Symposium 204a
“Nor moreover do the unlearned love wisdom or desire to become wise, and this is is exactly why ignorance is such a bad thing: a man who is not noble, good, or sensible will be satisfied with himself as he is. When someone is unconscious of the fact that he lacks a particular thing, he naturally does not desire it.”
οὐδ᾽ αὖ οἱ ἀμαθεῖς φιλοσοφοῦσιν οὐδ᾽ ἐπιθυμοῦσι σοφοὶ γενέσθαι: αὐτὸ γὰρ τοῦτό ἐστι χαλεπὸν ἀμαθία, τὸ μὴ ὄντα καλὸν κἀγαθὸν μηδὲ φρόνιμον δοκεῖν αὑτῷ εἶναι ἱκανόν. οὔκουν ἐπιθυμεῖ ὁ μὴ οἰόμενος ἐνδεὴς εἶναι οὗ ἂν μὴ οἴηται ἐπιδεῖσθαι.
Ion of Chios, fr. 55
“Know yourself” is not a hard command:
but of all the gods only Zeus can do it.
τὸ γνῶθι σαυτὸν τοῦτ’ ἔπος μὲν οὐ μέγα,
ἔργον δ’ ὅσον Ζεὺς μόνος ἐπίσταται θεῶν