Library

The Three Yang meridians have only Yang patterns and no Yin patterns; the Three Yin meridians have Yin patterns and also deficiency patterns. Most people are aware of this. However, regarding Yang patterns in the Three Yin meridians, there are those who do not understand. Zhang Zhongjing deeply feared that future generations would be confused by this, so he detailed notes stating: Those who first experience fever in the Yang meridians and then transmit to the Three Yin meridians are suffering from a heat disease transmitted via meridians, named Shanghan (Cold Damage), which corresponds to the clauses on heat diseases mentioned in the *Neijing* (Inner Canon); if there is no fever at the onset, it is a cold disease where pathogenic cold directly strikes the Yin meridians, named Yin pattern. Later practitioners, seeing both Yin and Yang patterns in the same chapter, mistakenly believed that heat diseases transmitting to the Three Yin meridians are also Yin patterns; they further mistakenly believed that although there was a heat disease at the onset, if after a long time the hands and feet become cold and the six pulses are deep and fine, it has already transformed into a Yin disease. They did not realize that the initial fever is already the root of the heat disease; whether due to failure to dissipate the exterior pathogen leading to its internal collapse, or failure to clear the interior heat leading to its internal retention, upon transmitting to the Yin meridians, the hands and feet may paradoxically become cold. Although the meridians belong to Yin, the symptoms manifest as Yang patterns; this is actually a heat disease of the Yin meridians, not a transformation into a Yin pattern. For example, in Taiyin disease where the hands and feet are naturally warm, jaundice should develop; in Shaoyin disease with only cold extremities and no sweat; in Shaoyin disease with vexation in the heart and inability to lie down; in Shaoyin disease with diarrhea, sore throat, and vexation; in Shaoyin disease with diarrhea for six or seven days, vexation, and inability to sleep; in Shaoyin disease with spontaneous purging of clear water and必 (must) pain in the epigastrium; in Jueyin disease with diarrhea, rapid pulse, and thirst; in Jueyin disease with diarrhea, rapid pulse, and slight fever; in Jueyin disease with diarrhea and desire to drink water; in Jueyin disease with vomiting, fever, diarrhea, and delirious speech—all these are heat diseases of the Yin meridians, mostly treated with Chengqi Tang (Gut-Draining Decoction). Since the heat has transmitted to the Yin meridians, the deeper the heat, the deeper the cold extremities (Jue); the body may paradoxically feel no heat, and the pulse may paradoxically be deep and fine. But one must not forget that in cold extremities due to heat, the hands and feet can originally move, unlike cold extremities due to Yin-cold, where the hands and feet are cold and immobile. Although the body is not hot, the lips and mouth will inevitably be dry and scorched, unlike Yin patterns where the mouth is neutral and moist. The pulse is deep and fine; upon heavy pressure, it must be fine and rapid, unlike Yin-cold patterns where the pulse is deep, fine, and slow. There is an even greater distinction: In Three Yin cold diseases, the spirit and consciousness are clear; in Three Yin heat diseases, the spirit and consciousness are confused or comatose; in Three Yin cold diseases, even if the mouth is dry, drinking is impossible; in Three Yin heat diseases, if the mouth is dry, drinking is inevitable; in Three Yin cold diseases, urination and defecation are clear and free-flowing; in Three Yin heat diseases, urination and defecation are red, scanty, and difficult. One Yin and one Yang, their natures are as different as Heaven and Earth.