Plato’s short dialogue Meno — concerned with virtue and knowledge — is among the most famous of what are referred to as his “Socratic” dialogues, which dwell on Socratic method, and on the character of Socrates as a kind of role model. Meno wants Socrates to provide an easy answer to how virtue is to be acquired. Socrates, ever distrustful of easy answers, shifts the discussion toward the more basic question of what virtue is. Meno first responds with examples, but Socrates points out that examples do not answer the “what is” question.

Meno eventually suggests that virtue is the desire of honorable things, combined with the power of attaining them. Socrates then points out that some people desire evil, and that a person may have power, yet still fail to properly recognize good as good and evil as evil. Meno complains that Socrates is always doubting himself and making others doubt, and says he feels bewitched.

Socrates introduces a poetic myth that learning is a kind of recollection of knowledge that we already had. He then walks a young boy through a simple geometrical construction. At the beginning, the boy seems to have no idea how to solve the problem. Then he thinks he does, but he is wrong. At a later point, he recognizes the mistake. Socrates points out that it is always better to know that we do not know, than to think that we know when we do not. But still later, after following the steps of the construction, it seems like the boy does understand how to find the solution, though he is never told. As Brandom might remind us, this shows the value of making what was implicit into something explicit.

Eventually, Socrates leads Meno to the conclusion that virtue is “either wholly or partly wisdom”. But then he introduces a further doubt, whether virtue can be reduced to knowledge. True opinion is said to be as good a guide to action as knowledge, and this is said to be how most good people function.

But then finally, true opinion is said not to be of very great value after all, because it is not “fastened by the tie of the cause”, and therefore tends to “run away” from us. That is to say, when we do not really know — i.e., cannot articulate — the why of a conclusion that is right in one context, it is easy to misapply it in a different context. (See also Dialogue; Platonic Truth; What and Why; Reasons.)