Abstract

If we assume that a conceptual connection does hold between reasons and action, the arguments for both theses are strikingly simple. In defense of the first thesis, all that need be added is Hume's Principle: between cause and effect only a (logically) contingent relation holds. For given Hume's Principle, and the conceptual connection (which after all is not a contingent one), it follows that no causal connection holds. In defense of the second thesis, all that need be added is one assumption and one observation. The assumption is that the covering-law model of explanation is adequate to the natural sciences; the observation is that if a conceptual connection does hold, then covering-laws are not required to explain a person's action given the presence of the relevant beliefs and desires (because the presence of the latter entail the performance of the former). Together the assumption and the observation undermine the view that one model of explanation will fit both natural science and human psychology