Aquinas’ Hylemorphic Dualism

Feser writes in response to Bill Vallicella on hylemorphic dualism:

That, I submit, is precisely the position Aquinas finds himself in.  As an Aristotelian, he is convinced that the human soul is the form of the living human body.  It is therefore responsible for all the various human capacities — nutrition, reproduction, growth, sensation, appetite, locomotion, intellect, and volition — in just the way the souls of plants and non-human animals are responsible for their capacities.  But Aquinas is also convinced that our purely intellectual capacities cannot have a corporeal organ.  The reason is that he endorses philosophical arguments for the immateriality of the intellect of the sort that go back to Plato and Aristotle.  That much gives him grounds for concluding that the soul carries out immaterial operations alongside its corporeal ones.  Add to this the (independently motivated) Scholastic thesis that agere sequitur esse — that “action follows being,” so that the way a thing acts reflects the manner in which it exists — and we have grounds for concluding that, though the soul is the form of the body, it must in some way have a kind of subsistent immaterial existence.  The view might seem odd, but it is hardly unmotivated or ad hoc.  On the contrary, it is a natural way of trying to reconcile two theses that Bill himself would acknowledge to have serious philosophical arguments in their favor.

I appreciated this post, as it explains how Aquinas is truly a dualist. It seems to me that  some Christians have tried to present Aquinas as an alternative to mind-body dualism, no doubt under cultural pressure to try to support a “Christian materialism” (like, e.g., the philosophy of Inwagen). It is helpful to have Aquinas’ dualistic bona fides presented more directly; it makes it obvious that hylemorphism is not an alternative to dualism.