An essay on Pietro Pomponazzi, the philosopher and founder of the Aristotelian-Averroistic School. His great work De immortalitate animi, gave rise to a storm of controversy between the orthodox Thomists of the Catholic Church, the Averroists headed by Agostino Nifo, and the so-called Alexandrist School. The treatise was burned at Venice, and Pomponazzi himself ran serious risk of death at the hands of the Catholics. Two pamphlets followed, the Apologia and the Defensorium, wherein he explained his paradoxical position as Catholic and philosophic materialist. His last two treatises, the De incantationibus and the De fato, were posthumously published in an edition of his works printed at Basel. Chapters: Aristotle in the Early Middle Ages; The Arabians and St. Thomas; Pomponazzi as an Aristotelian; Pomponazzi's Psychology; The Soul; Intelligence; Sense; Reason; Knowledge; The Nature of Virtue; and Natural Law in Human Life and Religion.