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Neurophilosophy: Toward a unified science of the mind-brain

1987, Neuroscience

contingent: and into problems of the content of mental states. These latter I feel they too easily dismiss: on pp. 216-19, Nagel's theory is sketched and the authorswho definitely want to say that there is something that it is like to feel pain etc.make the claim that this is not itself a piece of information and hence not a fact about the world, for which science needs to find room. They claim that a theory of sensation need make no room for 'what it's like' to feel that sensation, since such a theory can only deal with information, while experience and practical knowledge, which are gained byor inknowing what something is like are not pieces of information. But this agrees with Nagel's view that the subjective facts cannot be captured from the objective perspective.

zyxw zyxwv zyxw contingent: and into problems of the content of mental states. These latter I feel they too easily dismiss: on pp. 216-19, Nagel’s theory is sketched and the authors - who definitely want to say that there is something that it is like to feel pain etc. - make the claim that this is not itself a piece of information and hence not a fact about the world, for which science needs to find room. They claim that a theory of sensation need make no room for ‘what it’s like’ to feel that sensation, since such a theory can only deal with information, while experience and practical knowledge, which are gained by - o r in - knowing what something is like are not pieces of information. But this agrees with Nagel’s view that the subjective facts cannot be captured from the objective perspective. I at least would have liked to see more discussion of this problem of the content of consciousness. The authors rather implausibly deal with this by invoking what are essentially feed-back mechanisms: we have sensations, perceptions, beliefs, desires etc. at the primary level of consciousness but at the second level can report on our own inner states via internal connections. Thus knowing that I’m in pain is distinct from being in pain - and the clamorous character of pain sensations is explained by evolutionary advantage. Hence too there is no mystery about differences between first and third person reports of inner states. This seems to me a palliative rather than a serious response, although it can lead to deeper issues and the authors indicate that there is more to be said here. Despite these and other differences of opinion that I may have with the positions argued, study of them will certainly enable the reader to move on with profit to much contemporary work in the philosophy of mind, but without encouraging an unhealthy dogmatism either in the direction of the authors’ own view o r that of any other. While they develop and argue for a particular theory, they d o so quite self-consciously and with an unsparing clarity which makes it easy to see their faults as well as their virtues. The book is written for a wider and less sophisticated group of readers than is, for instance, Colin McGinn’s The Character of Mind. I t could usefully serve as a basis for discussion of a wide range of issues, including those Aristotelian theories, related to those advanced by K. V. Wilkes and David Charles, which underlie some of their treatment, but which are not spelt out in enough depth to make any assessment of them possible. zyx UNIVERSITY OF GLASGOW J A N E T SISSON Neurophilosophy: Toward a Unified Science of the Mind-Brain By PATRICIA C H U R C H L A N D M.I.T. Press (Bradford Books), 1986. xi 546 pp. 527.50 + This is an impressive book. I t summarises a great deal of modern work in neuroscience, gives a forthright statement of eliminative materialism and suggests a theoretical approach to certain problems in human information processing which is firmly tied to our understanding of 233 zyx zy neurophysiology. However, from the outset it is clear that a ‘hip-shooting’ attitude is to be taken to certain conceptual matters: “. . . the brain investigates the brain, cmburdened no doubt with a pack of misconceptions” (p. 1). Now, what is sure is that the brain does not misconceive, it reliably processes input that it receives and its output reflects that input and the processing that has been done on it. The person whose brain it is might, however, misconceive, because for her it makes sense to think of herself as going right o r wrong in the way she thinks about things or deals with information in her possession. A continuing problem throughout the book is that crucial steps in some arguments are not handled with perspicuous attention to the conceptual issues involved. We are told that “the evolutionary step that interposes neurons between sensory neurons and motor neurons . . . permits the building-in of a basic world representation” (p. 77) but not what is meant by this claim. Does the author mean flexibility of response based in a modulation of simple S-R links or does she mean something with more epistemological weight? A similarly elusive remark leaves us wondering what revelations might be forthcoming which link brain processes and the essence of our thought: “research on split-brain patients . . . social psychology and the philosophical theory underwriting revisionary materialism are converging” (p. 192). ‘Converging on what?’, we might ask. I n the section on neuropsychology there is a wealth of material, equally fertile as brain bisection data, upon which philosophers can work to elucidate the nature of mind. What is disappointing is that throughout Churchland’s discussion of epistemology and the philosophy of mind she focusses on the rather lame strands represented by introspection and the ‘theory’ theory of mental ascriptions. There is no explicit recognition that Wittgenstein o r even Davidson might evade her major criticisms. Thus the philosophy is untrammelled and forthright but disappointing in a revealing way. Churchland rightly chastises the overready assumption that rationality as a distinct connecting principle may defeat reduction and refuses to be swayed from the view that rational constraints may be explicable in causal terms. However, her discussion does not address nor apparently recognise the fact that ‘rationality’ in its broadest reading, captures normative features of thought that may elude an account in terms of internal mental states. So one is left with the feeling that, having fared well in the skirmishes, Churchland is unwilling to try the issue in a pitched philosophical battle with the most powerful anti-reductive views where the opponent has a clear conception of the pervasive role of reason, rules and norniativity in human thought. It may be that to explain these properties of thought is to go beyond (or transcend) the categories available to reductive neuroscience even though there must be cognitive processes of certain types to enable us to think. The same problem resurfaces in the discussion of meaning. “What an expression nieans is a function of its inferential/computational role in the person’s internal system of representations, his cognitive economy” (p. 344). Such a view gives LIS no clear account of the a priori o r 234 constitutive intersubjectivity of meaning which allows the same content to be grasped by different thinkers who participate in a milieu of dialogue where their thought develops. Any adequate account of meaning must explain how and why this is so. The elements of that explanation are unlikely to be confined to the processes going on inside the head of a given thinker (and therefore inaccessible to others who share and appreciate the ways in which he represents the world). It is inevitable that neglect of this requirement leads to the conclusion that semantic features are “irrelevant content specifications” in the explanation of behaviour (p. 383). The section on “sentence-crunching’’ as a model of thought is telling and well-argued, drawing on both philosophical and empirical support (pp. 376-400). It culminates in an answer to the charge of self-refutation often laid at the door of the eliminative materialist (pp. 397ff.). The problem is posed in terms of beliefs but the anti-eliminativist can make a strong point in terms of the articulation and evaluation of all theory and the detection of ill-grounded reasoning. These are essential in any representation of the world, they are related to the normative problem raised earlier and they imply that it will not do to construe knowledge and valid argument on the basis of what complex systems are disposed to d o by their inputs and internal states. It is not “unique availability” of folk theory that tells here, rather a conceptual foundation upon which to assess the meaning and validity of “Neuropsychological state[s] defined within the mature new theory” (p. 397). The last chapter of the book is exciting and provocative. It discusses tensor-network theory, parallel distributed processing and a theory of attention. As to the first, it is instructive that the examples offered are drawn from areas of neurological information processing where an automatic transition between input and output allows smooth and unreflective adaptation of movement to sensory changes. This is followed by the claim that “higher functions are surely not discontinuous with lower functions” (p. 451). What goes unchallenged is the idea that reflective, judgement-involving, non input-driven, thought is of the same conceptual stuff as sensorimotor co-ordination. Prima facie it does not seem to be and nothing is offered to advance the suggestion that it is. I n the light of conceptual defects elsewhere in the book one must suspect that the problems have not been fully appreciated. When we move to PDP models, we indeed have an intriguing basis on which to understand how neuronal networks might subserve conceptual thought but only the merest hint of what might shape and influence the set of concepts or “rules of the understanding” (Kant) that structure our thought. Here Churchland might usefully have reconsidered her suggestive remarks about conspecifics (p. 224). Discussion of the attentional “searchlight” comprises a few preparatory and gestural remarks. The functional shape that the system takes on and the conceptual explanation of why attention favours the items that it does both remain a mystery. I find the book both stimulating and informative but must take issue zyxwvut zy 235 zyx zy zyxwvu zyxwvuts zyxwvu with the impoverished philosophical conceptions of mind and mental ascriptions which are imputed to the non-eliminativists. MAGDALEN COLLEGE, OXFOKD GRAN'r G I L L E T T Kant, Respect and Injustice: The Limits of Liberal Moral Theocv By VICTOR J. SEIDLER Routledge & Kegan Paul, 1986. xii 244 pp. €19.95 + T h e thesis of this book is that it is impossible for the Kantian conception of respect for persons either to do justice to the individual self or to accommodate the genuine equality between persons which it seems to promise. The Kantian 'end-in-himself' is pure reason, abstracted from the wants and feelings which constitute individuality. Kant tells us that feelings are externally conditioned and have no ultimate worth or dignity; the true self is the reasoning and choosing self, belonging to the noumenal world and stripped of all individuating qualities. Seidler argues that belief in this doctrine entails a fragmented sense of the self, which makes people stress achievements while ignoring feelings and lose themselves through endeavouring to repudiate those elements of their personality which stem from class, race o r sex. He suggests that the individual personality is in part something which its owner learns about, rather than chooses; trying to ignore feelings makes a person less autonomous rather than more, as Freud saw. An important aspect of Kant's doctrine of respect for persons as ends is the democratic idea that every human being possesses dignity equally in virtue of his capacity for morality and can be valued simply as a human being, in abstraction from his particular characteristics and position in society. Seidler argues that this claim of equality is a delusion, because a person who is fundamentally dependent on others does not have the autonomy on which dignity depends: for example, he may see his life and its possibilities in terms not of his own projects but of the image of himself given to him by his superiors. Relationships of power and dependence, whether between rich benefactor and poor beneficiary, employer and employee in capitalist society o r men and women in their traditional roles, institutionalise this destruction of dignity; it is not possible for an individual to restore it simply by behaving well to his inferiors. Seidler holds that Kant sometimes seems to be aware that the rich can undermine the dignity of the poor by their beneficence, but he never suggests that the institutions themselves should be changed, and even thinks (according to Seidler) that those in a subservient position must be there by choice. This enables him to preserve the doctrine that everyone is equally capable of morality. Seidler quotes passages in which Kant advocates that those who are dependent on others should be denied civic rights while claiming that this in no way impairs their equal status in the noumenal sphere as rational wills possessing dignity. Modern liberals in the Kantian tradition, such as Rawls and Dworkin, have not been content to secure equality 236