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Traditional Chinese Medicine Causes of Illness


The Six Pernicious Influences

The six pernicious influences, also known as the six pathogenic factors, six excesses, or six evils, are the causes of disease that often arise from outside the body. They are wind, cold, heat, dampness, dryness, and summer heat. Although Western medicine recognizes only viruses and bacteria as external pathogens, the Chinese observed that the body mirrors certain climatic conditions.

Although a diagnosis of "wind and cold invading the lungs" might sound primitive, this type of diagnosis accurately describes the way a certain type of pathogenic factor behaves inside the human body. The wind symptoms act just like wind in nature: They come and go, often without warning.

Similarly, the cold symptoms act as they do in nature: they cause contraction, they slow functions down, and they make the person feel cold. The high degree of effectiveness in treating this type of disorder (such as with herbs that "repel wind and scatter cold") is proof that the diagnosis is much more than a mere philosophical idea. Although Western medicine might be able to isolate the virus causing this condition, it still has no safe and effective way of treating the virus, other than relieving some of the symptoms it causes. On the other hand, thousands of years of trial and error through observation of nature and the human body have led to numerous effective treatments in Chinese medicine for viral infections that fit this pattern.

When learning about and discussing the various internal "climates" of the human body, it is important to remember that they may not always match the external climate. It is quite common for a person to develop symptoms of cold and dampness in rainy winter weather, but it is also possible to develop heat symptoms under the same weather conditions. Illness is the combination of the particular pathogen involved and a person's unique response to it. It is also possible for the pernicious influences to arise from internal causes. In this case, they usually result from a chronic internal imbalance. Descriptions of the six pernicious influences follow.

Go to the next page to learn about wind, the first pernicious influence in traditional Chinese medicine.

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