Aristotle (384–322 B.C.E.) The first Western thinker to study psychological topics, Aristotle combined the logic of philosophy with empirical observation. His best-known psychological work, De Anima, is regarded as the first systematic treatise on psychology. Its topics included such basic psychological processes as the senses, perception, memory, thinking, and motivation. Aristotle’s writings on psychology anticipated topics and theories that would be central to scientific psychology centuries later.

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