Cicero wrote On Obligations (De Officiis) in late 44 BC after the assassination of Julius Caesar to provide principles of behavior for aspiring politicians. It has subsequently played a seminal role in the formation of ethical values in western Christendom. Adopted by the fourth-century Christian humanists, it became transmuted into the moral code of the high Middle Ages. Thereafter, in the Renaissance from the time of Petrarch, and in the Age of...