Marcus Aurelius · Meditations VIII.2
Whenever you act, ask: how does this stand with me? Shall I regret it? In a little time I am dead, and all of it is gone.
What this means
Before acting, Marcus runs two quick tests: will I regret this, and does it matter given that I will soon be dead. Death here is not despair but a filter that burns off the trivial. What survives the question is worth doing.
On present, death, duty.