Sometime back in the 16th century, we borrowed the word psyche directly from Greek into English. In Greek mythology, Psyche was a beautiful princess who fell in love with Eros (Cupid), god of love, and went through terrible trials before being allowed to marry him. The story is often understood to be about the soul redeeming itself through love. (To the Greeks, psyche also meant "butterfly", which suggests how they imagined the soul.) In English, psyche often sounds less spiritual than soul, less intellectual than mind, and more private than personality.