Having resolved the question of whether it's really even possible to seek the definition of virtue, Socrates and Meno try a new approach. Meno suggests that they return to the original question of whether virtue is taught, learned through practice, or inherent in some people's nature. Socrates, though he protests again that they should first try to discover what virtue is (rather than how it comes to people), agrees to tackle Meno's version of the question. They should do this, he suggests, by means of a hypothesis. This is a second way around the problem of seeking what one does not yet know; by proposing a possible answer to a problem ("the way geometers often carry on their investigations"), one can approach the true answer without yet knowing it (as the slave did in Socrates' examination).
Socrates proposes the following hypothesis: if virtue is a kind of knowledge, then it can be taught (and if it is not, it cannot). The next point to consider, then, is whether or not virtue is a kind of knowledge. To this end, Socrates makes a second hypothesis: if there is anything good that is not knowledge, then it is possible that virtue is not a kind of knowledge (and conversely, "if there is nothing good that knowledge does not encompass," then virtue is a kind of knowledge).
Working with these hypotheses, Socrates gives another version of his earlier point concerning the possibility of good things being used badly. Now he says that beneficial things are only so when accompanied by wisdom--"without understanding, they are harmful." This means, in effect, that virtue is only virtue when it has its context in wisdom. As Socrates puts it, "all that the soul undertakes and endures, if directed by wisdom, ends in happiness."
Thus, Socrates and Meno have already reached an important and surprising conclusion about virtue. Since virtue is "something beneficial in the soul," and since what is beneficial is only so in the context of wisdom, it would seem that "virtue...as a whole or in part, is wisdom." Socrates quickly points out that this idea has the important consequence that virtue is not inborn ("the good are not so by nature").
Meno, remembering the two hypotheses proposed by Socrates, happily concludes that, since virtue is knowledge, people must learn it by being taught. Socrates, however, is less sure. The problem is not with the hypotheses, but rather with the assertion that virtue is knowledge (a stronger proposition than the one that virtue is wisdom "as a whole or in part"). Socrates says that his suspicion lies in the following dilemma: if something as important as virtue can be taught, where are the teachers? Socrates claims (as he did at the beginning of the dialogue) that he has never yet found any such teachers. If this is truly the case, it would indicate that virtue in fact cannot be taught.
At this point, Anytus enters the conversation. A prominent Athenian citizen and respected politician, he serves as a perfect foil for Socrates' questions about public virtue and whether it can be taught. Socrates questions Anytus about the standard model for teaching--there are experts in each craft (medicine, shoemaking, etc.), and they are paid to teach these crafts to others. Socrates then suggests (facetiously, we must assume) that the equivalent expert teachers for virtue are the Sophists, who "profess to be teachers of virtue and have shown themselves to be available to any Greek who wishes to learn, and for this fix a fee and exact it."