ἔστιν ἄρα ἡ ἀρετὴ ἕξις προαιρετική, ἐν μεσότητι οὖσα τῇ πρὸς ἡμᾶς, ὡρισμένῃ λόγῳ καὶ ᾧ ἂν ὁ φρόνιμος ὁρίσειεν. μεσότης δὲ δύο κακιῶν, τῆς μὲν καθ᾽ ὑπερβολὴν τῆς δὲ κατ᾽ ἔλλειψιν:
Virtue then is a settled disposition of the mind as regards the choice of actions and feelings, consisting essentially in the observance of the mean relative to us, this being determined by principle, that is, as the prudent man would determine it. And it is a mean state between two vices, one of excess and one of defect.
Aristotle, Nicomachean Ethics, Book II, translated by Harris Rackham. The illustration of the philosopher is a line engraving by P. Fidanza after Raphael Sanzio.