Plato 
The Republic 

The Republic is a Socratic dialogue, authored by Plato around 375 BC, concerning justice, the order and character of the just city-state, and the just man. Written after the Peloponnesian War, The Republic reflected Plato’s perception of politics as a dirty business that sought mainly to manipulate the unthinking masses. It failed to nurture wisdom. It starts out as a dialogue between Socrates several young men on the nature of justice. It’s a classic for good reason, so if you’re interested in ancient philosophy/politics at all, it’s a must read. … The revolutionary thing about Socratic philosophy (and Plato picked up part of the lesson at least) is that it encouraged real dialogue. And we’ve been talking about it ever since.