History & Myths in ancient medicine

The four humors illustration

The ancient concept of four humors connected with the seasons and the zodiac .

The four 'humors'

When encountering classical Islamic books on medicine, such as those authored by Imam Suyuti, Ibn al-Qayyim and others, you will come across the concept of the 'four humors'. These attribute hot, cold, dry and wet humors to food and the human body. It is important to clarify that these teachings were not directly conveyed by the Prophet Muhammad (saw). Rather, the scholars of that time utilized the medical knowledge available to them and applied it to the food that the Prophet (saw) may have consumed at that time. Just as contemporary scholars might state that dates are beneficial due to their balanced combination of proteins and carbohydrates, they are employing the knowledge of our own current time.

So, where did these theories of the four homors found in Islamic books originate? During the early period of Islam, as it expanded into new territories, scholars translated works of the prominent Greek medical figures into Arabic and further developed that knowledge. Unfortunately, much of the knowledge during that time was influenced by superstitions and prevailing ideas, which were eventually disproven as scientific progress advanced, particularly in the early 19th century.

Books by Imam Suyuti and Ibn al-Qayyum

Works by Ibn al-Qayyim (b. 1292) and Imam Suyuti (b. 1445)

An example of superstitious belief in medical circles can be found in the origins of the word 'influenza' or flu. The word 'influenza' derives from the Latin term 'influentia', meaning 'to flow into'. It comes from the belief during medieval times that intangible fluid emitted by stars could impact human health. The Italian word 'influenza' originally referred to any disease outbreak attributed to celestial influences. For example, in 1743, an epidemic of catarrh, was referred to as 'influenza di catarro' in Italian, which spread throughout Europe, eventually leading to the adoption of the term 'influenza' in English.

During the medieval era, physicians also incorporated astrology into their practices, convinced that the movement of stars exerted an influence on human well-being. The term influenza thus reflects the belief in the planetary influence on health. Different parts of the body were associated with specific astrological signs. And medical procedures like bloodletting, were performed only when the moon was in the correct position. Consequently, physicians needed knowledge of both astrology and medicine to effectively treat their patients.

The medieval chart known as the 'Zodiac Man' assigned each body part to a particular star sign, providing guidance for physicians. They would consult a book called the 'Valemecum', which contained charts to determine the appropriate timing for bleeding patients or carrying out other medical procedures. When interpreting a natal chart, the astrologer would determine the temperament of the person, or that person's natural balance between the polarities.

ancient chart

Ancient chart using the four humors

Four Humors, Four Elements and Four Seasons.

The root of ancient medicine is the theory of the 'four humors', with its roots tracing back to the works of Aristotle, Galen and Hippocrates. This theory became an enduring cornerstone of medical belief for a span of two thousand years.

The four humours were:

  • Phlegm
  • Blood
  • Yellow bile
  • Black bile

If the humors stayed in balance then a person remained healthy, but if there was too much of one humor then illness occurred.

ancient chart

The four humors and bile

Additionally, according to the Greeks, all things in existence were composed of four fundamental elements: air, water, fire, and earth. These elements were intricately linked to the cycles of the four seasons as follows:

  • Yellow Bile with Summer
  • Black Bile with Autumn
  • Phlegm with Winter
  • Blood with Spring.

Hippocrates and his fellow Greek practitioners argued that the balance of the four humors would be most affected during these specific seasons.

As an illustration, if someone exhibited symptoms of fever, it was believed that an excess of blood was present in their body. The logical approach, therefore, was to 'bleed' the patient as a remedy.

Another prevailing concept during that time was the principle of 'curing through opposites'. For instance, an imbalance caused by excessive heat required treatment with cold, while an imbalance caused by dryness necessitated moistness as a remedy and vice versa.

Imbalances could also arise from factors such as food, weather, and various activities, as they, like the humors, exerted distinct effects on the primary qualities. For example, winter was perceived to have a cooling and moistening influence on the well-being of individuals.

Islamic medicine

In Islamic and European medicine, humors were key to understanding health and balance. 'Unani Tibb' is a common term used in Islamic medicine but it still uses humors as the basis for diagnosis and treatment. Because it is based on Ibn Sina's interpretation and development of Galen's ideas. So when the early Muslim scholars come into contact with these theories, they adopted them as they were the leading science of the time.

According to 'Unani Tibb', the process of converting food into bodily substances gives rise to four essential humors, namely, blood (dam), phlegm (balgam), yellow bile (mirra safra), and black bile (mirra sawda). However, they refined and expanded upon the theory in various ways, sometimes even challenging its principles. These modifications included recognizing the potential transformations among the humors themselves, as well as introducing additional faculties to certain humors.

For example, they recognized that there are also contributing factors outside of the human body. These contributing factors are called the six non-naturals (Al-Ashya Ghayr Al-Abiya).

They are:

  1. The ambient air, that is, the environment;
  2. Food and drink, the things ingested;
  3. Sleeping and waking;
  4. Exercise and rest;
  5. Retention and evacuation, that is, urine, stool, constipation, but also sexual intercourse;
  6. The mental state, such as joy, sadness, fear, elation, apprehension and so on, often influenced by personal interactions.


So we can see that a significant portion of inherited medical knowledge in Islamic books, was based on superstitious beliefs, such as zodiac signs and humors, which are not aligned with Islamic principles.

Video: Patrick Kelly - The Four Humors, explained