Clearly the musician is wise, and he who is not a musician is foolish.
And he is good in as far as he is wise, and bad in as far as he is foolish?
Yes.
And you would say the same sort of thing of the physician?
Yes.
And do you think, my excellent friend, that a musician when he adjusts the lyre would desire or claim to exceed or go beyond a musician in the tightening and loosening the strings?
I do not think that he would.
But he would claim to exceed the non-musician?
Of course.
And what would you say of the physician? In prescribing meats and drinks would he wish to go beyond another physician or beyond the practice of medicine?