  LePore and Loewer discuss a version of this worry. Condition (3), an objector might say, is too crude to test for causal relevance, for the counterfactual holds only because removing F from a also removes some other property F* of a, and it’s the absence of F* that’s responsible for b’s not being G. A better counterfactual test evaluates the effect’s status given that a is not F and all of a’s other properties—or at least all that are potential causal rivals to F—are held fixed. If b is not G in that case, only then can we credit F with causal relevance. But mental properties fail this more refined test. Consider again Gus’s decision to turn on the light, and remove its mental property, this time holding fixed its physical properties. It seems clear that he would still flip the switch. After all, the physical properties of the cause figure in an exceptionless law according to Davidson. It looks as if the physical properties of your decision “screen off” the mental property, making the latter irrelevant.