Galen's monumental work reconciling Hippocratic medicine with Platonic philosophy. Across nine books, he demonstrates that the doctrines of the two great authorities are fundamentally compatible — particularly regarding the tripartite division of the soul and its physiological basis.
Start ReadingGalen establishes his project of reconciling Hippocrates and Plato, arguing that both recognised the tripartite nature of the soul.
The seat of the ruling part of the soul. Galen argues against the Stoics that reason resides in the brain, not the heart, supporting Plato and Hippocrates.
Anatomical proof that the brain governs sensation and voluntary motion. Galen presents his experimental evidence from nerve-cutting demonstrations.
The spirited part of the soul and the heart. Galen examines the role of the heart as the seat of θυμός (spiritedness), aligning Plato's Republic with anatomical observation.
The voice and its organs. Galen examines the anatomy of the larynx and the mechanism of voice production, connecting it to his broader psychophysiology.
The appetitive soul and the liver. Galen examines the liver as the seat of desire and nutrition, completing the anatomical mapping of Plato's three-part soul.
Hippocratic and Platonic therapy of the passions. Galen examines how the rational soul can moderate anger and desire through philosophical training.
The unity of the Hippocratic-Platonic tradition. Galen argues that the ethical and physiological doctrines of both authorities form a coherent system.
Conclusion and defence. Galen summarises his arguments for the compatibility of Hippocrates and Plato, and responds to potential objections.