Since souls are forms of living beings, according to Aristotle, a scientific study of living beings requires first and foremost a systematic account of the soul. Such an account is supplied in the treatise De Anima, where the soul is divided into distinct parts or aspects. In this chapter it is argued that the soul is only conceptually divided, that is divided for the sake of analysis, whereas in reality each soul is a unity. The notion of conceptual division of the soul, its principles and consequences are examined, often in contrast with the spatial division of the soul advocated by Plato in the Timaeus. Conceptual division of the soul enables Aristotle to avoid the problems detected in Plato's division, and to preserve the unity both of each soul and of each organic body.
Keywords: Aristotle, De Anima, Plato, Timaeus, soul, form, matter, conceptual division, perception, living things