P. M. S. Hacker

Philosophical Foundations of Neuroscience


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brain, just as the maps of an atlas do for the reader of them. The biologist J. Z. Young writes of the brain having a language of a pictographic kind: ‘What goes on in the brain must provide a faithful representation of events outside it, and the arrangements of the cells in it provide a detailed model of the world. It communicates meanings by topographical analogies.’35 But is there a danger in the metaphorical use of such terms as ‘language’, ‘grammar’, and ‘map’ to describe the properties of the brain? … I cannot believe that any neurophysiologist believes that there is a ghostly cartographer browsing through the cerebral atlas. Nor do I think that the employment of common language words (such as map, representation, code, information and even language) is a conceptual blunder of the kind [imagined]. Such metaphorical imagery is a mixture of empirical description, poetic license and inadequate vocabulary.36

      Blakemore’s confusion

      Just how easy it is for confusion to ensue from what is alleged to be harmless metaphor is evident in the paragraph of Blakemore quoted above. For while it may be harmless to talk of ‘maps’ – that is, of mappings of features of the perceptual field on to topographically related groups of cells that are systematically responsive to such features – it is anything but harmless to talk of such ‘maps’ as playing ‘an essential part in the representation and interpretation of the world by the brain, just as the maps of an atlas do for the reader of them’ (our italics). In the first place, it is not clear what sense is to be given to the term ‘interpretation’ in this context. For it is by no means evident what could be meant by the claim that the topographical relations between groups of cells that are systematically related to features of the perceptual field play an essential role in the brain’ s interpreting something. To interpret, literally speaking, is to explain the meaning of something, or to take something that is ambiguous to have one meaning rather than another. But it makes no sense to suppose that the brain explains anything, or that it apprehends something as meaning one thing rather than another. If we look to J. Z. Young to find out what he had in mind, what we find is the claim that it is on the basis of such maps that the brain ‘constructs hypotheses and programs’ – and this only gets us deeper into the morass.

      Reply to fourth objection (Searle)

      Searle suggested that if ascribing psychological attributes to the brain really were a mereological error, then it would vanish if one ascribed them ‘to the rest of the system’ to which the brain belongs. The ‘rest of the system’, he held, is the body that a human being has. He observed that we do not ascribe psychological attributes to our body. With the striking exception of verbs of sensation (e.g. ‘My body aches//itches//hurts//all over’, as well as ‘You have hurt my foot’) this is correct. We do not say ‘My body perceives, thinks and knows’, nor do we say ‘My body has a pain in its foot’, let alone ‘My body has a pain in my foot’ or ‘You have given my foot a pain’. But the ‘system’ to which the human brain can be said to belong is the human being. The human brain is part of a human being, just as the canine brain is part of a dog. My brain, the brain I have, is as much a part of me – of the living human being that I am – as my legs and arms are parts of me.

      Human beings are (actually or potentially) persons, that is, they are intelligent, language-using animals that are self-conscious, possess knowledge of good and evil, are free and responsible for their deeds and have rights and duties. To be a person is, roughly speaking, to possess such abilities as qualify one for the status of a moral agent. It is striking that we would probably not say that the brain is part of the person, but rather that it is a part of the human being who is the person or that it is part of the person’ s body. To have a brain, one might say, is a somatic feature of a human being. Interestingly, we would not hesitate to say that Jack’ s brain is part of Jack, part of this human being, just as his arms and legs are parts of Jack. Why this hesitation or reluctance to aver that the brain is a part of a person? Perhaps because ‘person’ is, as Locke stressed, a ‘forensic term’, but not a substance-name like ‘cat’, ‘dog’ and ‘human being’. So, if we use the term ‘person’ in such contexts as this, we indicate thereby that we are concerned primarily with human beings qua possessors of those characteristics that render them persons, in relative disregard of corporeal characteristics. Perhaps this analogy will help: Paris is a part of France, France belongs to the European Union, but Paris does not. That does not prevent Paris from being a part of France. So too, Jack’ s being a person does not prevent his brain being a part of him.

      The mereological fallacy of illicitly attributing properties of wholes to their constituent parts has nothing to do with the distinction (or distinctions) between mechanical and non-mechanical processes. It is the bracket clock as a whole that keeps time, not its fusée, although the process of keeping time is