Yeah, that must be it. I never heard of Aquinas or Aristotle. Either that or it’s this, from Norman Cantor’s The Civilization of the Middle Ages:
The “Summa Theologica was the major turning point in thirteenth-century thought, a breakthrough of first importance. But it was one that startled and disturbed as many of his contemporaries as it satisfied. Nothing is further from the reality of thirteenth-century culture than to imagine that Thomism was immediately acclaimed by all as the answer to the intellectual problems of the church. Modern Catholicism may regard Thomism as the official philosophy of the church, but this is far from the attitude that prevailed in St. Thomas’s day and for the next two centuries. Thomas was regarded by many as a radical, highly speculative, and tendentious thinker.”
“Ultimately medieval theologians were unable to establish a common view of either the divine or the natural aspects of the Christian universe. The attempt by Thomas Aquinas to argue from the natural to the divine and thus to reconcile Aristotelian metaphysics with the Christian concept of God found opponents on every side. St. Bonaventura and his followers rejected Aquinas’s argument that man can arrive at a rational, if imperfect, knowledge of God by analogy from the natural world, arguing that knowledge of God comes from mystical communion with the divine, not from nature. On the other hand, the Christian followers of Averroes—the most distinguished Muslim commentator on the Aristotelian corpus—argued that man’s only sure knowledge comes from nature and that consequently he can have no secure knowledge of God by exercising reason…
“The major outcome of the great Thomist age of synthesis was a reaction against it that shook scholastic philosophy to its foundations. As the fluid and even amorphous body of Christian doctrine that existed in the twelfth and thirteenth centuries was subjected to the dual impact of Aristotle and the social and political disorders of the fourteenth century, the medieval worldview began gradually to break down. The philosophical issues bequeathed by the thirteenth century to the fourteenth proved impossible to solve.”
Thus, the introduction of Aristotelian naturalism into Christendom was a proto-modern development, Aquinas’s attempt at integration notwithstanding.
