De Officiis (On Duties, On Obligations, or On Moral Responsibilities) is a 44 BC treatise by Marcus Tullius Cicero divided into three books, in which Cicero expounds his conception of the best way to live, behave, and observe moral obligations. The posthumously published work discusses what is honorable (Book I), what is to one's advantage (Book II), and what to do when the honorable and private gain apparently conflict (Book III). For the first two books Cicero was dependent on the Stoic philosopher Panaetius, but wrote more independently for the third book.
