ABSTRACT
In the Middle Ages Thomas Aquinas much developed two aspects of Aristotle’s theory of the virtues. There is much more of a stress on the habitual character of virtue. The notion of practical wisdom or phronesis is sharpened to precision in the technical study of prudence. In the course of this development we are provided with a quite practical guide to the acquisition and use of virtue which is surprisingly modern. There is in the Summa Theologiae an extended section on habits and virtues sometimes referred to as a treatise on this subject.
