A treatise on the natural faculties of the body — attraction, retention, and expulsion. Galen defends Hippocratic medicine against rival schools and establishes principles that dominated medicine for fifteen centuries.
Start ReadingGalen examines the natural faculties — attraction, retention, alteration, and expulsion — that govern the body's basic physiological processes.
The faculty of alteration. Galen examines how the body transforms food into blood, flesh, and other substances through its natural powers.
The faculty of expulsion. Galen examines how the body eliminates waste products, defending the existence of natural faculties against Erasistratean mechanistic explanations.