Complexion refers to the natural color, texture, and appearance of the skin, especially that of the face.
The word "complexion" is derived from the Late Latin complexi, which initially referred in general terms to a combination of things, and later in physiological terms, to the balance of humors.
The four humours were four fluids that were thought to permeate the body and influence its health. The concept was developed by ancient Greek thinkers around 400 BC and developed further by Galen. People were thought to be either of the four temperaments: choleric, melancholic, phlegmatic, or sanguine.
During the Middle Ages in Europe, the Latin term complexio served as the translated form of the Greek word crasis, meaning temperament. The term “temperament” referred to the balance of the qualities of hot, wet, cold, and dry; each human body carried a different mixture of the elements. Thus, the Scythians, who lived in a cold climate, were considered “colder and moister” in complexion; the Ethiopians were considered hotter and dryer. Complexion was defined as “that quality which results from the mutual interaction and interpassion of the four contrary primary qualities residing within the elements. These elements are so minutely intermingled as each to lie in very intimate relationship to one another. Their opposite powers alternately conquer and become conquered until a quality is reached which is uniform throughout the whole: this is the complexion.”
As Matthew Simon writes, “Since it served as a fundamental concept, not only in physiology but also in pathology and therapy, complexion theory provided important support for the idea that medicine constituted a unified and rational body of knowledge.” By observation and judgment, medieval physicians determined the proper complexion of the individual when healthy. The body was healthy when all was in balance, but diagnosis was difficult, as there was no absolute measure of the right complexion, since this varied for individuals. Balance was thought to be restored by various remedies, which included bloodletting, scarifying, purging, and eating certain foods.