At the outset of Book III, Socrates declares the topic will be focused on “the gods”, or the stories, the education, of the citizens of the city.
First, we encounter the education of the guardians of the city. The guardians must be taught to lack fear and must also be taught to avoid excessive laughter. The purpose of their education is to acquire eros of virtue and courage and moderation, for the good of the city. There is a certain quality of oneness and wholeness to their education, and therefore in the justice of the city which is worth considering in preserving the link between the just individual and the just city, a link that was created by Socrates in Book II. At any rate, it is established that the rulers will need to lie for the sake of the city, as the truth does not necessarily benefit the gods and the citizens need not be involved with every truth of the city. Therefore, they must be lied to, for the good of the city.
Socrates and Glaucon discuss the regulation of, and eventual banishment, of the poets from the city. Curiously, the poets are accused of being untruthful and inaccurate, however the rulers will be called upon to lie. The city, and its continuation, will rely on some form of untruth. Education, particularly for the guardians, will not include the contemporary poets. The appropriate education of the guardians will instead include simple forms of music and gymnastics, both to exercise the soul toward an eros for virtue and moderation. Neither is to be practiced in excess.
From the crop of guardians, we must now find the rulers. Socrates persuades Glaucon that they must watch these elite guardians from youth to see that they will not be easily deceived and must have a strong memory. They are to be perfect gentlemen rulers and defenders of the city. From this group, they will select the best of men.
Next, in the most important section of Book III, Socrates hesitantly proposes that he and Glaucon devise a “noble lie” (414b) that will in the best case persuade both the rulers and the citizens of the city, but if not the rulers, then at least the rest of the whole city. His proposition is not a new thing, but an old Phoenician, something that requires a great deal of persuasion. The “Phoenician thing” most likely refers to the Phoenician story of Cadmus who founded the city of Thebes with giants and teeth of a slain dragon. The noble lie is ancient thing, not possible in our present state of decay, brought to rebirth in the city in speech.
The noble lie devised by Socrates has two parts. First, Socrates persuades the rulers and the guardians that they were born of the earth, but not of all the earth, rather they are connected to one particular place. A part of their earth and connected to their fellow citizens as brothers. They are not find a universal kinship among all peoples. In the second part, there is a kind of natural hierarchy that is reinforced by “the god”. The citizens are divided among the gold breed and the silver breed. The gold are fashioned by the god (and they are not necessarily born gold to gold). Natural hierarchy is inevitable. Iron and bronze are reserved for the farmers and other craftsmen.
Lastly, in Book III, Socrates and Glaucon discuss the appropriate place for the military camp of the guardians because they must be like trained wolves, rather than dogs. They must not turn on the sheep, but rather protect their flock, though they are stronger. First Socrates eliminates private property and second, all will be allowed to come in and out of each other’s houses as they please. Thus, the birth of pure communism is to be the safeguard of the guardians against the city.