Aquinas’ Summa ranges from printings of 10 to 23 volumes (Black Friars comes to mind) and is not necessarily thrilling reading at points. I would not suggest it to anyone without a deep knowledge of Aristotle, the Middle Ages and deductive reasoning (along with the Scholastic disputation method and two years of spare time). Aquinas’ reasoning is deductive, not inductive and therefore your statement “I heard that he was big into deductive reasoning (stuff that is air tight)” is not necessarily accurate as it is not “airtight” in a Cartesian sense.
Kreeft’s collection is mediocre at best. The best collection of sections of the Summas is without a doubt from the former head of the Pontifical Institute of Medieval Studies Anton Pegis which is still in print.
Also, there are specialize collections of Aquinas’ writings such as his “Treaty on Law” or “An Introduction to the Metaphysics of St. Thomas Aquinas” both published by Gateway.
Walter Farrell’s Companion to the Summa is an excellent four volume set though I think it is out of print and getting harder and harder to find. Plus, without the Summa itself it is useless.
For Aquinas’ personal history (his life) I would recommend Josef Pieper’s Introduction to Thomas Aquinas or Frederick Copleston’s Aquinas. Etienne Gilson’s “Thomism” (published in English as The Philosophy of St Thomas Aquinas") is excellent but underwent a number of revisions.
For his metaphysics I would recommend Norris Clarke’s The One and the Many or Clarke’s collection of essays (both from Notre Dame press). Also, Jacques Maritain’s “Preface to Metaphysics” is excellent but deep.
For Aquinas’ epistemology consult the Degrees of Knowledge, Existence and the Existent or Bergsonian Philosophy and Thomism all by Maritain again or “The Christian Philosophy of St Thomas Aquinas” by Gilson (not to be confused with “The Philosophy of Thomas Aquinas” by Gilson). Pieper also has a book on Aquina’s epistemology called “The Silence of Aquinas” but I don’t have this one so I don’t know how good it is.
Gilson and Pieper both however admit that Chestertons only book on Aquinas “St. Thomas Aquinas: The Dumb Ox” is the best book ever written on Aquinas. I read this book four times while studying in Europe and I still think that Gilson and Pieper are correct in a sense. It might be the best but it isn’t the deepest. It is a good introduction to the spirit of Aquinas’ philosophy (speaking of which, Gilson’s Spirit of Medieval Philosophy is an excellent collection of lectures about how Thomism is Christian Philosophy par-excellence) but shallow on facts about his life and his philosophy/theology.
Pieper’s Introduction is probably the best introduction to the historical setting of Aquinas and his writings. I recommend Copleston highly also as Cospleston’s Aquinas gives much background information along with Aquinas’ ethics and some interesting criticisms of Aquinas.
I would also recommend Copleston’s “History of Medieval Philosophy” or “History of Philosophy” volume II as more general introductions to the era and the philosophical currents that influenced Aquinas. Dom David Knowles’ “Evolution of Medieval Thought” is another introduction to the era and is a polemaic defense of Catholicism.
For criticisms of Aquinas, Anthony Kenny, dean of Oxford and a former Catholic priest, has a number of books on Aquinas including a collection of critical essays.
If you have any questions please feel free to email me.
One more thing, you can buy used books at
www.alibris.com or
www.abebooks.com for much cheaper than at amazon. They also have a better collection of used books so many of these out of print books can be found there.
