夫补者所以补中，何以亦能散表？盖阳虚者，即气虚也，气虚于中，安能达表，非补其气，肌
能解乎？凡脉之微弱无力，或两寸短小而多寒者，即其证也，此阳虚伤寒也。阴虚者，即血虚也，
血虚于里，安能化液，非补其精，汗能生乎？凡脉之浮芤不实，或两尺无根而多热者，即其证也，
此阴虚伤寒也。然补则补矣，仍当酌其剂量，譬之饮酒者，能饮一勺，而与一升，宜乎其至于困也；
使能饮一斗，而与一合，其真蚍蜉之撼大树耳。
夫寒中者所以清火，何以亦能散表？盖阳亢阴衰者，即水亏火盛也，水涸于经，安能作汗？譬
之干锅赤裂，润自何来？但加以水，则郁蒸沛然，而气化四达。夫汗自水生，亦犹是也，如前论言
补阳补阴者，宜助精气也；
此论言以水济火者，宜用寒凉也。盖补者，补中之不足；济者，制火之有余，凡此均能解表，
其功若一，而宜寒宜暖，其用不侔，是有不可不辨。
伤寒者，危病也。治伤寒者，难事也。所以难者，亦惟其理有不明，而不得其要耳。所谓要者
，亦惟正气、
邪气二者之辨而已，使能知正气之虚实，邪气之浅深，则尽之矣。夫寒邪外感，无非由表而入里，
由表而入者，亦必由表而出之，故凡患伤寒者，必须得汗而后解。但正胜邪者，邪入必浅，此元气
之强者也。邪胜正者，其入必深，此元气之弱者也。邪有浅深，则表散有异，正有虚实，则攻补有
异，此三表之法所不容不道也。何为三表？盖邪浅者，逐之于藩篱，散在皮毛也；渐深者，逐之于
户牖，散在筋骨也；深入者，逐之于堂室，散在脏腑也。故浅而实者宜直散，直散者，直逐之无难
也。虚而深者宜托散，托散者，但强其主，而邪无不散也，今姑举其略∶如麻黄汤、桂枝汤、参苏
饮、羌活汤、麻桂饮之类，皆单逐外邪，肌表之散剂也。又如小柴胡汤、补中益气汤、三柴胡饮、
四柴胡饮之类，皆兼顾邪正，经络之散剂也。再如理阴煎、大温中饮、六味回阳饮、十全大补汤之
类，皆建中逐邪，脏腑之散剂也。呜呼！以散药而散于肌表经络者，谁不知之，惟散于脏腑则知者
少矣。以散为散者，谁不知之，惟不散之散，则玄之又玄矣。余因古人之未及，故特吐其散邪之精
义有如此。
补益法本用于补益中气，为什么也能发散表邪？这是因为阳虚就是气虚，中焦气虚，怎么能通达体表呢？如果不补益其气，肌表怎么能够解表发汗呢？凡是脉象微弱无力，或者两寸脉短小且伴有寒象的，就是这种证候，这属于阳虚伤寒。阴虚就是血虚，里阴血虚，怎么能化生津液呢？如果不补益其精血，汗液怎么能够产生呢？凡是脉象浮大而中空不实，或者两尺脉无根且伴有热象的，就是这种证候，这属于阴虚伤寒。然而，虽然说是补益，但仍应当斟酌剂量。这就好比喝酒的人，如果只能喝一杯却给他一升，他自然会醉倒；如果他能喝一斗却只给他一杯，那就像蚂蚁去摇动大树一样徒劳无功。
所谓“寒中”法本是用来清泻内火的，为什么也能发散表邪？这是因为阳亢阴衰，也就是水亏火盛。肾水枯竭于经络，怎么能化作汗液呢？这就好比干锅烧得赤红开裂，滋润从何而来？只要加上水，郁热蒸腾沛然兴起，气化功能就能通达四方。汗液本来也是从津液中化生的，道理也是如此。如前文论述补阳补阴时所说，应该助益精气；这里论述以水济火时所说，应该使用寒凉药物。所谓“补”，是补益中气的不足；所谓“济”，是制约火势的有余。凡此种种都能解表，功效似乎相同，但宜用寒药还是暖药，其应用却不尽相同，这是不可不辨别的。
伤寒是一种危重的疾病。治疗伤寒是一件难事。之所以难，也只是因为医理不明，不得要领罢了。所谓的要领，也不过是辨别正气和邪气这两者而已。如果能知道正气的虚实、邪气的浅深，就掌握关键了。寒邪外感，无非是由表入里，由表而入的，也必然由表而出。所以凡是患伤寒的人，必须通过出汗才能解除病邪。但是正气胜邪气的，邪气侵入必浅，这是元气强盛的表现。邪气胜正气的，侵入必深，这是元气虚弱的表现。邪气有浅深之分，则发散方法就有不同；正气有虚实之别，则攻补策略就有差异。这就是三表法不容不阐述的原因。什么是三表法？邪气浅的，是在藩篱皮毛之间驱逐它，使其散在皮毛；邪气渐深的，是在户牖筋骨之间驱逐它，使其散在筋骨；邪气深入的，是在堂室脏腑之间驱逐它，使其散在脏腑。所以邪气浅而正气实的，适宜直接发散，直接发散就是直接驱逐，没有什么困难。正气虚而邪气深的，适宜托散，托散就是强健主体（正气），那么邪气没有不散去的。现在姑且列举其概要：如麻黄汤、桂枝汤、参苏饮、羌活汤、麻桂饮之类，都是单纯驱逐外邪，属于肌表层面的发散剂。又如小柴胡汤、补中益气汤、三柴胡饮、四柴胡饮之类，都是兼顾邪正双方，属于经络层面的发散剂。再如理阴煎、大温中饮、六味回阳饮、十全大补汤之类，都是建立中气以驱逐邪气，属于脏腑层面的发散剂。唉！用发散药来发散肌表经络之邪，谁不知道？唯独用发散药来发散脏腑之邪，知道的就少了。用发散法来发散邪气，谁不知道？唯独用“不散之散”的方法，那就玄妙又玄妙了。我因为古人未曾提及这些，所以特意阐明发散邪气的精义就是这样。
Tonification is intended to tonify the middle jiao; how can it also release the exterior? This is because Yang deficiency is Qi deficiency. If Qi is deficient in the interior, how can it reach the exterior? Without tonifying its Qi, how can the muscle layer resolve the pathogen? Whenever the pulse is weak and forceless, or both Cun (inch) positions are short with frequent cold signs, this indicates the syndrome, which is Taiyang Cold Damage due to Yang deficiency (Yang Deficiency Cold Damage). Yin deficiency is Blood deficiency. If Blood is deficient in the interior, how can it transform into fluids? Without tonifying its Essence, how can sweat be generated? Whenever the pulse is floating, hollow, and not solid, or both Chi (cubit) positions lack root with frequent heat signs, this indicates the syndrome, which is Taiyang Cold Damage due to Yin deficiency (Yin Deficiency Cold Damage). However, although it is tonification, one must still consider the dosage. It is like a person who can drink one cup being given one sheng (a unit of volume); they will inevitably become intoxicated. Conversely, if someone who can drink one dou (a larger unit) is given only one ge (a small unit), it is like an ant trying to shake a large tree—futile.
The method of "Cold in the Middle" is used to clear fire; how can it also release the exterior? This is because Hyperactive Yang and Declining Yin refers to Water deficiency and Fire excess. When Water is dried up in the channels, how can sweat be produced? It is like a dry pot cracking from intense heat; where would moisture come from? Only by adding water can the stagnation evaporate vigorously, allowing Qi transformation to reach all directions. Sweat originates from fluids, following the same principle. As discussed earlier regarding tonifying Yang and Yin, one should assist Essence and Qi; here, regarding using Water to balance Fire, one should use Cold-Cooling herbs. Tonification addresses the insufficiency within the middle; balancing (Ji) controls the excess of Fire. All these methods can release the exterior, their efficacy seeming similar, yet whether to use Cold or Warm agents differs significantly in application, a distinction that must not be overlooked.
Cold Damage is a critical illness. Treating Cold Damage is difficult. The difficulty lies solely in unclear principles and failing to grasp the key. The key lies merely in distinguishing between Righteous Qi (Zheng Qi) and Pathogenic Qi (Xie Qi). If one knows the deficiency or excess of Righteous Qi and the depth or shallowness of Pathogenic Qi, the essence is mastered. External contraction of Cold pathogens always enters from the exterior into the interior. What enters from the exterior must exit via the exterior. Therefore, patients with Cold Damage must achieve sweating to resolve the disease. However, when Righteous Qi overcomes Pathogenic Qi, the invasion is shallow, indicating strong Yuan Qi (Primal Qi). When Pathogenic Qi overcomes Righteous Qi, the invasion is deep, indicating weak Yuan Qi. Since pathogens vary in depth, dispersal methods differ; since Righteous Qi varies in deficiency or excess, attack and tonification strategies differ. This explains why the Three Methods of Exterior Release (San Biao Fa) must be discussed. What are the Three Methods? Shallow pathogens are expelled from the fence and skin-hair layer; gradually deeper pathogens are expelled from the door/window layer (muscles and sinews/bones); deeply invading pathogens are expelled from the hall/chamber layer (zang-fu organs). Thus, for shallow and solid conditions, direct dispersal is suitable, meaning direct expulsion without difficulty. For deficient and deep conditions, supportive dispersal is suitable, meaning strengthening the host so that pathogens disperse naturally. Brief examples include: Mahuang Tang (Ephedra Decoction), Guizhi Tang (Cinnamon Twig Decoction), Rensu Yin (Ginseng and Perilla Drink), Qianghuo Tang (Notopterygium Decoction), and Magui Yin (Ephedra and Cinnamon Drink)—these purely expel external pathogens and are dispersants for the muscle-skin layer. Examples such as Xiaochaihu Tang (Minor Bupleurum Decoction), Buzhong Yiqi Tang (Tonify the Middle and Augment Qi Decoction), San Chaihu Yin (Three Bupleurum Drink), and Si Chaihu Yin (Four Bupleurum Drink)—these consider both pathogen and Righteous Qi and are dispersants for the meridians. Examples such as Liyin Jian (Regulate Yin Decoction), Dawenzhong Yin (Greatly Warm the Middle Decoction), Liuwei Huiyang Yin (Six-Ingredient Return Yang Drink), and Shiquan Dabu Tang (Ten Complete Great Tonification Decoction)—these establish the middle and expel pathogens, serving as dispersants for the zang-fu organs. Alas! Using dispersing herbs to disperse muscle-skin and meridian pathogens is widely known; few know how to disperse zang-fu pathogens. Using dispersal methods to disperse pathogens is common knowledge; but using "dispersal through non-dispersal" is profound and mysterious. Because ancients did not cover this, I specifically elucidate the refined essence of dispersing pathogens as follows.