Plato, Laws 663d

ἀναγκαῖόν που τὴν τῆς ἀμείνονος. ἀναγκαῖον ἄρα τὸν ἄδικον βίον οὐ μόνον αἰσχίω καὶ μοχθηρότερον, ἀλλὰ καὶ ἀηδέστερον τῇ ἀληθείᾳ τοῦ δικαίου τε εἶναι καὶ ὁσίου βίου. κινδυνεύει κατά γε τὸν νῦν λόγον, ὦ φίλοι. νομοθέτης δὲ οὗ τι καὶ σμικρὸν ὄφελος, εἰ καὶ μὴ τοῦτο ἦν οὕτως ἔχον, ὡς καὶ νῦν αὐτὸ ᾕρηχʼ ὁ λόγος ἔχειν, εἴπερ τι καὶ ἄλλο ἐτόλμησεν ἂν ἐπʼ ἀγαθῷ ψεύδεσθαι πρὸς τοὺς νέους, ἔστιν ὅτι τούτου ψεῦδος λυσιτελέστερον ἂν

Undoubtedly, then, the unjust life is not only more base and ignoble, but also in very truth more unpleasant, than the just and holy life. It would seem so, my friends, from our present argument. And even if the state of the case were different from what it has now been proved to be by our argument, could a lawgiver who was worth his salt find any more useful fiction than this (if he dared to use any fiction at all in addressing the youths for their good), or one more effective in persuading all men to act justly in all things