MARCUS AURELIUS was born Marcus Annius Verus in Rome in 121 CE, and assumed the name of Marcus Aurelius Antoninus on his adoption by the emperor Antoninus Pius, whom he succeeded in 161. Following his accession, M. Aurelius conferred half-rule of the empire upon his adoptive younger brother and fellow consul, L. Aurelius Verus, thus establishing the first collegiate principate. M. Aurelius ruled jointly with Verus until the latter's death in 169. M. Aurelius was educated by Marcus Cornelius Fronto, the most acclaimed orator of his day, but abandoned rhetoric for Stoic philosophy. Carrying out the Stoic prin-ciples of moderation and virtuous conduct based on right reason, M. Aurelius ruled with an eye to the good of his subjects. But while justice prevailed at home, the borders of the empire lay under constant siege by barbarian hordes. Therefore, this most pacific and contemplative of emperors was forced to spend much of the latter part of his reign in the field, where he composed his Meditations. Given that he was put under the pressure of incessant warfare, it is easy to see why M. Aurelius should have taken refuge in Stoic philosophy. The Stoics taught that the chief end of man is happiness, and is achieved by living in harmony with nature; the highest good lies in virtue, which is to live in harmony with reason. Part of right reason is knowing how to accept what we cannot change, and to ride out, as it were, the vicissitudes of fortune. It is the mark of a wise man to retain his composure through adversity, regarding it as a thing external and therefore indifferent. Written not as a continuous philosophical tract but as a series of daily thoughts, the Meditations nonetheless are the most important expression of late Stoicism. Simple in style and sincere in tone, they speak eloquently on life, death, and duty; taken together, they faithfully record the mind and character of a man for whom "philosophy" was not merely an academic pursuit of abstract truths but a true design for living. Marcus Aurelius died in his camp on the Danube on March 17, 180, the nineteenth year of his reign.