Mind: A Brief Introduction (John R. Searle) / quote 99 of 138
Three arguments against dualism
The refutation of dualism is harder. Let us define dualism as the view that there are two distinct metaphysical ontological realms in the universe, one mental the other physical. This is harder to refute, because whereas materialism postulated the nonexistence of something we know to exist, this view postulates the existence of something, and to refute it formally you would have to prove a universal negative. Rather than give a formal “refutation,” I will give what I take to be conclusive arguments against dualism. 1. No one has ever succeeded in giving an intelligible account of the relationships between these two realms. 2. The postulation is unnecessary. It is possible to account for all of the first-person facts and all the third-person facts without the postulation of separate realms. 3. The postulation creates intolerable difficulties. It becomes impossible on this view to explain how mental states and events can cause physical states and events. In short, it is impossible to avoid epiphenomenalism. Notice that these arguments still leave dualism as a logical possibility. It is a logical possibility, though I think extremely unlikely, that when our bodies are destroyed, our souls will go marching on. I have not tried to show that this is an impossibility (indeed, I wish it were true), but rather that it is inconsistent with just about everything else we know about how the universe works and therefore it is irrational to believe in it.