Philosopher · Antiquity
Aristotle
384–322 BC · Aristotelianism
Pagan philosopher; “the Philosopher” of St. Thomas and the medieval schools.
Plato's greatest pupil and tutor of Alexander. He grounded knowledge in sense experience and abstraction, explained change by form, matter and the four causes, argued to an unmoved first mover who is pure act and thought thinking itself, and built ethics on virtue, practical wisdom and happiness as the activity of the soul in accordance with virtue.
Why he matters: Received through Boethius, the Arabs and St. Albert, Aristotle became the philosophical backbone of St. Thomas and of the Church's own doctrinal language: substance and accident, nature, act and potency, the soul as form of the body, the natural law.
Where to be careful
He held the world to be eternal, had no doctrine of creation or of personal providence, and left the individual immortality of the soul unclear; the Latin Averroists who followed him on these points were condemned at Paris in 1270 and 1277.
Documented positions
Where this thinker stands on each dispute the test covers.