11. All medicine was predicated upon the four humors of the body
The four humors corresponded to health in the human body when they were in balance. They related to the four elements (Earth, Water, Air, Fire,); the four seasons (Autumn, Winter, Spring, Summer, respectively); four organs of the body (Spleen, Lungs, Head, Gall Bladder); and four temperaments (Melancholy, Phlegmatic, Sanguine, Choleric). The humors in the body were also known as the principal fluids and were, correspondingly, Black Bile, Phlegm, Blood, and Yellow Bile. The humors were brought into perfect balance by diet and exercise, and when out of balance the physician based his diagnoses on their presence, or lack of presence. A problem with the lungs, for example, led to the coughing up of phlegm.
Fever was present, in the minds of the medieval physicians, because of too much blood in the body, and the removal of the same restored balance. Imbalances could be relieved and corrected through the use of teas brewed from the corresponding herbs and plants, or salves and plasters applied to the afflicted area of the body. Physicians of the period also prescribed prayer and penance, since the Christian belief was that sickness was a punishment from God. The use of medications and treatments without a corresponding commitment to prayer and penance was in itself considered sinful, as it was defiance of the will of God. Christian teaching influenced the development of medicine throughout the medieval period, both in the formal training in universities and hospitals and in the practice of folk remedies and cures.