It is more convenient, for the purpose of expounding the morality of common sense, to understand by Virtue a quality exhibited in right conduct; for then we can use the common notions of the particular virtues as heads for the classification of the most important kinds or aspects of right conduct as generally recognised. And I think that this employment of the term is as much in accordance with ordinary usage as any other equally precise use would be.
ME Book 3 Chapter 2 Section 1