"In the historical development of biology, as in all other lanes of knowledge, man has often followed false trails". But...wait a minute...maybe they were not all as false as once thought. It is human nature to look for answers, make assumptions, and test and try them until proven otherwise. In the absence of information, humans will insert their own and/or fall back on metaphysics and mysticism. For example, in older times fertilization was believed to derive from aura seminalis; blood in arteries contained pneuma and vital spirits; the brain and nerves held animal spirits identified as a ray of light; and life was due to a vis essentialis. Ideas such as these may seem like utter to us today, but they must be critiqued with the context and framework of their times when they were thought be satisfactory explanations. Actually, some of these make some sense today and one can see how ancients arrived at these conclusions...their conclusions may have been erroneous, but were "valid" based on what they observed at the time. It was believed there were four principal humors in the body and their interaction dictated the health of a person. This lead to a system of medicine call Humoral Pathology which accounted for diseases and methods of treatment. Humoral Pathology was rooted in the Four Elements: fire, earth, water, and air. These are not actual elements as we know them today, but the belief was similar in that it was believed that varying combinations of these elements composed all matter. The Four Elements were regulated by the Four Qualities: hot, cold, wet, and dry; each element was a compound of two of these qualities. As shown in the figure, fire was hot and dry, earth was cold and dry, water was cold and wet, and air was hot and wet. These kind of made sense in accounting for different types of earth (e.g., one dryer and colder than another, or colder but less dry). Or, that when a substance tended more toward the wet, then it no longer was earth, but became water. The Four Humors were phlegm, blood, yellow bile, and black bile. Today we know these as having different meanings. We now know that blood is a combination of many substances and not a single simple fluid; phlegm is a mucus secretion; yellow bile a digestive enzyme secreted by the liver and stored in the gall bladder; black bile was probably based on their observation of thick dark blood. Blending or mixing the humors was to temper or complexion them. It was believed that if they were all present in the proper proportions, then a person was healthy. But, deficiencies or excess of one or more produced sickness or disease. Expressions such as "bad temper" or "ruddy complexion" once had root in medical diagnoses, but have lost those meanings over time. Treatment of diseases were developed based on balancing the humors. For example, Galen treated patients based on the principle of opposites. If the patient was hot with a fever, he was made cold with compresses. If he was cold and wet (e.g., pneumonia), the excess humor was water so he was made to be kept warm and dry. Although these beliefs have turned out to be not entirely accurate, based on what was known at the time, they made sense. And, some of these beliefs and philosophies surrounding them still make some sense today in holistic approaches to health. "Throwing the baby out with the bathwater" was not a Humoral treatment then, and should not necessarily be done so quickly today. [1] [1] Corrington, J.D. (1960). Wrong Roads in Biology. Beta Beta Beta Biological Society. Vol. 31, No. 4 (Dec. 1960), pp. 205-220. Additional Reading: Cosans, C.E. (1997). Galen's Critique of Rationalist and Empiricist Anatomy. Journal of the History of Biology. Vol. 30, No. 1 (Spring 1997), pp. 35-54.  |