或曰∶恶寒何以是表证？答曰∶人身外为阳、为表，寒邪属阴，由表虚为寒所乘，名曰
阴盛阳虚也。阳虚不能温其肤卫，致表空虚，虽在密室，亦引衣盖覆，谓之恶寒。经云∶阴
盛阳虚，汗之则愈。故恶寒属表证。又问曰∶诸书言里证亦恶寒，何也？答曰∶里证恶寒直
中也，非传经也。传经入里则为热邪，必然恶热，岂有恶寒之理。然太阳恶寒，与直中恶寒
何以别之？病患头痛发热而恶寒者，表证也；无头痛发热而恶寒者，直中里证也。经云∶
发热恶寒发于阳，无热恶寒发于阴也。又问曰∶阳明腑病，口燥渴而背微恶寒者，岂非传经
里证乎？答曰∶恶寒者，表未尽也，因其燥渴之甚，故用白虎加人参汤，此活法也。仲景云
∶发热无汗，表未解者，不可与白虎汤，渴欲饮水，无表证者，白虎加人参汤主之。此证微
恶寒，则表邪将解，口燥渴，则里热已炽，故用此方。设口不燥渴，亦安得而用之乎？又问
曰∶误下而成结胸，胀痛甚急，倘恶寒者，何以治之？答曰∶结胸为医误下而成，今恶寒者
是表邪未尽结于胸中，必先解表，方服陷胸汤、丸，若误攻之，表邪又结于胸，则更危
矣。故结胸证，有一毫恶寒，必先散之而后攻之。可见恶寒属太阳表证也。
问曰∶喘何以是太阳证？答曰∶肺主皮毛，司气之升降，寒邪侵于皮毛，肺气不得升降
故喘。试以麻黄汤论之，内有杏仁，为定喘设也。又云∶喘家作桂枝汤，加浓朴、杏子佳
明言喘属表邪也。又问曰∶喘既为肺、为表，《指掌赋》云喘满而不恶寒者，当下而痊，
何也？答曰∶传经里证内热闭结，大便不通，热气上冲，致肺金清肃之令不得下行，因而喘
急，此因胃热攻肺，故可下之，俾其热气流通而喘定矣。然或有恶寒等证，则不可遽攻，恐
成逆候。又问曰∶阴证喘促者，何以治之？答曰∶阴证喘者，乃少阴中寒，真阳衰微，肾不
纳气，以致四肢厥冷，脉沉细，气促而喘急，宜理中、四逆以温之，八味以佐之。若汗出发
润，喘不休者，为难治也。
有人问：为什么恶寒属于表证？回答说：人体外部属阳、属表，寒邪属阴，因体表虚弱而被寒邪侵袭，这叫做阴盛阳虚。阳气虚弱不能温煦肌肤卫外，导致体表空虚，即使在密闭的房间里，也会拉衣盖被，这就是所谓的恶寒。医经说：阴盛阳虚，用发汗法治疗就会痊愈。所以恶寒属于表证。又问：许多书籍说里证也有恶寒，这是为什么呢？回答说：里证的恶寒是寒邪直中脏腑，不是由表传里的。病邪由表传里就变成热邪，必然怕热，哪里有怕冷的道理。然而太阳病的恶寒与寒邪直中的恶寒如何区别呢？病人头痛、发热且恶寒的，是表证；没有头痛、发热而恶寒的，是寒邪直中的里证。医经说：发热恶寒发于阳经，无热恶寒发于阴经。又问：阳明腑病，口燥渴且背部微恶寒的，难道不是传经入里的证候吗？回答说：恶寒说明表邪尚未完全解除，因为燥渴非常严重，所以使用白虎加人参汤，这是灵活变通的方法。张仲景说：发热无汗，表证未解的，不可给予白虎汤；口渴想喝水，没有表证的，以白虎加人参汤为主治。此证微恶寒，说明表邪将要解除，口燥渴，说明里热已经炽盛，所以使用这个方剂。如果口不燥渴，怎么能使用它呢？又问：误用下法导致结胸，胀痛非常急迫，如果有恶寒症状，该如何治疗？回答说：结胸是由于医生误用下法造成的，现在出现恶寒，是表邪未尽并结聚在胸中，必须先解表，然后才能服用陷胸汤或陷胸丸，如果错误地攻下，表邪又会结聚在胸中，那就更加危险了。所以结胸证，只要有一点点恶寒，必须先发散表邪然后再攻逐里实。由此可见，恶寒属于太阳表证。
问：为什么喘属于太阳证？回答说：肺主皮毛，主管气的升降，寒邪侵犯皮毛，肺气不能正常升降，所以发生喘。试以麻黄汤为例分析，方中有杏仁，是为了定喘而设的。又说：素有喘疾的人发作时，用桂枝汤，加上厚朴、杏子效果更佳，明确说明喘属于表邪所致。又问：既然喘与肺和表有关，《指掌赋》说喘满且不恶寒的，应当用下法治愈，这是为什么呢？回答说：传经入里的证候，内热闭结，大便不通，热气上冲，导致肺金清肃的功能不能下行，因而喘急，这是因胃热攻冲肺部，所以可以用下法，使热气流通而喘止。但是如果有恶寒等症状，则不可以立即攻下，恐怕造成逆证。又问：阴证喘促的，该如何治疗？回答说：阴证的喘，是少阴经受寒，真阳衰微，肾不纳气，以致四肢厥冷，脉象沉细，气短促而喘急，适宜用理中汤、四逆汤来温补，用八味丸来辅助。如果出现汗出如油、喘促不止的情况，就属于难治之症。
A question is raised: Why is aversion to cold (Ehan) considered a exterior syndrome? The answer is: The exterior of the human body belongs to Yang and the exterior level. Cold pathogen belongs to Yin. When the exterior is deficient, it is invaded by cold, which is termed as excessive Yin and deficient Yang. Due to deficient Yang failing to warm the skin and defensive Wei Qi, the exterior becomes empty; thus, even in a sealed room, one will pull clothes to cover up. This is called aversion to cold. The Classics state: "In cases of excessive Yin and deficient Yang, sweating therapy leads to recovery." Therefore, aversion to cold belongs to exterior syndromes.
Another question arises: Many texts mention that interior syndromes also present with aversion to cold. Why is this so? The answer is: Aversion to cold in interior syndromes results from direct invasion (Zhizhong) of cold pathogens into the interior, not from transmission via meridians. Once pathogens transmit into the interior, they transform into heat pathogens, inevitably causing aversion to heat (Ai Re). How can there be aversion to cold then? However, how do we distinguish between the aversion to cold in Taiyang disease and that caused by direct invasion? If a patient has headache, fever, and aversion to cold, it is an exterior syndrome; if there is no headache or fever but only aversion to cold, it is an interior syndrome due to direct invasion. The Classics state: "Fever with aversion to cold originates from Yang [exterior]; absence of fever with aversion to cold originates from Yin [interior]."
Another question: In Yangming Fu-organ disease, if there is dry mouth and thirst accompanied by slight aversion to cold on the back, is this not an interior syndrome resulting from transmission? The answer is: The presence of aversion to cold indicates that the exterior pathogen has not yet fully resolved. Because the dryness and thirst are severe, Baihu Jia Renshen Tang (White Tiger Decoction plus Ginseng) is used. This is a flexible application. Zhang Zhongjing stated: "If there is fever and no sweat, indicating the exterior is unresolved, Baihu Tang should not be given. If there is thirst for water and no exterior syndrome, Baihu Jia Renshen Tang is the primary treatment." In this case, slight aversion to cold suggests the exterior pathogen is about to resolve, while dry mouth and thirst indicate intense interior heat. Hence, this formula is used. If there were no dry mouth and thirst, how could it be used?
Another question: If mistaken purgation leads to Jie Xiong (Chest Binding), with severe and urgent distending pain, what if aversion to cold is present? How should it be treated? The answer is: Jie Xiong is caused by physician's error in purgation. The current aversion to cold indicates that exterior pathogens remain unresolved and are binding in the chest. One must first release the exterior before administering Xiaoxiong Tang or Wan (Harmonizing Chest Decoction/Pills). If mistakenly attacked with purgatives, the exterior pathogens will bind further in the chest, leading to a more critical condition. Thus, in Jie Xiong syndrome, even a trace of aversion to cold requires dispersing the exterior first, followed by attacking the interior. This demonstrates that aversion to cold belongs to Taiyang exterior syndromes.
Question: Why is panting/chuan (Chuan) considered a Taiyang syndrome? Answer: The Lung governs the skin and hair and regulates the ascending and descending of Qi. When cold pathogens invade the skin and hair, Lung Qi cannot ascend and descend properly, resulting in panting. Consider Mahuang Tang (Ephedra Decoction): it contains Xingren (Apricot Seed), which is specifically set to stop panting. It is also stated: "For patients with chronic panting, Guizhi Tang (Cinnamon Twig Decoction) added with Houpo (Magnolia Bark) and Xingzi (Apricot Seed) is excellent." This explicitly states that panting belongs to exterior pathogens.
Another question: Since panting relates to the Lung and the exterior, why does the *Zhangzhang Fu* (Song of Finger Points) state that panting and fullness without aversion to cold should be treated with purgation for recovery? The answer is: In transmitted interior syndromes, internal heat binds tightly, feces are not unblocked, and hot qi rushes upward. This prevents the Lung Metal from performing its clearing and descending function, leading to urgent panting. This is caused by Stomach heat attacking the Lung, so purgation can be used to allow hot qi to circulate freely, thereby stopping the panting. However, if symptoms like aversion to cold are present, immediate purgation is contraindicated to avoid adverse outcomes.
Another question: How should panting in Yin syndromes be treated? The answer is: Panting in Yin syndromes results from Shaoyin channel cold invasion, where true Yang is severely deficient, and the Kidney fails to grasp Qi. This leads to cold limbs, deep and fine pulse, shortness of breath, and urgent panting. Li Zhong Tang (Regulate the Middle Decoction) and Sini Tang (Frigid Extremities Decoction) should be used to warm the body, supplemented by Bawei Wan (Eight-Ingredient Pill). If sweating occurs with moist hair and continuous panting, it is difficult to treat.