After Homer ψυχή undergoes transformations in meaning that lead eventually to its use by Plato to designate the comprehensive personal ‘soul’—the immortal and divine part of man, the self as a center or microcosm of his whole being
Claus establishes the governing thesis: the pre-Platonic semantic history of ψυχή is the necessary foundation for understanding how Plato’s doctrine of the soul represents a radical transformation rather than a simple inheritance.
, Toward the Soul: An Inquiry into the Meaning of Psyche before Plato, 1981thesis