Notes from Wikiquote
μοι νυνὶ γέγονεν ἐκ τοῦ διαλόγου μηδὲν εἰδέναι· ὁπότε γὰρ τὸ δίκαιον μὴ οἶδα ὅ ἐστιν, σχολῇ εἴσομαι εἴτε ἀρετή τις οὖσα τυγχάνει εἴτε καὶ οὔ, καὶ πότερον ὁ ἔχων αὐτὸ οὐκ εὐδαίμων ἐστὶν ἢ εὐδαίμων. | Hence the result of the discussion, as far as I'm concerned, is that I know nothing, for when I don't know what justice is, I'll hardly know whether it is a kind of virtue or not, or whether a person who has it is happy or unhappy. | Republic, 354b-c (conclusion of book I), as translated by M.A. Grube in Republic (Grube Edition) (1992) revised by C.D.C. Reeve, p. 31 | Confer Apology 21d (see above), Theaetetus 161b (see above) and Meno 80d1-3: "So now I do not know what virtue is; perhaps you knew before you contacted me, but now you are certainly like one who does not know." | Confer Cicero, Academica, Book I, section 1: "ipse se nihil scire id unum sciat ("He himself thinks he knows one thing, that he knows nothing"). Often quoted as "scio me nihil scire" or "scio me nescire." A variant is found in von Kues, De visione Dei, XIII, 146 (Werke, Walter de Gruyter, 1967, p. 312): "...et hoc scio solum, quia scio me nescire... [I know alone, that (or because) I know, that I do not know]." In the modern era, the Latin quote was back-translated to Greek as "ἓν οἶδα ὅτι οὐδὲν οἶδα", hèn oîda hóti oudèn oîda). | Confer Diogenes Laertius, II.32 (see above)