These disputed questions are the work of a theologian for whom philosophy was the necessary prerequisite of his discipline. Thomas discusses virtue with reference to the definitions of St. Augustine and Aristotle and develops a distinction between the acquired virtues and the virtues which are infused into the soul by grace. The subtle interactions of the natural and supernatural have never been discussed with more clarity. Justice, prudence, courage, and temperance - the cardinal virtues - are shown to have both acquired and infused instances.
