 Mental Causation. Another debate that arises out of externalism concerns the legitimacy of wide contents in causal explanations. Most philosophers agree with Davidson (1980) that beliefs and desires play an important role in the causal explanation of actions. However, it is not clear how this can be reconciled with externalism. The problem comes up because it has been suggested that causal explanations of behavior should appeal only to the intrinsic properties of our bodies, properties that describe what is happening here and now within us (Stich 1983). But externalism says that mental contents are determined by causal, social or historical factors, factors which extend spatially and temporally beyond the body. This seems to imply that wide mental contents cannot be causally relevant because of their relational nature.