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."
Anytus is shocked by the suggestion--he hates the Sophists, who "clearly cause the ruin and corruption of their followers." (This opinion of the Sophists was widely held at the time, though they were well-respected enough as teachers of rhetoric to keep them employed and even to give them some degree of fame. Socrates' own eventual execution was due in part to a perceived similarity to the Sophists, though he argued against them his whole life.) Socrates pretends to be amazed at Anytus' disapproval, in order to point out that Sophists like Protagoras have gained fame and been well-respected (and well-paid) for over forty years. This kind of error in judgment, he says, could never happen with teachers of common crafts, so how could it be so with regard to professed teachers of virtue?
In any case, says Socrates, the question is who can teach us virtue, not who can't--"let them be the Sophists if you like." Anytus suggests that one need only to talk to any "gentleman" on the streets of Athens to see true virtue, but Socrates redirects his answer to his and Meno's original question about whether virtue can be taught: "have [these gentlemen] been good teachers of their own virtue?"
Socrates gives this question some more weight for the prominent Anytus by citing examples of virtuous, well-respected men whose sons have turned out less than perfect: Themistocles and his son Cleophantus, Pericles and his sons Paralus and Xanthippus, Aristides and his son Lysimachus, and Thucydides and his sons Melesias and Stephanus. In each case, Socrates argues, the fathers taught their sons to the utmost of their abilities (since they were virtuous men), and certainly "would have found the man who could make [their sons] good men." If virtue could be taught at all, it would have been in these cases. Yet this apparently did not happen.
Anytus finally gets angry at hearing all of these honorable personages slandered and warns Socrates to be careful. But Socrates blithely continues, asking Meno if he has run across any fellow Thessalians who claimed to teach virtue. Meno replies that his people disagree about whether virtue can be taught at all (perhaps the reason he asked Socrates in the first place). Socrates than asks Meno again about the Sophists--are there any, even Gorgias, who claimed to teach virtue? Meno replies that he particularly respects Gorgias for his refusal to claim to teach anything other than how to be a "clever speaker."
Even the poet Theognis, Socrates now recalls, could not decide whether virtue is teachable or not; Socrates recites two brief passages from him that contradict each other on this issue. "Would you say," asks Socrates, summing up the dilemma, "that people who are so confused about a subject can be effective teachers of it?" The answer is clearly no.
Thus, despite concluding earlier that virtue is at least partly a kind of wisdom (though not necessarily "knowledge" per se), it would now appear that virtue cannot be taught at all, and therefore that it is not knowledge. This is a disturbing picture of things, since it means that "it is not only under the guidance of knowledge that men succeed in their affairs."