Thomas Aquinas

The greatest synthesizer of the Christian intellectual tradition. A Dominican friar so quiet his classmates called him "the dumb ox" — until his teacher Albertus Magnus said, "this ox will fill the world with his bellowing." His Summa Theologiae attempts the impossible: to organize all of Christian thought into a single argument, in dialogue with Aristotle, the Church Fathers, and Jewish and Muslim philosophers. His insistence that grace perfects nature rather than destroying it became the backbone of Catholic theology. Near the end of his life, after a mystical experience while saying Mass, he stopped writing entirely. "All that I have written," he said, "seems to me like straw compared to what has now been revealed to me."