The "Meditations" of Marcus Aurelius is seen as one of the three most important expressions of Stoicism. Pierre Hadot here uncovers levels of meaning and expands the understanding of its underlying philosophy through what he argues are the deceptive clarity and ease of the work's style. Written by the Roman Emperor for his own private guidance and self-admonition, the "Meditations" set forth principles for living a good and just life. Hadot probes Marcus Aurelius's guidelines and convictions and discerns the conceptual system that grounds them. Quoting the "Meditations" to illustrate his analysis, Hadot unfolds the philosophical context of the "Meditations", commenting on the philosophers Marcus Aurelius read and giving special attention to the teachings of Epictetus, whose disciple he was. The soul, the guiding principle within us, is in Marcus Aurelius's Stoic philosophy an invoilable stronghold of freedom, the "inner citadel". This study offers a picture of the philosopher-emperor, a fuller understanding of the tradition and doctrines of Stoicism, and insight on the culture of the Roman Empire in the 2nd century.