Plato, Meno 99b

δυοῖν ἄρα ὄντοιν ἀγαθοῖν καὶ ὠφελίμοιν τὸ μὲν ἕτερον ἀπολέλυται, καὶ οὐκ ἂν εἴη ἐν πολιτικῇ πράξει ἐπιστήμη ἡγεμών. οὔ μοι δοκεῖ. οὐκ ἄρα σοφίᾳ τινὶ οὐδὲ σοφοὶ ὄντες οἱ τοιοῦτοι ἄνδρες ἡγοῦντο ταῖς πόλεσιν, οἱ ἀμφὶ Θεμιστοκλέα τε καὶ οὓς ἄρτι Ἄνυτος ὅδε ἔλεγεν· διὸ δὴ καὶ οὐχ οἷοί τε ἄλλους ποιεῖν τοιούτους οἷοι αὐτοί εἰσι, ἅτε οὐ διʼ ἐπιστήμην ὄντες τοιοῦτοι. ἔοικεν οὕτως ἔχειν, ὦ Σώκρατες, ὡς λέγεις. οὐκοῦν εἰ μὴ ἐπιστήμῃ, εὐδοξίᾳ δὴ τὸ λοιπὸν

So of two good and useful things one has been rejected: knowledge cannot be our guide in political conduct. I think not. Therefore it was not by any wisdom, nor because they were wise, that the sort of men we spoke of controlled their states—Themistocles and the rest of them, to whom our friend Anytus was referring a moment ago. For this reason it was that they were unable to make others like unto themselves—because their qualities were not an effect of knowledge. The case is probably as you say, Socrates. And if not by knowledge, as the only alternative it must have been by good opinion.