The philosophy of mind is a branch of the philosophy of nature. But it has this peculiarity, that the very item that conjures up its questions and vets its answers is the very part of nature under investigation. And it has the added peculiarity that its subject is the mind. A system that can harbour such natural marvels as imagery of what is long past, thoughts of what never even managed to be, and dreams of the logically impossible, in this subject turns its philosophical attention onto itself. In these special circumstances one might expect a few rules to go by the board. In any case, they do. The philosophy of mind is something of an exception to a rule or maxim limiting our legitimate metaphysical expectations: roughly, a rule to the effect that we should expect little or nothing. Now it is well-known that philosophers have long abandoned all pretensions to the role of cosmological sage, of a priori astronomer charting a heaven of ideas, and that this was effected through a sceptical critique that emanated from its own ranks: above all, from Hume, Kant and Wittgenstein. A sort of pessimism with regard to metaphysical enterprise seems as a result to have set in at some point, which lingers to this day, in which I suppose we are still paying for the brilliant excesses of our romantic metaphysical forefathers, and of Hegel most of all. Those ‘intellectual inebriates’, in the eyes of some, have bequeathed as our lot a seemingly permanent condition of metaphysical sobriety and philosophical self-consciousness.
Now there can be little doubt that the self-consciousness has been a gain, but even less doubt that the sobriety has gone too far. This victory of self-awareness over natural wonder betokens something closely akin to guilt. Dropping onto their knees before the harsh god physics, fellow-travellers of the physical sciences, as it were, many 20th-century philosophers have been only too ready not only to put metaphysics and even philosophy in the dock, but (in a moment of suicidal madness) the very mind itself along with them. For in one way or another the stocks of these three items have tended to move in parallel in our subject, either in earlier periods of rampant manic excess or in the recent drawn-out era of depressive self-effacement.
The philosophy of mind in its latterday form is, I suggest, one of the chief deliverers from this tyranny of the merely and only physical. Everywhere one looks in this subject it is possible to strike metaphysical oil. Whether the topic is the imagination, thought, the will or the self, an a priori investigation can be set up that stands a good chance of emerging with startling results. It is a double irony that one of the more startling of these results, and in any case the thesis of widest scope, is the metaphysical theory of ‘physicalism’. There was a time when adherents of this doctrine affirmed it as a scientific hypothesis, to be established slowly and painfully by the systematic success of physical scientific procedure, rather in the way the doctrine of vitalism found itself gradually removed from the books. Probably this view still has its supporters today. But not many. If, as seems rather likely, some watered-down non-reductionist materialism proves to be the truth of the mind-body relation, few any longer doubt that the arguments in its favour will be found in philosophy rather than the physical sciences. (Donald Davidson has already made a determined attempt in that direction.) And that is to say that its metaphysical status is more or less acknowledged.
In short, metaphysics may at the moment lay claim to the mind at its natural and favoured proving-ground: so to say, in lieu of The Universe as a whole: contracting into a microcosm. In its own small way, this signals a return to content in a subject which has over long been exclusively preoccupied with matters of form, and in a novel mode which owes everything to those preoccupations. This transformation of outlook is, I believe, largely the work of one man, Wittgenstein. It is true that he above all others helped generate the climate of philosophical self-consciousness in which philosophers have sweated for some fifty years; yet paradoxically, his later work, and above all his writings and classes in Cambridge in the 1940s, opened up the philosophy of mind to an entirely new degree. Doubtless he would not have wished to call it ‘metaphysics’; but it was a conceptual and it was not a scientific investigation, and it abounded with substantive philosophical insights into the nature of mental phenomena. For my money, that is a kind of metaphysics. It is the metaphysics of the most highly developed natural phenomenon of this or any conceivable phenomenal world. In any case, he fathered the subject as we know it today in Anglo-American philosophy. Since his death in 1951, there have been important advances on a number of major questions: the mind-body problem and action theory stand, I think, in the forefront, but also to a significant degree the self and thought and sense-perception (though it must be said of the latter that the ‘advance’ has mostly consisted in beating a judicious retreat to traditional views from the improbable positions occupied between 1930 and 1960 – also, it may be, under the influence of Wittgenstein!).
Colin McGinn’s admirable book manages to give a comprehensive picture of the state of play in the subject at the present time. In a compressed and well-written work, and without any loss of subtlety, he contrives to lead the reader on a guided tour of the problems listed above. He has chosen to present theories rather than theorists, intentionally suppressing all references to their originators and champions (except in the preface, where due acknowledgments are made), in order that the philosophy may speak for itself, unhampered by polemicism and other distractions. This format is entirely successful. The result is a lucid and impressive discussion of the issues in their own right. And it should be added that at all times McGinn’s own contributions to the problem under discussion are noteworthy, as is the judiciousness and philosophical sensitivity with which he weighs the pros and cons of the various theories that he sets forth for our consideration.
I will confine my comments to what McGinn has to say about perception and the self. His discussion of perception divides – interestingly and properly, it seems to me – into acquaintance with external physical objects, one’s body, oneself, and the contents of one’s mind. For these epistemological situations are irreducibly diverse. Concerning perception of external objects, he puts his finger on something that coheres marvellously well with the fact that in sense perception we sensuously encounter no more than a flimsy few superficial properties – as it were, a mere covering skin, constituting the appearance of the item, and that it is an essential property of an appearance that it might be of a different individual and of a different type. It is precisely the aforementioned skimpiness and shareability that ensures that the intellect always has room for manoeuvre in and after sense perception. What McGinn draws attention to is that the contributions of sense perceptions to experience, while going beyond sheer sense, being inevitably determined causally by the intellect as well, are almost entirely general. Thus, ‘he seems to see something with the look of Mr X’ is truer to the perceptual facts than ‘he seems to see Mr X,’ even though he truly sees and seems to see exactly Mr X. Somehow the seeing of Mr X as Mr X is not merely ‘extra’-sense but ‘extra’-sense-perceptual too. This is a fine and important point.
On the issue of representationalism, McGinn seems to me to be mistaken. He rightly rejects the idea that perceptual experiences are ‘little pictures in the mind’, noting that ‘we do not become acquainted with the objects of perception by looking at experiences,’ but to my way of thinking proceeds to throw the baby out with this undoubted bathwater. Thus he claims that no more than three items are involved in the sense-perceptual situation: perceiver, object, experience. But if we import the distinctions, Experience/Psychological Object of Experience and Representational Image/Naturalistic Image, we will, I believe, stumble upon a fourth. We encounter something that is image, experienced, and such that we become acquainted with the objects of perception by becoming acquainted with it. I mean, the perceptual sensation (what puts the ‘sense’ in ‘sense perception’). This is an entity that lives between wind and water in the philosophical mind. It has long seemed to me that the very first question in sense perception is the reality or not of the sensation. Yet again and again we find philosophers in one and the same breath speaking of visual sensations and asking whether sense-data exist! Their position and their language are inchoate. And yet visual sensations exist. What else are after-images? But if they exist at all, they exist all the time in sense experience. To be sure, we do not look at visual sensations, nor do we attend to them in opposition to what they present to view, and they no more represent what they image than does a shadow; but there can be little doubt that one’s attention is caught by them, for their colour is that of the seen physical occupant of their part of the visual field. I can scarcely prove this here, but convincing causal considerations can, I think, be advanced for believing in their existence. Here I wish merely to show that they elude McGinn’s critique.
Perhaps the most impressive part of the book is the discussion of the self. McGinn approaches this topic in a novel way, suggesting that we interpret the familiar enough search for criteria of personal identity as in effect an inquiry into the nature of the self. The exposition that follows of the several possible theories of the self, and the difficulties that they must each face, is extremely skilful and very sure. But ‘who’ are these selves of which he speaks? The answer is that they are whatever is a ‘who’: in other words, what the philosophical tradition calls persons. McGinn is not prepared to grant selves to non-rational beings, for the reason that they lack ‘centres of consciousness’. It seems that, while allowing that human persons must be accounted animals, he considers that persons constitute a new and I daresay a higher philosophical phenomenon on the world’s stage. Then what constitutes the nature of those animals that manage to achieve a higher ontological status than their dumb brethren? Apparently the answer, rational animal, while true, is not open to us, for reasons which are not obvious to me. McGinn instead opts for a doctrine that owes something to Strawson and, it may be, Kripke: namely, that just as there are no constitutive criteria for the identity of material objects, so none exist for the self. His conclusion, that the self is a simple indivisible substance, is defended by showing that no mental or physical criteria are available for personal identity; and leads him to the important and surprising thesis that the common assumption that there exist such criteria is tantamount to an endorsement of a reductive metaphysic of the self.
All this is very ably carried through. But a difficulty lingers, at least for me. I shall lead up to that difficulty in stages. Thus, precisely those arguments that tell against mental or physical analyses of selfhood count equally powerfully against similar theories of animality. Then are animals also simple indivisible substances? Perhaps. In any case, they look to have as strong a claim to the title as do persons. But McGinn wishes to make a more ambilious and more exciting claim on behalf of the self. It is that the concept of the self is a mental concept. Selves are of course ‘enmattered’ – even, he suggests, possibly necessarily so. But just as the concept of a dream is a mental concept, although dreams may find incarnation in brain phenomena, so it is with selves. By now the self is beginning to look like a soul, albeit one with feet of clay; and we are not all that remote from Descartes: Descartes without dualism, if one can imagine such a thing. I see nothing pernicious in such a suggestion. And it is not quite so counter to the spirit of contemporary thought as some might imagine. Many a physicalist is a Cartesian at heart, and physicalism has been instrumental in ‘smoking out’ some of the virtues of Cartesianism that a behaviourist era had forgotten. Still, we need arguments if we are to follow McGinn all the way to this conclusion, and, doubtless for reasons of space, they are not really given. All the more necessary it seems if one remembers that the only selves that we are ever likely to encounter are animal to the core. (And you can say that again.) Then the difficulty that I experience is this. That if selves are mental, and selves can also be animal, might we not have to say that the concept of animality is likewise mental? But is the concept of a flea the concept of a mental entity? It is true that Blake saw fit to depict ‘the soul of flea’, and possibly not out of sheer zaniness; but there can be no doubt that the idea is problematic. This is a difficulty for McGinn’s position, though it may well be surmountable. After all, the life of the brain is probably as necessary and sufficient for the being of any animal as it is for that of persons that are animal; and that suggests that animality may be a (necessarily incarnate) mental type phenomenon. This is a fascinating discussion, to be recommended to students and professionals alike.
One last comment – on the philosophicalness of this work of philosophy. Nowadays one encounters much intelligent work which, while carried out legitimately enough under that head, gives one the feel that its author might very easily have laboured in any of half a dozen disciplines. This is scarcely imaginable of art, and it should not really be possible in the case of such an ancient subject as philosophy. It is a subject that arose out of a primeval form of natural wonder that comes to fruition in an enterprise in which the desire to understand fights with a continuing sensitivity to the autonomous mystery of its subject-matter. If science is a hunter, philosophy is at once hunter and conservationist. Both forces are well represented in McGinn. Natural wonder rather than mystification, the desire to explain and connect rather than the drive to reduce: that is what one finds on every page of this brilliant book.