De Anima

The soul is, so to speak, the first principle of living things. We seek to contemplate and know its nature and substance. For Pre-Socratic philosophers, the soul was the source of movement and sensation, while for Plato, it was the seat of being, metaphysically distinct from the body. Aristotle examined these beliefs against the emerging sciences of logic and biology, convincing him of the inadequacy of both materialist reduction and Platonic sublimation. In De Anima, he set out his theory of the soul as the ultimate reality of embodied form, providing a masterpiece of philosophical insight and a psychology of fascinating subtlety.