Plutarch

Plutarch (c. 46 – c. 119 CE) was a Greek philosopher, biographer, and priest born at Chaeronea in Boeotia, where he ran a small philosophical school and served for some twenty years as a priest of Apollo at Delphi. A Middle Platonist who had studied under the Platonist Ammonius at Athens, he held local office, traveled to Rome, and produced an enormous body of work: the paired Parallel Lives of famous Greeks and Romans, and the Moralia, a wide-ranging collection of dialogues, essays, and treatises on ethics, religion, psychology, and natural philosophy.

For the mind-power lineage, Plutarch is significant as a transmitter and developer of Platonic religious philosophy in a popular, humane, and psychologically acute register. He elaborated a rich doctrine of daimones—intermediary spirits between gods and humans who guide, warn, and influence souls—taking up the Socratic daimonion and the layered cosmos of Platonism and giving it vivid moral and devotional form.

His essays on the cure of the soul, the control of anger, the management of desire, and the soul’s progress in virtue amount to a practical moral psychology aimed at the inner ordering of the self. And his Delphic dialogues probe the nature of the divine, the soul, and providence.

Through his immense later readership, Plutarch carried the conviction of an ensouled, layered cosmos and the primacy of inner moral cultivation forward into the Renaissance and, through the essay tradition, to figures like Emerson.