The full definition, "Virtue is a good quality of the mind by which one lives correctly, which no one uses wrongly, and which God produces in us without us," is the common medieval definition of virtue. (Cf. S.T., I-II, 55, 4, obj. 1). Lottin traces some of the history of this definition in RSPT, XVIII (1929), 371-72. Peter of Poitiers seems to have been the first to use the definition in exactly its present form.
St. Augustine, Contra Julianum, IV, 3 (PL 44:745).
Glossa interlinearis, super Matt. 1:2 (V:5r).
E.g., Hugh of St. Victor, De sacramentis, I, 10, 2 (PL 176:327); Alexander of Hales, Summa Theol., III, n. 678 (QR IV:1076); St. Albert the Great, In Sent., III, d. 23, a. 18 (BO 28:437-38).
In q. 14, a. 1.
Aristotle, Metaph., {B}, 2 (996b 13); cf. ibid., B, 4 (999b 21, 1001a 27).
See above, at the beginning of this article.
St. John Damascene, De fide orthodoxa, IV, 10 (PG 94:1127).
Ibid.
St. Augustine, In Joann., super 8:33, XL (PL 35:1690); ibid., super 14:29, LXXIX (PL 35:1837); Quaest. evang., super Luc. 17:5, II (PL 35:1352).
St. John Damascene, De fide orthodoxa, IV, 11 (PG 94:1127).
Hugh of St. Victor, De verbo incarnato, princ. (PL 177:295). Cf. Summa sententiarum, I, 1 (PL 176:43).
Pseudo-Dionysius, De divinis nominibus, VII (PG 3:871).
St. Augustine, Confessiones, III, 6 (PL 32:687); V, 4 (PL 32:708).
Aristotle, De anima, III, 10 (433b 27); 11 (434a 16).
In q. 14, aa. 4, 9.
St. Gregory, In evang., II, 26 (PL 76:1202).
St. Augustine, Epist. CXLVII, ad Paulinam, 2 (PL 33:599); 3 (PL 33:600).
Ibid.