阴阳虚脱，有外因、内因之分，有偏胜、偏绝之别。如邪中于阴，手足厥冷，脉微欲绝，此阴盛而生
阳之气欲绝于内也；如欲冷冻饮料，欲卧凉地，揭去衣被，躁而不安，此阴盛于内而阳欲脱于外也，急宜参、
附、姜、桂以救之；如发汗不解，身反大热，此阳盛而阴绝于内也，如阳明病，发热汗多者，急下之，
宜大承气汤，此阳盛于内而阴液外脱也。此外因之阴阳偏胜而偏绝也。若夫内因之阴阳，阳生于阴，阴生于
阳。阳生于阴者，阳气生于阴精也；阴生于阳者，阴精之生于阳化也。阳化者，阳气化水谷之精微，而生
此精也。阴阳和合，交相生化，是为平人。如孤阳不生，独阴不长，此阴阳之生机欲绝于内也。《难经》
曰∶脱阳者见鬼，脱阴者目盲。盖阳脱者，从下而脱于上；阴脱者，从上而脱于下，故脱阴而目盲者，尚
有余命之苟延，脱阳而见鬼者，不计日而死矣。夫阳脱之患，多有本于阴虚。如年老之人，足膝寒冷，此
元阳之气渐衰，而欲绝于下，宜用参附、半硫之类，以助生阳。如或因脾胃虚而谷精不生，或入房甚而肾
精日损，或忧恐而藏精渐消，或烦劳而精神日耗，以致阴气日衰，而阳将外脱矣。故治未病者，见阴精有
亏，乃阳脱之渐，预培养其阴焉。若待阳气外脱，用桂、附而欲其引火归原，不知阴精者，阳气之生原
也，其原已绝，又安所归乎？故阳脱而用桂、附救之者，外因之脱也；治内因而用桂、附者，助阳气之衰
于下也。（若阴虚而阳脱者，非桂、附可救。）故曰阴阳虚脱，有外因、内因之分，有偏胜、偏绝之别。
阴阳虚脱，有外因、内因之分，有偏胜、偏绝之别。
阴阳的虚损与脱失，分为外因和内因两类，存在偏盛和偏绝的区别。
如邪中于阴，手足厥冷，脉微欲绝，此阴盛而生阳之气欲绝于内也；
如果邪气侵入阴分，导致手足厥冷，脉搏微弱几乎摸不到，这是阴寒过盛，导致体内生发阳气的功能即将衰竭；
如欲冷冻饮料，欲卧凉地，揭去衣被，躁而不安，此阴盛于内而阳欲脱于外也，急宜参、附、姜、桂以救之；
如果出现想喝冰镇饮料、想睡在凉地上、掀开衣服被子、烦躁不安的症状，这是阴寒盛于体内而阳气即将向外脱逸，急需用人参、附子、干姜、肉桂来救治；
如发汗不解，身反大热，此阳盛而阴绝于内也，如阳明病，发热汗多者，急下之，宜大承气汤，此阳盛于内而阴液外脱也。
如果出现发汗后病不愈，身体反而高热，这是阳热过盛而体内阴液枯竭，例如阳明病（阳明经受邪所致的病证），出现发热且出汗多的情况，应当紧急使用泻下法，适宜用大承气汤（大黄、芒硝、厚朴、枳实组成的方剂），这是阳热盛于体内而阴液向外脱失。
若夫内因之阴阳，阳生于阴，阴生于阳。
至于内因导致的阴阳关系，阳气生于阴精，阴精生于阳气。
阳生于阴者，阳气生于阴精也；阴生于阳者，阴精之生于阳化也。
所谓阳气生于阴，是指阳气根源于阴精；所谓阴精生于阳，是指阴精由阳气的蒸腾气化而产生。
阳化者，阳气化水谷之精微，而生此精也。
所谓的阳化，是指阳气将饮食水谷转化为精微物质，从而生成阴精。
阴阳和合，交相生化，是为平人。
阴阳和谐融合，相互化生，这就是健康的人（平人）。
如孤阳不生，独阴不长，此阴阳之生机欲绝于内也。
如果只有孤立的阳气则不能生长，只有单独的阴精则不能发育，这意味着体内的阴阳生机即将断绝。
《难经》曰∶脱阳者见鬼，脱阴者目盲。
《难经》说：阳气脱失的人会看见鬼怪，阴精脱失的人会失明。
盖阳脱者，从下而脱于上；阴脱者，从上而脱于下，故脱阴而目盲者，尚有余命之苟延，脱阳而见鬼者，不计日而死矣。
大概阳气脱失，是从下部根源向上部脱逸；阴精脱失，是从上部官窍向下部根本脱逸。所以阴精脱失导致失明的人，生命还能勉强延续一段时间；阳气脱失导致见鬼的人，不用多少天就会死亡。
夫阳脱之患，多有本于阴虚。
阳气脱失的病症，大多根源于阴精不足。
如年老之人，足膝寒冷，此元阳之气渐衰，而欲绝于下，宜用参附、半硫之类，以助生阳。
例如老年人，脚膝寒冷，这是元气（人体最根本的气）逐渐衰退，阳气在下部即将衰竭，适宜用人参附子丸、半硫丸等药物，来辅助生发阳气。
如或因脾胃虚而谷精不生，或入房甚而肾精日损，或忧恐而藏精渐消，或烦劳而精神日耗，以致阴气日衰，而阳将外脱矣。
或者因为脾胃虚弱导致水谷精微无法生成，或者因为房事过度导致肾精每日损耗，或者因为忧愁恐惧导致脏腑所藏的精华逐渐消散，或者因为烦扰劳累导致精神每日消耗，从而导致阴气日益衰弱，阳气将要向外脱逸。
故治未病者，见阴精有亏，乃阳脱之渐，预培养其阴焉。
所以善于治疗未病（治未病）的医生，看到阴精有亏损，知道这是阳气脱失的前兆，会预先培补阴精。
若待阳气外脱，用桂、附而欲其引火归原，不知阴精者，阳气之生原也，其原已绝，又安所归乎？
如果等到阳气已经向外脱逸，才使用肉桂、附子想要引导浮火回归本源，却不知道阴精是阳气生成的本源，既然本源已经断绝，阳气又能回到哪里呢？
故阳脱而用桂、附救之者，外因之脱也；治内因而用桂、附者，助阳气之衰于下也。（若阴虚而阳脱者，非桂、附可救。）
所以，对于阳气脱失使用肉桂、附子来救治的，是针对外因导致的脱失；针对内因使用肉桂、附子的，是为了帮助下部衰弱的阳气。（如果是阴精亏虚导致的阳气脱失，不是肉桂、附子所能救治的。）
Deficiency and collapse of Yin and Yang are distinguished by external causes and internal causes, and differ in terms of excessive dominance (Pian Sheng) and extreme depletion (Pian Jue).
If pathogenic factors invade the Yin aspect, resulting in cold extremities and a faint pulse nearly imperceptible, this indicates that excessive Yin is causing the Qi generating Yang to be on the verge of exhaustion internally.
If there is a desire for iced beverages, a desire to lie on cool ground, removing clothes and bedding, restlessness and unease, this signifies that Yin Cold is excessive internally while Yang is about to collapse externally; urgent treatment with Renshen (Ginseng Radix et Rhizoma), Fuzi (Aconiti Lateralis Radix Preparata), Ganjiang (Zingiberis Rhizoma), and Guizhi (Cinnamomi Ramulus) is required to rescue the condition.
If sweating fails to resolve the condition and the body becomes feverish instead, this indicates excessive Yang and internal exhaustion of Yin. For instance, in Yangming disease (disease of the Yangming channel), where there is fever and profuse sweating, urgent purgation is indicated, suitable for Dachengqi Tang (Major Order the Qi Decoction); this represents excessive Yang internally and external collapse of Yin fluids. These are cases of Yin-Yang imbalance and extreme depletion due to external causes.
Regarding internal causes of Yin and Yang: Yang is born from Yin, and Yin is born from Yang. "Yang born from Yin" means Yang Qi originates from Yin Essence; "Yin born from Yang" means Yin Essence is generated through the transformational power of Yang. This transformation refers to Yang Qi transforming the essence of food and drink to generate this essence. When Yin and Yang harmonize and mutually generate each other, one is considered a healthy person (Ping Ren). If solitary Yang cannot grow and isolated Yin cannot develop, it indicates that the vital mechanism of Yin and Yang is about to cease internally. The Nan Jing states: "Those whose Yang collapses see ghosts; those whose Yin collapses go blind." Generally, Yang collapse involves departure from the lower part upwards; Yin collapse involves departure from the upper part downwards. Therefore, those who go blind due to Yin collapse may still have their life prolonged slightly, whereas those who see ghosts due to Yang collapse will die within a few days.
The affliction of Yang collapse often stems from Yin deficiency. For example, in elderly people with cold feet and knees, this indicates that Yuan Qi (Primordial Qi) is gradually declining, with Yang about to fail at the lower part; treatments such as Shenfu Wan (Ginseng and Aconite Pill) or Banshu Wan (Half-Sulfur Pill) should be used to assist the generation of Yang. If Spleen and Stomach deficiency leads to failure in producing grain essence, or if excessive sexual activity daily damages Kidney Essence, or if worry and fear gradually deplete stored essence, or if mental toil daily consumes spirit and vitality, leading to daily decline of Yin Qi and impending external collapse of Yang, then practitioners of preventive treatment (Zhi Wei Bing) must recognize that Yin Essence deficiency is the precursor to Yang collapse and preemptively nourish Yin.
If one waits until Yang has already collapsed externally and uses Guizhi and Fuzi hoping to guide fire back to its source, without realizing that Yin Essence is the origin of Yang's generation, once this origin is severed, where can it return? Thus, using Guizhi and Fuzi to rescue Yang collapse applies to collapse due to external causes; using them for internal causes serves to assist declining Yang at the lower part. (Note: In cases of Yin deficiency leading to Yang collapse, Guizhi and Fuzi are not curative.) Hence, it is said that deficiency and collapse of Yin and Yang are distinguished by external and internal causes, and differ in excessive dominance and extreme depletion.