Humoral Theory
Humoral Theory is an ancient medical concept that suggests human health is governed by four bodily fluids, or "humors": blood, phlegm, black bile, and yellow bile. Each humor is associated with specific qualities—hot, cold, wet, and dry—and an imbalance among them was believed to cause illness. This theory was prevalent in ancient Greece and Rome, influencing medical practices for centuries.
The theory was notably advanced by the Greek physician Hippocrates and later by Galen, who linked the humors to the four elements: earth, air, fire, and water. Although Humoral Theory has been largely replaced by modern medicine, it laid the groundwork for understanding the relationship between body and health.