“There’s a story that some incurably melancholic person fell in love with a girl and when the doctors could do nothing to help, love cured him. I think however that he was in love from the start and that he was feeling down and disheartened because of the bad luck he was having with the girl and so seemed to ordinary people to be melancholic. He had no idea at that point that it was love; but when he realized his love for the girl, he stopped feeling down and he got rid of his anger and sorrow and the joy sobered him up out of his sad state. For his mind was restored by doctor love.”

λόγος ὅτι τῶν τοιῶνδέ τις ἀνηκέστως ἔχων, κούρης ἤρα τε καὶ τῶν ἰητρῶν οὐδὲν ὠφελούντων ὁ ἔρως μιν ἰήσατο· δοκέω δὲ ἔγωγε ἐρᾶν μὲν αὐτὸν ἀρχῆθεν, κατηφέα δὲ καὶ δύσθυμον [ἢ] ὑπ' ἀτυχίης τῆς κούρης ἔμμεναι καὶ μελαγχολικὸν δοκέειν τοῖσι δημότῃσιν. οὗτος οὔτε μὴν ἦν ἔρωτα ἐγγιγνώσκων, ἐπεὶ δὲ τὸν ἔρωτα ξυνῆψε τῇ κούρῃ, παύεται τῆς κατηφείης, καὶ διασκίδνησι ὀργήν τε καὶ λύπην, χάρμῃ δὲ ἐξένηψε τῆς δυσθυμίης· καθίσταται γὰρ τὴν γνώμην ἔρωτι ἰητρῷ.

Aretaeus, Causes and Signs of Chronic Diseases 1.5.8, 41,4–11 Hude