13 OCTOBER 2007, Page 31

• • Moving between philosophy and science

Michael Tanner THE STUFF OF THOUGHT by Steven Pinker Allen Lane, £25, pp. 499, ISBN 9780713997415 © £20 (plus £2.45 p&p) 0870 429 6655 This is the latest in the longrunning series of popular books that Steven Pinker, a professor in the Psychology Department at Harvard, has written about the human mind, particularly about the nature of thought and its relationship to language. Pinker is extremely interested not only in the nature of language, and the way in which languages work, but also in lots of odd or striking things about languages. As part of his attempt to make some highly complex and abstract ideas comprehensible and even attractive, he uses a huge number of examples. Sometimes you feel that his hope is that even if you don't quite cotton on to his theoretical positions, at least you will enjoy the quotations, jokes, even illustrations, that he bombards you with. He has a chapter, for instance, called 'The Seven Words You Can't Say on Television,' in which he discusses the nature of taboo words, which subjects they are likely to occur in, why it is that the same thing can be called by one word that is decent and another is obscene, how some areas that used to be considered out of bounds no longer are, and many other topics. It's a 50-page chapter, so there is plenty of room for long lists, for comparison of taboo words in different languages, for a consideration of which part of the brain comes into operation when you swear, and much more. I find that Pinker writes on this, and on all the other issues in the book, in a way that makes any page selected at random absorbing reading, but that as you go on you begin to wish that he would cut out many of the examples and let you think harder about what more general point they are supposed to be helping to make.

He begins by pointing out that we should be more surprised than we usually are by the speed with which small children not only learn to talk, but also the rate at which they absorb many rules of language which no one tells them about, and which are quite subtle. For instance, we can say 'Hal loaded the wagon with hay,' and 'Hal loaded hay into the wagon,' but we can't say 'Bobby filled water into the glass,' though we can say 'Bobby filled the glass with water.' Why is it that we can say some of these things and not others, and how is it that it's very rare for children to make mistakes in this area, even though no one explains the asymmetries to them? And moving on from here, Pinker provides countless cases of learners grasping language without being instructed in it. What is it about our minds that enables us to achieve these remarkable results? It's at this point that Pinker often moves between philosophical and scientific questions, not seeming to realise their difference. He only mentions Wittgenstein once, despite his huge contributions to the philosophy of language, and Donald Davidson not at all. These men, and other philosophers, don't, of course, explain how things happen in the world, but they do give accounts — disputable ones — of, for instance, what it is to possess a concept, and where we may be misled into thinking that there is a problem when there isn't one. They avoid saying things like, 'My brain tells my hand to move' as an explanation of how I raise my hand, because they realise that my brain doesn't 'tell' my hand to do anything: brains aren't the kind of things that issue orders. But Pinker does say that, because he hasn't bothered to differentiate the question of what physiological and neurological activities are involved in my raising my hand, and the question 'How do I raise my hand?' as it might be asked by someone who wondered what the connection is between wanting to do something with a part of my body and actually doing it. He would probably regard such a distinction as hair-splitting; but if you're not careful about what kind of question you're asking, you may well end up giving answers which are irrelevant, or ones which don't actually give any information, though they appear to.

Once you stop making difficult and highly specialised investigations of, for example, what is going on in someone's brain when they swear — investigations only undertaken by carefully trained people in laboratories — and other particular problems about the location of different functions in the brain, and ask, 'How on earth do we manage to organise our hugely complex experiences into concepts which enable us to understand and communicate them to one another?' the result is likely to be a more or less thinly disguised platitude, even a tautology. 'We do because we can' may well be what we are saying, but dressed up in fancy language. When Pinker follows Kant in claiming that we are born with a very fundamental set of categories — space, time, causality, substance — which enable us to make sense of the world, that may sound as if he, and Kant, had discovered something about the mind (or brain, if you're sufficiently muddled). But all anyone is entitled to say is that if we didn't have these concepts we would be at a loss in the world — to say that they are 'innate' is not to claim that we have discovered something about the mind which we didn't know before. To think that we have is to repeat, as so often, the old mistake that something is being explained when you say that opium puts people to sleep because it has a dormitive faculty. Pinker no doubt has done his laboratory work, and discovered many things about how brains function. But he needs to be careful not to claim more for the results of his enquiries than he is entitled to. And if he weren't so enchanted by linguistic quirks he might have more energy for finding out what philosophers do.