The causal contribution of the mental event is easy to demonstrate because the causal powers involved in the mental property's instantiation are identical to those involved in the physical property's instantiation. An argument made popular by Jaegwon Kim, shows that those who adopt a nonreductive form of physicalism have trouble making sense of the causal relevance of mental properties. This chapter presents that Kim's argument make use of a particular way of thinking about causation, is neither misguided, nor idiosyncratic. It argues that actually all physicalists should be optimistic about finding a productive account of causation. Kim is presupposing a productive or generative conception of causation, what he calls a 'thick' notion of causation. The primary argument for physicalism itself relies upon this production notion of causation. Finally, Kim's argument provides compelling reasons to adopt type physicalism over its currently more popular, nonreductive competitor.