Plato on the Parts of the Soul

Abstract

To establish a tripartite division of the parts of the soul, Socrates in Plato's Republic introduces a Principle of Opposites. The principle entails that only distinct parts of a soul can be simultaneously engaged in opposed actions directed toward the same intended object. Appealing to the principle, Socrates proposes to distinguish between rational, spirited, and appetitive parts of the soul. He describes two situations of opposed actions in a soul that both desires to drink but chooses not to drink, and desires to indulge in morbid voyeurism but is angry about doing so. Without a sound basis for dividing the parts of the soul in precisely this way, Socrates cannot adequately defend the dialogue's main conclusion that justice in both city and soul is the proper harmonious hierarchical order of their respective parts. I argue that Socrates' efforts to prove the division of the soul into three parts are inconclusive because it is possible to interpret his illustrations as involving unopposed psychological acts directed toward different rather than identical intended objects.