humors

Humors are an ancient medical theory suggesting that health depends on the balance of four bodily fluids: blood, phlegm, yellow bile, and black bile. Imbalances among these humors were believed to cause different physical and mental health issues. For example, excess blood was thought to cause sanguine, cheerful traits, while too much black bile was linked to melancholy. Although modern medicine no longer supports this concept, historically, the humors influenced diagnostic and treatment practices until scientific understanding of anatomy and physiology advanced.