 Davidson repeats these sorts of claims about the anomic nature of causally defined properties in a number of places in later writings, but at no point does he clearly bring them into contact with his early remarks concerning the constitutive role of rationality in psychological ascription. And he never provides argument in support of this general thesis concerning causality. It is natural to wonder why, given this general thesis about causally defined concepts, rationality should be thought to underwrite mental anomalism. And it becomes imperative to know why that general thesis is plausible (for discussion, see Yalowitz 1998a).