Desires and Explanatory Reasons

This paper has four aims and sections, the first two are positive or constructive and deal with the concept of 'desire', the latter two, discussing various concepts of 'explanatory practical reason', are negative or critical. (1) First a certain concept of 'desire' is explained, which lies broadly in a Humean tradition. (2) Then it will be shown that this concept is apt for the philosophy of action, or more specifically, that it is suitable as a central and fundamental concept in an empirical theory of action because it can be used in important psychological laws about the formation of decision and intention. (3) The third section shall show that the usual concept of an 'explanatory practical reason' is much less apt for this task because of the variety of things denoted with this concept. (4) The final section explains why fashionable concepts of 'explanatory practical reason', which are inspired by externalist theories of rationality, are much less useful because they have been designed without relation to any empirical theory of action.