Plato, Meno 95d

ἀλλὰ καὶ Θέογνιν τὸν ποιητὴν οἶσθʼ ὅτι ταὐτὰ ταῦτα λέγει; ἐν ποίοις ἔπεσιν; ἐν τοῖς ἐλεγείοις, οὗ λέγει— καὶ παρὰ τοῖσιν πῖνε καὶ ἔσθιε, καὶ μετὰ τοῖσιν ἵζε, καὶ ἅνδανε τοῖς, ὧν μεγάλη δύναμις. ἐσθλῶν μὲν γὰρ ἄπʼ ἐσθλὰ διδάξεαι· ἢν δὲ κακοῖσιν

are in two minds as to whether virtue is to be taught, but Theognis the poet also says, you remember, the very same thing? In which part of his poems? In those elegiac lines where he says—Eat and drink with these men; sit with them, and be pleasing unto them, who wield great power; for from the good wilt thou win thee lessons in the good; but mingle with the bad,