Set yourself free for your own sake; gather and save your time, which till lately has been forced from you, or filched away, or has merely slipped from your hands.

These are the opening lines of the first of the Letters to Lucilius, which go on to argue that time is the one possession we can only waste or keep. Seneca’s longer essay on the subject is On the Shortness of Life. The wording is Richard Gummere’s 1917 Loeb translation, which is in the public domain.