Hence intellect[ual perception] is both a beginning and an end, for the demonstrations arise from these, and concern them. As a result, one ought to pay attention to the undemonstrated assertions and opinions of experienced and older people, or of the prudent, no less than to demonstrations, for, because the have an experienced eye, they see correctly.
Suppose, then, that all men were sick or deranged, save one or two of them who were healthy and of right mind. It would then be the latter two who would be thought to be sick and deranged and the former not!
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.
In seeking for justice men seek for the mean or neutral, for the law is the mean. Again, customary laws have more weight, and relate to more important matters, than written laws, and a man may be a safer ruler than the written law, but not safer than the customary law.
Since the whole city has one end, it is manifest that education should be one and the same for all, and that it should be public, and not private - not as at present, when every one looks after his own children separately, and gives them separate instruction of the sort which he thinks best; the training in things which are of common interest should be the same for all. Neither must we suppose that any one of the citizens belongs to himself, for they all belong to the state, and are each of them a part of the state, and the care of each part is inseparable from the care of the whole.