Plato, Parmenides, Philebus, Symposium, Phaedrus, Φαῖδρος 273:

καὶ ἐπιστάμενοσ αὐτὰ ἀξιῶ ἰατρικὸσ εἶναι καὶ ἄλλον ποιεῖν ᾧ ἂν τὴν τούτων ἐπιστήμην παραδῶ," τί ἂν οἰεί ἀκούσαντασ εἰπεῖν; τί δ’ ἄλλο γε ἢ ἐρέσθαι εἰ προσεπίσταται καὶ οὕστινασ δεῖ καὶ ὁπότε ἕκαστα τούτων ποιεῖν, καὶ μέχρι ὁπόσου; εἰ οὖν εἴποι ὅτι "οὐδαμῶσ· ἀλλ’ ἀξιῶ τὸν ταῦτα παρ’ ἐμοῦ μαθόντα αὐτὸν οἱο͂́ν τ’ εἶναι ποιεῖν ἃ ἐρωτᾷσ;