Plato, Laws 682a

λέγει γὰρ δὴ ταῦτα τὰ ἔπη καὶ ἐκεῖνα, ἃ περὶ τῶν Κυκλώπων εἴρηκεν, κατὰ θεόν πως εἰρημένα καὶ κατὰ φύσιν· θεῖον γὰρ οὖν δὴ καὶ τὸ ποιητικὸν ἐνθεαστικὸν ὂν γένος ὑμνῳδοῦν, πολλῶν τῶν κατʼ ἀλήθειαν γιγνομένων σύν τισιν Χάρισιν καὶ Μούσαις ἐφάπτεται ἑκάστοτε. καὶ μάλα. εἰς δὴ τὸ πρόσθεν προέλθωμεν ἔτι τοῦ νῦν ἐπελθόντος ἡμῖν μύθου· τάχα γὰρ ἂν σημήνειέ τι τῆς ἡμετέρας περὶ βουλήσεως. οὐκοῦν χρή;

Indeed, these verses of his, as well as those he utters concerning the Cyclopes, are in a kind of unison with the voices of both God and Nature. For being divinely inspired in its chanting, the poetic tribe, with the aid of Graces and Muses, often grasps the truth of history. It certainly does. Now let us advance still further in the tale that now engages us; for possibly it may furnish some hint regarding the matter we have in view. Ought we not to do so?