凡霜降以后，春分以前，天气严寒，调理不谨，感中其邪，头疼壮热，名为伤寒。
其余二季，虽寒而不严，何有真伤寒之病也。然冬月严寒，何伤寒多而中寒者少，三
季微寒，何伤寒无而中寒者偏多？盖冬主闭藏，天之阳气，人之阳气，产伏于内，所以
外虽严寒，不能直入，乃名为伤。当从表
散，表罢里和，毋拘三阴传变。若在春夏，天之阳气，人之阳气，升浮在外，加之不
谨，外虽微寒，可以直中阴经，乃名为中，当急温补。即有发热者。乃虚阳浮表也，其
脉必沉细而无神，且补中气以敛虚阳。有头痛者，虚火胃土也，其脉必浮大而无力，宜
温下元，以藏龙火，此引火归源之法，以治假热之症也。更有假胀者，凡人中气充足，
健运不息，何有胀满之虞？若胃虚不能纳食，则有虚饱之患；脾虚不能化谷，则有倒
饱作胀之虞。更有下元虚极，无根脱气，上乘胸火，盖肾主纳气，肺主出气，肾虚不能
闭藏，则气竟出而不纳，肺虽司出，气奔太迫，有出无归，肺亦胀满，是以胸膈之间，
胀闷难状，甚则攻刺冲心，大痛欲绝，此惟宜以补为消，从塞因塞用之法。心脾不足
者，大补心脾，以便中气营运则快。若肾经虚寒者，温补下元，使真气封藏乃愈。此纳
气藏源之法，以治假胀之症也。如不知此，一如消克顺气，益令虚气无根据，上攻喘促而
死。然气病用气药而不效者，缘气之藏者，无以收也。肺主气，肾藏气，故古人用补肾
药加肉桂、五味子，以收浊气下归也。总之，表热多，由里阳外越；上热皆由下火上
乘，虽有外邪感触，亦不过初受发病之端。况玩《经》云∶邪之所奏，其气必虚。可见
外邪感袭，亦由虚名。至于春夏阳气浮越，尤易正气外泄，倘不知此，轻投寒剂，则外
浮挂散之阳，何自而归，内存几杀之阳，复加扑灭，重则暴亡，轻则中满。奈何近医不
识病情，凡五六月发热，概云瘟病，伤寒，稍见红点，即云时行、瘟疹，投以寒凉，误
人多矣。至于口干烦渴，喜冷浩饮，似属实热，然究其源，若非胃汁干枯，即系肾水燥
稿，所以引水自救也。冰水入胃，津液愈凝，寒入丹田，虚火益上，虽系龙雷，亦能
焚焦草木，故画赤眼红，牙焦舌燥，六脉洪数，竟似有余，投以寒凉，必致烦躁狂扰，
津液燥竭而死。若能求源从治，用水中补火，热药凉饮之方。二三剂后，自然假阳之
症潜消，而真寒之症毕露，不知此而以寒凉误人者更多矣，惟真伤寒实热便秘等候者，
则从寒凉利下。先标后本可也。然须辨症的确，务审可寒则寒，可下则下，必期中病，
否则，杀人如剑，慎之！
凡是在霜降之后、春分之前，天气极度寒冷，如果调理不慎，感受了寒邪，出现头痛和高热，这被称为伤寒。
在其余两个季节（指春季和秋季），虽然寒冷但并不严酷，怎么会有真正的伤寒病呢？然而冬天严寒，为什么患伤寒的多而患中寒的少；而在其他三个季节微寒时，为什么没有伤寒却偏多患中寒呢？这是因为冬季主闭藏，天的阳气、人的阳气都潜藏伏于体内，所以虽然外面严寒，寒气不能直接侵入，这才称为“伤”。治疗应当从体表发散，表证解除后里气调和，不要拘泥于三阴经的传变规律。如果在春夏季节，天的阳气、人的阳气升浮在外，加上调理不慎，虽然外面只是微寒，寒气可以直接侵入阴经，这才称为“中”，治疗应当紧急温补。即使有发热的症状，这也是虚阳浮越于体表所致，其脉象必定沉细且无神，应当补益中气以收敛虚阳。如果有头痛的症状，这是虚火因胃土虚弱而上炎所致，其脉象必定浮大但无力，适宜温补下元，以潜藏龙雷之火，这是引火归源的方法，用来治疗假热的病症。更有假胀的情况，凡是人体中气充足，脾胃健运不息，哪里有胀满的担忧呢？如果胃虚不能受纳食物，就会有虚性饱胀的祸患；脾虚不能运化谷物，就会有倒饱作胀的忧虑。更有下元极度虚弱，元气无根欲脱，上乘胸膈之火，盖肾主纳气，肺主出气，肾虚不能闭藏，那么气就只出不纳，肺虽然主管呼气，但气奔涌太急迫，只有出没有归，肺也会胀满，因此在胸膈之间，胀闷难以形容，严重时甚至攻刺冲心，剧烈疼痛几乎要断气，这种情况只宜以补法作为消导法，遵循“塞因塞用”的原则。如果是心脾不足，就大补心脾，使中气营运通畅就会好转。如果是肾经虚寒，就温补下元，使真气封藏才能痊愈。这是纳气归源的方法，用来治疗假胀的病症。如果不了解这些，依然使用消食克伐、顺气的药物，只会让虚气更加无所依托，向上攻冲导致喘促而死。然而气病使用理气药却不生效的原因，是因为气的收藏功能失去了收摄能力。肺主气，肾藏气，所以古人使用补肾药加入肉桂、五味子，来收敛浊气使其下行回归。总之，表热多，是由于里阳外越；上部的热皆由于下焦之火上乘，虽然有外邪感触，也不过是初受发病的开端。况且研读《内经》说：邪气之所以能侵袭，是因为人体的正气必然虚弱。可见外邪感袭，也是由虚证引起的。至于春夏阳气浮越，尤其容易导致正气外泄，如果不知道这一点，轻率投用寒凉药剂，那么外浮涣散的阳气，从哪里回归？体内残存的几近死亡的阳气，又遭到扑灭，重则暴死，轻则中满腹胀。奈何近世的医生不认识病情，凡是五六月发热，一概说是瘟病、伤寒，稍微见到红点，就说时行病、瘟疹，投用寒凉药物，误人太多了。至于口干烦渴，喜欢冷饮，似乎属于实热，然而究其根源，如果不是胃汁干枯，就是肾水燥竭，所以引水自救。冰水进入胃中，津液更加凝结，寒气进入丹田，虚火更加上炎，虽然是龙雷之火，也能焚烧草木，所以出现赤眼红、牙焦舌燥，六脉洪数，竟然看似有余，投用寒凉药物，必定导致烦躁狂乱，津液燥竭而死。如果能追本求源，从本质治疗，用水中补火、热药凉饮的方剂。两三天后，自然的假阳之症潜然消退，而真寒之症完全显露，不知道这一点而用寒凉药物误人的更多了，只有真正的伤寒实热便秘等证候，才从寒凉利下的方法治疗。先治标后治本是可以的。然而必须辨证确切，务必审察可寒则寒，可下则下，必须中病即止，否则，杀人如割剑，一定要谨慎！
From the time after Frost's Descent (Shuangjiang) to before Spring Equinox (Chunfen), when the weather is severely cold, if one fails to regulate life carefully and contracts the pathogenic factor, resulting in headache and high fever, it is named Cold Damage (Shanghan).
In the other two seasons, although it is cold, it is not severe; how can there be a true Cold Damage disease? However, why are there many cases of Cold Damage but few cases of Middle Cold during the severe winter, while in the other three seasons with slight cold, there are no cases of Cold Damage but many cases of Middle Cold? This is because Winter governs closure and storage; the Yang Qi of Heaven and the Yang Qi of humans are hidden within. Therefore, although it is severely cold outside, the pathogen cannot enter directly, which is why it is called "injury" (Shang). Treatment should focus on dispersing from the exterior. Once the exterior syndrome resolves and the interior harmonizes, one should not be constrained by the transmission patterns of the Three Yin meridians. If it occurs in Spring or Summer, the Yang Qi of Heaven and humans ascends and floats outward. Coupled with careless regulation, even slight cold outside can directly penetrate the Yin meridians, which is why it is called "middle" (Zhong). Treatment should urgently employ warming and tonifying methods. Even if there is fever, this is due to deficient Yang floating on the surface; the pulse must be deep, fine, and lacking spirit. One should tonify the Middle Qi to consolidate the deficient Yang. If there is headache, this is due to deficient fire rising from weak Stomach Earth; the pulse must be large and floating but powerless. It is appropriate to warm the Lower Yuan to conceal the Dragon Fire. This is the method of guiding fire back to its source, used to treat symptoms of false heat. Furthermore, there are cases of false distension. Whenever the Middle Qi of a person is sufficient and the Spleen and Stomach transport functions are unceasing, where would there be worry about distension? If the Stomach is deficient and cannot receive food, there will be the hazard of false fullness; if the Spleen is deficient and cannot transform grain, there will be the risk of regurgitation and distension. Moreover, if the Lower Yuan is extremely deficient, with rootless and escaping Qi ascending to the chest fire: since the Kidney governs receiving Qi and the Lung governs expelling Qi, Kidney deficiency fails to close and store, so Qi goes out without being received. Although the Lung manages expulsion, the Qi rushes too urgently, going out without returning, causing the Lung to become distended. Thus, between the chest and diaphragm, there is unbearable distension and oppression, and in severe cases, it attacks and pierces the Heart, causing severe pain almost leading to death. In such cases, only tonification as a method of elimination is suitable, following the principle of "treating obstruction with obstruction" (Sai Yin Sai Yong). For Heart and Spleen insufficiency, greatly tonify the Heart and Spleen so that the Middle Qi circulates smoothly and brings relief. For Kidney Meridian deficiency-cold, warm and tonify the Lower Yuan so that the True Qi is sealed and stored, leading to recovery. This is the method of receiving Qi and storing at the source, used to treat symptoms of false distension. If one does not understand this and continues to use digestive, purgative, or Qi-regulating drugs, it will only make the deficient Qi more unsupported, attacking upward causing panting and death. However, the reason why Qi-regulating drugs fail for Qi disorders is that the storage function of Qi lacks consolidation. The Lung governs Qi, and the Kidney stores Qi. Therefore, ancients used Kidney-tonifying herbs added with Rou Gui (Cinnamon Twig) and Wu Wei Zi (Schisandra Fruit) to collect turbid Qi and guide it downward. In summary, excessive exterior heat is due to Interior Yang escaping outward; upper heat is all due to lower fire ascending. Although there may be external pathogenic contact, it is merely the beginning of the initial onset. Moreover, studying the *Classic* states: "Where the pathogen resides, the Qi must be deficient." This shows that external pathogenic invasion is also caused by deficiency. During Spring and Summer, when Yang Qi floats outward, it is especially easy for Righteous Qi to leak outward. If one does not know this and lightly administers cold-cooling agents, then how will the floating and scattered Yang return? The remaining dying Yang inside will be further extinguished, leading to sudden death in severe cases or middle-fullness in mild cases. Alas, modern physicians do not recognize the condition. Whenever there is fever in the fifth or sixth month, they generally call it Plague Disease or Cold Damage. If slightly red spots appear, they call it seasonal epidemic or plague rash, and administer cold-cooling medicines, misleading many people. As for dry mouth, vexation, thirst, and preference for cold drinks, which seem to be excess heat, investigating the source reveals that either the Stomach fluids are dried up or the Kidney water is parched, thus drawing water to save oneself. Ice water entering the stomach causes body fluids to congeal further; cold entering the Dantian makes deficient fire rise higher. Although it is Dragon-Thunder fire, it can still scorch grass and trees. Hence, red eyes, scorched teeth, and dry tongue appear, and the six pulses are surging and rapid, seemingly indicating excess. Administering cold-cooling medicines will inevitably lead to vexation, mania, and death due to exhaustion of body fluids. If one seeks the source and treats according to the nature, using formulas that tonify fire within water or take hot medicines coolly, after two or three doses, the false Yang symptoms will naturally subside, and the true Cold symptoms will fully emerge. More people are misled by cold-cooling medicines because they do not understand this. Only in cases of true Cold Damage with excess heat and constipation should one follow the method of cold-cooling and purging. Treating the branch first and the root later is acceptable. However, one must distinguish the syndrome accurately, carefully examining whether to use cold or purge. One must hit the disease precisely; otherwise, it kills like a sword. Be cautious!