Tyrants preserve themselves by sowing fear and mistrust among the citizens by means of spies, by distracting them with foreign wars, by eliminating men of spirit who might lead a revolution, by humbling the people, and making them incapable of decisive action.
Even if we could suppose the citizen body to be virtuous, without each of them being so, yet the latter would be better, for in the virtue of each the virtue of all is involved.
If a man of good natural disposition acquires Intelligence [as a whole], then he excels in conduct, and the disposition which previously only resembled Virtue, will now be Virtue in the true sense. Hence just as with the faculty of forming opinions [the calculative faculty] there are two qualities, Cleverness and Prudence, so also in the moral part of the soul there are two qualities, natural virtue and true Virtue; and true Virtue cannot exist without Prudence.
But since there is but one aim for the entire state, it follows that education must be one and the same for all, and that the responsibility for it must be a public one, not the private affair which it now is, each man looking after his own children and teaching them privately whatever private curriculum he thinks they ought to study.
Between friends there is no need for justice, but people who are just still need the quality of friendship; and indeed friendliness is considered to be justice in the fullest sense.
Again, the male is by nature superior, and the female inferior; and the one rules, and the other is ruled; this principle, of necessity, extends to all mankind.