寒最要者，表里二字。而表里中，又有兼风兼湿之别。风寒病太阳，湿寒病太阴。伏
气治少阴，感冒治少阳。第拘标本言，少阴太阳司此气耳。余惟太阴亦多，至少阳阳明
厥阴三经，即系寒病，每从热化，和解可也。当与前六气参看。
温热之论，叶香岩寻其源。风湿之分，陈平伯溯其流。厥后吴氏鞠通，祖述叶案，而
着《条辨》。王氏孟英，宪章平伯，而纂《经纬》。治温津梁诸书备已。然一则界划三焦，
一则伏气未达，智者一失，殊为二先生惜。今将风湿分两段，持前人言，以明其义，庶长
夜一灯，不致盲人摸索。
吴鞠通曰∶风有温有寒。风寒之风，此风从北方来，乃触发之寒风也。最善收引，阴盛
必伤阳，故首郁遏太阳经中之阳气，而为头痛，身热等证。太阳阳腑也，伤寒阴邪也，阴盛
伤人之阳也，故曰风寒。风温之风，此风从东方来，乃解冻之温风也。最善发泄，阳盛必伤
阴，故首郁遏太阴经中之阴气，而为咳嗽，自汗，口渴，头痛，身热等证。太阴阴脏也，温热
阳邪也，阳盛伤人之阴也，故曰风温。
叶子雨曰∶湿温之因有三，阳脉濡而弱，阴脉小而急，此先受暑，后中湿，乃暑邪蒸湿
者是也。证见两胫冷，腹满，又胸头目痛，妄言，治在足太阴，不可发汗。由先伤于脾，因而
中，湿热相搏者是也。脉濡弱，舌苔白或绛底，呕逆口干，不能汤饮，胸满闷，身潮热，汗
出稍凉，少顷又热，此春分后，秋分前，少阴君火，少阳相火，太阴湿土，三气合行，加以天气
热下降，地气湿上腾，由口鼻吸受，着于脾胃者是也。误治变证，非一端所能尽。夫湿自外
来，上焦气分受之，潮热，自汗，表之不解，清之不应，宜宣通气分。若冒雨雾，湿留太阴，肌
表发热，自汗，不渴，不饮，舌苔灰白，粘腻，身虽热，不欲去衣被者，宜解肌和表。论证不清，
鲜有不偾事者。
寒邪致病，最关键的是“表”与“里”这两个概念。而在表里之中，又有兼夹风邪或湿邪的区别。风寒之邪多侵犯太阳经，湿寒之邪多侵犯太阴经。伏气温病（邪气潜伏体内后发作的病）治在少阴经，外感温病（感受外界温热邪气而发病）治在少阳经。但如果拘泥于标本理论来说，主要是少阴和太阳两经主管这类病气。其余如太阴经也多有此病，至于少阳、阳明、厥阴这三条经络，即使是寒邪致病，也往往从热化，可以采用和解法治疗。应当与前文提到的六气（风、寒、暑、湿、燥、火）理论参看。
关于温热病的论述，叶天士（字香岩）探寻其源头。风湿病的区分，陈平伯追溯其流变。此后吴鞠通（名瑭），效法叶天士的医案，撰写了《温病条辨》。王孟英（名士雄），遵循陈平伯的理论，编纂了《温热经纬》。治疗温病的书籍已经非常完备了。但是，吴鞠通则以三焦为界限划分病位，而未能透彻阐述伏气温病的机理，这是智者的失误，实在令人惋惜这两位先贤。现在我将风湿分为两部分，引用前人的言论来阐明其义理，希望在漫长的黑夜中有一盏灯，不至于让盲人摸索前行。
吴鞠通说：风邪有温风和寒风之分。风寒中的风，是从北方来的，是触发疾病的寒风。它最善于收敛牵引，阴气盛必然损伤阳气，所以首先郁遏太阳经中的阳气，导致头痛、身热等症状。太阳属阳腑，伤寒属阴邪，阴气盛损伤人的阳气，所以称为风寒。风温中的风，是从东方来的，是解冻的温风。它最善于发散发泄，阳气盛必然损伤阴液，所以首先郁遏太阴经中的阴气，导致咳嗽、自汗、口渴、头痛、身热等症状。太阴属阴脏，温热属阳邪，阳气盛损伤人的阴液，所以称为风温。
叶子雨说：湿温病的成因有三种情况。一是脉象表现为阳脉濡弱，阴脉细小而急，这是先感受暑邪，后又中湿，属于暑邪蒸腾湿气的类型。症状见两小腿发冷，腹部胀满，以及胸头目痛，胡言乱语，治疗应在足太阴脾经进行，不可使用发汗法。二是由于先伤于脾，进而中湿，湿热相互搏结的类型。脉象濡弱，舌苔白或底绛，呕吐逆气，口干，无法喝水，胸部满闷，身体潮热，出汗后稍凉，片刻后又发热，这是在春分后、秋分前，少阴君火、少阳相火、太阴湿土三气共同作用，加上天气热下降，地气湿上升，通过口鼻吸入，附着于脾胃的类型。误治导致的变证，不是一方面能说完的。三是湿气从外来，上焦气分受邪，出现潮热、自汗，解表不解，清热无效，适宜宣通气分。如果是冒雨雾，湿气停留在太阴，肌表发热，自汗，不渴，不想喝水，舌苔灰白粘腻，身体虽热但不想脱衣被的，适宜解肌和表。如果论证不清，很少有不失败出错的。
The most critical aspect of Cold pathogen diseases lies in the concepts of Exterior (Biao) and Interior (Li). Within these, there are distinctions between those complicated by Wind (Feng) or Dampness (Shi). Wind-Cold diseases affect the Taiyang Channel (Taiyang Meridian), while Damp-Cold diseases affect the Taiyin Channel (Taiyin Meridian). Latent Qi diseases (diseases caused by pathogens lying dormant in the body) are treated via the Shaoyin Channel (Shaoyin Meridian), whereas common colds (exogenous warm diseases) are treated via the Shaoyang Channel (Shaoyang Meridian). However, if adhering strictly to the theory of Root and Branch (Ben-Biao), it is primarily the Shaoyin and Taiyang channels that govern this type of pathogenic Qi. The Taiyin channel also frequently involves such diseases. As for the Shaoyang, Yangming, and Jueyin channels, even when they involve Cold pathogen diseases, they often transform into Heat; therefore, Harmonizing methods (He Jie) may be applied. This should be cross-referenced with the theory of the Six Qi (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) mentioned earlier.
Regarding theories on Warm-Thermal diseases, Ye Tianshi (courtesy name Xiangyan) explored their origins. Chen Pingbo traced the evolution of the distinction between Wind-Damp diseases. Later, Wu Jutong (Wu Tang) followed Ye’s medical cases and authored *Wen Bing Tiao Bian* (Systematic Differentiation of Warm Diseases). Wang Mengying (Wang Shiyong) modeled his work after Chen Pingbo and compiled *Wen Re Jing Wei* (Classic and Standard Texts on Warm-Heat Diseases). Books on treating Warm diseases are already abundant. However, Wu Jutong delineated boundaries according to the San Jiao (Triple Burner), yet failed to fully elucidate the mechanism of latent Qi, which is a lapse by a wise man, truly regrettable for both gentlemen. Now, I divide Wind-Damp into two parts, citing predecessors' words to clarify their meanings, hoping to provide a lamp in the long night so as not to leave blind men groping in the dark.
Wu Jutong stated: Wind has Warm and Cold varieties. The wind in Wind-Cold comes from the North; it is a chilling wind that triggers disease. It is most adept at contracting and pulling inward. When Yin is excessive, it inevitably damages Yang. Thus, it first stagnates the Yang Qi within the Taiyang Channel, leading to symptoms such as headache and fever. Taiyang belongs to the Yang Fu organs (Yang Bowels), while Cold Injury belongs to Yin pathogens. Excessive Yin damages human Yang, hence it is called Wind-Cold. The wind in Wind-Warmth comes from the East; it is a warming wind that thaws ice. It is most adept at dispersing and venting outward. When Yang is excessive, it inevitably damages Yin fluids. Thus, it first stagnates the Yin Qi within the Taiyin Channel, leading to symptoms such as cough, spontaneous sweating, thirst, headache, and fever. Taiyin belongs to the Yin Zang organs (Yin Viscera), while Warm-Thermal pathogens belong to Yang pathogens. Excessive Yang damages human Yin, hence it is called Wind-Warmth.
Zi Yuyu stated: There are three causes for Damp-Warmth diseases. First, the pulse presents as superficial (Yang) soft and weak, and deep (Yin) small and rapid. This indicates prior exposure to Summer-heat followed by Dampness, where Summer-heat steams the Dampness. Symptoms include coldness in both calves, abdominal fullness, pain in the chest, head, and eyes, and delirious speech. Treatment should focus on the Foot-Taiyin Spleen Channel, and sweating methods must not be used. Second, injury to the Spleen occurs first, leading to internal Dampness, where Dampness and Heat contend. The pulse is soft and weak, the tongue coating is white or crimson underneath, there is vomiting and regurgitation, dry mouth, inability to drink water, chest fullness and oppression, tidal fever, sweating brings slight relief but heat returns shortly after. This occurs between the Spring Equinox and Autumn Equinox, when the Ministerial Fire of Shaoyin, the Host Fire of Shaoyang, and the Damp Earth of Taiyin act together. Combined with hot air descending and damp air ascending, inhaled through the nose and mouth, it attaches to the Stomach and Spleen. Misdiagnosis leads to complications that cannot be exhaustively listed. Third, Dampness comes from outside, affecting the Qi level of the Upper Jiao. Symptoms include tidal fever and spontaneous sweating. If exterior resolution fails and clearing heat is ineffective, ventilating the Qi level is appropriate. If one is exposed to rain and fog, leaving Dampness in the Taiyin, with fever in the muscle and surface, spontaneous sweating, no thirst, no desire to drink, grey-white sticky tongue coating, and despite body heat, a reluctance to remove clothes and blankets, resolving the muscle layer and harmonizing the exterior is appropriate. If the syndrome differentiation is unclear, failure is almost inevitable.