Plato, Meno 93d

τὴν ἀρετὴν ἣν αὐτὸς ἀγαθὸς ἦν; ἢ οὐκ ἀκήκοας ὅτι Θεμιστοκλῆς Κλεόφαντον τὸν ὑὸν ἱππέα μὲν ἐδιδάξατο ἀγαθόν; ἐπέμενεν γοῦν ἐπὶ τῶν ἵππων ὀρθὸς ἑστηκώς, καὶ ἠκόντιζεν ἀπὸ τῶν ἵππων ὀρθός, καὶ ἄλλα πολλὰ καὶ θαυμαστὰ ἠργάζετο ἃ ἐκεῖνος αὐτὸν ἐπαιδεύσατο καὶ ἐποίησε σοφόν, ὅσα διδασκάλων ἀγαθῶν εἴχετο· ἢ ταῦτα οὐκ ἀκήκοας τῶν πρεσβυτέρων; ἀκήκοα. οὐκ ἂν ἄρα τήν γε φύσιν τοῦ ὑέος αὐτοῦ ᾐτιάσατʼ ἄν τις εἶναι κακήν.

of his own goodness to him? Have you never heard how Themistocles had his son Cleophantus taught to be a good horseman? Why, he could keep his balance standing upright on horseback, and hurl the javelin while so standing, and perform many other wonderful feats in which his father had had him trained, so as to make him skilled in all that could be learnt from good masters. Surely you must have heard all this from your elders? I have. Then there could be no complaints of badness in his son’s nature?