Robert Kirk

By definition zombies would be physically and behaviourally just like us, but not conscious. This currently very influential idea is a threat to all forms of physicalism, and has led some philosophers to give up physicalism and become dualists. It has also beguiled many physicalists, who feel forced to defend increasingly convoluted explanations of why the conceivability of zombies is compatible with their impossibility. Robert Kirk argues that the zombie idea depends on an incoherent view of the nature of phenomenal consciousness. His book has two main aims. One is to demolish the zombie idea once and for all. There are plenty of objections to it in the literature, but they lack intuitive appeal. He offers a striking new argument which reveals fundamental confusions in the implied conception of consciousness. The book's other main contribution is to develop a fresh and original approach to the true nature of phenomenal consciousness. Kirk argues that a necessary condition is a 'basic package' of capacities. An important component of his argument is that the necessary cognitive capacities are not as sophisticated as is often assumed. By focusing on humbler creatures than ourselves he avoids some of the distracting complications of our sophisticated forms of cognition. The basic package does not seem to be sufficient for phenomenal consciousness. What is also needed is 'direct activity' - a special feature of the way the events which constitute incoming perceptual information affect the system. This is an integrated process, to be conceived of holistically, and contrasts sharply with what is often called the 'availability' or 'poisedness' of perceptual information. This original, penetrating, and readable book will be of interest to all who have a serious concern with the nature of consciousness: not only professional philosophers and students, but psychologists and neuroscientists.

Sydney Shoemaker thinks the ‘most revealing characterization of physicalism’ is in terms of realization . He offers a meticulously worked out account of physical realization and goes on to apply it to a range of major topics: mental causation, personal identity, emergence, three-dimensional versus four-dimensional accounts of temporal persistence, qualia. 1 He also discusses constitution by micro-entities, functional properties, causation by ‘second-order’ properties, ‘phony’ and ‘genuine’ properties, and whether mental properties strongly supervene on physical ones. Several parts of the book are devoted to criticizing Jaegwon Kim's views, especially in his Physicalism, or Something Near Enough .I shall concentrate on three main issues: whether, as Shoemaker claims, his official view of physical realization provides for a ‘constitutive link’ between the realizer and what it realizes; whether his account is a ‘revealing’ characterization of physicalism; and his discussions of transposed and ‘alien’ qualia. Let me remark that numerous potential objections are treated with sophistication and subtlety. At several places, this makes for difficult reading . It also means I shall usually be simplifying the views I attribute to him

If zombies were conceivable in the sense relevant to the ‘conceivability argument’ against physicalism, a certain epiphenomenalistic conception of consciousness—the ‘e-qualia story’—would also be conceivable. But the e-qualia story is not conceivable because it involves a contradiction. The non-physical ‘e-qualia’ supposedly involved could not perform cognitive processing, which would therefore have to be performed by physical processes; and these could not put anyone into ‘epistemic contact’ with e-qualia, contrary to the e-qualia story. Interactionism does not enable zombists to escape these conclusions

Suppose P is the conjunction of all truths statable in the austere vocabulary of an ideal physics. Then phsicalists are likely to accept that any truths not included in P are different ways of talking about the reality specified by P. This ‘redescription thesis’ can be made clearer by means of the ‘strict implication thesis’, according to which inconsistency or incoherence are involved in denying the implication from P to interesting truths not included in it, such as truths about phenomenal consciousness. Commitment to the strict implication thesis cannot be escaped by appeal to a posteriori necessary identities or entailments. A minimal physicalism formulated in terms of strict implication is preferable to one based on a priori entailment

How should we conceive of physicalism? Does it have to involve more than some kind of supervenience, or must it be reductionist or even eliminativist? Does it commit you to the psychophysical identity theory? Does it entail that all events are explicable in terms of physics? And what is to count as the physical—indeed, what is to count as physics? Jeffrey Poland offers well-argued answers to several of these questions, and a solidly constructed framework in terms of which we may reasonably aim to answer the rest. His book is impressively systematic. He acknowledges debts to Post and to Hellman and Thompson, among others, but his conception of what physicalism should be is distinctive. I find it compelling. Anyone with an interest in physicalism, for or against, should read the book.

I have argued that a strong kind of physicalism based on the strict implication thesis can consistently reject both eliminativism and reductionism (in any nontrivial sense). This piece defends that position against objections from Andrew Melnyk, who claims that either my formulation doesn't entail physicalism, or it must be interpreted in such a way that the mental is after all reducible to the physical. His alternatives depend on two interesting assumptions. I argue that both are mistaken, thereby, making this kind of nonreductive physicalism clearer and more clearly defensible