The highest good of man is consciously to work with God for the common good, and this is the sense in which the Stoic tried to live in accord with nature.

In order to live in accord with nature, it is necessary to know what nature is; and to this end a threefold division of philosophy is made—into Physics, dealing with the universe and its laws, the problems of divine government and teleology; Logic, which trains the mind to discern true from false; and Ethics, which applies the knowledge thus gained