Seneca (c. 4 BC – AD 65)
What man can you show me who places any value on his time, who reckons the worth of each day, who understands that he is dying daily? For we are mistaken when we look forward to death; the major portion of death has already passed. Whatever years lie behind us are in death’s hands.
Therefore… hold every hour in your grasp. Lay hold of to-day’s task, and you will not need to depend so much upon tomorrow’s. While we are postponing, life speeds by. Nothing… is ours, except time. We were entrusted by nature with the ownership of this single thing, so fleeting and slippery that anyone who will can oust us from possession.