Plato, Laws 858d

ποιητῶν καὶ ὅσοι ἄνευ μέτρων καὶ μετὰ μέτρων τὴν αὑτῶν εἰς μνήμην συμβουλὴν περὶ βίου κατέθεντο συγγράψαντες, προσέχωμεν τὸν νοῦν, τοῖς δὲ τῶν νομοθετῶν μὴ προσέχωμεν; ἢ πάντων μάλιστα; πολύ γε. ἀλλὰ δῆτα οὐ χρὴ τὸν νομοθέτην μόνον τῶν γραφόντων περὶ καλῶν καὶ ἀγαθῶν καὶ δικαίων συμβουλεύειν, διδάσκοντα οἷά τέ ἐστι καὶ ὡς ἐπιτηδευτέον αὐτὰ τοῖς μέλλουσιν εὐδαίμοσιν ἔσεσθαι; καὶ πῶς οὔ;

poets, and all who, either with or without meter, have composed and put on record their counsels concerning life,—but to pay no attention to those of the lawgivers? Or should we not attend to them above all others? Yes, far above all. But we surely do not mean that the lawgiver alone of all the writers is not to give counsel about what is noble, good and just, teaching what these are, and how those who intend to be happy must practice them. Of course he must do so.