During this era, there was still a considerable amount of debate with regards to the causes of certain types of illnesses. There were however, a number of theories that people believed would cause their illness.
The first and most widely accepted belief had to do with 4 fundamental liquids which make up the body. These four liquids are: Phlegm, blood, yellow bile, and black bile (Dufala). In an ideal individual, all of these liquids work together in harmony, which means there is no excess of a certain one humour. The humour was thought to vaporize within the body reaching the brain, and is what caused certain behaviours among individuals (Libero). The humours meanings and traits were:
The first and most widely accepted belief had to do with 4 fundamental liquids which make up the body. These four liquids are: Phlegm, blood, yellow bile, and black bile (Dufala). In an ideal individual, all of these liquids work together in harmony, which means there is no excess of a certain one humour. The humour was thought to vaporize within the body reaching the brain, and is what caused certain behaviours among individuals (Libero). The humours meanings and traits were:
- Blood: Associated with the liver, and with the element "air", which is hot and moist. A person with excess blood is said to be sanguine, which is optimistic and positive.
- Yellow bile: Associated with the spleen, and with the element "fire", which is hot and dry. A person with excess yellow bile is said to be choleric, which is bad-tempered and irritable.
- Black bile: Associated with the gall bladder, and with "earth", which is a cold and dry element. A person with excess black bile is said to be melancholic, which is depressed, and even mentally ill.
- Phlegm: Associated with the lungs and brain, and with the element "water", which is a cold and moist element. A person with excess phlegm is said to be phlegmatic, which is unemotional and calm (Forp).