The Republic · Rep. 440e–441a

But a further question arises: Is passion different from reason also, or only a kind of reason; in which latter case, instead of three principles in the soul, there will only be two, the rational and the concupiscent; or rather, as the State was composed of three classes, traders, auxiliaries, counsellors, so may there not be in the individual soul a third element which is passion or spirit, and when not corrupted by bad education is the natural auxiliary of reason?

Plato · translated by Benjamin Jowett · composite transcription based on the 1888 third edition
Benjamin Jowett, revised third edition (1888), with Stephanus numbering from the 1908 edition; composite transcription, Project Gutenberg #55201
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