Written in 44 B.C. by Roman official, orator, and philosopher, Marcus Tullius Cicero, On Duties is a philosophical treatise on moral duty, or 'appropriateaction. 'It is written as a three-section letter, in lieu of a visit, to his son, Marcus Tullius Cicero Minor, who lived in Athens at the time, and was studying philosophy. Cicero wrote the letter in less than a month during the last year of his life.

This text was written during a time of great political upheaval in Rome, just after Caesar's assassination, while the Roman Republic lay in jeopardy. Born into a high social class, Cicero had studied under various scholars and made his way up the cursushonorum, the sequential order of Roman public offices, to consulship, the highest-ranking elected office in the Roman Senate. During his year as consul, in 63 BC, Cicero ordered the execution, without trial, of members of an attempted coup, and was subsequently exiled for this action. He had alsobeen offered to join Julius Caesar's First Triumvirate, which he refused. When he returned to Rome from his exile, Cicero struggled to find a place for himself in politics, and instead devoted his attention to philosophical writings.

In On Duties, Cicero frames his examination of morally correct action for humans in terms of what is honorable (for the public good/virtues of human life) and what is useful (for the private good/necessities of human life). For Cicero, appropriate action exists on a five fold spectrum: between honorable and disgraceful; between two honorable actions; between useful and useless;between two useful actions; and, finally, between what is honorable and useful.

In the first book, he defines the idea of honorableness. For Cicero, the word is interchangeable with 'virtue.' Human virtue consists of four things: wisdom, justice, greatness of spirit, and moderation. In Book II, Cicero defines utility and issues advice on how to manage utility in the face of selfishness. In Book III, he attempts to investigate whether and how actions create a conflict between the honorable and the useful. To do this, he provides many anecdotal examples from literature, history, philosophy, and contemporary political situations.

The entire treatise is a meditation on the First Triumvirate's seizure of power in Rome, and its subsequent fallout. It can't be read without acknowledging both Cicero's unique position within Roman society at the time of its writing, nor the political situation in Rome. Cicero strongly supported the Roman Senate and rejected Caesar's dictatorship. He perceived the First Triumvirate as putting their self-interests above the interests of the common good, which Cicero believed should not be the function of government. This tension resonates throughout On Duties, as Cicero attempts to reconcile one's duty to oneself and one's fellow citizens, homeland, family, and faith.