Abstract

A prominent objection to supervenience physicalism is that a definition of physicalism in terms of supervenience allows for physicalism to be compatible with nonphysicalist outlooks, such as certain forms of emergentism. I take as my starting point a recent defense of supervenience physicalism from this objection. According to this line of thought, the subvenient base for emergent properties cannot be said to be purely physical; rather, it is “polluted” with emergent features in virtue of necessarily giving rise to them. Thus, if emergentism is true, it is false that everything supervenes on physical properties. I argue that this gives way to a new challenge for supervenience physicalism. The challenge, roughly, is to distinguish the emergentist’s “polluted” base from a physical supervenience base; that is, to give conditions under which the subvenient base is not “polluted” by supervenient properties. The problem, I argue, is that it is hard to see how this can be done without collapsing supervenience physicalism into alternative approaches to physicalism. I thus argue that if the present defense of supervenience physicalism succeeds in defending the adequacy of a supervenience-based definition of physicalism, it does so by compromising its uniqueness