Discourses: Book 2 14 : 2
So also in our own case, we picture the work of the philosopher to be something like this: He should bring his own will into harmony with what happens, so that neither anything that happens happens against our will, nor anything that fails to happen fails to happen when we wish it to happen. The result of this for those who have so ordered the work of philosophy is that in desire they are not disappointed, and in aversion they do not fall into what they would avoid; that each person passes his life to himself, free from pain, fear, and perturbation, at the same time maintaining with his associates both the natural and the acquired relationships, those namely of son, father, brother, citizen, wife, neighbour, fellow-traveller, ruler, and subject.