Abstract
I propose to examine the figure of the daimōn as it appears in the myth of Er (Plato, Republic X, 617e, 620d-e), by relating it to the literary tradition prior to Plato, in particular lyric poetry (in Theognis and Pindar) and tragedy, notably in Euripides. I will show how Plato engages in a polemical dialogue with this heritage, modifying certain traditional representations of the daimōn in order to adapt them to his philosophical demands.