素问·阴阳类论 Discourse on the Categories of Yin and Yang
孟春始至，黄帝燕坐，临观八极，正八风之气，而问雷公曰：阴阳之类，经脉之道，五中所主，何藏最贵。雷公对曰：春，甲乙青，中主肝，治七十二日，是脉之主时，臣以其藏最贵。帝曰：却念上下经阴阳从容，子所言贵，最其下也。雷公致斋七日，旦复侍坐。帝曰：三阳为经，二阳为维，一阳为游部，此知五藏终始。三阳为表，二阴为里，一阴至绝作朔晦，却具合以正其理。雷公曰：受业未能明。帝曰：所谓三阳者，太阳为经，三阳脉至手太阴，弦浮而不沈，决以度，察以心，合之阴阳之论。所谓二阳者，阳明也，至手太阴，弦而沈急不鼓，炅至以病皆死。一阳者，少阳也，至手太阴，上连人迎弦急悬不绝，此少阳之病也，专阴则死。三阴者，六经之所主也，交于太阴，伏鼓不浮，上空志心。二阴至肺，其气归膀胱，外连脾胃。一阴独至，经绝气浮不鼓，钓而滑。此六脉者，乍阴乍阳，交属相并，缪通五藏，合于阴阳，先至为主，后至为客。
雷公曰：臣悉尽意，受传经脉，颂得从容之道，以合从容，不知阴阳，不知雌雄。帝曰：三阳为父，二阳为卫，一阳为纪。三阴为母，二阴为雌，一阴为独使。二阳一阴，阳明主病，不胜一阴，耎而动，九窍皆沈。三阳一阴，太阳脉胜，一阴不能止，内乱五藏，外为惊骇。二阴二阳，病在肺，少阴脉沈，胜肺伤脾，外伤四支。二阴二阳皆交至，病在肾，骂詈妄行，巅疾为狂。二阴一阳，病出于肾，阴气客游于心，脘下空窍，堤闭塞不通，四支别离。一阴一阳代绝，此阴气至心，上下无常，出入不知，喉咽乾燥，病在土脾。二阳三阴，至阴皆在，阴不过阳，阳气不能止阴，阴阳并绝，浮为血瘕，沈为脓胕。阴阳皆壮，下至阴阳，上合昭昭，下合冥冥，诊决死生之期，遂合岁首。
雷公曰：请问短期。黄帝不应。雷公复问。黄帝曰：在经论中。雷公曰：请闻短期。黄帝曰：冬三月之病，病合于阳者，至春正月脉有死徵，皆归出春。冬三月之病，在理已尽，草与柳叶皆杀，春阴阳皆绝，期在孟春。春三月之病，曰阳杀，阴阳皆绝，期在草乾。夏三月之病，至阴不过十日，阴阳交，期在溓水。秋三月之病，三阳俱起，不治自已。阴阳交合者，立不能坐，坐不能起。三阳独至，期在石水。二阴独至，期在盛水。
When early spring had just arrived, Huangdi, seated at leisure, looked out over the eight extremities, rectifying the qi of the eight winds, and asked Lei Gong: Among the categories of yin and yang and the Way of the channels and vessels, and what the five centers govern, which viscus is most honored? Lei Gong replied: In spring, the stems jia and yi correspond to green, and within the body govern the liver, which presides for seventy-two days; this is the viscus that governs the pulse in its season, and so I consider this viscus to be the most honored. The Emperor said: Yet consider the Upper and Lower Canons on yin and yang and unhurried deliberation — what you call honored is in fact the lowest of all. Lei Gong purified himself by fasting for seven days, and at dawn again sat in attendance. The Emperor said: The greater yang forms the warp; the yang brightness forms the linking vessel; the lesser yang forms the roaming region — by this one knows the beginning and end of the five viscera. The three yang form the exterior, the two yin form the interior, and the one yin, reaching its extremity, is cut off and becomes like the darkness of the new moon; one must gather all of this together to rectify its principle. Lei Gong said: Having received this instruction, I am still not able to understand it clearly. The Emperor said: What is called the three yang — the greater yang forms the warp. When the pulse of the three yang reaches the hand taiyin, it is wiry and floating, not sunken; one determines this by measure and examines it with the mind, uniting it with the discourse on yin and yang. What is called the two yang is the yangming; when its pulse reaches the hand taiyin, it is wiry, sunken, and hasty, without a proper beat; if heat arrives, in such disease the patient will die. The one yang is the shaoyang; when its pulse reaches the hand taiyin, connecting upward with the renying pulse, it is wiry, tense, suspended, and unbroken — this is the disease of the shaoyang; if it becomes purely yin, the patient will die. The three yin govern the six channels; their pulse crosses at the taiyin, hidden and beating without floating, and above it leaves the heart and its resolve empty. The two yin reach the lung, their qi returning to the bladder, and externally connecting with the spleen and stomach. When the one yin arrives alone, the channel is severed, the qi floats without a proper beat, and the pulse is hooked and slippery. These six pulses are now yin, now yang; they cross, connect, and combine with one another, intricately linking through the five viscera, uniting with yin and yang. Whichever arrives first is the host; whichever arrives later is the guest.
Lei Gong said: I have exhausted my understanding; having received the transmission of the channels and vessels, and having recited and grasped the Way of unhurried deliberation, in applying it to unhurried deliberation, I still do not know yin and yang, nor do I know male and female. The Emperor said: The three yang is the father, the two yang is the guard, the one yang is the regulator. The three yin is the mother, the two yin is the female, the one yin is the sole envoy. When the two yang and one yin are involved together, the yangming governs the disease; if it cannot overcome the one yin, the pulse becomes soft and stirring, and all nine orifices sink. When the three yang and one yin are involved, if the taiyang pulse dominates and the one yin cannot restrain it, there is disorder within the five viscera and fright and alarm without. When the two yin and two yang are involved, the disease is in the lung; the shaoyin pulse is sunken, overcoming the lung and injuring the spleen, and injuring the four limbs externally. When the two yin and two yang both arrive together in crossing, the disease is in the kidney, causing cursing and reckless behavior, disease of the vertex, and mania. When the two yin and one yang are involved, the disease arises from the kidney; yin qi lodges and roams into the heart, the region below the epigastrium becomes hollow at its orifices, its embankments closed and blocked without passage, and the four limbs become estranged from proper function. When the one yin and one yang alternate and are cut off, this means yin qi reaches the heart; above and below lose their constancy, and its coming and going cannot be known; the throat becomes dry, and the disease lies in the earth, the spleen. When the two yang and three yin are involved, and the utmost yin is entirely present, yin does not exceed yang, yet yang qi cannot restrain yin; yin and yang are both cut off. If the pulse floats, this produces blood accumulations; if it sinks, this produces festering pus. When yin and yang are both vigorous, reaching down to yin and yang below, uniting above with what is bright and clear, and uniting below with what is dark and obscure, the diagnosis determines the appointed time of death or life, and one must correlate this with the beginning of the year.
Lei Gong said: I ask about the imminent time of death. Huangdi did not answer. Lei Gong asked again. Huangdi said: It is contained within the discourse of the classics. Lei Gong said: I ask to hear of the imminent time. Huangdi said: For diseases of the three months of winter, if the disease unites with yang, by the first month of spring the pulse will show signs of death, all converging to appear as spring emerges. For diseases of the three months of winter, when their course of principle is already exhausted, and the grasses and willow leaves are all killed by frost, while in spring yin and yang are both cut off, the appointed time is in early spring. For diseases of the three months of spring, this is called the killing of yang; yin and yang are both cut off, and the appointed time is when the grass withers and dries. For diseases of the three months of summer, when it reaches the utmost yin, it does not exceed ten days; when yin and yang cross, the appointed time is when the waters turn cold. For diseases of the three months of autumn, when the three yang all rise together, the disease will resolve of itself without treatment. But if yin and yang cross and combine, the patient, once standing, cannot sit, and once sitting, cannot rise. When the three yang arrive alone, the appointed time is when the water freezes hard as stone. When the two yin arrive alone, the appointed time is when the waters are at their fullest.