Diatribe and Plutarch's practical ethics

This dissertation examines five practical ethical works by Plutarch of Chaeronea (c. 50 CE–c.120 CE): On Talkativeness, On Curiosity, On Avoiding Borrowing Money, On Excessive Modesty, and On Superstition. In each work Plutarch explains the problems associated with the vice in the title and proposes a self-training regimen for overcoming the vicious behavior. Plutarch’s diagnoses of and cures for these vicious behaviors are based on his belief (following Plato and Aristotle) that the human soul has a rational part and irrational part that work in opposition to each other. Vicious behavior arises when the rational part loses control of the irrational. Plutarch’s regimens are designed to put the rational part of the soul back in control to restore virtue. I argue that Plutarch gives an abstract account of the process of putting reason in control of the soul in his treatise On Moral Virtue, and that the five practical ethical works show that abstract process in specific cases. I argue that On Moral Virtue links Plutarch’s practical and theoretical philosophy: the ordering of one’s soul under the control of reason mirrors the creator god’s ordering of the cosmos. I also argue that On Moral Virtue and the five practical ethical works are linked by Plutarch’s use of the diatribe, a rhetorical style associated with the Cynic and Stoic philosophical schools. Plutarch’s innovation is to appropriate this style from rival philosophical schools and use it to argue for Platonic ethics. I argue he does this to promote Platonism to a wider audience.