Physicalism

K. V. Wilkes

• Publisher: Routledge
• Year: 2014
• Print ISBN: 9781138825956
• eBook ISBN: 9781317577393
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

The primary aim of this study is to dissolve the mind-body problem. It shows how the 'problem' separates into two distinct sets of issues, concerning ontology on the one hand, and explanation on the other, and argues that explanation – whether or not human behaviour can be explained in physical terms – is the more crucial.

The author contends that a functionalist methodology in psychology and neurophysiology will prove adequate to explain human behaviour. Defence of this thesis requires: an examination of the mental/physical dichotomy, and its rejection in favour of a distinction between psychological and physical terms; a description and discussion of functionalism in psychology and neurophysiology, showing how the notorious problem of the necessary intensionality of psychological terms may be circumvented; an examination of the role of computer simulation in psycho-physical research; and an explanation of how the phenomena of sentience fit the functional framework.

The book concludes that the thesis presented is in all essentials that of Aristotle; Aristotle had no 'mind-body problem', and were it not for a subsequent over-obsession with Cartesian scepticism, we need not have had one either.

CHAPTER 1

RELATIONS AND RELATA

TO begin with an outstanding banality: the mind-body problem is the problem of the relationship between mind and body. This platitude has the single merit of making explicit the fact that we have here a two-termed relation, which may be schematised as ‘aRb’; in which ‘a’ stands for whatever ‘mind’ stands for, ‘b’ does the same for ‘body’ and ‘R’ is proxy for the relation or relations that hold between the two. We have then on the face of it three candidate objects of study: each of the relata, and the relationship itself. Although it is the relationship that has borne the main brunt of philosophical investigation, we may find that it is as difficult to pin-point genuine relata as it is to disentangle the nature of the links holding between them.

At the outset, it is clear that the terms ‘mind’ and ‘body’ are themselves stand-ins for something more explicit. They are summarising labels; and what they summarise are normally taken to be, on the one hand, mental, and on the other, physical, events, states, and processes. Supposing, then, that these are the relata, how clear are they? For our present purposes the scope of the term ‘physical’ is relatively unproblematic. All we need say about it at the moment is that the expression ‘the physical’ picks out all and only the items, processes, concepts, laws, hypotheses, theories, or theoretical postulates used essentially by physical scientists. Any concept, therefore, which plays some significant role in a theory belonging to the physical sciences is eo ipso a physical concept. This means that it is no business of the philosopher layman to predict or restrict the conceptual elements in the framework of a science: he must accept as ‘physical’ whatever the physical scientist says is such. Certainly the philosopher of science may need to query or challenge various features of the theory, including elements of its conceptual apparatus. But the philosophy of physics is not our present concern: just now we should simply note that the scope of ‘the physical’ is the physical scientist’s business.

On the physical side of the mind-body relation, then, there seems no bar in principle to the suggestion that the physical sciences which study the brain and human activity can have or devise a vocabulary adequate for the identification of any physical event, state, or process. We shall return eventually to a more detailed and comprehensive view of the physical; for the moment this will suffice. What of the other term of the relation, ‘the mental’? This is much less clear. Unlike the physical, which can as we have seen be strictly delimited by the rather blank consideration that all and only the terms featuring essentially in the description of physical theories count as ‘physical’, the mental cannot be clearly described in a correspondingly neat manner. We have an intuitive idea of the range of the notion, derived from our regular everyday handling of many of the terms which comprise the category – but is there not something more clear-cut than intuition ?

It would be easy and tempting to object at this point that there is no need to search for any criterion of the mental. Intuition alone would serve quite well: we tend to agree, after all, about what are and what are not mental terms. Indeed there might be no criterion to distinguish the mental from the non-mental, and yet this would present no obstacle either to the validity of the term ‘mental’ or to our claim of mastery over the concept: this has been conclusively established by Wittgensteins discussion of family-resemblance terms. Now this objection is persuasive. It must be granted that we can handle mental terms with adequate facility, and usually have little doubt about our classification of phenomena as mental or not. Nevertheless the suggestion that we should rely exclusively upon intuition and convention to delimit the scope of the mental will not do, for the following reasons:

(1) First and most powerfully, there may prove to be no worth-while or valid distinction at all to be drawn between mental and physical; in other words, the dichotomy may be a false one. However implausible this suggestion may seem at first sight, it is one aim of this work to exploit it; to make it more palatable now, I shall simply assert that the Greeks have no such cleavage – had nothing even approximately equivalent to it (see chapter 7).

(2) Although we have a sure mastery of most mental concepts most of the time, we may be at a loss if required to label as ‘mental’ or ‘non-mental’ some very common and everyday terms. Several seem to hover in between mental and physical status, being a bit of both: ‘nervous’, ‘asleep’, ‘unconscious’ or ‘dazed’ are examples of predicates which are not clearly mental rather than physical, nor vice versa. Similarly, although ‘thinking’ seems indisputably mental, what of ‘concluding’ or ‘contradicting’? We should rightly become impatient if pressed to give a definite answer to the question ‘Mental or not ?’ asked of such terms; but to avoid such tedious questioning successfully, it would help to be able to say what is significant and essential about clearly mental concepts, and hence to explain what is – or isn’t – mental about these apparent hybrids.

(3) Everyday mental concepts are not the only ones with which we must deal. The advance of the psychological sciences has opened up a wide and rough terrain of disputable cases. Drives; stimulus inputs; information retrieval mechanisms; the id-ego-superego triad; libido; unconscious, subconcious, and preconscious events and processes – any terms such as these will be tricky and perplexing to one seeking to delimit the mental by intuition, resisting neat (or even rough) categorisation as mental or non-mental.

(4) We are already attributing to computers a large number of mentalistic concepts; add a dash of science fiction, and we find machines to which we may need to attribute yet more. Now even if we insist – for whatever reason – that a computer cannot add, but can only ‘add’, or, in short, that whatever mental term ϕ we take, computers can only ‘ϕ’and never ϕ , we need to justify our use of the insulating quotation marks. And to justify them, we would have to say what it is about human ϕ -ing that is missing from computer ‘ϕ -ing’; that is, we must explain what is peculiarly mental about (ϕ -ing. If on the other hand we were to allow that computers can indeed ϕ without the insulating quotes, then we can pertinently be asked why ϕ -ing is after all to be considered a mental rather than a physical process; this might return us to the first argument in reply to the objection: namely, is the mental – physical dichotomy really genuine?

Thus all things considered it seems necessary to try to characterise the mental more definitively; and if the attempt ends in failure, this too will be instructive and important. In fact there are available two popular theses, each of which is said to distinguish the mental from the physical.

The first of them, which I shall for convenience label ‘the incorrigibility thesis’, draws the distinction in terms of our special epistemological position vis-à-vis our mental events. It claims that mental phenomena are such that whoever has them is immediately aware of them; that they are private to their owner so that he has a privileged access to them; in short, that we are incorrigible about our own mental events in the sense that nobody could conceivably be thought mistaken if ever he sincerely asserted that he was, or was not, experiencing a particular mental phenomenon. This line of thought has been highly popular ever since Descartes.

There are two main flaws which mar any formulation of the incorrigibility thesis. The first, which will be discussed in greater detail later, is due to the vagueness and ambiguity of the terms used. Ayer has picked out no less than four senses of ‘private’,¹ and there may be more;² and none of these interpretations of the term, on examination, can justify or explain our alleged incorrigibility in respect of the private entities. ‘Immediate awareness’ is a notion which has been forcibly attacked by many discussions of sense-datum theories; and it looks extremely unlikely that we can characterise the objects of this special awareness in non-circular fashion – the objects of immediate awareness are just those things we are incorrigible about, and we are incorrigible about all and only the objects of immediate awareness. The kind of incorrigibility in question cannot be elucidated independently of these other suspect notions.³ Nevertheless, we need not now linger over this particular flaw of the incorrigibility thesis: we shall be returning to it, and there is another difficulty which is clearer yet. The second drawback to the thesis is that the characterisation of the mental it suggests leaves out much that by intuition and common sense we would unhesitatingly include in the category. One who is self-deceived, for example, must be credited with beliefs and desires to which he would not admit he subscribed – we cannot make sense of the fact of self-deception otherwise. Again, the suggested criterion fails to cope with some emotions like anger – one can furiously but sincerely deny one is angry. The thesis further excludes moods and dispositions such as vanity, generosity, irritability and the like – for often we have no immediate awareness of these but, on the contrary, may be the last to realise we are vain, generous, or irritable. Moreover, it debars from mental status all preconscious, subconscious, and unconscious mental states or events. Perhaps most tellingly of all, it even excludes some mental phenomena which are conventionally seen as very paradigms of this criterion. Pains and after-images are popular illustrations of phenomena of which we are infallibly and immediately aware – yet there have recently appeared convincing arguments to suggest that it can make excellent sense to talk of pains of which one is not aware,⁴ and certainly I may be unaware of an after-image if I am looking at a wall of the same shade against which it is invisible.

In sum, the incorrigibility thesis makes one rather imprecise point about many mental happenings, which needs considerable clarification and qualification before it is accepted: that the one who has the mental state in question often also has a privileged epistemological position in relation to it. But it cannot serve to give us any criterion of the mental.

The second view purporting to mark off the mental from the physical I shall call ‘the intensionality thesis’. It may be useful to give a rough outline of what intensionality is before assessing the thesis. We can select three main criteria for distinguishing intensional from non-intensional sentences:

(A) The first criterion treats sentences whose main verb takes a direct object. Such a sentence is intensional if the existence or non-existence of the item picked out by the direct-object phrase makes no difference to the truth values either of the sentence itself, or its negation. For example, The Greeks worshipped Zeus’, and The Christians worship Jesus Christ’, and the negations of those sentences, are alike true or false quite independently of any judgments we may make about the existence of Zeus or Jesus ; so is ‘Pooh hunted hippogriffs’ But ‘The Jews crucified Jesus Christ’, and ‘Pooh caught a hippogriff’ are not intensional sentences; for they would be falsified by the non-existence of Jesus Christ or hippogriffs.

(B) The second criterion treats sentences whose main verb governs a propositional clause. Such a sentence will be intensional if the truth value of the contained sentence does not affect the truth values of the containing sentence and its negation. For example, ‘Pooh hopes that a hippogriff will fall into his trap’, and ‘The Trojans believed that the wooden horse was harmless’ are intensional by this criterion; the truth values of ‘A hippogriff will fall into Pooh’s trap’, and ‘The wooden horse was harmless’ may vary without varying the truth values of the whole sentences. But it is true that the wooden horse was harmless’, and it is a fact that Pooh caught a hippogriff are not intensional; both are falsified by the falsity of the contained propositions.

(C) The third criterion treats sentences with main verbs of either kind. Take any set of pairs of descriptions in which each pair denotes the same thing; and take any sentence where the object of the verb, whether direct or propositional, includes in its description one member of such a pair. Then a sentence is intensional if the substitution of the other member of the pair for the first may affect the truth values of the complete sentence and its negation. Suppose that the expression ‘the wooden horse’, and ‘the booby-trap prepared by the Greeks to take Troy’ pick out the same object. Then although ‘The Trojans believed the wooden horse was harmless’ is probably true, ‘The Trojans believed that the booby-trap prepared by the Greeks to take Troy was harmless’ is certainly false. The truth value of non-intensional sentences, however, remains unaffected by such substitutions; they all obey the compelling principle that reference-preserving substitutions in a sentence preserve its truth value. Hence, if ‘Cicero denounced Catiline’ is true, then so must be ‘Cicero denounced a man who was praetor in 68 BC.’

These three criteria spell out what Brentano called the ‘Intentional Inexistence’ of mental phenomena, such as believing, wishing, hoping, fearing, and the like;⁵ their objects, whether substantial or propositional, need not exist or be the case in the real world. To use intensionality as a mark of the mental is to make the claim that whenever we are describing or explaining mental phenomena we have to use intensional sentences, whereas when we are describing physical phenomena any intensional sentence we happen to use will prove eliminable.

Now intensionality is not wholly adequate as a mark of the mental. Some intensional sentences are clearly non-mentalnotoriously those involving modal operators, like ‘It is possible that p’, and ‘It is necessarily true that p’. Conversely, some clearly mental sentences do not fit the thesis very readily: ‘John has a pain’ is not itself obviously intensional, and it is unclear that it must emerge as intensional even under a fuller description or explanation (it is interesting that the mental phenomena claimed to fit the incorrigibility thesis best, fit the intensionality thesis least well, and vice versa). Nevertheless, with a few such qualifications, we should admit that intensionality is a feature of a great number of sentences ascribing mental states to people; and t...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Original Title Page
• Original Copyright Page
• Table of Contents
• Dedication
• Acknowledgments
• 1 Relations and Relata
• 2 Intensionality and Irreducibility
• 3 Psychology and 'psychology'
• 4 Psychology and Practice
• 5 Robots and Research
• 6 Sensations and Sentience
• 7 Mind Undermined
• Bibliography
• Index