 This point is important when one considers the wider framework to which the interaction principle contributes. Since Davidson is attempting to derive monism from it and other principles that are themselves neutral about the metaphysics of mind, he cannot assume that action is (identical with) behavior on pain of circularity. Once monism has been established, Davidson will be in a position to deploy the ‘because’ point in order to argue for the claim that mental events are causally efficacious with respect to physical events. How this relates to the wave of epiphenomenalist criticism about Anomalous Monism will be explored in detail below  (6,  and see the supplement on  Mental Properties and Causal Relevance).  To summarize, the interaction principle is an unargued assumption in the Davidsonian framework, one that does not assume monism, and the ‘because’ argument, while important for ruling out non-causal theories of action, does not itself establish the interaction principle.