I think history is important. Maybe we didn't have microscopes or DNA but we were not sidelined by twitter and TV - and we wrote with lovely handwriting and made terrific observations. Even in the West. Careful observation and history give us the tenets of the paleo diet. From anthropology we learn the concept of the "nutritional transition" from relative health to relative disease.
And in the West, medicine begins with Hippocrates (460-370 BC) and his work, Nature of Man. He was (of course) building on ancient observations and wisdom himself, but from this point we are looking at translated written records, so this is where we must begin.
The nature of humors as such comes from empirical medicine. The notion of the tetrad, the definition of health as the equilibrium of the different parts, and of sickness as the disturbance of the equilibrium, are Pythagorean contributions… The notion that in the course of the seasons each of the four substances in turn gains ascendancy seems to be purely Empedoclean. But the credit for combining all these notions in one system, and thereby creating the doctrine of humoralism which was to dominate the future, is not doubt due to the powerful writer who composed the first part of… [Nature of Man]… from this… evolved the following schema, which was to remain in force for more than two thousand years.
Humor Season Qualities
Blood Spring warm and moist
Yellow Bile Summer warm and dry
Black Bile Autumn cold and dry
Phlegm Winter cold and moist
In ancient times, the seasons were linked with the four ages of man - Youth, Manhood (Prime), Decline, and Old Age (counted in Ancient times as 0-20, 20-40, 40-60, 60-death - suggesting that ancient agricultural ages corresponded roughly to our own (so much for statins)).
Mental illness in general was derived from the concept of "black bile" - which was interestingly seen to be a perturbation of normal yellow bile from excessive heat or cold (either via environment or via intemperent passions). Black bile in its time was held to be responsible for a great number of diseases, including headaache, vertigo, paralysis, spasms, epilepsy, and other mental disturbances, to diseases of the kidney, liver, and spleen.
in this as in other cases the Greeks based their theories on observations. We know that the stool of patients suffering from bleeding gastric ulcers is black, as sometimes are the substances vomited by patients with carcinoma of the stomach. A form of malaria is still known as "blackwater fever" because the urine as a result of acute intravascular hemolysis suddenly becomes very dark, if not black… similar observations may have led to the assumption that ordinary yellow bile through corruption could become black and that this black bile caused diseases, notably… melancholy."Melancholy" is derived from ancient Greek words that, via Latin, are translated to "black bile" in English. For two thousand years, "melancholia" defined the clinical term we now call "depressive disorders" in addition to the moods and states of sadness and loss (though they were often described as "melancholy" rather than "melancholia.")
Plato felt that the blood was made of two parts, "the watery part" which was innocent, and the part that is "a secretion of black and acid bile" which is potentially malignant. He felt pathologic forms of "the humors" had the potential to wander around the body, and finding "no exit or escape" become "pent up within and mingle their own vapours with the motions of the soul."
By the time of the Middle Ages and Renaissance, variant in the Black Bile theory had come to the fore. There was not only "natural" black bile, but also "burnt black bile" derived from combustion of yellow bile in the absence of fever that provoked "violent delerium… because it occupies the substance of the brain itself." In time, the concept of unnatural black bile evolved so that the process of burning or combustion of the four humors could lead to the bitter black bile, thus it became common to think of four types of black bile derived from the four humors. The causes suggested for such a process were improper diet, physiological disorders, and immoderate passions. The burning process would lead to hot melancholy, which would be followed in turn by cold melancholy.
In ancient Western medicine, the term "non-naturals" referred to a group of environmental factors related to the disease process: 1) air, 2) exercise and rest, 3) sleep and wakefulness, 4) food and drink, 5) excretion and retention of superfluities, and 6) the passions and perturbations of the soul. For hundreds of generations, management of the patient by a physician involved addressing issues with these six factors and bringing the "whole organism" back to equilibrium. (In modern times we call the "non-naturals" model the "Biopsychosocial model" of psychiatric diagnosis.)
By the 18th and 19th centuries, the discovery of microorganisms and other issues leading to pathologic states fed into this model. Just what is disease, anyway?
Disease is the aggregate of those conditions which, judged by the prevailing culture, are deemed painful, or disabling, and which, at the same time, deviate from either the statistical norm or from some idealized status. Health, the opposite, is the state of well-being conforming to the ideals of a prevailing culture, or to the statistical norm.In a more practical sense, "disease" is "a pattern of factors which somehow hang together and recur, more or less the same, in successive individuals." The theories of causative factors have varied over the years, from perturbations of the "six non-naturals" to microbial attack to demonic possession. A symptom is something described by the suffering individual, a sign is something observed by others. A disease is a combination of anatomical, physiological, biochemical, and psychological deviations from the norm that comprise the basis of symptoms and signs.
In any event, "disease" is a deviation from the norm, something added to the healthy state to bring on illness. "Outside" element theories (such as demonic possession) dictated a treatment of removing the offending element. "Inside" element theories involved paying attention to the individual as well as the nature of the disease to best affect a cure. These theories do not differ too significantly from our models of disease and treatment today.
In all cases, disease is relative, varying from culture to culture. Some mental states are considered in all history and culture as distinctly unusual, in other cultures, the mentally ill are considered sinners, with the unusual mental states being reflections of the sins. Others have been thought of as prophets or holy men, and have been honored rather than treated.
I bring up this history because we have to understand that even our modern Western understanding of disease reflects these ancient biases. There are perturbations and demons, strength of moral fiber or lack of temperance. Add in microorganisms, character, maladaptive coping strategies, trauma, genetics, diet… we learn from history the same lessons over and over. It behooves us to listen to our ancestral nutritional and lifestyle programming. The more things change, the more things stay the same.