Marcus Aurelius ruled as Roman emperor from 161–180 CE, the years in which he wrote the Meditations. Not only was he heavily occupied with running the administrative and judicial affairs of a vast empire, he was also waging campaigns against barbaric incursions at the time Meditations was written. Never one to live in luxury back in Rome while his generals endured the hardships of war, Aurelius led the troops himself. Otherwise, he would not have been able to maintain their loyalty. However, having to endure long periods of time away from home meant that Aurelius did not have access to the stimulating philosophical discussions he was accustomed to. It is unlikely that anyone in the Roman military with whom he had daily contact in the field had the time, energy, or inclination toward the finer points of introspection. The Meditations allowed him to continue these discussions as he reflected on his life and beliefs.
Quintus Junius Rusticus
Rusticus evidently had a long-term influence on the formation of Aurelius as a philosopher king, and it can be said that his teachings underpin Meditations. Rusticus made his extensive library available to his student, particularly the words of the Stoic Epictitus. A bust of Rusticus was included in Aurelius's pater familias home shrine. Meditations may be thought of as a "portable" shrine.
Born a slave, Epictetus was unorthodox as a Stoic, in that he believed in greater individual freedom of will rather than Fate. Aurelius encountered the philosophy of Epictetus through his mentor, Rusticus, who may have studied directly under Epictetus. Epictetus lived his beliefs with faithful determination despite adverse conditions—he was lame but lived a sparse life, lecturing on city streets. He is recorded as having said, "You are a little soul bearing up a corpse" (Book 4).
Hadrian was careful to send to Aurelius's household tutors at the peak of philosophical expertise. Aurelius uses the rule of Hadrian, one of the "good" Roman emperors, as a reminder to himself that even the most respected and honored emperor does not rule forever.
Epicureans held that all creation is random and therefore not subject to any organization by Providence. Aurelius examines this philosophy most prominently in terms of living in the present moment without past regrets or future fears. Containing the seeds of modern-day physics, the approach of Epicurus is offset throughout most of Meditations by its opposition to a systematic universe as described by the Stoics.
Heraclitus was particularly noted for his very short and perplexing statements that had his students scratching their heads in an attempt to understand them. He asserted that reason is the ultimate power of the cosmos and the interchanges of the four elements.
Probably the most famous philosopher of the ancient world, Socrates had been a teacher of Plato, but did not produce any written material. Therefore, this line of Greek philosophy is really a combination of both Socrates and Plato, who recorded his teacher's life, teachings, and death. The unique method of question-and-answer following the principles of logic is now known as the Socratic Method.