Plato's “Republic” Book III: A Regime founded on Gymnastics, “Music”, and Lies.

In this chapter Socrates' inner circle fills in the outline given in Book II of the ideal state.
Since the main castes of the ideal state must have a suitable character that differs from the that found in most Greek cities, Socrates proposes that they must be properly educated, which means that they must study only good things and be denied the bad. Thus he outlines the first detailed system of censorship based not on personal reputation or vanity but on principle. While most modern people (excluding fascists and Communists) are highly critical of this program, keep in mind it is primarily for the ruling classes who are also denied the right to have and spend money or hold any private property.
After this Plato concocts a religious dogma that will persuade believers to support the ideal state.