Plato's conception of the soul

The Greek word that is commonly translated “soul”, psuchē, means the principle of life in a living thing. It does not necessarily imply dualism: the view that the soul is something distinct from and independent of the body. Nevertheless, Plato's conception of the soul was dualist; he regularly distinguishes and opposes soul and body. This seems to have been quite normal in his time. Even philosophers whose general view of the world was materialistic often thought of the soul as a special kind of body, rather than a state or aspect of ordinary bodies. Plato's Socrates does at one point, in the Phaedo (85e–6d), discuss a theory that is closer to materialism in a modern sense, according to which the soul is the “harmony” of the body, the way in which the constituent elements in it are combined, but this theory is quite swiftly rejected (91cff.). Most of the time dualism is taken for granted. However, Plato does not see dualism as immediately implying that the soul is immortal. This is a further claim that for him needs argument.

Plato's position on what functions and capacities belong to the soul varies from one work to another. In the Phaedo he assigns only rational activities to the soul; perception, irrational desire and even belief belong to the body, and for this reason there can be a conflict between soul and body (94b).