In two of his more recent papers, Donald davidson has argued for the "a priori" truth of what he calls "the principle of the anomalism of the mental." my concern in this paper is with examining that principle and davidson's defense of it. After clarifying the principle, I discuss three considerations which davidson gives in its defense and argue that they are not persuasive. Then I argue that although the principle of the anomalism of the mental cannot be known "a (...) priori" to be true, There are some arguments and some neurophysiological evidence which make it reasonable to believe that the principle is, Indeed, True. (shrink)