Abstract

What does it take to solve the exclusion problem? An ingenious strategy is Stephen Yablo’s idea that causes must be commensurate with their effects. Commensuration is a relation between events. Roughly, events are commensurate with one another when one contains all that is required for the occurrence of the other, and as little as possible that is not required. According to Yablo, one event is a cause of another only if they are commensurate. I raise three reasons to doubt that this account solves the exclusion problem successfully. First, it leaves a mystery about what determines a particular’s causal capacities. Second, because there are two ways of construing coincidence between particulars, a dilemma arises: either the solution to the exclusion problem is threatened, or the account of coincidence loses an attractive feature concerning ontological economy. Third, even if we assume the commensuration constraint, a plausible principle about overdetermination seems to regenerate the exclusion problem