Should a Naturalist Be a Supervenient Physicalist?

I clarify a widely accepted form of contemporary naturalism and argue that supervenient physicalism should not be considered an option for those who embrace this version of naturalism. Among other things, my thesis implies that if there are insuperable difficulties for strict physicalism, then the move toward supervenience views of the mind/body problem amounts to an abandonment of this version of naturalism and not a minor adjustment of it. More precisely, my argument is this: strict physicalism excludes both substance and property or event dualism. But the supervenience thesis entails some form of property or event dualism. So strict physicalism excludes the supervenience thesis. Moreover, given the nature of a widely accepted contemporary understanding of naturalism, it is best construed along strict physicalist lines and naturalists of this persuasion should not be supervenient physicalists. To make my case, I offer a characterization of a ubiquitous version of contemporary naturalism followed by an analysis of the most plausible version of supervenient physicalism consistent with this form of naturalism. I then try to show why this version of supervenient physicalism should not be an option for a naturalist of a certain persuasion.