Galen of Pergamon (Latín: Claudius Galenus, Greek: Κλαύδιος Γαληνός), born September c. 130 CE, died c. 200), was a Roman and Greek physician, surgeon, and philosopher. Alongside Hippocrates he is the founder of the humoral theory and the Greco-Roman medical system, which remained hegemonic until 17th century in the western world.
