Forage Plato · Republic
Plato

Republic

Πολιτεία

The Republic begins with a simple question at a dinner in the Piraeus, the port of Athens: what is justice, and is a just person happier than an unjust one? To answer it, Socrates and his companions build an ideal city in words, and find the same structure in the human soul.

Along the way come some of the most famous images in philosophy: the ring of Gyges, the philosopher-kings, the sun, the divided line, the cave, and the myth of Er. It is Plato’s longest and most ambitious work, and the one that has shaped Western thought about politics, education and the good life more than any other.

Socrates narrates the whole conversation himself. Each of the ten books is on its own page.

Greek text: John Burnet, Platonis Opera, vol. 4 (Oxford), via the Perseus Digital Library, CC BY-SA 4.0. English: translated from the Greek with AI (Claude), then edited for accuracy and consistency. Not reviewed by a human specialist. Free to reuse under CC BY-SA 4.0. Margin numbers are the standard Stephanus references.

About Plato

Plato (about 428–348 BC) was an Athenian philosopher, a follower of Socrates, and the founder of the Academy, a school in Athens. His dialogues, most with Socrates as the main speaker, are among the founding texts of Western philosophy.

Who’s who

Socrates
The narrator, who retells a long conversation held at a house in the Piraeus.
Glaucon
Plato’s older brother, eager and sharp, Socrates’ main partner from Book II on.
Adeimantus
Plato’s other brother, who joins Glaucon in challenging Socrates to defend justice.
Cephalus
A wealthy, elderly resident of the Piraeus, the host, who talks about old age and money.
Polemarchus
Cephalus’ son, who defends the view that justice is helping friends and harming enemies.
Thrasymachus
A sophist from Chalcedon who argues angrily that justice is the advantage of the stronger.
Clitophon
A companion of Thrasymachus who briefly speaks up for him.
Lysias
Cephalus’ son, later a famous speechwriter, present but silent.
Simonides
A lyric poet whose saying about justice Polemarchus defends.
Homer
The epic poet, whose portrayal of gods and heroes Socrates criticizes.
Hesiod
An early poet, criticized alongside Homer for false stories about the gods.
Gyges
A shepherd in Glaucon’s story who finds a ring that makes him invisible and seizes a throne.
Er
A soldier who, in the closing myth, comes back to life and reports what happens to souls after death.

Key terms

justice δικαιοσύνη dikaiosynē
The main question of the book. It turns out to be each part of a city or soul doing its own work.
injustice ἀδικία adikia
The opposite of justice. Thrasymachus and Glaucon argue that the unjust life pays better.
the advantage of the stronger τὸ τοῦ κρείττονος συμφέρον to tou kreittonos sympheron
Thrasymachus’ definition of justice: whatever benefits those in power.
constitution πολιτεία politeia
A city’s form of government and way of life; also the Greek title of the book.
guardians φύλακες phylakes
The ruling class of the ideal city, trained from childhood. They include the rulers and the auxiliaries.
auxiliaries ἐπίκουροι epikouroi
The guardians who defend the city and enforce the rulers’ decisions, like soldiers.
philosopher φιλόσοφος philosophos
A lover of wisdom. Socrates argues that cities will not be free of trouble until philosophers rule.
the reasoning part τὸ λογιστικόν to logistikon
The part of the soul that thinks and should rule the others.
the spirited part τὸ θυμοειδές to thymoeides
The part of the soul that feels anger and cares about honor; it should side with reason.
the appetitive part τὸ ἐπιθυμητικόν to epithymētikon
The part of the soul that wants food, drink, sex, and money.
moderation σωφροσύνη sōphrosynē
Self-control; in the city and the soul, agreement among the parts about which should rule.
the form of the good ἡ τοῦ ἀγαθοῦ ἰδέα hē tou agathou idea
The highest object of knowledge, compared to the sun: it makes everything else knowable.
forms εἴδη / ἰδέαι eidē / ideai
The unchanging realities, such as justice itself, that philosophers know and ordinary things resemble.
knowledge ἐπιστήμη epistēmē
Grasp of what truly is. Socrates contrasts it with opinion and gives it only to philosophers.
opinion δόξα doxa
Belief about the changing world of appearances; it falls between knowledge and ignorance.
imitation μίμησις mimēsis
Copying the appearance of things, as poets and painters do. Book X argues it is far from the truth.