In the 3rd century BCE, Hippocrates introduced his theory of Humoralism. It was based on the notion that 4 fluids, each corresponding to one of the 4 elements, permeate the human body and cause disease when not in balance. Theories regarding the 4 humors—blood, black bile, yellow bile, and phlegm—expanded over the years, and in the 2nd century CE, Galen published a treatise which associated a specific temperament with each humor. What humor was thought to cause a melancholic disposition? Discuss