A sixth reason for St. Thomas’ greatness is decisive only for Catholics, but it should, at least, be decisive for all Catholics: according to the Church’s own teaching authority (and to be a Catholic means to believe in such a thing), St. Thomas is the primary theological Doctor (Teacher) of the Church. During its proceedings, the Council of Trent placed the “Summa” on the high altar in second place only to the Bible. Pope Leo XIII, in “Aeterni Patris” (1879), told all Catholic teachers to “restore the golden wisdom of St. Thomas…and let them clearly point out its solidity and excellence above all other teaching.”
Even non-Catholics must go to St. Thomas to understand Catholic theology and philosophy. You can never understand a philosophy from its critics or dissenters. In four colleges and universities, I have never had a good course on any philosopher (including many philosophers I disagree with) from a critic, and never a worthless one from a disciple.
[Seventhly,] St. Thomas was crucial for the medieval era. He fulfilled, more than anyone else, the essential medieval program of a marriage of faith and reason, revelation and philosophy, the biblical and the classical inheritances. In so doing, he held together, for another century, the medieval civilization’s intellectual soul which, in his century, was threatening to break up like a ship battered by huge waves of division, caused mainly by the rediscovery of the works of Aristotle and the polarization of reactions into the fearful heresy-hunting of traditionalists and the fashionable compromising of modernists. Aquinas stands as a shining example of an alternative to both the fundamentalists and the liberals of his day, and of any day.
You may not agree that St. Thomas is history’s greatest philosopher, but he was certainly the greatest philosopher for the two thousand years between Aristotle and Descartes. He represents the medieval mind par excellence, and the Middle Ages are the parent and source of all the divergent streams in the modern world, like a mother whose many children went their own various ways.
Not only does St. Thomas represent a unity of ingredients that were later to separate, but also a unity of ingredients that existed separately before him. In reading St. Thomas you also meet Thales, Parmenides, Heraclitus, Socrates, Plato, Aristotle, Plotinus, Proclus, Justin, Clement, Augustine, Boethius, Dionysius, Anselm, Abelard, Albert, Maimonides, and Avicenna. For one brief, Camelot-like moment, it seemed that a synthesis was possible. Our fractured world has been praying “forgive us our syntheses” ever since.
From: A Summa of the “Summa”: The Essential Philosophical Passages of St. Thomas Aquinas’ “Summa Theologica” Edited and Explained for Beginners by Peter Kreeft (San Francisco: Ignatius Press, 1990), pp. 12-13.
Peter Kreeft (pronounced “craft” – with a long “a” as in “bake”) (born in 1937) has taught philosophy at Boston College since 1965.