This is published here because of our interest in ancient greek medical theory. We do not necessarily endorse the ideas. The “Unani” part of Unani Tibb Medicine, that is, the elements from Greek medicine that the Islamic doctors adopted as part of Islamic medicine, does give some background to the theories that held sway with, for example, Ibn Sina.
Greek Medicine from Hippocrates to Galen: Studies in Ancient Medicine Edited by John Scarborough Philip J. van der Eijk Ann Ellis Hanson Joseph Ziegler write,
“The anonymous author presents the theory of the four temperaments in the form of a response to a question about differences between characters.
How does it occur that amongst men, some are gracious, laugh and make jokes, others are sad, with a sombre air and doleful, others are quick-tempered, bitter and given to anger, others indolent, hesitant and pusillanimous? The cause is this, based on the elements:
Those who are composed of very pure blood are always friendly, joke and laugh; regarding their bodies, they are rose-tinted, slightly red and have pretty skin.
Those who are composed of yellow bile are quick-tempered, bitter, daring; regarding their bodies, they are greenish and have yellow skin.
Those who are composed of black bile are indolent, pusillanimous and sickly; regarding their bodies, they have black eyes and black hair.
Those who are composed of phlegm are despondent, forgetful; regarding their bodies, they have white hair.”