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、葛根芩连汤、麻杏石甘汤、黄芩汤、葳蕤汤、六
神通解散等方，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、痢诸症。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；未传则伤真阴，为枯槁、沉昏、厥逆、诸危候矣！（邴味清评∶此论深有见识。）
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，此为九传。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、辨别病邪性质的差异
风邪主疏泄，寒邪主凝滞涩结。这两种邪气虽然不同，但初起时都表现为冷而不热。当它们侵袭人体时，会导致气机郁闭而不能宣发。在疾病初期，邪气尚在体表，适宜采用温散的方法治疗。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势，发病初期就应当采用清凉解表的方法治疗。栀豉汤、葛根芩连汤、麻杏石甘汤、黄芩汤、葳蕤汤、六神通解散等方剂，都是清热解表的药剂，而不是发散寒邪的药剂。如果用清热解表的药剂去治疗风寒病，轻则导致寒邪伤中引起呕吐腹泻，重则导致阳气下陷出现四肢厥逆；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失。这就是病邪性质不可不加以辨别的道理。
二、辨别感邪途径的差异
风寒之邪从体表进入体内，依次经过皮毛、肌腠、筋骨、胸膈和胃肠，一层层逐渐深入，不能跨越这一层直接侵入下一层。因此，发汗法不宜过晚，攻下法不宜过早，无论是使用发散法还是调和法，深浅程度都必须严格把握，不可紊乱。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，才可以采用攻下或清凉解表的方法，否则会使里气虚弱，反而引发表邪内陷，形成结胸、痞证、痢疾等各种病症。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，必须内部溃败后才能转变为九种传变方式，由里出表。虽然邪气出于体表，但体内未必完全没有残留的邪气，经过的半表半里部位，也未必没有受到邪气伤害。因此，攻下法不宜过晚，发汗法不宜过早，无论是使用调和法还是解表法，深浅程度绝不可拘泥固定。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，这种蒸腾本身就带有热势。如果在邪气尚未出表时就误用温药，起初会引动热毒燎原，出现发斑、鼻衄、狂躁、气喘等症状；如果邪气尚未传变就误用温药，则会损伤真阴，出现干枯憔悴、深度昏迷、四肢厥逆等各种危重征候！（邴味清评：这段论述很有见识。）
三、辨别传经规律的差异
温热病的传经规律与风寒病不同。风寒病从体表进入体内，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）发起，或者表现在表，或者表现在里，完全视人体各经络强弱的情况而定。因此，伏邪发作时，有先表现表证后表现里证的，有先表现里证后表现表证的，有只表现里证不表现表证的，有表证反复出现的，有里证反复出现的，有表里偏胜的，有表里同时传变的，有表里分传后又再次分传的，有表里和三焦同时爆发的，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发生传变，所以在表证阶段不一定兼见里证，入里后也不一定再见表证。温热病本是从里出表，所以当见到表证时，无不兼见一二个里证，也无不兼见一二个半表半里证。而且温热属于蒸气性质，表与里、里与表的变化原本就不固定，有的虽有里证用了下法但邪气未尽，仍可转出体表；有的在胡言乱语、昏沉之后，病愈数日，又出现头痛发热，再次通过出汗而解除。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，头痛发热通过出汗解除，胸闷心烦暂时通过发疹发斑解除，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。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。初起专门表现一经症状的属于风寒，初起杂乱表现两三条经症状的属于温热，日久逐渐传变的属于风寒，一天之内突然传变一到两条或两三条经的属于温热。这样即使病情有变化，也能使风寒不与温热混淆，温热不与风寒混淆，施治自然就不会有误了。
1. Differentiating the Nature of Pathogenic Factors
Wind pathogen governs dispersion and leakage, while cold pathogen governs coagulation and stagnation. Although these two pathogens differ, both initially present as cold rather than hot. When invading the human body, they cause qi mechanism to be constrained and unable to diffuse. In the early stage, when the pathogen is still at the exterior, it is appropriate to use warm 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 agents for dispersing cold, not for clearing heat. Warm-heat diseases arise from latent pathogens transforming into heat; their nature is hot rather than cold. When injuring the human body, they immediately generate steaming and corrupting effects, 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, Coptis, and Scutellaria Decoction), Maxing Shigan Tang (Ephedra, Apricot Kernel, Gypsum, and Licorice Decoction), Huangqin Tang (Scutellaria Decoction), Zhirui Tang (Jujube Seed Decoction), and Liushentongjie San (Six Spirits Unblocking Powder) are agents for clearing heat and resolving the exterior, not for dispersing cold. Using heat-clearing agents to treat wind-cold may, in mild cases, cause cold to injure the middle jiao leading to vomiting and diarrhea, or in severe cases, lead to sinking of yang and cold extremities. Using cold-dispersing agents to treat warm-heat may, in mild cases, cause nasal bleeding, thirst, delirium, and madness, or in severe cases, lead to exhaustion of yin fluids. This is why the nature of the pathogen must be differentiated.
2. Differentiating the Route of Invasion
Wind-cold pathogens enter from the exterior to the interior, progressing layer by layer from skin and hair pores to muscle interstices, sinews and bones, chest and diaphragm, and finally stomach and intestines. They cannot skip layers to invade directly. Therefore, sweating therapy should not be delayed, and purging therapy should not be initiated too early. Whether using dispersing or harmonizing methods, the depth of treatment must be strictly controlled without disorder. Because wind-cold qi belongs to the cold category, one must wait for the cold to transform into heat and for the pathogen to retreat inward before applying purging or cooling-resolving methods. Otherwise, the interior qi will be weakened, potentially drawing exterior pathogens inward and resulting in conditions such as Jie Xiong (chest binding), Pi Zheng (fullness syndrome), and dysentery. Damp-warmth diseases erupt from the Mo Yuan (membrane source), while warm-heat diseases erupt from blood collaterals. Initially occupying the membrane and collaterals, internal collapse must occur before transforming into the nine modes of transmission, moving from interior to exterior. Even when pathogens emerge to the exterior, the interior may not be entirely free of lingering pathogens, and the semi-exterior/semi-interior regions traversed may also be injured by pathogens. Therefore, purging should not be delayed, and sweating should not be initiated too early. Whether using harmonizing or resolving methods, the depth of treatment must not be rigidly fixed. Because warm-heat qi belongs to the heat category, heat generates steaming effects without needing the constraint-transformation process of cold. This steaming inherently carries heat. If warming agents are mistakenly used before pathogens have emerged to the exterior, it may initially trigger a prairie fire of heat toxins, leading to macules, epistaxis, mania, and wheezing. If warming agents are used before transmission occurs, it damages true yin, leading withered states, deep coma, cold extremities, and other critical signs. (Comment by Bing Weiqing: This discussion demonstrates profound insight.)
3. Differentiating the Patterns of Transmission
The transmission patterns of warm-heat diseases differ from those of wind-cold. Wind-cold moves from exterior to interior, necessarily transmitting from Taiyang (Greater Yang) to Yangming (Yang Brightness), then to Shaoyang (Lesser Yang), and finally entering the Stomach. In contrast, warm-heat pathogens originate from the Middle Jiao (Middle Burner) and may manifest in the exterior or interior, depending on the strength or weakness of the respective meridians in the individual. Thus, upon eruption of latent pathogens, there are cases where exterior symptoms precede interior ones, where interior symptoms precede exterior ones, where only interior symptoms appear without exterior ones, where exterior symptoms recur, where interior symptoms recur, where exterior or interior aspects predominate, where exterior and interior transmit simultaneously, where simultaneous transmission recurs, and where exterior, interior, and all three jiaos erupt together. These are known as the "Nine Transmissions." Physicians must first understand the rationale behind the Nine Transmissions to effectively treat latent pathogens. Let us discuss the essentials. Wind-cold moves from exterior to interior and requires gradual constraint and accumulation before transmission occurs. Therefore, during the exterior phase, interior symptoms are not necessarily present, and after entering the interior, exterior symptoms do not necessarily reappear. Warm-heat originates from the interior emerging to the exterior; thus, when exterior symptoms appear, they are invariably accompanied by one or two interior symptoms, and also invariably accompanied by one or two semi-exterior/semi-interior symptoms. Furthermore, warm-heat consists of vapor-like qi, making the transition between exterior and interior fluid and irregular. Some cases with interior symptoms, even after purgation, fail to clear all pathogens and can still emerge to the exterior. Some cases, after delirium and stupor, recover for several days, then present again with headache and fever, resolving through sweating. This is called "exterior recurring," which is impossible in wind-cold. Moreover, in cases presenting with complete indications for purgation, after administering purgatives, if interior qi becomes unblocked and exterior qi also reaches the surface, headache and fever resolve through sweating, and chest tightness and irritability temporarily resolve through rashes and macules, but later tongue blackening, chest oppression, abdominal pain, and delirium reappear, requiring massive purgation for cure, this is called "interior recurring," which is also impossible in wind-cold. Regarding simultaneous exterior-interior transmission and pan-three-jiao eruption, these account for one or two out of ten cases in wind-cold, but six or seven out of ten in warm-heat. Differentiation relies solely on whether transmission is specific/uniform or mixed/disordered. Initial presentation of symptoms confined to one meridian indicates wind-cold; initial presentation of mixed symptoms across two or three meridians indicates warm-heat. Gradual transmission over many days indicates wind-cold; sudden transmission involving one to three meridians within a single day indicates warm-heat. Thus, despite variations in disease manifestation, wind-cold will not be confused with warm-heat, nor warm-heat with wind-cold, ensuring accurate treatment.