Tusculan Disputations 5 ¶51 — Cicero (on the Stoics)

Cicero (on the Stoics), Tusculan Disputations 5 ¶51

A mind employed on such subjects, and which night and day contemplates them, contains in itself that precept of the Delphic God, so as to “know itself,” and to perceive its connection with the divine reason, from whence it is filled with an insatiable joy. For reflections on the power and nature of the Gods raise in us a desire of imitating their eternity. Nor does the mind, that sees the necessary dependences and connections that one cause has with another, think it possible that it should be itself confined to the shortness of this life. Those causes, though they proceed from eternity to eternity, are governed by reason and understanding. And he who beholds them and examines them, or rather he whose view takes in all the parts and boundaries of things, with what tranquillity of mind does he look on all human affairs, and on all that is nearer him! Hence proceeds the knowledge of virtue; hence arise the kinds and species of virtues; hence are discovered those things which nature regards as the bounds and extremities of good and evil; by this it is discovered to what all duties ought to be referred, and which is the most eligible manner of life. And when these and similar points have been investigated, the principal consequence which is deduced from them, and that which is our main object in this discussion, is the establishment of the point that virtue is of itself sufficient to a happy life.