A Defense of Nonreductive Mental Causation

Mental causation is a problem and not just a problem for the nonphysicalist. One of the many lessons learned from Jaegwon Kim’s writings in the philosophy of mind is that mental causation is a problem for the nonreductive physicalist as well. A central component of the common sense picture we have of ourselves as persons is that our beliefs and desires causally explain our actions. But the completeness of the “brain sciences” threatens this picture. If all of our actions are causally explained by neurophysiological events occurring in our brains, what causal role is left for our reasons and motives? It would seem that these brain events do all the causal work there is to do, thus robbing the mental of its efficacy altogether or else making it a merely superfluous or redundant causal factor. This essay presents a systematic treatment of this exclusion dilemma from the perspective of a nonreductive physicalist. I argue that both horns of this dilemma can be avoided if we ground mental causation in counterfactual dependence between distinct events and understand the mind-body relation as event realization. Although in the final analysis our actions are overdetermined by their mental and neurophysiological antecedents, this overdetermination is entirely unproblematic.