ be taken to be precise designators for vague objects, although he did not actually say this. After all, his target is the philosopher who believes that the world itself is vague, not the philosopher who believes that vagueness resides in how language latches on to the world. 5. Material in brackets added. 6. Cf. Copeland (1995), p. 87. 7. What I say here is similar to, and influenced by, what Sainsbury says (1995, pp. 74–75) about the identity ‘That watch is the watch I sent for repair’. On this point he and I are in agreement. 8. Likewise, of course, for the description ‘the club meeting at t and later’. 9. In my (2001), I took the view that (11) is false, even in the case in which the new members have no relevant intentions. I now think that the argument I gave there for this conclusion is flawed. 10. These points undermine the following objection (by Keith Hossack) to my overall view on vagueness and identity. There is a cloud in the sky. If there are vague objects, then this cloud is one of them. Call it ‘Fred’ (so that ‘Fred’ is a precise designator for a vague object). Water droplets in Fred’s vicinity are made to disappear, one by one. At the end of the process, Fred no longer exists. Intuitively, there is a time, somewhere in the middle of the removal process, at which it is indeterminate whether Fred exists. But this demands that it be indeterminate whether Fred is identical with one of the things that exist. And that contradicts my claim that there are no indefinite identity statements with precise designators for vague objects. My response to this line of reasoning is to say that it involves a non sequitur. Existence at a time is not the same as existence simpliciter. Existence at time t is a property (expressible in the predicate ‘x exists at t’),
Notes
185
and, as the case of Fred shows, it does indeed admit of borderline cases. But it does not follow from this that it is indeterminate whether Fred exists, period. After all, there is an object that ‘Fred’ denotes, namely, Fred. So, there is no indeterminacy either in whether Fred is identical with one of the things that exist.
Appendix 1. As should be clear from remarks made throughout this book. See especially chapter 1, pp. 22–25. 2. This claim, it is worth noting, fits well with the linguistic constructions that are naturally employed in connection with such awareness. To talk of our being aware of the phenomenology of an experience or of how an experience “feels” is to use a generic perceptual verb (‘aware of’) followed by an abstract noun (‘the phenomenology’) or an interrogative nominal (‘how the experience feels’). In cases of this sort, where there is a perceptual verb, the abstract noun or interrogative nominal typically stands in for a factive clause so that what is being described is (a species) of awareness of some fact. For example, if I am described as hearing the answer to your question or as seeing who is at the door, I do not satisfy the description merely by hearing the sentence that is the answer or seeing the person who is at the door. I must be aware that the given sentence is the answer to your question, that the given person is the one at the door. In short, I must be aware of some appropriate fact. Likewise in the case of awareness of the phenomenal character of a current experience. For more on this, see Dretske (1993). 3. I ignore here the case of phantom limb sensations, for which there is no relevant limb to feel. 4. The terms ‘Fregean’ and ‘Millian’ in this context are due to Chalmers (forthcoming). 5. So, my representationalism is not intended to have the status of an a priori conceptual truth. For more on phenomenal concepts, see my (1999) and (forthcoming, 2003b). 6. In Tye (1995), I took a hybrid position; in Tye (2000) my position is Millian. 7. Dan Stoljar made this point in conversation. 8. In saying that the context is phenomenal, I am assuming that colors are among the qualities of which humans are directly aware. Not everyone
186
Notes
accepts this assumption. See, e.g., Shoemaker (1996a). For criticisms of Shoemaker’s position, see Tye (2000). 9. See Bradley and Tye (2002). 10. For an example, see Peacocke (1992), p. 118. 11. These asymmetries are noted in Shoemaker (forthcoming). 12. For detailed discussion and criticisms of this theory along with my replies, see the web symposium at http://host.uniroma3.it/progetti/kant/ field/tyesymp.htm. See also the shorter symposium on Tye (2000), in my (forthcoming, 2003a). 13. For a more elaborate taxonomy of possible representationalist positions, see Chalmers (forthcoming).
References
Armstrong, D. 1962. Bodily Sensations. London: Routledge and Kegan Paul. Armstrong, D. 1968. A Materialist Theory of Mind. London: Routledge and Kegan Paul. Aydede, M. 2001. “Naturalism and Direct Realism about Pain.” Consciousness and Emotion 2: 29–73. Bayne, T. and Chalmers, D. 2003. “What Is the Unity of Consciousness?” In The Unity of Consciousness: Binding, Integration, Dissociation, ed. A. Cleeremans, Oxford: Oxford University Press. Bekesy, G. von. 1967. Sensory Inhibition. Princeton, N.J.: Princeton University Press. Benchley, R. 1921. Inside Benchley. New York: Harper and Bros. Block, N. 1983. “The Photographic Fallacy in the Debate about Mental Imagery.” Nous 17: 654–664. Block, N. 1993. “Review of Dennett’s Consciousness Explained.” Journal of Philosophy 90: 181–193. Block, N. 1995. “On a Confusion about a Function of Consciousness.” Behavioral and Brain Sciences 18: 227–247. Bradley, P. and Tye, M. 2002. “Of Colors, Kestrels, Caterpillars, and Leaves.” Journal of Philosophy 98: 469–487. Broad, C. 1923. Scientific Thought. London: Routledge and Kegan Paul. Brook, A. 1994. Kant and the Mind. New York: Cambridge University Press.
188
References
Burge, T. 1986. “Individualism and Psychology.” Philosophical Review 95: 3–45. Carnap, R. 1967. The Logical Structure of the World. Berkeley: University of California Press. Chalmers, D. Forthcoming. “Varieties of Representationalism.” Chapman, C. and Nakamura, Y. 1999. “A Passion for the Soul: An Introduction to Pain for Consciousness Researchers.” Consciousness and Cognition 8: 391–422. Confer, W. and Ables, B. 1983. Multiple Personality: Etiology, Diagnosis, and Treatment. New York: Human Sciences Press. Copeland, J. 1995. “On Vague Objects, Fractal Logic, and Fuzzy Boundaries.” Southern Journal of Philosophy (1994 Spindel Conference on Vagueness) 33: 83–96. Crick, F. and Koch, C. 1990. “Towards a Neurobiological Theory of Consciousness.” Seminars in the Neurosciences 2: 263–275. Dainton, B. 2000. The Stream of Consciousness. London: Routledge. Dennett, D. 1978. Brainstorms. Cambridge, Mass.: MIT Press/Bradford Books. Dennett, D. 1991. Consciousness Explained. Boston: Little, Brown. Descartes, R. 1641. Meditations on First Philosophy. Paris: Michel Soly. Dretske, F. 1969. Seeing and Knowing. Chicago: University of Chicago Press. Dretske, F. 1993. “Conscious Experience.” Mind 102: 263–283. Dretske, F. 1995. Naturalizing the Mind. Cambridge, Mass.: MIT Press/ Bradford Books. Eagleman, D. and Sejnowski, T. 2000. “Motion Integrations and Postdiction in Visual Awareness.” Science 287: 2036–2038. Evans, G. 1978. “Can There Be Vague Objects?” Analysis 38: 208. Flanagan, O. 1992. Consciousness Reconsidered. Cambridge, Mass.: MIT Press/Bradford Books. Foster, J. 1979. “In Self-Defence.” In Perception and Identity, ed. C. Macdonald. London: Macmillan.
References
189
Goldman, A. 1970. A Theory of Human Action. Englewood Cliffs, N.J.: Prentice-Hall. Gregory, R. 1988. “Consciousness in Science and Philosophy: Conscience and Conscience.” In Consciousness in Contemporary Science, ed. A. Marcel and E. Bisiach. Oxford: Oxford University Press. Head, H. 1920. Studies in Neurology, volume 2. Oxford: Oxford University Press. Heil, J. 1983. Perception and Cognition. Berkeley: University of California Press. Hume, D. 1739. Treatise on Human Nature. London: John Noon. Hurley, S. 1998. Consciousness in Action. Cambridge, Mass.: Harvard University Press. Jackson, F. 1977. Perception. Cambridge: Cambridge University Press. James, W. 1952. The Principles of Psychology. Chicago: Encyclopedia Brittanica. Kant, I. 1980. Critique of Pure Reason. Trans. Kemp Smith. London: Macmillan. Kim, J. 1976. “Events as Property Exemplifications.” In Action Theory, ed. M. Brand and D. Walton, pp. 159–177. Dordrecht: Kluwer. Lewis, D. 1976. “Survival and Identity.” In The Identities of Persons, ed. Amelie Rorty. Berkeley: University of California Press. Lewis, D. 1986. On the Plurality of Worlds. Oxford: Blackwell. Lewis, D. 1988. “Vague Identity: Evans Misunderstood.” Analysis 48: 135–136. Lewis, D. 1993. “Many, but Almost One.” In Ontology, Causality, and Mind: Essays on the Philosophy of D.M. Armstrong, ed. Keith Campbell, J. Bacon, and L. Reinhardt. Cambridge: Cambridge University Press. Lockwood, M. 1989. Mind, Brain, and the Quantum. Oxford: Oxford University Press. Lycan, W. 1997. “Consciousness as Internal Monitoring.” In The Nature of Consciousness, ed. N. Block, O. Flanagan, and G. Güzeldere. Cambridge, Mass.: MIT Press/Bradford Books. Lycan, W. Forthcoming. “The Case for Phenomenal Externalism.”
190
References
Mabbott, J. 1951. “Our Direct Experience of Time.” Mind 60: 153–167. Marcel, A. J. 1986. “Consciousness and Processing: Choosing and Testing a Null Hypothesis.” Behaviorial and Brain Sciences 9: 40–41. Marks, C. 1980. Commissurotomy, Consciousness, and Unity of Mind. Cambridge, Mass.: MIT Press/Bradford Books. Maund, B. 2002. “Michael Tye on Phenomenal Character and Color.” Online at http://host.uniroma3.it/progetti/kant/field/tyesymp.htm. McGinn, C. 1991. The Problem of Consciousness. Oxford: Blackwell. Melnyk, A. 1999. “Comment on Schroeder.” Paper presented at APA Pacific Meeting. Melzack, R. and Casey, K. 1968. “Sensory, Motivational, and Central Control Determinants of Pain: A New Conceptual Model.” In The Skin Senses, ed. D. Kenshalo. Springfield, Ill.: C. C. Thomas. Melzack, R. and Wall, P. 1965. “Pain Mechanisms: A New Theory.” Science 150: 971–979. Melzack, R. and Wall, P. 1983. The Challenge of Pain. New York: Basic Books. Miller, I. 1984. Husserl, Perception, and Temporal Awareness. Cambridge, Mass.: MIT Press. Moore, G. 1903. “The Refutation of Idealism.” In Philosophical Papers. London: Routledge and Kegan Paul. Nagel, T. 1971. “Brain Bisection and the Unity of Consciousness.” Synthese 22: 396–413. Noordhof, P. 2001. “In Pain.” Analysis 61: 95–97. Parfit, D. 1984. Reasons and Persons. Oxford: Oxford University Press. Parfit, D. 1987. “Divided Minds and the Nature of Persons.” In Mindwaves, ed. C. Blakemore and S. Greenfield. Oxford: Blackwell. Parsons, T. 1972. “Some Problems Concerning the Logic of Grammatical Modifiers.” In Semantics of Natural Language, ed. D. Davidson and G. Harman, pp. 127–141. Dordrecht: Reidel. Peacocke, C. 1992. “Scenarios, Concepts and Perception.” In The Contents of Experience, ed. T. Crane, pp. 136–157. Cambridge: Cambridge University Press.
References
191
Peacocke, C. 1994. Objectivity, Simulation, and the Unity of Consciousness. Oxford: Oxford University Press. Peacocke, C. Forthcoming. “Does Perception have a Nonconceptual Content?” Penfield, W. 1975. The Mystery of the Mind: A Critical Study of Consciousness and the Human Brain. Princeton, N.J.: Princeton University Press. Ploner, M., Freund H., and Scnitzler, A. 1999. “Pain Affect without Pain Sensation in a Patient with a Postcentral Lesion.” Pain 81: 211–214. Price, D. 1999. Psychological Mechanisms of Pain and Analgesia: Progress in Pain Research and Management, vol. 15. Seattle: IASP Press. Price, D. 2000. “Psychological and Neural Mechanisms of the Affective Dimension of Pain.” Science 288: 1769–1772. Puccetti, R. 1973. “Multiple Identity.” The Personalist 54: 203–215. Ramachandran, V. and Blakeslee, S. 1998. Phantoms in the Brain. New York: William Morrow. Reid, T. 1788. Essays on the Active Powers of the Human Mind. Edinburgh. Rock, I. 1983. The Logic of Perception. Cambridge, Mass.: MIT Press/ Bradford Books. Rosenfield, I. 1992. The Strange, the Familiar, and the Forgotten. New York: Knopf. Rosenthal, D. 1986. “Two Concepts of Consciousness.” Philosophical Studies 49: 329–359. Rosenthal, D. 1997. “A Theory of Consciousness.” In The Nature of Consciousness, ed. N. Block, O. Flanagan, and G. Güzeldere. Cambridge, Mass.: MIT Press/Bradford Books. Sacks, O. 1984. A Leg to Stand On. New York: Touchstone. Sainsbury, M. 1995. “Why the World Could Not Be Vague.” Southern Journal of Philosophy (1994 Spindel Conference on Vagueness) 33: 63–81. Searle, J. 1992. The Rediscovery of the Mind. Cambridge, Mass.: MIT Press/ Bradford Books. Sellars, W. 1968. Science and Metaphysics. London: Routledge and Kegan Paul.
192
References
Shoemaker, S. 1996. “The Unity of Consciousness and the Consciousness of Unity.” In The First-Person Perspective and Other Essays. Cambridge: Cambridge University Press. Shoemaker, S. 1996a. “Qualities and Qualia: What’s in the Mind?” In The First Person Perspective and Other Essays. Cambridge: Cambridge University Press. Shoemaker, S. Forthcoming. “Content, Character, and Color: Against Standard Representationalism.” Sorensen, R. 1988. Blindspots. Oxford: Clarendon Press. Sperry, R. 1968. “Hemisphere Deconnection and Unity in Conscious Awareness.” American Psychologist 23: 723–733. Sprigge, T. 1993. American Truth and British Reality. La Salle, Ill.: Open Court. Stevenson, L. 2000. “Synthetic Unities of Experience.” Philosophy and Phenomenological Research 60: 281–305. Strawson, G. 1997. “The Self.” Journal of Consciousness Studies 4 (5–6): 405–428. Sutcliffe, J. and Jones, J. 1962. “Personal Identity, Multiple Personality, and Hypnosis.” The International Journal of Clinical and Experimental Hypnosis 10: 231–269. Trevarthen, C. 1970. “Experimental Evidence for a Brain-stem Contribution to Visual Perception in Man.” Brain, Behavior, and Evolution 3: 338–352. Tye, M. 1990. “Vague Objects.” Mind 99: 535–557. Tye, M. 1993a. “Blindsight, the Absent Qualia Hypothesis, and the Mystery of Consciousness.” In Philosophy and Cognitive Science, supplement to Philosophy 34, C. Hookway and D. Peterson, eds., pp. 19–40. Tye, M. 1993b. “Reflections on Dennett and Consciousness.” Philosophy and Phenomenological Research 53: 893–896. Tye, M. 1993c. “Image Indeterminacy: The Picture Theory of Images and the Bifurcation of ‘What’ and ‘Where’ Information in Higher-level Vision.” In Spatial Representation, ed. N. Eilan, R. McCarthy, and B. Brewer. Oxford: Blackwell. Tye, M. 1995a. Ten Problems of Consciousness: A Representational Theory of the Phenomenal Mind. Cambridge, Mass.: MIT Press/Bradford Books.
References
193
Tye, M. 1995b. “Blindsight, Orgasm, and Representational Overlap.” Behavioral and Brain Sciences 18: 268–269. Tye, M. 1996a. “The Burning House.” In Conscious Experience, ed. T. Metzinger. Berlin: Schoningh-Verlag Press. Tye, M. 1996b. “The Function of Consciousness.” Nous 30: 287–305. Tye, M. 1996c. “Fuzzy Realism and the Problem of the Many.” Philosophical Studies 81: 215–225. Tye, M. 1999. “Phenomenal Consciousness: The Explanatory Gap as a Cognitive Illusion.” Mind 108: 705–725. Tye, M. 2000. Consciousness, Color, and Content. Cambridge, Mass.: MIT Press/ Bradford Books. Tye, M. 2001. “Vagueness and Reality.” Philosophical Topics 28: 195–210. Tye, M. 2002. Web symposium on Consciousness, Color, and Content, at http://host.uniroma3.it/progetti/kant/field/tyesymp.htm. Also in Philosophical Studies (forthcoming 2003a). Tye, M. Forthcoming 2003b. “A Theory of Phenomenal Concepts.” Philosophy. Unger, P. 1979. “There Are no Ordinary Things.” Synthese 41: 117–154. Van Gulick, R. 1989. “What Difference Does Consciousness Make?” Philosophical Topics 17: 211–223. Weiskrantz, L. 1986. Blindsight: A Case Study and Its Implications. New York: Oxford University Press. Weiskrantz, L. 1990. “Outlooks for Blindsight: Explicit Methodologies for Implicit Processes.” Proceedings of the Royal Society London 239: 247–278. White, S. 1991. The Unity of the Self. Cambridge, Mass.: MIT Press/Bradford Books. Wiggins, D. 1967. Identity and Spatio-Temporal Continuity. Oxford: Blackwell. Williamson, T. 1994. Vagueness. London: Routledge. Zadeh, L. 1965. “Fuzzy Sets.” Information and Control 8: 338–353.
Index
Absent qualia hypothesis, 8 Access consciousness, 9 disunified (split-brain patients), 112, 121–125 Amputees. See Phantom limb experiences Anesthetization, and body image, 44 Apple, unity of experiences of, 18 Arm-movement example, 32 Attention, and introspection, 10 Auditory linguistic images, 80 and thought, 72–73, 79–80 Automaton, split-brain patient as, 112, 117 Awareness introspective, 5, 22–25, 95–96 and bundle theory, 134 in representationalist account, 165 Bayne, T., 20–21 Beer-and-ham-sandwich example, for one experience view, 26–27 Beliefs contradictory, 115–116 and visual experiences, 175 Benchley, Robert, 82 Binding problem, 12
Bird-watcher (case), 2, 6 Black’s/BLACK’S club (example), 161–162 Blindsight, 121–123, 124, 125 Block, N., 123–124, 125 Bodily experience, 68 and perceptual consciousness, 68–78 unity of, 49, 62–66 Bodily sensations, 49 of heat, 61 hunger pangs, 61 itches, 60–61 orgasm, 58–59 pains, 50–58, 59–60 (see also Pain) tastes, 58, 68–69 thirst, 61 tickles, 60 tingles, 61 touch, 68–69 Bodily unity, problem of, 62–66 Body image, 43–49. See also General bodily feeling and conscious thoughts, 81 and experience of contact, 69 malleability of, 62 Body transplants, and personal identity, 135–137, 149
196
Index
Brain, disembodied (examples), 71–75 Brain transplant with split brain, 149–151 Brief Encounter, The (case), 3, 6, 9–10 Broad, C. D., 92 Bundle theory of person, 133–134 objections to, 138–140 and subject-of-PF theory, 142 and unity of experience, 107 Buried-alive/roller-coaster example, 76–78, 118–119 Camus, P., 43–44 Carnap, Rudolf, 106–107 Casey, K., 55 Chalmers, D., 20–21 Cloud-and-droplets example, 29 Colored phi phenomenon (red-green flashes), 90–91, 96–97 Concrete individuals, and phenomenology, 168–169 Consciousness and Cartesian ego theory, 133 cases of, 2–5 and epileptics, 177n. kinds of access consciousness, 9, 112, 121–125 D-consciousness (discriminatory consciousness), 6, 8, 9 I-consciousness (introspective consciousness), 5–6, 7, 9, 10, 177n.8 P-consciousness (phenomenal consciousness), 7–11, 121–124, 126–129, 183n.8 (see also Phenomenal consciousness) R-consciousness (responsive consciousness), 6, 9 single subject of, 118
and stream metaphor, 105 (see also Streams of consciousness) as unified, xiv, 1 (see also at Unity) Conscious experiences. See Experience(s) Conscious thoughts, in unity with perceptual and bodily experiences, 78–81 Contradictory beliefs, and splitbrain patient, 115–116 Copeland, Jack, 158 Corpus callosum, 109. See also Split-brain patients Creature consciousness, 9 Dainton, Barry, 90 Dennett, G., 1, 56, 71 Deny, G., 43–44 Descartes, René and ego theory of person, 133 and unified consciousness, 1 Designators rigid and precise, 151–156 vagueness of, 155–156 Diachronic unity, 86–95 Disassociation, reactive, 56 Discriminatory consciousness (D-consciousness,), 6 as creature consciousness, 9 without P-consciousness, 8 Disembodied-brain examples, 71–75 Distracted Philosopher, The (case), 2, 5 Disunified access consciousness, in split-brain patients, 112, 121–126 Disunified experiences, in hallucinations and illusions, 37–38 Disunified phenomenal consciousness, and split-brain patients, 126–129, 134, 135
Index
Dog, sleeping (case), 4, 10–11 Do–re–mi (musical scale) example, 87–88, 94, 97, 99–100, 106 Dreamer, The (case), 4, 10 Dretske, Fred, 24 Eagleman, D., 91–92 Ego theory of person, 133, 153–154 objections to, 134–138 Emotions, 81. See also Moods, felt Epileptics, and consciousness, 177n.8 Evans, Gareth, 153–154, 155, 157, 159, 162–163 Everest, Mount, as vagueness example, 156, 157, 158, 183–184n.3 Experience(s) bodily, 68–78 (see also Bodily sensations) disunified, 37–38 individuation of through time, 34, 98–99 and introspection, 22–25, 95–96 one experience view, 25–35, 39–40 for bodily experience, 65–66 and individuating of experiences through time, 98 and perceptual-bodily unity, 76 PANIC (poised, abstract, nonconceptual, intentional content) of, 176 as maximal PANIC states, 40, 99 perceptual phenomenal or subjective aspects of (case), 3–4, 8 presentness in, 86 redundancy in generation of, 127–128 unity of, 17–41 of unifying relation, 21–22 Experience, unity of. See at Unity
197
Experienced present. See Specious present(s) Externalist representationalism, 167, 174–175 Feeling(s). See also Bodily sensations phenomenal or subjective aspects of (case), 3–4, 8 physical basis of, 8–9 as private, 50 of succession, vs. succession of feelings, 86, 102 Felt moods, 81–84 persistence of, 85–86 Flash-lag illusion, 91 Fregean representationalism, 167–168 Fuzzy logic, 160 General bodily feeling, 43, 48, 63 as torso-relative, 48–49 unity of, 47 and unity of bodily experience, 64 Gestalt unity, 13 and McGurk effect, 178n.10 Glass partitions metaphor, 22–24 Gregory, Richard, 44, 45 Hallucinations and concrete individuals, 168–169 disunified experiences in, 37–38 in “Haunted” Graveyard case, 5, 11 and introspective awareness, 24 phantom limb pain as, 54 and phenomenal content, 36 and representation, 64 and unity of experience through time, 98 Handwriting example, for one experience view, 25–26 “Haunted” Graveyard, The (case), 5, 11
198
Index
Headache, discontinuous (case), 3, 6–7 Heat, feeling of, 61 Here experience of, 70 world in relationship to, 75 Hume, David, on unity of experience, 102, 105 and bundle theory of person, 107, 133 Hunger pangs, 61 Hybrid representationalism, 168, 169, 172–174 Identity, personal. See Person and personal identity Illusions disunified experiences in, 37–38 of feeling someone else’s nose, 61–62 flash-lag, 91 and phenomenal content, 36 “Impossible figure,” 38, 39 “In,” and pain, 51–52, 53 Individuation of experiences, through time, 34, 98–99 Infinite regress, in problem of unity of conscious experiences, 21–22 Internalist representationalism, 167 International Association for the Study of Pain, 50 Introspection and act of attention, 10 and awareness of experience, 22–25, 95–96 and displaced perception, 24 Introspective awareness, 5 and bundle theory, 134 Introspective consciousness (I-consciousness), 5–6 as creature consciousness, 9 and epileptics, 177n.8 without P-consciousness, 7, 10
Introspective unity, 13 vs. phenomenal unity, 20 Inverted qualia hypothesis, 8 “Is,” of identity vs. of composition, 142–143 Itches, 60–61 Jackson, Frank, 170 James, William, 86, 102, 104 Kant, Immanuel and phenomenal unity, 20 and subject unity, 12–13 and unified consciousness, 1 Leibniz’s Law, 29, 154, 157–158, 162 Lewis, David, 155–156, 157, 160 Linguistic auditory images, 80 and thought, 72–73, 79–80 Logical Structure of the World, The (Carnap), 106 “Looks” talk, 35, 169–172 Macbeth, disunified dagger experience of, 37, 38, 80 Mach, Ernst, 173 Madame I (patient with lost body image), 43–44, 45, 62, 69, 73–74 Materialist form of ego theory on person, 135–138 Maund, Barry, 63 Maximal PANIC states, 40, 99 McGurk effect, 178n.10 Melzack, R., 55 Memory, short-term phenomenal, 87 Miller, I., 89–90 Millian representationalism, 168, 172, 173, 174 Monet-painting example, 47–48 Monty Python viewing example, 74–75
Index
Moods, felt, 81–84 persistence of, 85–86 Movie analogy, 99 Multiple experiences, and problem of unity, 17–21 Multiple personality disorder and bundle theory of person, 138–139 and persons as material substances, 137–138 and single brain as more than one person, 142 and split brains, 111–112, 113–116 Musical scale (do-re-mi) example, 87–88, 94, 97, 99–100, 106 Nagel, T., 117–120, 125 Neurophysiological unity, 12 Neuropsychology, and unified consciousness, 1 Nonreductive strong representationalism, 167 Nontransitivity of phenomenal unity, 113, 129–132 Object unity, 11–12 and phenomenal unity, 19 One experience view, 25–35, 39–40 for bodily experience, 65–66 and individuating of experiences through time, 98 and perceptual-bodily unity, 76 Order of representations, vs. represented order, 90 Orgasm, 58–59 Pain(s), 50–58, 59–60 affective component of, 55–56, 57–58 and belief production, 175–176 and causal sense of “in,” 51–52 and consciousness, 3, 7 localization of, 63
199
physical basis of, 9 and projection, 63–64 Painting example, 47–48 PANIC (poised, abstract, nonconceptual, intentional content) states, 176 maximal, 40, 99 Parfit, Derek, 134, 135, 147–148, 160–161 Party Animal, The (case), 4, 6 Peacocke, Chris, 173 Perception, and consciousness, 2 in Distracted Philosopher case, 2 Perceptual consciousness and bodily experience, 68–78 D-consciousness as, 6 (see also Discriminatory consciousness) Perceptual experience(s) phenomenal or subjective aspects of (case), 3–4, 8 presentness in, 86 redundancy in generation of, 127–128 unity of and one experience view, 25–35, 39–40 as problem, 17–25 and synchronic phenomenal unity, 36–41 Person and personal identity bundle theory on, 133–134 objections to, 138–140 and subject-of-PF theory, 142 and unity of experience, 107 ego theory on, 133, 153–154 objections to, 134–138 problem cases for body transport, 147–148 radical discontinuity between life stages, 150–153, 162 split-brain subject, 111–112, 115–117, 143–144
200
Index
Person and personal identity (cont.) split-brain transplants, 148–151 teletransportation, 144–148 as subject of distinct psychological framework (PF), 140–143 and unity of experience, xiv through time, 102–104 vagueness in, 154–163 PF. See Psychological framework Phantom limb experiences, 45–46 as misrepresentation, 49 and pain, 54 as representing bodily disturbances, 61 Phenomenal character, attended and unattended, 10 Phenomenal consciousness (P-consciousness), 7–11, 183n.8 and blindsight, 122–124, 125 without D-consciousness, 8 disunified (split-brain patients), 126–129, 134, 135 and hypotheses of inverted and absent qualia, 8 without I-consciousness, 7, 10 and object unity, 12 Phenomenal flow, 108 Phenomenal look, 169–172 Phenomenal memory, short-term, 87 Phenomenal succession, 101 Phenomenal unity, 13, 15, 20, 36, 84, 107 direct and indirect, 100 vs. introspective unity, 20 nontransitivity of, 129–132 as relation between qualities experienced, 102 synchronic (of simultaneous experiences), 19, 35, 36–41, 84 and wine taster example, 27
Phenomenal unity relation, 95, 107, 152–153. See also Unity of experience through time and moods, 83 nontransitivity of, 113 Phenomenological unity, 19, 20–21 of bodily experiences or sensations, 49, 63, 66 and sense-specific experiences, 28 Phenomenology and concrete individuals, 168 of occurrent thoughts, 79–80 technicolor, 8 of thinking, 80 Poised, abstract, nonconceptual, intentional content (PANIC), 176 maximal, 40, 99 Pot-and-statue example, 30–31, 31, 40, 48 PPC (principle of presentational occurrence), 89–90 Precise designator, 155–156 Present, specious. See Specious present(s) Presentational occurrence, principle of (PPC), 89–90 Presentness, 86 Psychological framework (PF), 141–143, 146, 148 and radical discontinuity between life stages, 150–152, 162 and split-brain transplant, 149–150 and teletransportation, 144, 145–148 Putnam, Hilary, 79 Qualia, hypotheses on of absent qualia, 8 of inverted qualia, 8
Index
Qualities in bodily experiences, 66 in “looks” talk, 169–172 and pain, 55, 179n.4 and phenomenal concepts, 168 and phenomenal succession, 101 phenomenal unity of, 36 direct and indirect, 100 unity as relation between, 102 Ramachandran, V. S., 61–62 Reactive disassociation, 56 Red-green flashes experiment (colored phi phenomenon), 90–91, 96–97 Red-square-and-green-triangle example, 39–40, 40–41 Reductive strong representationalism, 167 Referred pains, 54 Reid, Thomas, 140 Rene (multiple personality patient), 137–138, 138–139 Representationalism (representational approach), xvi, 84, 165–176 and bodily sensations, 61 and phantom limbs, 61 externalist, 167, 174–175 Fregean, 167–168 hybrid, 168, 169, 172–174 internalist, 167 Millian, 168, 172, 173, 174 and pain, 52–54, 64 representational content of, 58, 59 strong, 166 nonreductive, 167 reductive, 167 weak, 166 Represented order, vs. order of representations, 90
201
Responsive consciousness (R-consciousness), 6 as creature consciousness, 9 Reynolds, Mary, 138, 139, 141, 142 Rigid designator, 155 Roller-coaster/buried-alive example, 76–78, 118–119 Sacks, Oliver, body-image experience of, 45 Sejnowski, T., 91–92 Sellars, Wilfrid, 21 Sensation, bodily. See Bodily sensations Sensation, streamlike quality of, 85. See also Streams of consciousness Sense-datum theorists, 178n.4 Sequence of experiences. See Unity of experience through time Shoemaker, Sydney, 21 Simultaneous experiences, phenomenal unity of, 19. See also Synchronic phenomenal unity Single experience. See One experience view Sleep, and consciousness, 104, 182n.6 and dreaming (cases), 4, 10 and pain (case), 3, 7 Sleeping Dog, The (case), 4, 10–11 Smells, 69–70 Sounds, 69–70 Spatial unity, 12 Specious present(s), 87–92, 99–100 overlapping, 92–95 and phenomenal unity, 100 Sperry, Roger, 109 Split-brain patients, 109–113 and disunified access consciousness, 112, 121–125
202
Index
Split-brain patients (continued) and disunified phenomenal consciousness, 126–129, 134, 135 generally unified consciousness of, 126, 128–129 as indeterminate number of persons, 112, 117–120 and multiple personality disorder, 111–112, 113–116 and nontransitivity of phenomenal unity, 129–132 and Parfit on ego theory, 134, 135 and personal identity, 111–112, 115–117, 143–144 and phenomenal unity, 20 and simultaneous phenomenal disunification, 37 as unconscious automatons, 112, 117 and unity of experience through time, 102–104 Split-brain transplant example, 149–151 Star Trek television series, and teletransportation, 147 Statue-and-pot example, 30–31, 31, 40, 48 Strawson, Galen, 104–105, 107 Streamlike quality of sensation, 85 Streams of consciousness, 104–106, 107–108 and bundle theory of person, 139 Carnap on, 106–107 and split-brain patients, 104, 112–113, 126, 128 Strong representationalism, 166 nonreductive, 167 reductive, 167 Subjects of consciousness and action, persons as, 140, 143 Subject unity, 12–13 on bundle theory, 134 (see also Bundle theory of person)
on ego theory, 133 (see also Ego theory of person) higher-order, 13 Succession. See also Unity of experience through time experiencing of, 106 of feelings, vs. feeling of succession, 86, 102 phenomenal, 101 representation of, 101 Synchronic (of simultaneous experiences) phenomenal unity, 19, 35, 36–41, 84 Tastings, 58, 68–69 Technicolor phenomenology, 8 Teletransportation, 144–148 Thirst, 61 Thought(s) in auditory linguistic image, 72–73, 79–80 sequence of, 85 in unity with perceptual and bodily experiences, 78–81 Tickles, 60 Tingling sensations, 61 Torso and experience of here, 70 and general bodily feeling, 48–49 viewpoint related to, 71 Touch, 68–69 Transitivity, phenomenal unity’s lack of, 129–132 Twin Earth and PFs, 142 and phenomenology of occurrent thought, 79–80 Unconscious automaton, split-brain patient as, 112, 117 Unity of consciousness, 1
Index
Unity of experience, xiv of bodily experience, 49 problem of, 62–66 and handwriting example, 26 kinds of Gestalt unity, 13, 178n.10 introspective unity, 13, 20 neurophysiological unity, 12 object unity, 11–12, 19 phenomenal unity, 13, 15, 20, 36, 84, 107 (see also Phenomenal unity) subject unity, 12–13, 133, 134 Unity of experience through time, 95–101 and assumption of individual experiences, 107 examples of, 85–86 and Hume, 102, 105, 107, 133 and personal identity, 102–104 and presentness, 86 and specious present, 87–95, 99–100 and stream(s) of consciousness, 104–106, 107–108 Carnap on, 106–107 Unity of general bodily feeling, 47 Unity of perceptual and bodily experiences, occurrent thoughts, and moods, 67–68 conscious thoughts in, 78–81 and moods, 83–84 perceptual-body unity, 68–78 Unity of perceptual experience at a time and one experience view, 25–35, 39–40 (see also One experience view) as problem, 17–21 difficulties in, 21–25 and synchronic phenomenal unity, 36–41
203
Unity of persons, 133, 134. See also Person and personal identity Vagueness epistemic theorists on, 183–184n.3 in personal identity, 154–163 Vesuvius, Mount, as identity example, 30 Viewpoint, for vision, 71–72 Vision, and bodily experience, 70–72 Visual experience and beliefs, 175 and continuous consciousness (case), 4, 7 and introspection, 23–24 as unified experience, 28–35 viewpoint of, 71 Visual system, unifying function of, 11–12 Waterfall effect, 38 Weak representationalism, 166 Wiggins, David, 149 Wine Taster, The (case), 2–3, 6 Wine tasting, unity of experiences in, 18, 19, 27, 31, 32–33, 34–35 Writing example, for one experience view, 25–26 Zadeh, L., 160 Zombies, 9