Meditations by Marcus Aurelius (180)

In a campaign tent on the Danube frontier, the ruler of the known world wrote himself reminders he never meant another soul to read. Marcus Aurelius could command legions, raise temples, and end a life with a word, and the only thing he could not trust was his own character under the weight of all that power. So he kept a private notebook, in Greek, and filled it with corrections: rise though the bed is warm, do not rage at fools, remember that the man who wronged you this morning is your kinsman, remember above all that you will die and soon. There is no audience here, no pose, only an emperor talking himself back toward decency one entry at a time. That is what makes it beautiful and almost unbearable at once. Two thousand years later you are reading a powerful man's quarrel with himself, and the wisest book ever written about how to live turns out to be the one its author never meant for you to see.