伤寒、瘟疫，俱外侮之证，惟内实者能拒之，即有所感而邪不胜正，虽病无害。最畏者，
惟内虚之人，正不胜邪，邪必乘虚深入，害莫大矣。故曰伤寒偏打下虚人。且今人虚弱者多
，强实者少，设遇挟虚伤寒，而不知速救根本，则百无一生。故伤寒书曰∶阳证得阴脉者，
死。正以阴脉即虚证也。此欲辨之，惟脉为主，而参以形证，自无失矣。盖凡遇伤寒外热等
证，而脉见微弱浮空，举按无力者，即是虚证，最不易解，最不宜攻。虽欲发汗，汗亦难出
，即有微汗，亦不过强逼肤腠之汗，而必非营卫通达之所化。若罔顾虚实而逼之太甚，则中
气竭而危亡立至矣。
然治虚之法，须察虚实之微甚。若半虚者，必用补为主，而兼散其邪。若太虚者，则全
然不可治邪。而单顾其本，顾本则专以保命，命得不死，则元气必渐复，或于七日之后，或
十四日。甚者二十日之后，元气一胜，邪将不攻自溃，大汗至而解矣。欲知其兆，亦察其脉
，但得弱者渐强。小者，渐大。弦者，渐滑。紧者，渐缓。则大汗将通，吉期近矣。
凡用补之法，但察其胸膈何如。若胸腹多滞者，未可补。年壮气实者未可补。若气本
不实，而胸腹无滞，则放胆用之。又若内无热邪，而素宜用温，其或气有难行者，则必兼暖
胃而后可。盖补得暖而愈行，邪得暖而速散，切不可杂用消耗寒凉，以分温补之力。其或初
感寒邪，但见脉证真虚，邪不易散等证，则人参、熟地之类，开手盒饭速用，愈早愈妙，若
或迟疑，则纵寇深入，反成难制。此治虚邪最善之法也。余用此法，活人多矣。
常闻昧者有伤寒忌补之说，不知补者所以补中，是即托里之意。亦以寒邪如盗，其来在
外，元气如民，其守在中，足民正所以强中，强中正所以御外，保命玄机，惟此一着。何为
补住邪气？庸妄误人，莫此为甚。余因再悉于此，用补伤寒治法之未备，渐用渐熟，方知其
妙。自今而后，知必有不惑余言，而受余之生者，将无穷矣。
一、伤寒精血素弱，或阴中阳气不足，脉细弱而恶寒者，必须大助真阴，则阳从阴出，
而表邪自可速解。惟理阴煎加柴胡、麻黄之类，或随证加减用之为最妙。若伤寒于七日八日
之后，脉数无力，神昏气倦，或躁扰不宁，散之不可，清之不可，而邪不能解者，只宜理阴
煎大剂与之，真回生神剂也。若气血俱虚而邪不能解，只宜平补者，以五福饮为主，而随证
加减用之，或大补元煎，或六物煎，或十全大补汤，皆可用。若脾胃中气虚弱，而邪不能解
者，宜四君子汤加减用之。若中气虚弱脾寒，或兼呕恶而邪不解者，宜五君子煎、温胃饮。
若劳倦伤脾，寒邪内陷，身热不退，当升散者，宜补中益气汤。若寒邪陷入阴分，血虚不能
外达，而当升散者，宜补阴益气煎。若阴虚发热，面赤口渴，烦躁，脉浮洪无力者，宜六
味地黄汤大剂与之，一服可愈。凡中气虚寒，表邪不解，或日久畏药，或诸药不效者，只宜
独参汤，或浓或淡，或冷或热，随其所好，时时代茶与之，连日勿间，使其营气渐复，则邪
气渐退，大有回生之妙，毋勿之也。
一、伤寒用补之法，与用攻用散者不同。盖攻散所以去实邪，其力峻，其效速。故凡用
柴胡、麻黄之类，取效在一二三剂之间，用大黄、芒硝之类，取效在一剂之间，此而不效。
必其用之不善，不可多也。至若用补者，所以补虚，其力柔，其功缓，虽于一二剂见效者，
亦多有之。若积劳积损，气血虚甚者，欲其复元，诚不易也。但察其服补无碍，或于脉证间
略见相投，便是得补之力。故轻者二三剂，重者十余剂，方得见功，而汗出邪退以愈也。若
不知此理，而但于一二剂间，未见速效，则必致庸谗起，惑乱生，而全功尽弃矣。此不可不
深察也。
伤寒和瘟疫，都属于外邪侵袭的病症，只有体内正气充实的人才能抵御它们。即使受到感染，也是邪气不胜正气，虽然生病但不会造成危害。最让人担忧的是，那些体内正气虚弱的人，正气不能战胜邪气，邪气必定会乘虚深入，造成的危害没有比这更大的了。所以说“伤寒病偏重于损伤下焦虚损之人”。况且现在身体虚弱的人多，强壮结实的人少，如果遇到夹杂虚证的伤寒，却不知道迅速挽救根本（元气），那么百人中难有一人生还。所以伤寒医书说：“阳证出现阴脉的，主死。”正是因为阴脉即代表虚证。想要辨别这一点，主要以脉象为主，再参考形体症状，就不会有失误了。大凡遇到伤寒外热等症状，而脉象表现为微弱、浮取空豁，轻按重按都无力的，就是虚证，最难处理，最不宜用攻伐之法。即使想要发汗，汗也难以排出，即便有微汗，也不过是强行逼迫腠理之汗，而并非营卫通达所化生的正常汗液。如果不顾虚实情况而过度逼迫发汗，那么中气就会竭绝，危亡立刻到来。
然而治疗虚证的方法，必须察辨虚损程度的轻重。如果是半虚的情况，必须以补益为主，兼以疏散邪气。如果是非常虚的情况，则完全不可以治疗邪气，而只需专门顾护根本。顾护根本就是专门保命，只要性命保住，元气必然逐渐恢复，或者在七天之后，或者十四天，严重的甚至二十天之后，一旦元气胜复，邪气将不攻自破，大汗出而病解。想要知道这种征兆，也要观察脉象，只要见到弱的脉象逐渐变强，小的脉象逐渐变大，弦的脉象逐渐变滑，紧的脉象逐渐变缓，那么大汗即将通畅，痊愈的日子就近了。
凡是使用补法，只须察辨胸膈的情况。如果胸腹部多有痞滞的，不可进补。年轻体壮、气血实盛的，不可进补。如果原本气就不实，且胸腹部无痞滞，则可以大胆使用。另外，如果体内没有热邪，且素来适宜用温药，或者气机运行不畅的，则必须兼用暖胃药之后才可以进补。因为补药得温热之气则运行更畅，邪气得温热之气则消散更快，切不可混杂使用消耗正气的寒凉药物，以免分散温补的力量。如果初感寒邪，只见脉证真正属于虚证，邪气不易散除等情况，那么人参、熟地黄之类的药物，开始治疗时就应该迅速使用，越早越好。如果犹豫迟疑，就会让寇贼（邪气）深入，反而难以控制。这是治疗虚邪最好的方法。我使用这种方法，救活的人很多。
常听说庸医有“伤寒忌用补法”的说法，他们不知道补法是用来补益中气的，这就是托里透脓的意思。也将寒邪比作盗贼，它来自外部；将元气比作百姓，它守卫在内部。充足百姓正是为了强大内部，强大内部正是为了抵御外部，保全性命的玄机，就在于这一着。怎么能说是把邪气补住了呢？庸俗狂妄之人误导人，没有比这更严重的了。我因此详细阐述于此，用以补充伤寒治法中关于补法的不足，随着使用越来越熟练，才知道其中的奥妙。从今以后，相信一定会有不被我的言论迷惑，而接受我的救治得以生存的人，将是无穷无尽的。
一、伤寒患者如果精血素来虚弱，或者阴中阳气不足，脉象细弱且恶寒的，必须大力助益真阴，这样阳气就能从阴中生发出来，表邪自然可以迅速解除。用理阴煎加入柴胡、麻黄之类，或者随证加减使用最为巧妙。如果伤寒到了七八日之后，脉数而无力，神志昏沉气息疲倦，或者烦躁不安，既不能用发散法，也不能用清热法，而邪气不能解除的，只宜用大剂量的理阴煎给予服用，真是起死回生的神效方剂。如果气血都虚弱而邪气不能解除，只宜平补的，以五福饮为主方，随证加减使用，或者大补元煎，或者六物煎，或者十全大补汤，都可以使用。如果脾胃中气虚弱，而邪气不能解除的，宜用四君子汤加减使用。如果中气虚弱脾寒，或者兼有呕吐恶心而邪气不解的，宜用五君子煎、温胃饮。如果因劳倦损伤脾气，寒邪内陷，身热不退，应当升散邪气的，宜用补中益气汤。如果寒邪陷入阴分，血虚不能外达，而应当升散邪气的，宜用补阴益气煎。如果阴虚发热，面红口渴，烦躁，脉浮洪但无力的，宜用大剂量六味地黄汤给予服用，一服即可痊愈。凡是中气虚寒，表邪不解，或者日久畏惧服药，或者各种药物无效的，只宜用独参汤，无论浓淡冷热，随病人喜好，时时代替茶水饮用，连续几天不间断，使其营气逐渐恢复，则邪气逐渐退去，大有起死回生的奇妙功效，不要忽视它。
一、伤寒使用补法，与使用攻法和散法不同。攻法和散法是为了去除实邪，药力峻猛，见效迅速。所以凡是使用柴胡、麻黄之类，疗效在一两三个疗程之间取得；使用大黄、芒硝之类，疗效在一个疗程之间取得，这些如果无效，一定是使用方法不当，不可多用。至于使用补法，是为了补益虚损，药力柔和，功效缓慢，虽然也有在一两个疗程见效的，但大多如此。如果是积劳积损，气血极度虚弱的，想要恢复元气，确实不容易。只要察验其服用补药没有阻碍，或者在脉证之间略微看到相契合的迹象，就是得到了补药的力量。所以轻症一二个疗程，重症十余个疗程，才能见效，出汗邪退而痊愈。如果不懂这个道理，仅仅在一两个疗程间，没见到速效，就一定会导致庸医谗言兴起，惑乱产生，从而前功尽弃。这是不可不深刻考察的。
Typhoid fever (Shanghan) and plague (Wenyi) are both conditions caused by external pathogenic invasions. Only those with sufficient internal righteous Qi (Zhengqi, the body's resistance to disease) can repel them. Even if infection occurs, since pathogens cannot overcome righteous Qi, although illness ensues, it causes no harm. The most feared scenario involves individuals with deficient internal righteous Qi, where righteous Qi fails to overcome pathogens, allowing pathogens to penetrate deeply due to deficiency, causing immense harm. Hence it is said: "Typhoid fever tends to injure those with lower jiao deficiency." Moreover, nowadays many people are weak, while few are strong and robust. If one encounters typhoid fever complicated by deficiency and fails to rapidly rescue the root (Yuanqi, primordial qi), survival rates would be extremely low. Thus, texts on typhoid state: "Yang syndromes presenting with Yin pulses indicate death." This is because Yin pulses signify deficiency. To distinguish this, pulse diagnosis is primary, supplemented by physical signs and symptoms, ensuring accuracy. Generally, when encountering external heat symptoms of typhoid, if the pulse appears weak, floating and empty, and powerless upon both light and heavy pressure, it indicates a deficiency syndrome. This is difficult to manage and absolutely contraindicates purgative or attacking methods. Even if sweating is desired, sweat will be hard to produce. Any slight sweat produced would merely be forced out from the skin pores (Couli) through coercion, not generated by the smooth circulation of Ying (Nutritive) and Wei (Defensive) Qi. Ignoring deficiency versus excess and coercing sweating too severely will lead to exhaustion of Middle Qi (Zhongqi, spleen and stomach qi), resulting in immediate peril.
However, treating deficiency requires assessing the severity of the deficiency. In cases of moderate deficiency, tonification should be the main approach, combined with dispersing pathogens. In cases of severe deficiency, treating the pathogen is entirely inappropriate; instead, focus solely on protecting the root. Protecting the root means preserving life; once life is preserved, Yuanqi will gradually recover, either after seven days, fourteen days, or even twenty days in severe cases. Once Yuanqi prevails, pathogens will collapse without direct attack, leading to resolution through profuse sweating. To recognize this sign, observe the pulse: if a weak pulse becomes stronger, a small pulse becomes larger, a wiry pulse becomes slippery, and a tight pulse becomes relaxed, it indicates that profuse sweating is about to occur, signaling impending recovery.
When employing tonification, examine the chest and diaphragm. If there is stagnation in the chest and abdomen, tonification is contraindicated. Young individuals with robust Qi and blood should not be tonified. If Qi is inherently deficient but there is no stagnation in the chest and abdomen, tonification may be used boldly. Furthermore, if there is no internal heat pathogen and the patient generally responds well to warming herbs, or if Qi movement is obstructed, warming the Stomach (Wei) must be added before tonifying. Tonics act more effectively when warmed, and pathogens dissipate faster with warmth. It is crucial not to mix in cooling herbs that consume Qi, as this would dilute the warming and tonifying power. If initially exposed to cold pathogens, and true deficiency signs are present with difficulty in dispersing pathogens, herbs like Ren Shen (Ginseng Root) and Shu Di Huang (Prepared Rehmannia Root) should be used immediately at the start of treatment; earlier is better. Hesitation allows pathogens to deepen their invasion, becoming harder to control. This is the optimal method for treating deficiency-type pathogens. I have saved many lives using this method.
It is often heard that ignorant practitioners claim "tonification is contraindicated in typhoid." They fail to understand that tonification supports the Middle Jiao (Zhongjiao, digestive system), which is equivalent to supporting the interior. Just as cold pathogens are like thieves coming from outside, and Yuanqi is like citizens guarding the inside, strengthening the citizens strengthens the interior, which in turn defends against the exterior. The secret to preserving life lies in this strategy. How could tonification trap pathogens? Such absurd errors mislead people gravely. I elaborate here to supplement the incomplete discussion on tonification in typhoid treatments. As practice increases, its efficacy becomes apparent. From now on, many will undoubtedly benefit from my advice and survive.
1. For typhoid patients with inherent essence and blood deficiency, or insufficient Yang within Yin, presenting with fine, weak pulses and aversion to cold, it is essential to strongly assist True Yin (Zhenyin). This allows Yang to emerge from Yin, enabling rapid resolution of exterior pathogens. Li Yin Jian (Cinnamon Twig and Rehmannia Decoction) added with Chai Hu (Bupleurum Root) and Ma Huang (Ephedra Herb), or modified according to symptoms, is most effective. If, after seven or eight days of typhoid, the pulse is rapid yet powerless, accompanied by mental confusion, fatigue, or restlessness, and neither dispersing nor clearing methods work, large doses of Li Yin Jian should be administered. It is a miraculous formula for restoring life. If both Qi and Blood are deficient and pathogens persist, mild tonification is indicated, primarily using Wu Fu Yin (Five Blessings Decoction), modified as needed. Da Bu Yuan Jian (Great Tonify Origin Decoction), Liu Wu Jian (Six Ingredients Decoction), or Shi Quan Da Bu Tang (Comprehensive Great Tonifying Decoction) are also applicable. If Spleen-Stomach Middle Qi is weak with persistent pathogens, Si Jun Zi Tang (Four Gentlemen Decoction) modified is suitable. If Middle Qi deficiency involves Spleen Cold, or is accompanied by vomiting/nausea, Wu Jun Zi Jian (Five Gentlemen Decoction) or Wen Wei Yin (Warm Stomach Drink) should be used. If labor and fatigue damage the Spleen, causing cold pathogens to sink inward with persistent fever requiring ascending dispersion, Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction) is appropriate. If cold pathogens sink into the Yin aspect, with Blood deficiency preventing outward expression requiring ascending dispersion, Bu Yin Yi Qi Jian (Tonify Yin and Augment Qi Decoction) is indicated. For Yin deficiency with fever, red face, thirst, irritability, and a floating, surging yet powerless pulse, large doses of Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia) should be given, often curing after one dose. For Middle Qi deficiency-cold with unresolved exterior pathogens, or long-term medication aversion, or ineffectiveness of other drugs, Du Shen Tang (Single Ginseng Decoction) is recommended. Regardless of concentration or temperature, it can be taken frequently like tea, day after day without interruption, allowing Ying Qi to gradually recover and pathogens to recede. This has great curative power; do not neglect it.
2. The use of tonification in typhoid differs from purgative or dispersing methods. Purgatives and dispersants remove excess pathogens; their action is potent and rapid. For instance, Chai Hu and Ma Huang typically show effects within two to three doses; Da Huang (Rhubarb Root) and Mang Xiao (Mirabilite) within one dose. Failure in these cases usually stems from improper usage, not overuse. Conversely, tonification addresses deficiency; its action is gentle and slow. Although some see results in one or two doses, it is common for chronic depletion of Qi and Blood to require prolonged treatment for recovery. Observe whether the patient tolerates tonification or if pulse/symptoms show slight improvement; this indicates the tonic is taking effect. Mild cases may take two to three doses; severe cases may require ten-plus doses before sweating occurs, pathogens retreat, and recovery happens. Without understanding this, expecting rapid results in one or two doses leads to doubt, interference from quacks, and abandonment of therapy. This principle must be deeply understood.