Aristotle, Eudemian Ethics, Book 2 81:

ἀναγκαῖον ἂν εἰή τὴν ἠθικὴν ἀρετὴν καθ αὑτὸν ἕκαστον μεσότητα εἶναι καὶ περὶ μές ἄττα ἐν ἡδοναῖς καὶ λύπαις καὶ ἡδέσι καὶ λυπηροῖς.? ἔσται δ ἡ μεσότης ὁτὲ μὲν ἐν ἡδοναῖς καὶ γὰρ ὑπερβολὴ καὶ ἔλλειψις, ὁτὲ δ ἐν λύπαις, ὁτὲ δ ἐν ἀμφοτέραις. ὁ γὰρ ὑπερβάλλων τῷ χαίρειν τῷ ἡδεῖ ὑπερβάλλει καὶ ὁ τῷ λυπεῖσθαι τῷ ἐναντίῳ, καὶ ταῦτα ἢ ἁπλῶς ἢ πρός τινα ὁρ´ον, οἱο῀ν ὅταν μὴ ὡς οἱ πολλοί:?