Overview
Republic is a Socratic dialogue, authored by Plato around 375 BCE, concerning justice, the order and character of the just city-state, and the just man. It is Plato's best-known work, and one of the world's most influential works of philosophy and political theory, both intellectually and historically.
In the dialogue, Socrates discusses the meaning of justice and whether the just man is happier than the unjust man with various Athenians and foreigners. He considers the natures of existing regimes and then proposes a series of hypothetical cities in comparison, culminating in Kallipolis (Καλλίπολις), a utopian city-state ruled by a class of philosopher-kings. They also discuss ageing, love, theory of forms, the immortality of the soul, and the role of the philosopher and of poetry in society. The dialogue's setting seems to be the time of the Peloponnesian War.
Place in Plato's corpus
Republic is generally placed in the middle period of Plato's dialogues. However, the distinction of this group from the early dialogues is not as clear as the distinction of the late dialogues from all the others. Nonetheless, Ritter, Arnim, and Baron—with their separate methodologies—all agreed that the Republic was well distinguished, along with Parmenides, Phaedrus and Theaetetus.
However, the first book of the Republic, which shares many features with earlier dialogues, is thought to have originally been written as a separate work, and then the remaining books were conjoined to it, perhaps with modifications to the original of the first book.
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