I’m continuing my slow progress through Etienne Gilson’s The Spirit of Mediaeval Philosophy (slow because I’m mostly reading it while eating lunch at work on those days when I eat by myself) and I’m rather enjoying it. I’m finding it much more accessible than Gilson’s The Christian Philosophy of St. Thomas Aquinas, which I attempted a couple of years ago and didn’t get too far with. (To be fair, I think I’d have an easier time with it now than I did then.)

As I commented last week, Gilson is concerned to delineate in exactly how there can be such a thing as a “Christian Philosophy” distinct from theology; and his argument is that there are truths, accessible by philosophical methods, that occurred to Christian philosophers but not to the earlier Greeks purely because they were suggested by Judeo-Christian revelation. The neat thing is that in order to support this claim, Gilson needs to lay out very carefully how scholastic philosophy, and particularly the philosophy of St. Thomas Aquinas, differs from its Greek antecedents.

The result, so far, is fascinating. The books I’ve read previously have generally talked about Thomas and Aristotle at the same time in much the same way. While recognizing that the former received and extended the latter’s thought, they have generally discussed them together, as a unit. And yet there are significant differences.

As an example (and the subject of Gilson’s fourth chapter), Aristotle has the notion of the unmoved mover, the entity ultimately responsible for all motion in the universe. Remember that for Aristotle, “motion” includes all change, including things coming to be and ceasing to be. But for Aristotle, this unmoved mover is simply stirring the pot. The universe has always existed, and new things that come to be are made out of previous things that existed. Most things are in flux, and it’s the unmoved mover that makes that happen. There is no notion of creation in the Christian sense in Aristotle. The unmoved mover is in some sense pure Thought; but it is not (as Thomas would say) Being itself.

In Thomas’ view, and using essentially the same arguments as Aristotle, the unmoved mover becomes the cause, not only of motion, but of being. As Being itself (“I am who am,” as the burning bush tells Moses), the unmoved mover is responsible not only for the changes in things but for their very existence, for the existence of all things other than itself. This is consistent with Aristotle’s understanding; but it goes further and deeper.

In short, Gilson is casting light on both Thomas and Aristotle, and helping me to see both in new ways. I’m curious to see what’s coming next.