Historical context
On the Soul (Latin De Anima) is Aristotle's treatise on the nature of life and mind, and the platform reads it as the founding work of the philosophy of mind and of psychology as a discipline. It belongs to his vast project of understanding the natural world — the same empirical, biological spirit that produced his pioneering works on animals — turned here to the most fundamental question about living things: what is the soul (psychē), the principle that makes the difference between the living and the dead?
Central argument
The platform reads the work's central claim as Aristotle's distinctive answer, which differs sharply from Plato's. The soul is not, for Aristotle, a separate immaterial substance temporarily lodged in the body (as in the Phaedo); it is the form of the living body — its organization, its function, "the first actuality of a natural body that has life potentially." Soul and body are related as form and matter, inseparable as the shape of a statue is inseparable from its bronze. He then analyses the soul as a hierarchy of faculties: the nutritive (shared by all living things, plants included), the sensitive (shared by animals — perception, desire, movement), and the rational (distinctive of human beings — thought and intellect). The platform reads this under teleology: each faculty is understood by its function and its end.
Significance
The platform reads On the Soul as one of the most influential texts in the history of philosophy and the deepest point of difference between Aristotle and Plato on the nature of the human person. Aristotle's view that the soul is the form of the body — neither a ghost in the machine nor a mere by-product of matter — anticipates much of modern philosophy of mind and remains a serious option in the debate over the relation of mind and body. His analysis of perception (the sense receiving the form of the perceived without its matter) and of intellect (including the famously difficult "active intellect") set the agenda for the subject for two thousand years.
Reception and influence
The platform reads On the Soul as central to medieval philosophy and theology, where its account of the soul as the form of the body had to be reconciled, by Aquinas and others, with the Christian doctrine of personal immortality — a reconciliation that produced some of the most subtle philosophy of the Middle Ages. The platform reads it as the natural-philosophical counterpart to Aristotle's ethics (the soul whose excellent activity is flourishing) and as the text in which the difference between the two great Greek philosophers on the human person is sharpest, read in Aristotle versus Plato.