On the Virtues: Part One of on the Virtues and Vices

In William's terminology, humans are born with natural virtues, persons can increase virtue by making it habitual (consuetudinal virtues), and some virtues come only by God's grace (gratuitous virtues). The interaction between the Aristotelian and Augustinian accounts of virtue is a major complementary theme of this work.

This book offers valuable insights into mediaeval thought on the virtues.