Plato, Meno 100a

παραγίγνηται, εἰ μή τις εἴη τοιοῦτος τῶν πολιτικῶν ἀνδρῶν οἷος καὶ ἄλλον ποιῆσαι πολιτικόν. εἰ δὲ εἴη, σχεδὸν ἄν τι οὗτος λέγοιτο τοιοῦτος ἐν τοῖς ζῶσιν οἷον ἔφη Ὅμηρος ἐν τοῖς τεθνεῶσιν τὸν Τειρεσίαν εἶναι, λέγων περὶ αὐτοῦ, ὅτι οἶος πέπνυται τῶν ἐν Ἅιδου, τοὶ δὲ σκιαὶ ἀίσσουσι. ταὐτὸν ἂν καὶ ἐνθάδε ὁ τοιοῦτος ὥσπερ παρὰ σκιὰς ἀληθὲς ἂν πρᾶγμα εἴη πρὸς ἀρετήν.

unless there should be somebody among the statesmen capable of making a statesman of another. And if there should be any such, he might fairly be said to be among the living what Homer says Teiresias was among the dead—He alone has comprehension; the rest are flitting shades. In the same way he on earth, in respect of virtue, will be a real substance among shadows.