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Part I concentrates on the most general constraints governing scientific theories of the mind, and develops the notion of a distinct mode of discourse, the language of the mind, which we ordinarily use to describe and explain our mental experiences, and which can be related only indirectly to the mode of discourse in which science is formulated. In Chapter 1, a position of ontological neutrality is developed, which allows us temporarily to suspend decision of what ultimate ontological or metaphysical shape our theory must take, materialistic, dualistic, interactionistic, vitalistic, etc. This allows certain sterile philosophical conundrums to be avoided, but leads directly to the most powerful challenge to unification in the theory of mind, the Intentionalist thesis that the mental mode of discourse is ultimately incompatible with the physical mode, and that no translations, reductions or unifications are logically possible. This challenge is examined in Chapter 2, and it is concluded that the best hope for unification lies with the development of a ‘centralist’ theory of mind. A centralist theory, in contrast to a peripheralist theory, would attempt to explain and predict human behaviour and experience by invoking central, internal states and conditions as crucial intervening variables in an explanation couched not in terms of mere stimulus and response, but in terms of purposive, conscious action. Chapter 3 determines some of the conditions of success for centralism and sketches a theory designed to meet these conditions. The essential task of centralism is seen to be justifying an interpretation of a physical system as a system whose states or events have meaning or content, and in Chapter 4 the conditions for such a justification are examined in detail, and the theory sketch is elaborated to meet these conditions. This leads to a general view of the relationship between the physical, mechanistic side of the story of the mind, and the non-mechanistic account embodied in our ordinary discourse about people.
In Part II, the bridge built in Part I is exploited in an analysis of consciousness, the feature of mind that is most resistant to absorption into the mechanistic picture of science. Chapter 5 gives a new account, based on the results of Part I, of the certainty of our introspective access to the ‘arena of consciousness’, and Chapter 6 analyses consciousness into several separable phenomena. Our ordinary view of consciousness is seen to be muddied by several sets of connotations that deserve separate treatment, and in Chapters 7, 8 and 9 these are given the attention they deserve. Chapter 10 shows that certain unavoidable imprecisions in the formulation of centralism are inherent in that part of our given conceptual scheme that deals with people and their minds. There is a recurring theme running through the book that traditional analyses, both philosophic and scientific, have failed by postulating unanalysed elements having the very capacities to be analysed, thus postponing true analysis.
My considerable debts to a small number of writers will be evident from the frequency with which their names appear in footnotes. Others have helped more directly by reading drafts and making suggestions. First, my thanks and admiration go to Gilbert Ryle, under whose tolerant supervision the ideas for this book first took shape, and whose always insightful comments led me gently back from many false starts. Then to B. A. Farrell, Nicholas MacIntosh and J. Z. Young, who provided early guidance into the literatures of psychology and neurophysiology, and A. J. Ayer, Dennis Stampe and Jeffrey Sicha, who forced a number of my philosophical ideas into clarity. More recently, my colleagues and students at Irvine have provided valuable assistance, in particular, Gordon Brittan, Karel Lambert, James McGaugh, Julian Feldman, and Frank McGuinness. Ted Honderich’s constructive criticisms of the penultimate draft led to many important revisions. I am indebted also to Henriette Underwood, Eva McCusker and Ida Brown for typing and excellent editorial suggestions beyond the call of duty. Part of my work on this book was supported by a grant from the University of California Humanities Institute, for which I wish to express my gratitude. I also wish to thank the editors of Behavioral Science, Journal of Philosophy and Philosophy and Phenomenological Research for permission to reprint with alterations parts of my articles published by them.
D.C.D.
Irvine, 1968
Part I
The Language of Mind
1
THE ONTOLOGICAL PROBLEM OF MIND
I THE MIND AND SCIENCE
Those who are convinced of the futility of philosophy are fond of pointing to its history and claiming that there is no progress to be discerned there. In no area of philosophy is this claim easier to support than in philosophy of mind, the history of which, when viewed through a wide-angle lens, appears to be a fruitless pendulum swing from Descartes’ dualism to Hobbes’ materialism, to Berkeley’s idealism, and then back to dualism, idealism and materialism, with a few ingenious but implausible adjustments and changes of terminology. The innovations of one generation have been rescinded by the next so that despite a growing intricacy of argument and a burgeoning vocabulary of abstruse jargon, supplemented in each era by the fashionable scientific terms of the day, there have been no real and permanent gains.
The question that defined the pendulum is what the relation is between mind and body, and the problem that set the pendulum in motion was Descartes’ dilemma of interaction. If, as seems plausible at first glance, there are minds and mental events on the one hand and bodies and physical events on the other, then these two spheres either interact or not. The initially reasonable suggestion that they do interact leads, however, to an impasse of such difficulty that it can be held to be the reductio ad absurdum of dualism, at least of the Cartesian variety. If, ex hypothesi, mental events are non-physical, they can involve no physical energy or mass, and hence cannot in any way bring about changes in the physical world, unless we are to abandon the utterly central principle of conservation of energy and all its ramifications. Something must give way in this dilemma, and there are many choices available, all traced out by the swings of the pendulum. One can abandon the principle of conservation of energy, and this gives rise to the family of views of non-physical causes and ‘occasions’; or one can preserve the principle and deny one of the other steps that lead to the dilemma. That is, one can deny that there are bodies and physical events and be an idealist, or deny that there are non-physical minds and mental events and be a materialist or physicalist, or hold for a dualism without interaction, and be a parallelist or epiphenomenalist.
The deficiencies of each of these alternatives, in each of their variations, have been well demonstrated time and again, but this failure of philosophers to find a satisfactory resting spot for the pendulum had few if any implications outside philosophy until recent years, when the developments in science, especially in biology and psychology, brought the philosophical question closer to scientific questions – or, more precisely, brought scientists closer to needing answers to the questions that had heretofore been the isolated and exclusive province of philosophy. Although one can still find in the current literature of the neurologists the old disclaimers about ‘leaving to the philosophers’ the ‘mysteries’ of consciousness, the ‘initiation by the mind of neural activities’ and so forth, these efforts to skirt the difficult questions are no longer satisfactory. We need answers now not only to the ‘strictly philosophical’ conceptual questions of mind, but to the still quite abstract questions that bridge the gap between physiological theory and the philosophical understanding of mental concepts.
This gradual and hard-won approach of science to the philosophical questions of the mind-body problem has led to a reshaping by some philosophers of the central concern of the philosophy of mind. In deference to the development of science in the area, they take the task to be providing a satisfactory status for minds and mental events relative to the scientific corpus, and quite naturally their favoured solution to the problem is the identification of mental entities with physical entities.1 The motive for this identification can be roughly characterized as falling in the same class as the motive for identifying flying saucers with swamp gas, or mermaids with manatees: to avoid ontic bulge.
To suppose that there are flying saucers or mermaids in addition to the more ordinary things we hold to exist is to force an inelegant and inexplicable bulge in the shape of our scientific image of the universe, and would eventually force an entirely unwanted revision in some fundamental and otherwise acceptable laws and principles of the natural sciences. Similarly, these philosophers have feared that the assumption of explicitly non-physical mental things – such as thoughts, minds, and sensations – jeopardizes in a more serious way the integrity and universality of the going scientific scheme. Putting their faith in the going scheme, they have determined to identify mental things with, or ‘reduce’ them to, physical things.
They see as the only alternatives either an asymmetrical scientific picture which includes, in one small corner of the universe, basically different, non-physical entities which do not fall under the laws of physics and thus force either drastic changes in these laws or an unsatisfying abridgment of their universality; or the prospect of discovering or proving these mental entities and events to be nothing more than some as yet undescribed physical entities and events, presumably in the brain. If they are right in supposing these to be the only available alternatives, then the attempt to reduce away the offending mental things is certainly the more reasonable first avenue, just as one should turn to hypotheses about spacemen, fifth dimensions and anti-gravity machines only after all attempts to identify flying saucers with more mundane entities have failed. Unfortunately, the plausibility of the identity theory derives almost entirely from the implausibility of its alternative; if the dangers in denying it did not seem so patent, few would be inclined to suppose that a thought or a pain or a desire just was a brain process. In this respect modern identity theory looks all too much like its materialistic predecessors on the pendulum swing: a meta-physically extravagant and implausible monism into which one is driven by the recognition of the dilemmas in equally extravagant and implausible dualisms. The identity theory, I shall argue, is wrong, but this does not force us back on to any of the old dualisms, which are equally hopeless. The way out of this unpromising situation is to get off the pendulum entirely, and this involves showing that one of our initial assumptions is not so obvious as it first appears, viz., the assumption that there are minds and mental events on the one hand and bodies and physical events on the other.
II EXISTENCE AND IDENTITY
The strategy that promises to break the spell of the old isms was first exploited by Ryle in The Concept of Mind.2 Ryle argued that mind and matter were in different logical ‘categories’, and since they were in different categories there was something logically or conceptually otiose in attempts to identify mind with matter, or in worrying when these attempts failed, as they must. This line is attractive if it can be made to work: it excuses the identity theorist from his dubious task and tells us at the same time that fear of an ontic bulge is misplaced in this instance. The conceptual elbow room it provides, however, must not be taken to establish the plausibility of its premises. Is there in fact any logical or conceptual distinction between mental entity terms and physical entity terms that could be used to justify the claim that the identity theory is a ‘category mistake’?
Illustrations of the sort of differences needed to sustain this sort of claim are not hard to find. Common nouns in English exhibit marked differences in the ranges of verbal contexts in which they can properly, significantly appear. For example, although ‘sit on the table’, ‘sell a table’, ‘covet that table’ and ‘cut the table in half’ are all unexceptional, there is something wrong with ‘sit on the opportunity’, ‘sell a twinkle in the eye’, ‘covet the cube root of seven’ and ‘cut the acquittal in half’.3 By and large, words for everyday middle-sized objects fit in the greatest variety of contexts while ‘abstract’ and ‘theoretical’ words are the most restricted. Probably our native ontological bias in favour of the concrete over the abstract derives from this difference in contextual scope; the more contexts a noun is at home in, the more real, thinglike, and familiar the entity seems. (It should be possible to confirm this bit of speculation about our intuitions and preferences, but confirmation would be irrelevant to our undertaking; no substantive ontological questions could be settled by appeal to public opinion polls.) There are a few extreme cases in English of nouns restricted to a mere handful of contexts, or even just one. Quine mentions ‘sake’ in ‘for the sake of’ and ‘behalf’ in ‘on my behalf’.4 Other such idioms are ‘by dint of’ and ‘plight one’s troth’. You cannot do anything with or against anyone’s sake, nor can you hope for a behalf, avoid a dint, or watch over one’s troth. As Quine points out, these degenerate nouns have no combinatory function on their own but are locked into their idioms. The whole idiom functions as one word, and there are really only etymological and aesthetic reasons for dividing the idioms typographically at all. This means that any logical or semantical analysis of ‘for my sake’ or ‘on my behalf’ based on the similarities these share with ‘for my wife’ and ‘on my head’ would be an error bred of unfamiliarity with the language. Anyone foolish enough to search a house in an effort to find its owner’s sake, or to attempt to identify a man’s behalf with his body temperature or bank balance would be making an error akin to that of the man who expects a van in each caravan, wonders where the ward is when one marches forward, or expects an audible clank when the dying man finally kicks the bucket. In these cases the Rylean argument is obvious: e.g., it would be a category mistake for the physiologist to try to isolate and identify the dint of certain muscular exertions, which does not mean that a dint is a secret, non-physical accompaniment to those exertions.
Similar arguments can be made for less extreme cases. Quine suggests that nouns for units of measure, such as ‘mile’ and ‘degree Fahrenheit’, are best viewed as integral parts of a small group of idioms rather than as full-fledged nouns which pick out distinguishable items in the world.5 Once the modern materialist recognizes the limits English places on ‘mile’, he will not be disturbed by the realization that the miles between the earth and the moon are not to be identified with any intervening rays, atoms or trails of plasma.6
If these trivial cases of category mistakes are well established, their very triviality may seem to weigh against the plausibility of any analogy that would ally them to the rich and versatile vocabulary of the mind. Thoughts and pains and desires seem to have a much more robust existence than sakes and miles; although one cannot see or spill ink on a thought or a pain or a desire, a thought – like an explosion – can happen; a pain – like a flame – can be intense; and a desire – like a piece of garlic – can cause an upset stomach. If the analogy between such terms and our trivial examples is strong enough both to bar and excuse them from the crucial identity contexts, this is far from obvious. Certainly it has not been obvious to the many writers who have attempted to defend versions of the identity theory in the last decade.
What is not obvious may nevertheless be shown in the end to be justified, or at least worth investigating. Consider one more example, closer to the problems of mind in its complexity but without the burden of ancient mysteries. We say ‘I hear a voice’, ‘he has a tenor voice’, ‘you’ll strain your voice’ and ‘I have lost my voice’. Now is a voice a thing? If so, just what thing is a voice? The voice we strain may seem to be as unproblematic a physical part of the body as the back or eyes we strain, perhaps the vocal cords; but surely one does not have tenor vocal cords or enjoy Sutherland’s vocal cords, or lose one’s vocal cords, and one’s voice, unlike one’s vocal cords, can be sent by radio across the seas and survive one’s death on magnetic tape. Nor does one strain or recognize or lose any vibrations in the air or manifold of frequencies. It might be argued that ‘voice’ is ambiguous – perhaps with some neat and finite list of meanings, so that the voice that changes or is strained is a part of the body, and the voice one enjoys or recognizes or records is some complex of vibrations. Then what is the voice one loses? A disposition, perhaps. Dividing the wor
d into these different senses, however, leads us into ludicrous positions: Sutherland’s voice on the record is not (numerically) the same voice as the one she strained last month, and the voice that is temporarily lost is not the voice we recognize. How many voices does Sutherland have? If we took this claim of ambiguity seriously, the sentence ‘Sutherland’s voice is so strong; listen to the purity of it in this recording of it that I made before she lost it’ would be a grammatical horror, with each ‘it’ in need of a different missing antecedent, but there is obviously nothing wrong with the sentence aside from a bit of repetitiveness. When the word is viewed (correctly) as unambiguous, attempts to delineate any portion or portions of the physical world which make up a voice will be fruitless – but also pointless. A voice is not an organ, disposition, process, event, capacity or – as one dictionary has it – a ‘sound uttered by the mouth’. The word ‘voice’ as it is discovered in its own peculiar environment of contexts, does not fit neatly the physical, non-physical dichotomy that so upsets the identity theorist, but it is not for that reason a vague or ambiguous or otherwise unsatisfactory word. This state of affairs should not lead anyone to become a Cartesian dualist with respect to voices; let us try not to invent a voice-throat problem to go along with the mind-body problem. Nor should anyone set himself the task of being an identity theorist with respect to voices. No plausible materialism or physicalism would demand it. It will be enough if all the things we say about voices can be paraphrased into, explained by, or otherwise related to statements about only physical things. So long as such an explanation leaves no distinction or phenomenon unaccounted for, physicalism with regard to voices can be preserved – without identification of voices with physical things.