一辨其气之异。风主疏泄，寒主凝涩，二气虽有不同，然初皆冷而不热，其中人也，郁而不宣，方其初受在表，自
宜温散。麻黄汤、桂枝汤、葛根汤、苏羌饮等方，皆散寒之剂，非解热之剂也。温热由伏气而成，热而不冷，其伤人也，
立蒸而腐败，初起即宜凉解。栀豉汤（山栀、淡豆豉）、葛根芩连汤（葛根、黄芩、川连、炙草）、麻杏石甘膏（麻黄、
杏仁、生石膏、炙草）、黄芩汤、葳蕤汤（玉竹参、麻黄、杏仁、川芎、青木香、白薇、独活、炙草）、六神通解散（麻
黄、生石膏、苍术、黄芩、滑石、甘草、淡豆豉、葱白）等方，皆解热之剂，非散寒之剂也。以解热之剂治风寒，轻则
寒中呕利；重则阳陷厥逆。以散寒之剂治温热，轻则衄渴谵妄；重则枯竭亡阴。此气之不可不辨也。
二辨其受之异。风寒从表入里，自皮毛而肌腠，而筋骨，而胸膈胃肠，一层渐深一层，不能越此入彼，故汗不厌早，
下不厌迟。为散为和，浅深毫不可紊。以其气皆属冷，必待寒化为热，邪敛入内，方可攻下凉解，否则虚其里气，反引
表邪内陷，而成结胸痞利诸症。湿温从膜原而发，温热从血络而发，先踞膜络之中，必内溃而后变九传，由里出表虽出
表而里未必全无邪恋，经过之半表，亦未必不为邪伤，故下不厌早，汗不厌迟。为和为解，浅深必不可拘。以其气皆属
热，热能作蒸，不必郁变，而此蒸即带彼热，未出表而误温之，始则引热毒燎原，而为斑衄狂喘，末传则伤真阴，为枯
槁沉昏厥逆诸危候矣。
三辨其传经之异。温热传经，与风寒不同。风寒从表入里，故必从太阳而阳明，而少阳，而入胃；若温热则邪从中
道，而或表或里，惟视人何经之强弱为传变。故伏邪之发，有先表后里者，有先里后表者，有但里不表者，有表而再表
者，有里而再里者，有表里偏胜者，有表里分传者，有表里分传而再分传者，有表里三焦齐发者，此谓九传。医必先明
九传之理由，而后能治伏邪。试言其要，风寒从表入里，必待渐次闭郁而传变，故在表时不必兼见里症，入里后不必复
见表症；温热本从里出表，故见表症时，未有不兼见一二里症者，亦未有不兼见一二半表半里症者。且温热属蒸气，表
而里，里而表，原是不常。有里症下之而其邪不尽，仍可出表者；有谵妄昏沉之后，病愈数日，复见头痛发热，复从汗
解者，此所谓表而再表，风寒必无是也。更有下症全具，用下药后，里气通而表亦达，头痛发热得汗而解，胸闷心烦暂
从疹斑而解，移时复见舌黑心闷，腹痛谵妄，仍待大下而后愈者，此所谓里而再里，风寒必无是也。若夫表里分传，三
焦齐发之症，风寒十无一二，温热十有六七，但据传经之专杂为辨。初起专见一经症者属风寒，初起杂见二三经症者属
温热；日久而渐传者属风寒，一日骤传一二经，或二三经者属温热。则虽病有变态，而风寒不混于温热，温热不混于风
寒，施治自无误矣。
一、辨别其病气的不同。风邪主疏泄，寒邪主凝滞涩结，这两种气虽然不同，但初起时都是冷而不热的。当它们侵入人体时，会导致气机郁闭而不能宣发，所以在刚受邪在表阶段，自然适宜用温散的方法治疗。麻黄汤、桂枝汤、葛根汤、苏羌饮等方剂，都是发散寒邪的药剂，而不是清热解热的药剂。温热病是由伏邪（潜伏体内的病邪）化热而成，性质是热而不冷，它伤害人体时，立刻产生蒸腾腐败之象，所以初起时就应当用清凉解表的方法治疗。栀豉汤（由山栀、淡豆豉组成）、葛根芩连汤（由葛根、黄芩、川连、炙甘草组成）、麻杏石甘膏（由麻黄、杏仁、生石膏、炙甘草组成）、黄芩汤、葳蕤汤（由玉竹参、麻黄、杏仁、川芎、青木香、白薇、独活、炙甘草组成）、六神通解散（由麻黄、生石膏、苍术、黄芩、滑石、甘草、淡豆豉、葱白组成）等方剂，都是清热解热的药剂，而不是发散寒邪的药剂。如果用清热解热的药剂去治疗风寒病，轻则导致寒邪伤中引起呕吐腹泻；重则导致阳气下陷、四肢厥逆。如果用发散寒邪的药剂去治疗温热病，轻则导致鼻衄、口渴、胡言乱语、神志狂妄；重则导致阴液枯竭、亡阴危候。这就是病气不可不加以辨别的道理。
二、辨别其受邪途径的不同。风寒之邪从体表进入体内，依次经过皮毛、肌腠、筋骨、胸膈、胃肠，一层层逐渐深入，不能跨越这一层直接侵入下一层，所以发汗不宜过晚，攻下不宜过早。无论是使用发散法还是和解法，深浅层次绝不能紊乱。因为风寒之气都属于冷性，必须等待寒邪转化为热邪，邪气收敛入内之后，才可以采用攻下和凉解的方法，否则会使里气虚弱，反而引发表邪内陷，从而形成结胸、痞满、下利等各种病症。湿温病从膜原发出，温热病从血络发出，先占据膜原和血络之中，必须内部溃败后才会发生九种传变。虽然是从里出表，但即使到了表证阶段，里部未必完全没有残留的邪气，经过的半表半里部位，也未必不被邪气所伤，所以攻下不宜过早（此处原文“下不厌早”与上文风寒“下不厌迟”对应，意指温热病邪易内陷或化热迅速，需及时清里，或指根据病情灵活掌握，但结合下文“汗不厌迟”，通常理解为温热病早期即可考虑清里透热，不同于风寒必待表解），发汗不宜过早（意指不可单纯辛温发汗）。无论是使用和解法还是清解法，深浅层次绝不可拘泥。因为温热之气都属于热性，热能产生蒸腾作用，不必像寒邪那样需要郁结转化，而这种蒸腾本身就带有彼处的热势。如果在邪气未出表时误用温药，起初会导致热毒如火燎原，出现发斑、鼻衄、狂躁、气喘等症状，最后传变则会损伤真阴，出现干枯、昏沉、厥逆等各种危重证候。
三、辨别其传经规律的不同。温热病的传经方式，与风寒病不同。风寒病从表入里，所以必然从太阳经传到阳明经，再传到少阳经，最后传入胃腑；而温热病则是邪气从中道（脾胃/中焦）发起，或者在表，或者在里，完全视患者哪条经络的强弱来决定传变。所以伏邪发作时，有先表后里的，有先里后表的，有只在里不在表的，有在表后又复现于表的，有在里后又复现于里的，有表里偏胜的，有表里分传的，有表里分传后又再次分传的，有表里三焦同时发病的，这称为“九传”。医生必须先明白九传的道理，然后才能治疗伏邪。试述其要点：风寒病从表入里，必须等待逐渐闭郁后才传变，所以在表证阶段不必兼见里证，入里后也不必再见表证；温热病本就是从里出表，所以当见到表证时，没有不兼见一二个里证的，也没有不兼见一二个半表半里证的。而且温热病属于蒸气性质，表与里、里与表之间转换本来就不固定。有里有证用下法治疗后邪气未尽，仍可透出体表的；有在胡言乱语、昏沉之后，病愈数日，又出现头痛发热，再次通过汗法解除的，这就是所谓的“表而再表”，这是风寒病绝对没有的情况。更有甚者，具备全部下证，使用下药后，里气通畅而表气也通达，头痛发热得汗而解，胸闷心烦暂时通过疹斑排出而缓解，过了一会儿又出现舌黑、心闷、腹痛、胡言乱语，仍然需要大剂量攻下才能痊愈的，这就是所谓的“里而再里”，这也是风寒病绝对没有的情况。至于表里分传、三焦齐发的症状，风寒病十中无一二，温热病十中有六七，只需根据传经的专一或杂乱来辨别。初起只见到一条经络症状的属于风寒病，初起杂乱见到两三条经络症状的属于温热病；日久逐渐传变的属于风寒病，一天之内突然传变一到两条经络，或两三条经络的属于温热病。这样即使病情有变化，但风寒不会混同于温热，温热也不会混同于风寒，施治自然就不会有误了。
First, distinguish the difference in pathogenic qi. Wind primarily governs dispersion and leakage, while cold primarily governs coagulation and stagnation. Although these two types of qi differ, initially both are cold rather than hot. When they invade the human body, they cause stagnation without dissemination; therefore, when the pathogen is initially at the exterior level, it is appropriate to use warming and dispersing methods. Formulas such as Mahuang Tang (Ephedra Decoction), Guizhi Tang (Cinnamon Twig Decoction), Gegen Tang (Kudzu Root Decoction), and Suqiang Yin (Perilla and Notopterygium Drink) are all agents for dispersing cold, not for resolving heat. Warm-heat diseases arise from latent pathogens transforming into heat; they are hot rather than cold. When they damage the body, they immediately cause steaming and putrefaction, so cooling and resolving methods should be used from the onset. Formulas such as Zhichi Tang (Gardenia and Fermented Soybean Decoction), Gegen Qinlian Tang (Kudzu Root, Scutellaria, and Coptis Decoction), Maxing Shigan Gao (Ephedra, Apricot Kernel, Gypsum, and Licorice Paste), Huangqin Tang (Scutellaria Decoction), Weirui Tang (Polygonatum and Cistanche Decoction), and Liushentongjie San (Six Spirits Unblocking and Releasing Powder) are all agents for resolving heat, not for dispersing cold. Using heat-resolving agents to treat wind-cold may, in mild cases, lead to cold damaging the middle jiao causing vomiting and diarrhea; in severe cases, it may lead to sinking of yang and reversal cold (Jue Ni). Using cold-dispersing agents to treat warm-heat may, in mild cases, lead to epistaxis, thirst, delirium, and madness; in severe cases, it may lead to exhaustion of yin fluids and collapse of yin. This is why the nature of the pathogenic qi must be distinguished.
Second, distinguish the difference in the mode of invasion. Wind-cold enters from the exterior to the interior, progressing layer by layer from the skin and hair pores to the muscle interstices, then to the sinews and bones, and finally to the chest, diaphragm, stomach, and intestines. It cannot skip layers to enter directly; thus, sweating should not be delayed excessively, and purgation should not be initiated too early. Whether using dispersing or harmonizing methods, the depth of treatment must not be confused. Because the qi of wind-cold is cold, one must wait for the cold to transform into heat and for the pathogen to retreat inward before employing purgative and cooling methods; otherwise, the interior qi will be weakened, potentially drawing the exterior pathogen inward and resulting in conditions such as Jie Xiong (chest binding), Pi Li (fullness and diarrhea). Damp-warmth emerges from the Mo Yuan (membrane source), and warm-heat emerges from the blood collaterals. They first occupy the interior of the membrane and collaterals, requiring internal breakdown before manifesting the "Nine Transmissions." Although emerging from the interior to the exterior, even when at the exterior level, the interior may not be entirely free of lingering pathogen, and the semi-exterior/semi-interior levels traversed may also be injured by the pathogen. Therefore, purgation should not be delayed excessively, and sweating should not be initiated too early. Whether using harmonizing or resolving methods, the depth of treatment must not be rigidly adhered to. Because the qi of warm-heat is hot, heat generates steaming without needing the stagnation-transformation process required by cold; this steaming inherently carries heat from other areas. If warming agents are mistakenly used before the pathogen has exited the exterior, it will initially cause the heat toxin to spread like a prairie fire, leading to macules, epistaxis, mania, and panting; in the final transmission, it damages true yin, leading to critical conditions such as withering, coma, and reversal cold.
Third, distinguish the difference in meridian transmission. The transmission of warm-heat differs from that of wind-cold. Wind-cold moves from the exterior to the interior, necessarily transmitting from the Taiyang (Greater Yang) channel to the Yangming (Yang Brightness) channel, then to the Shaoyang (Lesser Yang) channel, and finally entering the Stomach. In contrast, warm-heat pathogens originate from the Middle Dao (Middle Jiao/Spleen-Stomach region) and may appear in the exterior or interior, depending on the strength or weakness of the patient's meridians for transmission. Thus, when latent pathogens erupt, there are cases of exterior preceding interior, interior preceding exterior, interior only without exterior, exterior recurring after initial resolution, interior recurring after initial resolution, predominance of either exterior or interior, simultaneous transmission of exterior and interior, repeated simultaneous transmission, and simultaneous eruption of exterior, interior, and the Three Jiao. These are termed the "Nine Transmissions." Physicians must understand the rationale behind the Nine Transmissions to treat latent pathogens. To summarize: Wind-cold transmits from exterior to interior, requiring gradual closure and stagnation before transmission; thus, during the exterior stage, interior symptoms need not be present, and after entering the interior, exterior symptoms need not reappear. Warm-heat originates from the interior emerging to the exterior; therefore, when exterior symptoms appear, they are invariably accompanied by one or two interior symptoms, and also by one or two semi-exterior/semi-interior symptoms. Moreover, warm-heat belongs to vapor-like qi, where the transition between exterior and interior is not fixed. There are cases where interior symptoms are treated with purgatives but the pathogen remains incomplete and can still emerge to the exterior; there are cases where, after delirium and coma, the illness subsides for several days, only to reappear with headache and fever, resolving again through sweating. This is called "exterior recurring," which never happens with wind-cold. Furthermore, there are cases where all purgative indications are present; after using purgatives, the interior qi becomes unblocked and the exterior qi also reaches the surface, with headache and fever resolving through sweat, and chest fullness and irritability temporarily resolving through rashes and macules. However, after a short time, black tongue, chest oppression, abdominal pain, and delirium reappear, requiring massive purgation to heal. This is called "interior recurring," which also never happens with wind-cold. Regarding symptoms of simultaneous exterior-interior transmission and Three Jiao eruption, these occur in less than 10-20% of wind-cold cases but in 60-70% of warm-heat cases. Differentiation relies solely on whether the transmission is specific or mixed. Initial presentation of symptoms in a single meridian indicates wind-cold; initial presentation of mixed symptoms in two or three meridians indicates warm-heat. Gradual transmission over many days indicates wind-cold; sudden transmission involving one to three meridians within a day indicates warm-heat. Thus, although diseases may vary in manifestation, wind-cold will not be confused with warm-heat, nor warm-heat with wind-cold, ensuring accurate treatment.