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When did Thomas Aquinas go to Paris?
In 1245 Thomas was sent to study at the Faculty of the Arts at the University of Paris, where he most likely met Dominican scholar Albertus Magnus
What did Thomas Aquinas study in Paris?
Then in 1252 he returned to Paris to study for the master's degree in theology.

Question: Did he study under Magnus?
Self-contained rewrite: Did Thomas Aquinas study under Magnus?