The Six Syndromes classification is the legacy of the great Han physician of the 2nd century, Zhang Zhong Jing, who resigned as a district governor to become a doctor. This gesture illustrating his genuine love for medicine and care for people was even more impressive when we know that in his time, a governor’s life was comfortable and luxurious, whereas a doctor’s was generally poor and often lonely. His sacrifice, nevertheless, turned out to be a great blessing for the people, because this Six Syndromes classification devised by Zhang Zhong Jing to diagnose contagious diseases, saved thousands of lives during an epidemic in ancient China.
The terms used in this classification are the same as those for the primary meridians, namely taiyang (major yang), yangming (bright yang), shaoyang (minor yang), taiyin (major yin), jueyin (final yin), and shaoyin (minor yin), but their meanings are quite different. Here, they represent six typical conditions of the patient’s reaction against diseases, particularly those caused by external factors.
The chief characteristics of taiyang (major yang) illnesses are “floating pulse, headache and being afraid of cold”. It is usually found in infectious diseases at the superficial or initial stage.
Yangming (bright yang) illnesses shows typical symptoms such as “body warmth, big pulse rate, and solid stomach system”. (“Solid stomach system” refers to a stagnation of energy or sthenia-syndrome at the gastrointestinal tract due to heat-evil) Yangming syndrome indicates that infectious diseases have developed into the advanced stage.
The stage between taiyang and yangming is shaoyang (minor yang), with characteristics of “bitter mouth, dry throat, and blurred eyesight”. This syndrome shows that infectious diseases have reached the intermediate stage, but have not developed into the internal organs.
Taiyin (major yin) illnesses usually involves the spleen and the stomach, and its nature is cold and empty. (An “empty” disease refers to a disease where the body’s physiological functions have been weakened, and the causes of the disease are not obvious.) The chief characteristics of taiyin illness include “full stomach, vomiting, stomach ache, and no desire for food”.
On the other hand, the chief characteristics of jueyin (final yin) illness are “pain at the heart, hungry but with no desire to eat, and vomiting if eaten”. This is an advanced stage of infectious diseases, where the body defence has been much weakened.
The main symptoms of shaoyin (minor yin) illness are “weak pulse, wanting to sleep, being afraid of cold, cold limbs, and liquid faeces”. This syndrome is indicative of energy deficiency of the heart and kidney systems, with cold and empty nature.
concerning the nature and the developmental states of illness. This classification of illness according to six archetypical syndromes is particularly useful for contagious diseases. Broadly speaking, diseases are divided into two main types according to the relationship between the potency of pathogenic agents, especially those of an infectious nature, and the efficiency of the patient’s own defence system. If it is obvious that pathogenic agents are mainly and actively responsible for causing the illness, the disease is classified as yang. On the other hand, if the chief causative factor is the weakening of the patient’s own bodily systems, though exo-pathogens may also play a role in the illness, the disease is classified as yin.
Further, both yin and yang diseases are classified into three sub-types according to their developmental stages. Thus, yin diseases at the initial, intermediate and advanced stages are classified as taiyin, shaoyin and jueyin respectively. Yin diseases are those that occur because the patient’s natural systems are too weak to contain pathogenic agents, irrespective of whether these agents have been inside the patient’s body all this while or have just entered his body. Yang diseases at the initial, intermediate and advanced stages are termed taiyang, shaoyang and yangming. Yang diseases are those that occur because of the potency of exogenous pathogens, even though the patient’s natural systems may still be operating as usual.
It may be useful to remember that “tai” and “shao” which are prefixed to “yin” and “yang” in the above terminology, mean “major” and “minor” respectively, suggesting the start and the continuation of the body’s weakening or the pathogens’ attack. “Jue” prefixed to “yin”, and “ming” suffixed to “yang”, mean “final” and “bright”, indicating that the body’s defence has been drawn to its last stage, or the pathogens’ attack is most intense. This ingenious classification of diseases by one of China’s greatest physicians is both simple and effective. Western medical scientists, while maintaining their own mode of diagnosis and therapeutics, may draw some inspiration from such medical thinking.
Three Levels
Although the Six Syndromes system was developed in the ancient time by Zhang Zhong Jing, it is so useful against contagious diseases that it has been successfully employed by Chinese physicians until now. Another historic development was made in the 17th century, two centuries before bacteriology was established in the west, when Wu You Xing (1582–1652) who braved possible fatal infection to study pestilent diseases, discovered that plagues, unlike other contagious diseases, were caused by “sinful energy” which consists of microscopic organisms that spread through the air. This led to the development of “wenyi” (virulent epidemic) diseases as a specialty from the other contagious diseases generally referred to as “shanghan” (cold and fever) diseases.Later, Wu Ju Tong (1736–1820) synthesized past masters’ invaluable knowledge on plagues which had swept China previously, and devised the Three Levels classification for pestilent diseases. In Chinese, this Three Levels classification is called “san jiao classification”. As “san jiao” is also the term for “triple warmer”, it is easy for many people to mistake it as “triple warmer classification”, again illustrating how easily Chinese medical thought can be misinterpreted by reading materials from honest writers who may lack the necessary linguistic or technical information, even though these writers may be eminently trained in their own fields. The Three Levels classification actually refers to the three distinctive developmental phases of virulent diseases.
At the first level when the disease first started, it is found at the lung meridian. Why must it be at the lung meridian, and not elsewhere? It is because the microbes that cause these virulent diseases are spread through the air, and breathed in by the patient into his lungs. Common symptoms include headache, slight fear of cold, thirst, and cough. The patient’s pulse becomes frequent; the “cun” (inch) region of the wrist indicates strong pulse, while the “chi” (foot) region indicates warmth. The patient feels warm after noon.
The second level is the intermediate stage of the virulent disease, when its manifestation is found in the spleen and the stomach meridians. If we recall our study of man’s internal cosmos, we shall find that the lungs provide essential energy for the colon for its operation, and the colon is intimately connected to the spleen and stomach systems. Hence, if attacking microbes are not checked at the lungs, they spread to the spleen and stomach via the meridian network. The patient is feverish but he is not afraid of cold. Common symptoms include reddened face, rough respiration, yellowish fur on tongue, and solid faeces. The patient’s condition worsens in the afternoon, such as feeling muddled in his thinking, body heavy, no desire for food, wanting to vomit, whitish fur on his tongue, and difficult urination. As the illness develops into the third level, it is manifested in the kidney and the liver meridians. Our study of man’s internal cosmos explains that the stomach and the spleen are responsible for the production and regulation of nutrient essence, which in turn