Abstract
This paper explores a less well-known cousin of the Exclusion Problem for non-reductive physicalism (NRP): what I'll call the Extrinsicality Problem. Non-reductive physicalists hold that mental properties are generally multiply realised by physical properties. The Exclusion Problem is that if the physical properties are causally sufficient for a given effect, there is no causal work left for the mental properties to do; hence NRP entails the causal inefficacy of the mental. Various promising counterfactual-based solutions are available to the Exclusion Problem; however, a deeper problem remains. Mental properties are thought to be multiply realised because they are functional properties: properties individuated by their typical causes and effects. But functional properties are extrinsic, and extrinsic properties are ill-suited for having causal status. This is the Extrinsicality Problem. I show how various proposed solutions to the Exclusion Problem are subject to the Extrinsicality Problem, but argue that the natural conclusion - epiphenomenalism with respect to the mental - is not as unfortunate as it is commonly taken to be.