In a previous post about philosophy and the existence of God, I made a couple points.
First, about the classical understanding of philosophy as a way of life and even, as Artur Rosman puts it, a set of spiritual exercises.
Second, a useful heuristic being to look at philosophers who open up a new era as “the last of [what came before]” as much as “the first [X].”
Thus, describing Descartes as the last Ancient philosopher, I wrote:
Christianity unwittingly dealt a mortal blow to this understanding of philosophy, by treating the Ancients as a reservoir of concepts they could repurpose to do theology, and in the practical realm by privileging the Christian way over the philosphic way, but the coup de grâce was administered by the Moderns and their rationalistic project.
Just like there are many “Last of the Romans”, I think you could also justifiably call Aquinas “the last Ancient philosopher”.
I think the key to understanding Aquinas is that, first of all, he was a mystic–one only has to read his hymns–, and second of all, he was a teacher, a pedagogue and even a mystagogue. He was, after all, a member of the Order of Preachers! (And how he strove to join that then-not-so-venerable Order.)
We tend to think of him as sitting in his study immersed in Deep Thought and writing down Deep Thoughts, but the reality was far different. He was a university professor, and he was also involved in Church politics of his day, both general ecclesiastical politics and within the politics of his Order.
The “Summa” in “Summa Theologica” does not mean “masterwork” or “systematic theology”, it means “summary,” and the Summa was intended as a (introductory!) textbook for seminary students.
Aquinas did not intend to build a complete, self-sustaining rationalistico-theological “system” as so many maintain (most decrying it, a few lauding it), but rather he saw himself as only a faithful expositor of the Scriptural and Patristic deposit of the faith; and like the Church Fathers before him he used in part Greek philosophy to do so.
But precisely because of his reverence for, and knowledge of, Ancient philosophy, he knew that it was at least as much about the philosophic way of life as about rational concepts, and he sought not to destroy this way of life but (again, like the Fathers) to subsume it within the greater whole of the Christian Way.
Nowhere is this clearer than in the much-maligned Quinque Viae. These are not “proofs”, they are ways. (Or rather, not only proofs–they are also proofs, and they work as proofs. But they are not merely proofs.) Thomas is much maligned for putting philosophical discussion de Deo uno before the theological discussion de Deo Trine, but for him, they are not just rational arguments, they are also–very much in the spirit of the Neoplatonic-inspired Pseudo-Dionysius, whom Aquinas cites as much as Aristotle–ways for the mind to rise towards the contemplation of God.
Back in his day no doubt as well as in ours, the great danger, the perennial idolatry, is the anthropomorphization of God, the natural instinct that all humans have to think of the divine agent as some sort of chap sitting up there. Aquinas’ de Deo uno—de Deo Trine procession, in a way, mirrors that of the Old and the New Testament: the Old Testament is all about divine transcendence, because it is only when this has been firmly established that the mystery of the Incarnation can be properly contemplated. Zeus taking human form is no big deal–he did it many times. It is only when we understand, in whatever way we can, that there is no Zeus-like God, that God, in any coherent way of using that word, can only be Uncaused Cause, Pure Act, Subsistent Being, etc. that we can begin to grasp the Christian mystery and not devolve intopaganism.
If you are writing an introductory theology textbook, then, it would be vital for you to teach those future teachers of the faith about this crucial distinction, this necessary background. And it would be crucial to teach them, not, or not just, rational propositions, but also ways for the mind to rise towards the contemplation of the divine mystery. Once one has not just studied, but contemplated the Quinque Viae, it becomes nearly impossible to commit this neopagan idolatry to which I have referred; then are you ready for contemplation of the divine mysteries properly unique to the Christian Revelation. A way of thinking about God and a way of contemplating God has been firmly engrained, which both safeguards one from a great many highly venomous errors and opens up extremely profound pathways into the divine mystery.
There has been a contemporary reaction, to say that properly Christian theology must start with Deo Trine, with the God of salvation history as he reveals himself to the experience of the Christian. Not the God of the philosophers, the God of Abraham, Isaac and Jacob. But while there’s certainly nothing wrong with that approach, there is certainly always the risk of falling into a fideistic, or neo-pagan, or experiential-existentialist understanding of God that would ultimately destroy his transcendence, and therefore his plausibility and his believability, and frankly this is a trap in which countless have fallen, especially outside the visible boundaries of the Church.
Once we understand, as Aquinas certainly did, the Christian life as involved in contemplation of the Truth and a participation in that Truth at certain levels, we find ourselves completely detached from those many false dichotomies.