So the medical man knows nothing about medicine either, since medicine is, of course, a science. True. Then the temperate man will know, indeed, that the doctor has a certain science; but when he has to put its nature to the proof, must he not consider what its subjects are? Is not each science marked out, not merely as a science, but as a particular one, by the particular subjects it has? It is, to be sure. And medicine is marked out as different from the other sciences by being a science of health and disease. Yes. And so anyone who wishes to inquire into medicine must make those things, whatever they may be, with which it is concerned, the matter of his inquiry; not those foreign things, I presume, with which it is not? No, indeed. Then he who conducts his inquiry aright will consider the doctor, as a medical man, in connection with cases of health and disease. So it seems. And will inquire whether, in what is said or done in such cases, his words are truly spoken, and his acts rightly done? He must. Well now, could anyone follow up either of these points without the medical art? No, indeed. Nobody at all, it would seem, but a doctor; and so not the temperate man either: for he would have to be a doctor, in addition to his temperance.That is so. Then inevitably, if temperance is only a science of science and of lack of science, it will be equally unable to distinguish a doctor who knows the business of his art from one who does not know but pretends or thinks he does, and any other person who has knowledge of anything at all: one will only distinguish one’s fellow-artist, as craftsmen usually can. Apparently, he said. Then what benefit, I asked, Critias, can we still look for from temperance, if it is like that? For if, as we began by assuming, the temperate man knew what he knew and what he did not know, and that he knows the one and does not know the other, and if he were able to observe this same condition in bother man, it would be vastly to our benefit, we agree, to be temperate; since we should pass all our lives, both we who had temperance and all the rest who were governed by us, without error. For neither should we ourselves attempt to do what we did not know, instead of finding out those who knew and placing the matter in their hands, nor should we permit others under our governance to do anything but what they were likely to do aright; and they would do that when they had knowledge of it; and so it would be that a house which was ordered, or a state which was administered, as temperance bade, and everything else that was ruled by temperance, could not but be well ordered;