Causal Relevance and Thought Content

Kirk Ludwig

Abstract

This paper begins with the assumption that our thoughts are causally relevant to the movements of our bodies and the sorts of things to which these in turn are causally relevant in order to investigate the consequences for analyses of thought content. I argue for three necessary conditions on causal relevance: (a) a nomic sufficiency condition, (b) a logical independence condition, and (c) a screening-off condition. I apply these conditions to relational and functional theories of thought content, arguing that these theories cannot accommodate the causal relevance of content properties to our behavior. I argue further that, on two plausible assumptions, one about the dependence of the mental on the physical, and the other about the availability in principle of causal explanations of our movements in terms of our non-relational physical properties, content properties can be causally relevant only if they are nomically type-correlated, relative to certain circumstances, with non-relational physical properties of our bodies. Finally, I respond to a number of objections that might be made to my argument.