The Predominant Medical Theory in Mid to Late Period Europe, for Ship Surgeons.

Jack Goodfellow

Humoral Theory was the predominant medical theory in Europe for many centuries. The founder of modern medicine Hippocrates is often attributed to first applying it to medicine around 400 BCE, and the writings of the Roman physician Galen in the 2nd century CE greatly added to it and popularized it. It started to fall out of popularity in the 17th Century CE, and finally was disproven by germ theory in the latter half of the 1800's. The 4 humors consist of blood, yellow bile, black bile, and phlegm. The Humoral Theory of medicine posited that when these 4 Humors were out of balance people would either get sick or have behavioral changes. The 4 humors were classified as either hot or cold, as well as either warm or dry, making a different combination for each humor. Humoral dispositions were different for everyone, depending on many factors like the climate of an area, age, sex, occupation, and social class. Imbalances were treated with either diet and lifestyle changes, or purging a humor if it was in excess. 

Yellow bile, also known as Choleric, is vomit and feces. a surplus might be treated with a purgative. Black bile, known as melanc or melancholic, is rarely found on its own. a surplus was believed to cause the blackening of the other 3 humors, a surplus might have been treated with a laxative. Blood, or Sanguine, was often treated by bloodletting a different part of the body dependent on the patient's illness. Lastly, Phlegm aka Phlegmatic was respiratory mucus including those found in the lungs and sinuses, and it was treated with a change in diet. 

Of course this is hardly scratching the surface of the level of detail that was put into this medical theory that was the most widely believed in Europe for many centuries up until the 1600's CE.



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