Mortality
Aurelius devotes the main focus of his journal to the contemplation of mortality, specifically as it manifests its existence through time. He observes his own mortality in the diverse experiences of time. Primarily an observer, Aurelius prefers to consider life a temporary stage, after which the gods assign the human a new fate. As his own death approaches, even through the context of the journal, Aurelius begins to grow more deliberate about his proclamations of self. He is making peace with the contents of his life and taking a final stance about belief.
Duty
As a believer, Aurelius is continually concerned with the idea of duty. He believes his is, naturally to the gods, but also to his own mind. He looks inward to solve problems and to ponder the nature of existence. Unlike the people around him, Aurelius finds duty to himself the primary one. Colored by his devotion to the gods, he interprets every man's life as a specific endeavor. He often comments upon his own inability to live up to his duty, though he abstains from many pleasures along the way.
Identity
Coupled with his rigorous, duty-bound conscience, Aurelius struggles to find peace in his identity. As the emperor, he is a notable man who has achieved much through power and honor. He receives homage from his subjects and approval among his mentors. Nevertheless, Aurelius is a deep thinker. He must find an internal satisfaction that he has honored himself. This is a challenge for anyone, but it is especially difficult for Aurelius because he chooses not to accept the voices of those around him, looking entirely for his own approval and that of the gods, as he perceives them.