仲景云。阴盛阳虚。汗之则愈。下之则死者。此言邪气在表之时也。夫寒邪属阴。身之外者属
阳。且夫各脏腑之经络。亦属阳也。盖阳气为卫。卫气者所以温分肉。充皮毛。肥腠理。司开阖。
此皆卫外而为固也。或烦劳过度。阳气外损。不能卫固。阳为之虚。阳虚者阴必凑之。故阴得以胜。
邪气胜则实。阴盛阳虚者此也。阴邪既盛。腠理致密。阳气伏郁。不得通畅。所以发热恶寒。头
项痛。腰脊强。应解散而药用麻黄者。本草云。轻可去实。葛根、麻黄之属是也。盖麻黄能退寒邪。
使阳气伸越。作汗而解。故曰阴盛阳虚。汗之则愈。里气和平而反下之。中气既虚。表邪乘虚而入
。由是变证百出。故曰下之则死。外台秘要云。表病里和。汗之则愈。下之则死。正此意也。
仲景云。阳盛阴虚。下之则愈。汗之则死者。此言邪气在里之时也。夫寒邪始伤于表。不解而
渐传入于里。变而为热。人之身在里者为阴。华佗云。一日在皮。二日在肤。三日在肌。四日在胸。
五日在腹。六日在胃。入胃谓之入腑也。腑之为言聚也。若府库而聚物焉。又为水谷之海、荣卫之
源。邪气入于胃而不复传流水谷。水谷不消去。郁而为实也。此阳盛阴虚者此也。故潮热引饮。腹
满而喘。手足 汗出。大便难而谵语。宜大承气汤下之则愈。潮热者为实也。此外已解。可攻其
里。而反汗之。表无阴邪。汗又助阳。阳实而又补。
表里俱热。不死何待、外台秘要云。表和里病。下之则愈。汗之则死。正此意也。
张仲景说：阴气盛而阳气虚，发汗治疗则痊愈，攻下治疗则导致死亡。这是指邪气在体表的时候。寒邪属于阴类，人体外部属阳。而且各脏腑的经络，也属于阳的范畴。阳气作为卫气，卫气的作用是温养肌肉、充实皮毛、肥厚腠理、主管毛孔的开合。这些都是护卫体表并使其坚固的功能。如果烦劳过度，导致阳气在外受损，不能固护体表，阳气就会虚弱。阳气虚弱时，阴邪必定侵袭，所以阴得以亢盛。邪气亢盛则为实证，这就是阴盛阳虚的情况。阴邪既已亢盛，腠理致密，阳气伏郁其中，不得通畅，因此出现发热、恶寒、头项疼痛、腰脊强直等症状。应当使用解散表邪的药物，如麻黄。本草记载：“轻清之药可以去实”，葛根、麻黄就属于此类。麻黄能驱退寒邪，使阳气伸展透发，通过出汗而病解。所以说，阴盛阳虚，发汗则愈。如果在里气平和的情况下反而使用攻下法，中气已经虚弱，表邪便会乘虚内陷。由此产生各种变证，所以说攻下则死。《外台秘要》说：表有病而里气和，发汗则愈，攻下则死。正是这个意思。
张仲景说：阳气盛而阴虚，攻下治疗则痊愈，发汗治疗则导致死亡。这是指邪气在体内的時候。寒邪起初损伤体表，若不解散而逐渐传入体内，变化为热邪。人体内部属阴。华佗说：第一天邪气在皮，第二天在肤，第三天在肌，第四天在胸，第五天在腹，第六天在胃。进入胃称为进入腑。腑的意思是聚集，就像府库一样聚集物品。胃又是水谷的海洋、营卫的来源。邪气进入胃中而不继续传化水谷，水谷停滞不消，郁结而成实证。这就是阳盛阴虚的情况。因此出现潮热、引饮（口渴多饮）、腹部胀满且喘促、手足出汗、大便困难且胡言乱语（谵语）。适宜用大承气汤攻下则愈。潮热是实证的表现。此时表邪已解，可以攻逐里实。如果反而使用发汗法，表无阴邪，发汗又会助长阳气，使阳实更甚。导致表里俱热，不死还等什么？《外台秘要》说：表和而里有病，攻下则愈，发汗则死。正是这个意思。
Zhang Zhongjing stated: "When Yin is excessive and Yang is deficient, diaphoresis (sweating) leads to recovery, whereas purgation leads to death." This refers to the situation when pathogenic factors are at the exterior. Cold pathogen belongs to Yin, while the exterior of the body belongs to Yang. Furthermore, the meridians and collaterals of each Zang-Fu organ also belong to Yang. Yang Qi acts as Wei Qi (Defensive Qi), which functions to warm the flesh, fill the skin and hair, thicken the interstices (Couli), and control the opening and closing of pores. These functions all serve to protect the exterior and maintain solidity. If overexertion causes damage to Yang Qi at the exterior, it fails to defend and consolidate, leading to Yang deficiency. When Yang is deficient, Yin pathogens inevitably encroach, allowing Yin to become excessive. Pathogenic excess constitutes a Shi (Excess) syndrome; this is what is meant by "Yin excess and Yang deficiency." Once Yin pathogens are excessive, the interstices become dense, causing Yang Qi to be trapped and stagnant without smooth circulation. Consequently, fever, aversion to cold, pain in the head and nape, and stiffness of the waist and spine occur. Treatment should involve dispersing the exterior using herbs like Mahuang (Ephedrae Herba). Materia Medica states: "Light substances can dispel excess," with Gegen (Puerariae Lobatae Radix) and Mahuang being examples. Mahuang can expel cold pathogens, allowing Yang Qi to extend and emerge, resolving the disease through sweating. Hence, "In cases of Yin excess and Yang deficiency, diaphoresis leads to recovery." If purgation is used when the interior Qi is peaceful, the Middle Qi becomes deficient, and exterior pathogens enter due to this deficiency, giving rise to myriad complications. Thus, "purgation leads to death." The *Waitai Miyao* states: "When there is exterior pathology but the interior is harmonious, diaphoresis leads to recovery, whereas purgation leads to death." This aligns precisely with this meaning.
Zhang Zhongjing stated: "When Yang is excessive and Yin is deficient, purgation leads to recovery, whereas diaphoresis leads to death." This refers to the situation when pathogenic factors are at the interior. Cold pathogens initially injure the exterior; if not resolved, they gradually transmit inward, transforming into heat pathogens. The interior of the human body belongs to Yin. Hua Tuo said: On the first day, the pathogen is in the skin; on the second day, in the flesh; on the third day, in the muscles; on the fourth day, in the chest; on the fifth day, in the abdomen; on the sixth day, in the Stomach. Entering the Stomach is considered entering the Fu organs. The term "Fu" implies gathering, similar to a treasury storing goods. The Stomach is also the sea of water and grain, and the source of Ying (Nutritive) and Wei (Defensive) Qi. When pathogens enter the Stomach and fail to further transform and transport water and grain, the food stagnates and does not digest, becoming constrained and forming an Excess condition. This is what is meant by "Yang excess and Yin deficiency." Therefore, tidal fever, intense thirst, abdominal fullness with panting, sweating of the hands and feet, difficulty in defecation, and delirium occur. Da Chengqi Tang (Major Order the Qi Decoction) should be used for purgation to achieve recovery. Tidal fever indicates an Excess condition. At this stage, the exterior has been resolved, and the interior excess can be attacked. If diaphoresis is used instead, since there is no Yin pathogen at the exterior, sweating will further assist Yang, exacerbating Yang excess. This results in heat in both the interior and exterior; how could one not die? The *Waitai Miyao* states: "When the exterior is harmonious but the interior is pathological, purgation leads to recovery, whereas diaphoresis leads to death." This aligns precisely with this meaning.