Plato, Meno 77d

ἄλλο; πότερον ἡγούμενος τὰ κακὰ ὠφελεῖν ἐκεῖνον ᾧ ἂν γένηται, ἢ γιγνώσκων τὰ κακὰ ὅτι βλάπτει ᾧ ἂν παρῇ; εἰσὶ μὲν οἳ ἡγούμενοι τὰ κακὰ ὠφελεῖν, εἰσὶν δὲ καὶ οἳ γιγνώσκοντες ὅτι βλάπτει. ἦ καὶ δοκοῦσί σοι γιγνώσκειν τὰ κακὰ ὅτι κακά ἐστιν οἱ ἡγούμενοι τὰ κακὰ ὠφελεῖν; οὐ πάνυ μοι δοκεῖ τοῦτό γε. οὐκοῦν δῆλον ὅτι οὗτοι μὲν οὐ τῶν κακῶν ἐπιθυμοῦσιν,

Yes; what else could it be? And does he think the evil benefits him who gets it, or does he know that it harms him who has it? There are some who think the evil is a benefit, and others who know that it does harm. And, in your opinion, do those who think the evil a benefit know that it is evil? I do not think that at all. Obviously those who are ignorant of the evil do not desire it, but only what they supposed