 With regard to the first issue, there is some evidence that Davidson is confusing two distinct questions: why mental concepts cannot stand in lawlike relation to physical concepts, and why mental concepts cannot be eliminated in favor of physical concepts in the explanation of human behavior. Given the general thesis about causally defined properties, we have an understanding of why mental concepts are anomic. But this leaves open the question whether we ought to continue to traffic in anomic concepts generally, and mental concepts in particular. Why not eliminate them in favor of the nomic physical concepts? Here, the rationality of mental concepts may be thought to provide an answer. If we wish to understand why an agent performed the action that she did, as opposed to having a full sufficient causal explanation of why her body moved as it did, we are interested in a selective explanation—that part of the total sufficient condition that satisfies the particular explanatory interests behind reasons-explanations (Davidson 1991, 163). Those interests highlight the normative nature of reason and action—their responsiveness to the principle of charity and ideal of rationality. Rationality, on this line of thinking, does not account for mental anomalism; but it does speak to the question of mental realism (see further  6.2).  (For further discussion of the anomic nature of causally defined concepts and its bearing on Anomalous Monism, see Yalowitz 1998a. For more on the relation between rational explanation and mental realism, see the supplement on  Explanatory Epiphenomenalism.  For discussion of issues closely related to the causal definition argument, see  6.3  and the supplement on  Related Issues  (Mental Anomalism and Semantic Externalism).