What is often referred to as galenic medicine survived as a working medical system from the time of the ancient Greeks to the start of the industrial era. Galen’s four humours were embedded in a medical and philosophical system of interactions between elements that made up the world. This holistic model emphasised balance and harmony as the basis for health.
According to classical Greek theory, the world was made up of four elements air, earth fire and water. Four qualities, hot, cold, dry and wet, combined with the four elements, four seasons and four temperaments, sanguine, melancholy, choleric and phlegmatic. In the galenic system, the four temperaments were manifested in animal bodies in blood, black bile, yellow bile and phlegm.
For the medical aspect of Galenic theory, the following combinations were central to understanding, diagnosing and treating illness.
Blood formed in the liver [and carried to the heart via an artery] and travelled through the veins and arteries to the other organs, dissolving outwards via the skin. It also carried small amount of the other 3 humours. It had hot and wet qualities, and was associated with air, childhood and spring.
Black bile was produced in the spleen and travelled to the liver via a canal, held in and secreted by the spleen and excess concentrations in specific areas considered to cause cancer It had cold and dry qualities, and was associated with earth, maturity and autumn
Yellow bile was produced in the liver and contained in the gall bladder or secreted as vomit and faeces. It had hot and dry qualities and was associated with fire, youth and summer.
Phlegm was formed in the brain and consisted of white or colourless secretions such as pus, mucus, saliva and sweat. It had cold and wet qualities, and was associated with water, old age and winter
The 4 humours and temperament together had a significant role in determining personality:
Blood - sanguine temperament, characterised by enthusiastic, active and social personalities
Black bile - melancholy temperament, characterised by sad and reflective personalities, and it could lead to mental illness and madness
Yellow bile - choleric temperament, characterised by ambitious, decisive, aggressive and short-tempered personalities
Phlegm - phlegmatic temperament, characterised by reserved personalities
Galenic medical treatment was based on what is often called heroic medicine. This shocked the body back into balance by a strong therapy that was opposite to or removed excess of the humour linked to the illness.
There were competing theories which challenged the galenic model. One of the most important was Paracelsian medicine. It came out of classical Greek theories of alchemical links between the body and the astronomical bodies in the cosmos. There were metals that corresponded to the planets and stars, especially mercury salt and sulphur.
This theory stated that the body contained 4 tempers, linked to the four kinds of taste, sour (melancholic), sweet (phlegmatic cold and moist), bitter (choleric) and salty (sanguine). Diseases were treated with an similar element to the one out of balance, rather than an opposing one. This system was developed in the 1500s and popular in the 1600s. Although many elements of paracelsian medicine ended up incorporated into mainstream medical therapies, the model had the same issues and flaws as the system it was challenging.
Paracelsian theory supported the development of the study of chemistry which began to isolate elements and identify the substances which made life possible. By reducing the Greek elements into parts, chemistry began to challenge the classical view of what the world was made up of.Another challenge came from anatomical studies of human corpses, which made large chunks of Galen’s anatomical texts obsolete. Andreas Vesalius was one of the most famous of the growing group pf people publishing accurate anatomical studies from the 1500s onwards. Medical scientists who studied the body and drew non galenic conclusions from observation and experimentation became the norm, rather than the exception, over the 1600s and 1700s.
William Harvey, in 1628, proved the heart was a pump, circulating blood around the body via the lungs, using arteries and veins. The effect of an infected wound or venomous bite around the whole body was now explained, and how blood affected observable differences in appearance (blushing etc). However, for a while, the blood and heart just became the new centre of the body, replacing the liver at the heart of Galen’s system.
In the 1640s, J.B. Van Helmont, a Flemish scholar, described over a dozen gases, and identified that gastric juices were acidic. This meant excess acidity was one cause of digestive issues and alkaline solutions could treat it. There was no black bile in the spleen, and it wasn’t present in urine. This meant it couldn’t be a tool for diagnosing humoral illnesses. In fact, normal bile had a positive function related to the stomach which was central to the body. Van Helmont condemned bloodletting, purgatives and laxatives as ineffective.
In the 1650s Thomas Willis produced a new anatomical study of the brain and nerves, observing the effect fever had on mental capacity. The discovery that the brain was the seat of our mental capacities, and ongoing discoveries in the 1700s on the functions of the nervous system, including the sympathetic nervous system were often still presented in humoral terms. This was beginning to transform ideas of mental illness. These slow but important changes in how mental illness was viewed and treated, led to the development of psychiatry as a medical specialism in the 1800s.
As the 1600s and 1700s progressed, a partial understanding of how parts of the human body worked was starting to emerge. There were few working models of how the bodily systems interacted, so galenic theory remained. Most medical practitioners continued to follow traditional therapeutic models, despite the many advances in scientific knowledge.
By the end of the 1700s, mesmerism and electricity were being incorporated into therapies, replacing the old purging and bloodletting therapies to an extent. Although humours were fully discredited as real substances by the 1800s, bloodletting and mild purging remained standard therapies well into the new century.
From the 1850s onwards, advances in chemistry, physiology, germ theory etc., as well as new theories on epidemiology based on understanding of transmission vectors and the sources of diseases, combined to produce new therapeutic models. Although, the classical Greek idea of a balanced life (in terms of exercise and diet) is still the basis of many preventative systems, medical science from the 1900s has discarded the galenic therapeutic models which dominated medical practice for centuries.
