The Virtue of Justice

St. Thomas in the Summa Theologiae understands the virtue of justice to be founded upon the notion of jus or right because, according to the classical definition of the virtue, it is by justice that one renders to another his due by a perpetual constant will.( Thomas Aquinas; Summa Theologiae II-II, 58, 1.) Justice directs man in his relations to others according to some kind of equality or rightness.( ST II-II, 57, 1; De Veritate 23, 6.) This relation of rightness is what is meant by jus. It is a right that is due to other men, and it is this object which specifies the virtue. As such, it is logically prior to the virtue itself which perfects a man so as to render this object swiftly, easily and gladly. Hence Thomas treats the question of jus before he does that of justice.