Today is the birthday of Marcus Aurelius. This Roman emperor (born 121 C.E.) was also a philosopher of Stoicism.
This ancient and largely naturalistic philosophy sought serenity within the world of action by concerning oneself only with what was within one’s control: one’s choices.
The emperor Marcus Aurelius kept a personal journal of reflections while on his military campaigns, and this was published after his death as The Meditations. It remains a classic today, and paints a poignant picture of a man wrestling with his own emotions and duties.