he does not know anything of medicine.
Then he who has this knowledge will not be able to ex-Exactly.
amine whether a pretender knows or does not know that Then the wise man may indeed know that the physician which he says that he knows: he will only know that he has has some kind of science or knowledge; but when he wants a knowledge of some kind; but wisdom will not show him to discover the nature of this he will ask, What is the sub-of what the knowledge is?
ject-matter? For the several sciences are distinguished not Plainly not.
by the mere fact that they are sciences, but by the nature of Neither will he be able to distinguish the pretender in their subjects. Is not that true?
medicine from the true physician, nor between any other Quite true.
true and false professor of knowledge. Let us consider the And medicine is distinguished from other sciences as hav-matter in this way: If the wise man or any other man wants ing the subject-matter of health and disease?
to distinguish the true physician from the false, how will Yes.
he proceed? He will not talk to him about medicine; and And he who would enquire into the nature of medicine that, as we were saying, is the only thing which the physi-must pursue the enquiry into health and disease, and not cian understands.
into what is extraneous?
True.