Abstract
A popular solution to the causal exclusion problem in the non-reductive physicalist camp is the trope identity solution. But this solution is haunted by the “quausation problem” which charges that the trope only confers causal powers qua physical, not qua mental. Although proponents of the trope solution have responded to the problem by denying the existence of properties of tropes, I do not find their reply satisfactory. Rather, I believe they have missed the core presupposition behind the quausation problem. I will argue that the presupposition is the generalist notion of causation. Then, for the trope theorists to solve the quausation problem, they need to abandon the generalist notion and adopt the singularist notion of causation. However, making that move will lead them to a new quausation problem, rendering irreducible mental types causally irrelevant and mental causal explanations reducible. Either adopting a generalist notion or a singularist notion of causation, a quausation problem awaits the trope solution. Given this dilemma, my conclusion is that the trope identity solution cannot solve the exclusion problem in a non-reductive way. Moreover, the dilemma can be generalized, showing that token physicalism is a shaky position.