The Republic — who's who

Plato's Socrates, here in the early evening of his life. He has gone down to the Piraeus for a religious festival and is detained, half-jokingly, by friends who want to talk. He talks. By the dialogue's end he has constructed an entire ideal city, dismantled four corrupt regimes, defined the soul, and ended in myth. Throughout he asks more than he answers; the dialogue's positive doctrines all emerge from questions he puts to others.

The chief interlocutor for most of the dialogue. Glaucon is sharp, ambitious, well-bred — Plato never stops calling him beautiful — and willing to push Socrates into hard places. The ring-of-Gyges challenge in Book Two is his; it is the engine that drives the rest of the work. Glaucon is Socrates's preferred interlocutor because he will accept no easy answer.

Glaucon's quieter older brother. He takes over the conversation in the more practical stretches — the education of the guardians, the place of poetry, the politics of the city. He is more skeptical than Glaucon about the city-in-speech and presses Socrates harder on whether any of this could ever be real.

A professional rhetorician who has been listening with growing impatience to Socrates question Polemarchus. He breaks in with the cynical and uncomfortable claim that justice is the advantage of the stronger. Socrates takes him apart over the course of Book One — but Thrasymachus is not destroyed, only partly tamed; he stays in the room for the rest of the night, and at the end of Book One Socrates compliments him on becoming gentle.

Son of Cephalus, the dialogue's host. He inherits the argument when his father leaves and offers the early definition that justice is helping friends and harming enemies — an answer Socrates dismantles by asking whether one always knows who one's friends are. Polemarchus is decent, sincere, not very subtle, and the easiest target.

Polemarchus's elderly father. He opens the dialogue with grace and the easy answer — justice is paying your debts and telling the truth. Then he leaves to attend a sacrifice. His departure is the moment the dialogue gets serious. Cephalus represents the unexamined life lived well — for which Plato has affection but, ultimately, no philosophical use.

The Republic is presented as Socrates narrating, the day after, what was said the night before. Plato is nowhere in it — he is the unseen artist behind the curtain. Knowing he was Glaucon and Adeimantus's younger brother gives the dialogue a strange autobiographical edge: he is letting his older brothers speak for him while staying offstage.

Homer haunts the Republic. He is invoked in Book Two as the source of the bad theology that has to be reformed; in Book Three as the great teacher of imitation that has to be restricted; in Book Ten as the chief of the poets who must be expelled from the city. Socrates says he loves Homer — and banishes him anyway.