Note 5 — Chapter XXII · MENON.
Reading edition
Plato, Menon, p. 72 A. καθ’ ἑκάστην γὰρ τῶν πράξεων καὶ τῶν ἡλικῶν πρὸς ἕκαστον ἔργον ἑκάστῳ ἡμῶν ἡ ἀρετή ἐστιν. ὡσαύτως δὲ καὶ ἡ κακία.
Though Sokrates disapproves this method of answering — τὸ ἐξαριθμεῖν τὰς ἀρετάς (to use the expression of Aristotle) — yet Aristotle seems to think it better than searching for one general definition. See Politica, i. 13, p. 1260, a. 15-30, where he has the Platonic Menon in his mind.