Ruler of a vast empire, Marcus wrote the Meditations as notes to himself in the margins of military campaigns and court politics. The book was never meant to be read. What survives is the most honest record of how a serious person tries to apply Stoicism to the weight of an actual life.
Its themes are few and repeated: accept what is not in your power; act from virtue; keep death in view; be good now because there is no other time. The book has survived two millennia because these remain the only things that matter.