Imagining subjective absence: Marcus on zombies

The claim that zombies are conceivable is a premise of one of the most important anti-physicalist arguments. Eric Marcus (2004) challenges that premise in two novel ways. He observes that conceiving of zombies would require imagining total subjective absence. And this, he argues, we cannot do. However, his argument turns on the assumption that absence is imaginable only against a background of presence and, I argue, that assumption is dubious. Second, he proposes that the premise’s intuitive plausibility derives from a scope confusion. However, I argue, on reflection that proposal is untenable. Many philosophers accept the conceivability of zombies: creatures that lack consciousness but are physically and functionally identical to conscious human beings. Many also believe that the conceivability of zombies supports their metaphysical possibility. And most agree that if zombies are metaphysically possible, then physicalism is false. So, the claim that zombies are conceivable may have considerable significance. Eric Marcus (2004) challenges this conceivability claim in two novel ways. First, he observes that conceiving of zombies (in the sense relevant to the anti-physicalist conceivability argument) requires imagining total subjective absence. And this, he argues, we cannot do. Second, he suggests that the plausibility of the claim that zombies are conceivable derives from a scope confusion. Marcus’ overall strategy has the right form. His proposals illustrate the kinds of substantive moves that would be required to answer the challenge to physicalism based on the conceivability of zombies. But he does not succeed in this endeavour. His argument against the 1 Throughout the paper, I go back and forth between the claim that zombies are conceivable and the claim that a zombie world is conceivable, where a zombie world is a minimal physical and functional duplicate of the actual world but without consciousness. The differences between these claims do not matter much here. 2 This virtue is lacking in other recent discussions of the argument. See, for example, Beaton 2005, p. 21.