Medieval Medicine - Four Humors and Four Temperaments

Humoral theory isn’t meant to be funny, but it most certainly is.

Humorism or humoralism was the basis for medical diagnosis and treatment in the medieval period, and its use continued into the 1700s. That’s already three different names, but they mean the same thing: Four bodily fluids determine a person’s temperament or personality, and sickness results when these humors are out of balance. Humors are connected to the planets, the seasons of the year, specific internal organs, and stages of life. Obviously.

Way back in 400 BC, Hippocrates revolutionized medicine in Ancient Greece with the notion that sickness and disease were not punishment from the gods, but naturally occurring phenomena due to one’s diet, environment, and lifestyle.

A person’s health required an equilibrium between the four main humors: blood, phlegm, yellow bile, and black bile. Keep them in balance and you’ll have good health. Each humor was related to the four elements (earth, wind, fire, water) and the four primary physical qualities: hot, cold, wet, and dry.

600 years later, Galen would build on the theory to locate humoral imbalances in specific organs (brain, heart, gallbladder, spleen) and associate them with the proper celestial bodies (Jupiter, Saturn, Mars, and the moon.)

In the Roman Empire, physicians based their treatments on Galen’s writings and prayers to Asclepius, the Greco-Roman god of healing. Annoyingly similar to your doctor today, Galen recommended lots of sleep, a healthy diet, and vigorous exercise to maintain one’s health. Galen also recommended regular bathing for good health, and hopefully your doctor has not felt the need to mention this to you.

Around 1000 AD, Avicenna dove into the ancient Greek and Roman texts and built on the humoral theory to expand into the Four Temperaments. Dividing people into categories of hot or cold plus wet or dry, Avicenna invented the world’s first personality test.

Melancholic people have a reserved, thoughtful, reflective, and introverted nature.

Phlegmatic people are calm, unemotional, patient, reliable, and relaxed.

Sanguine people are outgoing, sociable, enthusiastic, impulsive, and optimistic.

Choleric people are impatient, prone to anger, ambitious, and goal-oriented. (Also, they were thought to be the best leaders. Sound like any boss you know 1,000 years later?)

The humoral theory provided a framework for understanding health and disease, with an explanation for a patient’s symptoms and treatment a doctor (or barber) could provide. Humoral theory was based on the wisdom of the ancients and written into all the textbooks that were taught at all the medical schools, so it was the primary way medicine was practiced for over 2,000 years.

Granted, it’s all nonsense, but there is a logic to the way it ordered the universe from the skies to the body. When you ain’t got nuthin’ else, it’ll have to do, right? The four humors are scattered throughout the words and actions of the characters in Shakespeare's plays and are part of modern English language today.

Lucky for you, the practice of medieval medicine became modern medical science, and you have vaccines and antibiotics and endless waiting on hold with your insurance company. Oh, and doctors’ bills. Some things never change.

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