SOCRATES: ...suppose I asked you what a bee is, what is its essential nature, and you replied that bees were of many different kinds. What would you say if I went on to ask, And is it in being bees that they are many and various and different from one another? Or would you agree that it is not in this respect that they differ, but in something else, some other quality like size or beauty?
MENO: I should say that in so far as they are bees, they don’t differ from one another at all. Plato, Meno, 72b.
Meno is a young man visiting Athens from the region of Thessaly. Meno is a student of Gorgias, the famous teacher of rhetoric. Gorgias (who appears himself in yet another dialogue named after him) and all such teachers (they were called the Sophists) are rivals of Socrates. While the Sophists give their students pat answers, Socrates encourages the men who come to him to think for themselves.
In this dialogue, which we call “Meno” after Socrates’ primary interlocutor, Meno asks Socrates for pat answers: Is virtue taught, acquired by practice, something innate, or something else? Socrates flips the question back: What is virtue? What is it about virtues --courage, justice, wisdom-- which make them virtues? What is virtue qua virtue?
The Greek word translated as "virtue" is arete (excellence), but as the dialogue develops it is not about “excellence” but about epistemology, how we know what we know. Today, a discussion of epistemology would likely use mathematics or science as examples of things useful and important to learn and know, and knowledge is considered an object or possession. In this dialogue, the things to be learned are personal qualities, and it makes as much sense to ask whether they are innate or acquired in action, or even absorbed by association with virtuous people.
That distinction noted, the most memorable part of this dialogue concerns the demonstration of mathematical facts. Socrates demonstrates that a slave boy of Meno’s household can learn certain facts of geometry (a subset of the Pythagorean theorem: that the diagonal of a square produces a square twice the area of the original square: h2 = 2a2).
Meno believes things can be learned from a teacher. Since the slave boy does not have the benefit of a teacher (only aristocrats like Meno could afford education) Socrates claims to have proved a theory of “recollection”, which is a kind of theory of reincarnation: that our “souls” are immortal and the slave boy must have had a teacher in a prior life.
The doctrine of recollection is, of course, meant ironically as something like a joke. If we only “recollect” what we learned in a prior lifetime, how did we learn it then? Only someone blinded by a preconceived notion, like Meno, would have failed to notice how Socrates leads the boy by his questions and by pointing to the diagram drawn in the sand. This is the point of the exercise: just as the slave boy cannot learn the truth until he learns that the obvious answer is wrong (that the area of a square is not directly proportional to the length of a side), Meno also has to be lead away from his preconception that virtue can be learned by memorizing the precepts of the wise.
Socrates concludes that virtue cannot be taught and that it is acquired by divine dispensation and inspiration, noting however, that the discussion has likely not arrived at the truth of the matter because the question “What is virtue?” was not answered first.
The Collected Dialogues of Plato, Ed. Edith Hamilton and Huntington Cairns (Princeton, 1961); Meno tr. W.K.C. Guthrie.
Note that Plato is cited by using "Stephanus" numbers, which are from the pages of a authoritative Greek text published in Geneva in 1578 by the printer and humanist, Henri Estiene (Stephanus). The Stephanus numbers appear in the margins of my big green Collected Dialogues, and any useful edition of Plato.