The Republic, a fictional dialogue between Socrates and other various Athenians and foreigners, is widely considered as Plato’s most famous work and one of the most important books ever written on the subject of philosophy and political theory. This Socratic dialogue written around 380 BC examines the meaning of justice, the order and character of the just city-state, as well as the just man. In the book, Socrates along with various Athenians and foreigners discuss the meaning of justice and examine whether or not the just man is happier than the unjust man by considering a series of different cities coming into existence "in speech", culminating in a city called Kallipolis, which is ruled by philosopher-kings; and by examining the nature of existing regimes. Because it centered in the definition and examination of justice, ancient readers used “On Justice” as an alternative title of the book (not to be confused with the spurious dialogue also titled On Justice).
As Plato's best-known work, it has proven to be one of the most intellectually and historically influential works of philosophy and political theory. The book discusses Plato's "Theory of Forms", the nature of the philosopher, the conflict between philosophy and poetry, and the immortality of the soul. The participants also discuss the theory of forms, the immortality of the soul, and the roles of the philosopher and of poetry in the society.
Although the dramatic date of the dialogue has been much debated and though it might have taken place during the Peloponnesian War, "there would be jarring anachronisms if any of the candidate specific dates between 432 and 404 were assigned". Regardless of the disagreements, The Republic is a monumental work of antiquity, which forms the foundation of our modern policy. It is a must-read by any student of philosophy or political science.