On the Natural Faculties

The Galenic corpus is the collection of writings of the ancient physician Galen. Galen's understanding of anatomy and medicine was principally influenced by the then-current theory of humorism, as advanced by many ancient Greek physicians such as Hippocrates. His theories dominated and influenced Western medical science for nearly two millennia. His anatomical reports, based mainly on dissection of monkeys, especially the Barbary Macaque, and pigs, remained uncontested until 1543, when printed descriptions and illustrations of human dissections were published in the seminal work De humani corporis fabrica by Andreas Vesalius where Galen's physiological theory was accommodated to these new observations.