Abstract

The classic question about mind-body interaction is now construed as a question about the causal relevance of mental properties. Beyond a materialist account of how reasons can be causes simpliciter, what we seek is a demonstration of how reasons can be causes in virtue of their contentful and rational features. This dissertation attempts to furnish such a demonstration. ;The demonstration falls into two parts: an account of how intentional properties are causally relevant in a metaphysically possible world and a separate account of how they can be relevant in a world where materialism is true. The metaphysical possibility of mental relevance, it is argued, requires psychological laws. These are confirmable and counterfactual-supporting generalizations formulated in terms of beliefs, desires and actions. Mental relevance in a world like ours, on the other hand, requires, in addition to psychological laws, relations of psychophysical determination. These are supervenience relations that hold with metaphysical necessity. Laws and determination, then, are what secure the relevance of mental properties. ;The existence of these relations, however, requires defense from Donald Davidson's famous argument for anomalism. The anomalism thesis has as its target the possibility of both types of relations, and it is primarily motivated by the worry that were intentional properties to appear in relations of either type, then that which is constitutive of intentional properties, their normative character, would face the threat of elimination. ;It is argued that this worry is groundless on both fronts. To defend the existence of psychological laws, an argument is presented for the claim that thought still retains its essential normative character within the context of interesting psychological laws. For the reality of psychophysical determination, a separate argument is presented for the claim that radical interpretation, a theory that by its very nature guarantees the normative character thought, must endorse determination on pain of incoherence. Both arguments attest to the compatibility between the norms that are essential to thought and the laws that are necessary for its relevance.