Plato, Meno 93a

ἔμαθον; καὶ τούτους ἔγωγε ἀξιῶ παρὰ τῶν προτέρων μαθεῖν, ὄντων καλῶν κἀγαθῶν· ἢ οὐ δοκοῦσί σοι πολλοὶ καὶ ἀγαθοὶ γεγονέναι ἐν τῇδε τῇ πόλει ἄνδρες; ἔμοιγε, ὦ Ἄνυτε, καὶ εἶναι δοκοῦσιν ἐνθάδε ἀγαθοὶ τὰ πολιτικά, καὶ γεγονέναι ἔτι οὐχ ἧττον ἢ εἶναι· ἀλλὰ μῶν καὶ διδάσκαλοι ἀγαθοὶ γεγόνασιν τῆς αὑτῶν ἀρετῆς; τοῦτο γάρ ἐστιν περὶ οὗ ὁ λόγος ἡμῖν τυγχάνει ὤν· οὐκ εἰ εἰσὶν ἀγαθοὶ ἢ μὴ ἄνδρες ἐνθάδε, οὐδʼ εἰ γεγόνασιν ἐν τῷ

what they did not learn themselves? I expect they must have learnt in their turn from the older generation, who were gentlemen: or does it not seem to you that we have had many good men in this city? Yes, I agree, Anytus; we have also many who are good at politics, and have had them in the past as well as now. But I want to know whether they have proved good teachers besides of their own virtue: that is the question with which our discussion is actually concerned; not whether there are, or formerly have been,