In the Hands of Zombies

A ZOMBIE IS quite simply a physical and functional duplicate of you or me, who differs from us only in that she does not possess consciousness or phenomenological experience. 1 In other words, we know what it is to feel pain, happiness, and anger; a zombie does not: she completely lacks such experience. Many philosophers have recently befriended zombies. That is to say, these philosophers believe in the metaphysical possibility of the existence of a zombie, zombie-possibility for short. Prima facie, zombie-possibility seems to refute materialism as a solution to the Mind-Body Problem. Materialism is the view that mental states are identical to physical states, i.e. any phenomenological experience is nothing but some physical state. 2 This view entails a so-called logical supervenience: mental states supervene on physical states. Assuming zombie-possibility, an argument against materialism might roughly go like this: by definition, a zombie is in exactly the same physical state as we are, but lacks our mental states. Hence, our mental states must be something " above and beyond " our physical states. Thus mental states do not supervene on physical states, contra materialism. In this paper I will argue that a materialist can deny zombie-possibility, and hence resist anti-materialist arguments based on this premise. In §2 I show where and how this allows a materialist to object to Saul Kripke's famous modal arguments. §3 considers David Chalmers's version of anti-materialism; again I explain where this argument fails. In §4 I discuss the issue of whether a materialist is in fact faced with burden of proof, something that the literature often seems to assume. I then present an explanation in §5 that is intended to satisfy Kripkean questions of apparent contingency in materialism. Finally, §6 contains a concluding summary and final remarks. Two points before I begin: first, I assume that the reader has a basic understanding of modal metaphysics. This includes notions of a prioricity, necessity, modality de re, and modality de dicto. Second, throughout §2-§5 I will most often just discuss the identity of pain and C-fiber stimulation as opposed to a general thesis of materialism. This is simply for ease of exposition; it is clear that there is no loss of generality in restricting ourselves to this single identity thesis. In this restricted form, a zombie is simply one who has C-fiber stimulation but no pain, and zombie-possibility is the metaphysical possibility of such a zombie.