Abstract:  The standard argument for the causal theory of action is “Davidson's Challenge”: explain the connection between reasons and actions without appealing to the idea that reasons cause actions. I argue that this is an argument to the best contrastive explanation. After examining the nature of contrastive explanation in detail, I show that the causalist does not yet have the best explanation. The best explanation would appeal further to the motivational strength of reasons. Finally, I show how this undermines the argument for causalism, since noncausalists, too, can meet Davidson's Challenge by appealing to motivational strength to explain the cases at issue.