Theaetetus (167)

SOC.Now neither of these two is to be made wiser than he is—that is not possible— nor should the claim be made that the sick man is ignorant because his opinions are ignorant, or the healthy man wise because his are different; but a change must be made from the one condition to the other, for the other is better. So, too, in education a change has to be made from a worse to a better condition; but the physician causes the change by means of drugs, and the teacher of wisdom by means of words. And yet, in fact, no one ever made anyone think truly who previously thought falsely, since it is impossible to think that which is not or to think any other things than those which one feels; and these are always true. But I believe that a man who, on account of a bad condition of soul, thinks thoughts akin to that condition, is made by a good condition of soul to think correspondingly good thoughts; and some men, through inexperience, call these appearances true, whereas I call them better than the others, but in no wise truer. And the wise, my dear Socrates, I do not by any means call tadpoles when they have to do with the human body, I call them physicians, and when they have to do with plants, husbandmen; for I assert that these latter, when plants are sickly, instil into them good and healthy sensations, and true ones instead of bad sensations, and that the wise and good orators make the good, instead of the evil, seem to be right to their states. For I claim that whatever seems right and honorable to a state is really right and honorable to it, so long as it believes it to be so; but the wise man causes the good, instead of that which is evil to them in each instance, to be and seem right and honorable. And on the same principle the teacher who is able to train his pupils in this manner is not only wise but is also entitled to receive high pay from them when their education is finished. And in this sense it is true that some men are wiser than others, and that no one thinks falsely, and that you, whether you will or no, must endure to be a measure. Upon these positions my doctrine stands firm; and if you can dispute it in principle, dispute it by bringing an opposing doctrine against it; or if you prefer the method of questions, ask questions; for an intelligent person ought not to reject this method, on the contrary, he should choose it before all others. However, let me make a suggestion: do not be unfair in your questioning; it is very inconsistent for a man who asserts that he cares for virtue to be constantly unfair in discussion; and it is unfair in discussion when a man makes no distinction between merely trying to make points and carrying on a real argument.