One achievement of st. thomas aquinas was

Reconciling Aristotle's logic with principles of the Roman Catholic faith.

Explanation:

Saint Thomas Aquinas was an Italian priest and philosopher. He was extremely influential during his time and throughout the history of philosophy. He was a father of Thomism, which is a philosophy that argues that reason is found in God. One of his most important accomplishments was the synthesizing of Aristotelian philosophy with the Roman Catholic faith.

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