The Republic (c. 380 bc.), by Plato, is a philosophical dialogue about the nature of justice and the order and character of the just City-State and the just individual. The dialogues, among Socrates and various Athenians and foreigners, discuss the meaning of justice, and examine whether or not the just man is happier than the unjust man, by proposing a society ruled by philosopher-kings and the guardians; hence the Republic’s original Ancient Greek title: Politeía (City-State Governance). Moreover, in the dialogues, the Classical Greek philosopher Plato also discusses the theory of forms, the immortality of the soul, and the roles of the philosopher and of poetry in society. The Republic, Plato’s best-known work, proved one of the most intellectually and historically influential works of philosophy and political theory.