That Marcus Aurelius is remembered several millennia after his death is primarily due to a diary that he kept during his lifetime which he referred to by the utilitarian title “Notes to Himself.” Over time those notes in a personal diary became one of the foundational references works for the ancient Greek philosophy known as Stoicism. The best research available indicates that the diary—which came to be known simply as Meditations—was started late in the life of Aurelius. That his own reference point should be to humbly titled and to the point is indicative of the content and the philosophy it expresses, which is essentially one of resigned acceptance to whatever life throws at you based upon a solid commitment to making the best of it rather than wallowing in self-pity at becoming a plaything of fate.
The essential underlying feature of Meditations is that one cannot control the corruption of the body, but one can built a temple to the divine spirit of the mind. That lofty goal translates into the concrete example of living by a code of ethics mandated by starkly drawn principles of what is right and what is wrong.
Even the structure of the Meditations reflects the Stoic mentality of its writer. Lacking organization and with no apparent connection between external events and the urge to record thoughts in his diary, it is a philosophical work that appears to accept inspiration and it comes rather than forcing it through attempts at imposing control. The writing of Marcus Aurelius reflects a life lived that sought to find harmony with the universe around him by stepping into the rhythm that fate provided rather than trying to syncopate it from without.
Though recorded by in diary form by Aurelius sometime around A.D. 170, the Meditations as a philosophical document would not be published until 1558.