Four Humors Theory

An ancient and outdated medicine theory that states that a being's health is maintained through a balance of four bodily fluids, and an imbalance of such cause diseases. This theory heavily implies that such fluids regulate personalities, and is the basis of the four temperaments (Choleric, Melancholic, Phlegmatic, Sanguine). The four bodily fluids are composed of: - Blood, which causes sociable, extroverted, and comedic personality. See Sanguine - Phlegm (Pus, Mucus, Saliva, Sweat), which causes reserved and introverted personality. See Phlegmatic - Black Bile (Spleen, Cancer), which causes sad and depressed personality. See Melancholic - Yellow Bile (Gallbladder, Vomit, Feces), which causes short-tempered, ambitious, and aggressive personality. See Choleric Therefore, to combat diseases, one must get rid of excess humor, such as bloodletting. Temperature and humidity of the body such as Hot, Cold, Dry, and Wet are implied to be the balancing of humors. Hence, some might believe that this theory is the earliest attempt to understand Homeostasis, the regulation of biological mechanism. Originating from Ancient Greek thinkers and possibly spread as far into China, this theory persisted well into the 19th Century, in which Germ Theory becomes the foundation of modern medicine and discarded this 2300-years old theory.