Theory of the Four Humors

Overview

• Important ancient medical idea
• Influential during medieval period and beyond
• Based on ideas from Greek philosophers (Aristotle) and Greek doctor Hippocrates

Key Concepts

• Body composed of four humors (liquids):
  • Blood
  • Phlegm
  • Black Bile
  • Yellow Bile
• Linked to four elements and seasons
  • Example: winter/spring = wet and cold = colds and phlegm

Balance of Humors

• Health = balance of humors
• Illness = too much or too little of a humor
• The theory linked health to personality traits

Seasonal Illnesses

• Certain illnesses more common in specific seasons
• Ancient Greeks believed imbalances were due to natural causes (not supernatural)

Treatment Examples

1. Cold Symptoms:

   • Symptoms: shivers, phlegm
   • Cause: too much phlegm
   • Treatment: blow nose or inhale vapors

2. Rash and Fever:

   • Symptoms: redness of skin, high temperature
   • Cause: too much blood
   • Treatment: bloodletting

3. Constipation:

   • Symptoms: inability to go to the bathroom
   • Cause: too little black bile
   • Treatment: laxative foods

Importance of the Theory

• Represents progress in ancient times as a scientific explanation for illness
• Continuity in medieval times, with treatments like bleeding lasting for centuries
• Challenged during the Renaissance but persisted into the 19th century

Final Points

• Four humors: blood, black bile, yellow bile, phlegm
• Illness linked to imbalances in humors
• Theory was rational but incorrect
• Treatments addressed symptoms, not disease causes
• Some treatments (e.g., bleeding) harmful

Conclusion

• Four humors remained a dominant theory for centuries, influencing medical practices.
• The lecture provided an overview of the historical significance and implications of this theory in medical history.