Plato, Laws 688e

ἄριστʼ, ὦ Κλεινία, καὶ ποιῶμεν ἃ λέγεις. ἔσται ταῦτα, ἐὰν θεὸς ἐθέλῃ. λέγε μόνον. φαμὲν δή νυν, καθʼ ὁδὸν ἰόντες τὴν λοιπὴν τοῦ λόγου, τὴν μεγίστην ἀμαθίαν τότε ἐκείνην τὴν δύναμιν ἀπολέσαι καὶ νῦν ταὐτὸν τοῦτο πεφυκέναι ποιεῖν, ὥστε τόν γε νομοθέτην, εἰ τοῦθʼ οὕτως ἔχει, πειρατέον ταῖς πόλεσιν φρόνησιν μὲν ὅσην δυνατὸν ἐμποιεῖν, τὴν δʼ ἄνοιαν ὅτι μάλιστα ἐξαιρεῖν. δῆλον.

It shall be so, God willing. Only say on. Well then, to advance further on the track of our discourse,—we assert that it was ignorance, in its greatest form, which at that time destroyed the power we have described, and which naturally produces still the same results; and if this is so, it follows that the lawgiver must try to implant in States as much wisdom as possible, and to root out folly to the utmost of his power. Obviously.