Plato's Republic
The Republic is perhaps Plato's best-known dialogue and one of his most influential. In it, he explains, through the character of Socrates, the fundamentals of his political philosophy (presented via the conceit of a Utopia), his ethics, and his theory of universals (the 'forms')--among other things. The work is also famous for its literary style: the text is presented as a discussion between Socrates and several other students at a dinner, discussing the nature of justice.The title "Republic" is derived from the Latin title given to the work by Cicero. Plato's Greek language title, Politeia, described the government of a Polis or city-state. The character Socrates and his friends discuss the nature of an ideal city rather than the nature of the Athenian democracy.
The Republic bears little to no resemblance to the modern political institution that we, in modern times, know as the republic. Plato despises democracy (because the term was used in antiquity quite differently, viz., for mass rule that had gone haywire) and uses "The Republic" to point out some of its weaker points: susceptibility to demagogues, rule by unfit "barbarians" etc.
The ideal city as depicted in The Republic should be governed by so-called philosopher-kings as the only ones to be trusted to rule, since because of the human tendency to corruption by power and thus tyranny, ruling should only be left to those who would rather do something else (in this case, philosophize.
The city of the Republic has struck many modern critics as unduly harsh, rigid, and unfree; indeed, as a kind of prequel to modern totalitarianism. Karl Popper is perhaps the today still best-known protagonist of that view, which is the view generally represented in introductory college textbooks on political philosophy.
The perhaps most important alternative interpretation is the one suggested by Hans-Georg Gadamer in his 1934 classic, Plato und die Dichter (and several other works), in which the city of the Politeia is seen as a heuristic utopia which should not be pursued or even be used as an orientation-point for political development. Rather, its purpose is said to be to show how things would have to be connected, and how one thing would lead to another - often with highly problematic results -, if one would opt for certain principles and carry them through rigorously. This interpretation, based i.a. on the recognition of its often ironic tone (for which to detect, of course, an unusually high-level of proficiency in Greek is required), allows one to take the Politeia much more seriously, and it and Plato's entire oeuvre as much less totalitarian, than the mainstream version would suggest.
In this book, Plato also introduces his theory of forms or ideals conerning the nature of reality. The world around us is likened to the shadows cast onto the wall of a cave.