The term "humors" originates from ancient medical theories that believed the human body was governed by four fundamental bodily fluids or "humors": blood, phlegm, yellow bile, and black bile. These humors were thought to influence a person's temperament, health, and personality.
In ancient Greece, particularly through the teachings of Hippocrates (circa 460–370 BC), it was believed that an imbalance among these humors caused diseases and affected mental states. This concept was later adopted and expanded upon by Roman physicians, notably Galen, who emphasized the importance of balancing these fluids for both physical and mental well-being.
The word "humor" comes from the Latin word "humor," meaning "liquid" or "fluid." Over time, it came to refer specifically to these bodily fluids believed to influence health and temperament. The idea was that different combinations and imbalances of the humors resulted in various personality types and health conditions, shaping medieval and Renaissance medicine.