Exclusion, Overdetermination, and the Nature of Causation

Abstract

A typical thesis of contemporary materialism holds that mental properties and events supervene on, without being reducible to, physical properties and events. Many philosophers have grown skeptical about the causal efficacy of irreducibly supervenient properties, however, and one of the main reasons is an assumption about causation which Jaegwon Kim calls the causal exclusion principle. I argue here that this principle runs afoul of cases of genuine causal overdetermina-tion. Many would argue that causal overdetermination is impossible anyway, but a careful analysis of these arguments shows them to be misguided. Finally, I examine the reasons given in support of the causal exclusion principle, and I conclude that it is plausible if, and probably only if, a certain view of the nature of causation turns out to he correct. Since that view of causation is unacceptable to nonreductivists on other grounds, however, it turns out that exclusion-based arguments essentially beg the question.