阳症者，即《内经》伤寒之热病也。使阳症而见热象，人所易知。阳症而反见阴寒之象，则人
惑之矣。例如太阴病，下利日十余行，必自止，以脾家实，秽腐当去故也；少阴病四逆，其
人或咳或悸，四逆散主之；少阴病自利清水色纯青，而用大承气汤者；厥阴病手足厥冷，用
吐之者；厥阴先发热而发厥冷，用四逆散者。凡此皆是阳症似阴之症。又如原病式云∶阴厥
者，元病脉候皆为阴症，身凉不渴，神志清爽，脉迟而微，未尝见一些阳症者也；阳厥者，
元病脉候皆为阳症，忽尔厥冷，烦渴昏沉，脉虽细而沉数，此是阳症似阴也。
宜发表者，邪在肌表，郁而发热，故用发汗散邪之法。症在太阳者，羌独败毒散煎汤连饮；
里有热者，羌活冲和汤。此二方，即以麻黄、桂枝辛温汤中，化立辛凉散表，以治南方伤寒
发汗解肌之法。症见阳明，则从干葛汤中去麻黄桂枝，更名升麻干葛汤，平淡轻清之味。惟
少阳一症，仍照小柴胡汤；但以寒多者，倍加羌活、防风减黄芩治之。若三阳俱见症者，三
经合参用药。故曰恶寒身痛者，宜发表。支节烦疼者，宜发表。头痛项强者，宜发表。四肢
常冷者，宜发表。四肢拘紧不能转侧者，宜发表。面赤身热，两足常冷，或脉沉伏者，宜发
表。时刻呻吟，语言不足，无汗烦躁者，宜发表。身体乍轻乍重，转侧或难或易，宜发表。
身痛乍在四肢，乍在胸背，到底无定者，宜发表。洒洒恶风，皮肤大热，宜发表。以上三阳
经表邪之症，故用发表之法。
阳证，就是《内经》中所说的伤寒热病。如果阳证表现出热象，人们很容易知晓；但如果阳证反而表现出阴寒的征象，人们就会感到困惑了。例如太阴病，每天腹泻十几次，必定会自行停止，这是因为脾家实证，体内的污秽腐浊之物应当排出的缘故；少阴病出现四肢厥逆，其人或者咳嗽或者心悸，用四逆散主治；少阴病自利清水且颜色纯青，而使用大承气汤治疗的；厥阴病手足厥冷，采用吐法治疗的；厥阴病先发热而后发手足厥冷，用四逆散治疗的。凡此种种，都是阳证似阴的病证。又如《原病式》所说：阴厥者，其病因脉候都表现为阴证，身体凉爽不口渴，神志清爽，脉象迟而微弱，未曾见到丝毫阳证的表现；阳厥者，其病因脉候都表现为阳证，忽然手足厥冷，烦躁口渴昏沉，脉象虽然细但沉取数急，这是阳证似阴的表现。
宜于发表（通过发汗解除表邪）的情况，是邪气在肌表，郁结而发热，所以用发汗散邪的方法。病症在太阳经的，用羌活败毒散煎汤连续服用；里有热的，用羌活冲和汤。这两个方剂，即在麻黄、桂枝辛温的汤剂中，化生出辛凉解散表邪的功效，以治疗南方伤寒发汗解肌的方法。病症见于阳明经的，就从干葛汤中去掉麻黄、桂枝，改名为升麻干葛汤，药性平淡轻清。只有少阳一经的病证，仍按照小柴胡汤；但如果寒象多者，加倍加入羌活、防风，减少黄芩来治疗。如果三阳经同时出现症状的，综合三经参酌用药。所以说：恶寒身痛的，宜于发表。肢节烦疼的，宜于发表。头痛项强的，宜于发表。四肢常冷的，宜于发表。四肢拘紧不能转侧的，宜于发表。面赤身热，两足常冷，或者脉象沉伏的，宜于发表。时刻呻吟，语言低微无力，无汗烦躁的，宜于发表。身体时而轻快时而沉重，转侧有时困难有时容易的，宜于发表。身痛有时在四肢，有时在胸背，始终没有定处的，宜于发表。怕风如洒冷水般，皮肤大热的，宜于发表。以上三阳经表邪的症状，所以用发表的方法。
Yang syndromes refer to the febrile diseases of cold damage as described in the *Neijing* (Classic of Internal Medicine). If a Yang syndrome presents with heat manifestations, it is easily recognized by people. However, if a Yang syndrome instead presents with Yin-cold manifestations, people will be confused. For example, in Taiyin disease, where there is diarrhea more than ten times a day, it must stop spontaneously because of the excess condition in the Spleen system, implying that foul and corrupt matter should be expelled; for Shaoyin disease presenting with four-inverse (cold extremities), if the patient also has cough or palpitations, Si Ni San (Four Inversion Powder) is the primary prescription; for Shaoyin disease with spontaneous purgation of clear water that is purely green in color, Da Cheng Qi Tang (Major Order the Qi Decoction) is used; for Jueyin disease with cold extremities, emesis therapy is employed; for Jueyin disease where fever occurs first followed by cold extremities, Si Ni San (Four Inversion Powder) is used. All these are examples of Yang syndromes resembling Yin syndromes. Furthermore, as stated in the *Yuan Bing Shi* (Treatise on the Original Causes of Diseases): In Yin-jue (Yin cold extremities), the etiology, pulse, and signs all manifest as Yin syndromes; the body is cool without thirst, the spirit and consciousness are clear, the pulse is slow and faint, and not a single Yang sign is observed. In Yang-jue (Yang cold extremities), the etiology, pulse, and signs all manifest as Yang syndromes; suddenly the extremities become cold, accompanied by irritability, thirst, and lethargy; although the pulse is fine, it is deep and rapid upon deep pressure. This is a case of a Yang syndrome resembling a Yin syndrome.
Indications for releasing the exterior involve pathogens located in the muscle layer and skin, causing stagnation and fever; therefore, methods of inducing sweating to scatter pathogens are used. When the syndrome is in the Taiyang channel, Qiang Huo Bai Du San (Notopterygium and Detoxification Powder) is decocted and taken continuously. If there is heat in the interior, Qiang Huo Chong He Tang (Notopterygium and Harmony Decoction) is used. These two formulas transform the acrid-warm nature of Mahuang Tang (Ephedra Decoction) containing Ephedrae Herba (Mahuang, 麻黄) and Cinnamomi Ramulus (Guizhi, 桂枝) into an acrid-cool method for dispersing the exterior, serving as the method for inducing sweat and resolving the muscle layer in treating cold damage in the southern regions. When the syndrome manifests in the Yangming channel, Ephedrae Herba (Mahuang, 麻黄) and Cinnamomi Ramulus (Guizhi, 桂枝) are removed from Gan Ge Tang (Puerariae Radix Decoction), renamed Sheng Ma Gan Ge Tang (Cimicifugae Rhizoma and Puerariae Radix Decoction), which possesses a mild, light, and pure flavor. Only for the Shaoyang channel syndrome is Xiao Chai Hu Tang (Minor Bupleurum Decoction) still followed; however, if cold signs predominate, Qiang Huo (Notopterygii Rhizoma et Radix) and Fang Feng (Saposhnikoviae Radix) are doubled, and Huang Qin (Scutellariae Radix) is reduced for treatment. If symptoms appear simultaneously across all three Yang channels, medications are selected by synthesizing the principles of the three channels. Thus, it is said: For aversion to cold and body pain, releasing the exterior is indicated. For painful heaviness in the joints, releasing the exterior is indicated. For headache and stiffness of the neck, releasing the exterior is indicated. For constant coldness of the four limbs, releasing the exterior is indicated. For rigidity and spasms of the four limbs preventing turning over, releasing the exterior is indicated. For red face and body heat with constant coldness of both feet, or a deep and hidden pulse, releasing the exterior is indicated. For constant groaning, weak speech, absence of sweat, and irritability, releasing the exterior is indicated. For the body alternating between lightness and heaviness, with difficulty or ease in turning over, releasing the exterior is indicated. For body pain shifting不定ly between the four limbs and the chest/back, with no fixed location, releasing the exterior is indicated. For feeling chilly as if sprinkled with cold wind and having very hot skin, releasing the exterior is indicated. The above are symptoms of exterior pathogens in the three Yang channels; therefore, the method of releasing the exterior is employed.