Difficulty 49

There are cases where a regular channel itself becomes diseased, and there are also cases where it is invaded by the five types of pathogenic qi. How are these distinguished?

The reply says: According to the medical classic, excessive worry and overthinking harm the heart; exposure to cold and consuming raw or cold food harm the lungs; anger and rage cause the qi to rebel and surge upward without descending, harming the liver; irregular eating and drinking and overwork harm the spleen; prolonged sitting in damp places or forcing oneself to enter water when tired harms the kidneys. These are cases where the regular channel itself becomes diseased.

What are the five pathogenic influences?

The reply says: There are wind stroke, summerheat injury, dietary irregularity and overwork, cold damage, and dampness injury. These are called the five pathogenic influences.

Suppose it is a heart disease; how does one know it is caused by wind stroke?

The reply says: The patient's complexion should be red. Why is this said? Because the liver governs color. When the liver's pathogenic qi invades its own organ, it manifests as green; when it invades the heart, it manifests as red; when it invades the spleen, it manifests as yellow; when it invades the lungs, it manifests as white; when it invades the kidneys, it manifests as black. The liver's pathogenic qi invades the heart, therefore one knows the complexion should be red. This disease manifests as heat in the body, fullness and pain below the ribs, and a pulse that is floating, large, and wiry.

How does one know it is caused by summerheat injury?

The reply says: The patient should have an aversion to foul odors. Why is this said? Because the heart governs odors. When the heart's pathogenic qi invades its own organ, it manifests as a scorched odor; when it invades the spleen, it manifests as a fragrant odor; when it invades the liver, it manifests as a rank odor; when it invades the kidneys, it manifests as a putrid odor; when it invades the lungs, it manifests as a fishy odor. Therefore, one knows that heart disease caused by summerheat injury should involve an aversion to foul odors. This disease manifests as heat in the body with vexation, heart pain, and a pulse that is floating, large, and scattered.

How does one know it is caused by dietary irregularity and overwork?

The reply says: The patient should have a craving for bitter flavors. In deficiency, it manifests as an unwillingness to eat; in excess, it manifests as a desire to eat. Why is this said? Because the spleen governs flavors. When the spleen's pathogenic qi invades the liver, it manifests as sourness; when it invades the heart, it manifests as bitterness; when it invades the lungs, it manifests as pungency; when it invades the kidneys, it manifests as saltiness; when it invades its own organ, it manifests as sweetness. Therefore, one knows that when the spleen's pathogenic qi invades the heart, there will be a craving for bitter flavors. This disease manifests as heat in the body with heaviness and somnolence, weakness and slackness of the four limbs, and a pulse that is floating, large, and relaxed.

How does one know it is caused by cold damage?

The reply says: The patient should exhibit delirious speech. Why is this said? Because the lungs govern sound. When the lungs' pathogenic qi invades the liver, it manifests as shouting; when it invades the heart, it manifests as speech; when it invades the spleen, it manifests as singing; when it invades the kidneys, it manifests as groaning; when it invades its own organ, it manifests as weeping. Therefore, one knows that when the lungs' pathogenic qi invades the heart, there will be delirious speech. This disease manifests as heat in the body, intermittent chills, and in severe cases, panting and coughing, with a pulse that is floating, large, and rough.

How does one know it is caused by dampness injury?

The reply says: The patient should exhibit incessant sweating. Why is this said? Because the kidneys govern fluids. When the kidneys' pathogenic qi invades the liver, it transforms into tears; when it invades the heart, it transforms into sweat; when it invades the spleen, it transforms into saliva; when it invades the lungs, it transforms into nasal discharge; when it invades its own organ, it transforms into spittle. Therefore, one knows that when the kidneys' pathogenic qi invades the heart, there will be incessant sweating. This disease manifests as heat in the body, pain in the lower abdomen, coldness and reversal of the lower legs, and a pulse that is deep and large but soft when pressed. This is the general method for the five pathogenic influences causing disease.