Marcus Aureliusthe emperor at his desk

He was drafted into the imperial succession as a boy and spent nineteen years as emperor, most of them on the Danube frontier or managing a plague that ran through the empire for a decade. He had studied philosophy since his teens, and by its own account wanting the job would have been the first thing wrong with him.

The Meditations were written in Greek, in camp, in the last years of his life, and addressed entirely to himself. There is no argument in them, no system, and no reader in mind. It is a man talking himself into getting up in the morning, into tolerating colleagues he finds tedious, and into remembering that he is going to die — the same few instructions, written out again and again over years, because they kept not sticking.

That is exactly why it lasted. It is the only major work of ancient philosophy by someone holding absolute power, and it spends its length on how not to be ruined by holding it. His son Commodus succeeded him and went the other way entirely, which is either the strongest argument against the book or the strongest one for it.

“The happiness of your life depends upon the quality of your thoughts.”

Marcus Aurelius