In the first book he divides duties into “ordinary,” or the way of the commandments, binding upon all alike; and “perfect,” which consist in following the counsels. After treating then of some elementary duties, such as those towards parents and elders, he touches upon the two principles which lead the mind, reason and appetite, and shows that what is becoming consists in thinking of good and right things, and in the subjection of the appetite to reason, I. 24, § 106. and supplies certain rules and examples, ending with a discussion on the four Cardinal Virtues, Prudence, Justice, Fortitude, and Temperance.