论曰∶此本一方二法。以大便坚，小便自利，去桂也；以大便不坚，小便不利，故加桂
。其
义深奥难明，注家皆不得之。近徐氏《类方》则云桂枝能利小便，又云白术能生肠胃津液，
亦属牵强。绎经意以身疼、脉虚而涩，为表虚挟湿，复以脉浮推得有风，复以不呕明其无里
症，故以桂枝解表之风，附、术解表之湿。其可确指为湿者，全在“不渴”二字上勘出，故
脉涩作阳虚挟湿论也。然果系有湿，必大便溏，小便不利；若大便坚，小便自利，则非湿症
矣。既非湿症，而见身疼、虚涩之脉，是专属阳虚可知。即其脉浮，亦平脉法所谓浮为虚也
，不得再用解表之药，以重虚其阳，故决然去桂，桂去而术、附皆转为温煦阳气之用矣。二
方之别，所以明二症虚实疑似之辨者至矣。
三方皆麻黄、石膏并用，乃表里同治之法也。然石膏虽曰治里，而《本草》亦称其能解
肌。
是三方者，必也表里俱有热，而又拥于上焦者宣之。且其为制也，大青龙汤麻黄六两，石膏
如鸡子大；麻杏石甘汤麻黄四两，石膏八两；越婢汤麻黄六两，石膏八两。是皆石膏重于麻
黄，石膏为主，麻黄为佐，则解热之杈胜。麻黄虽有发散之性，只得于解热中疏其郁滞而已
。性随制变，故仲景用大青龙，必提出“烦躁”二字，而以脉弱恶风戒其误用，以见大青龙
专为烦躁设。于越婢汤则主自汗出，无大热；于麻杏甘石汤则主汗出而喘，无大热。以见二
方专为喘、汗设。烦躁、喘、汗症虽不同，其为上焦热拥则同，故立法亦同。近柯氏琴《来
苏集》，疑麻杏甘石症“汗出而喘无大热；七字为误，欲移“无”字于“汗出”上。其不足
与语仲景化裁之妙用必矣。
论述说：这原本是一个方剂，两种用法。因为大便干硬、小便自利，所以去掉桂枝；因为大便不干硬、小便不利，所以加入桂枝。其中的义理深奥难以理解，历代注解家都没有掌握其真谛。近代徐氏在《类方》中则说桂枝能通利小便，又说白术能生成肠胃津液，这也属于牵强附会。推究经文原意，以身体疼痛、脉象虚而涩，判断为表虚兼夹湿邪，再结合脉浮推断体内有风邪，又通过不呕吐明确没有里证，因此用桂枝解除表部的风邪，用附子、白术解除表部的湿邪。其中可以确切指认为湿邪的关键，全在于“不渴”这两个字上推敲出来，所以将脉涩解释为阳虚兼夹湿邪。然而如果确实是有湿邪，必然大便溏薄、小便不利；如果大便干硬、小便自利，那就不是湿邪病症了。既然不是湿邪病症，却出现身体疼痛、脉象虚涩的表现，这就专门属于阳虚，是可以确定的。即使脉象浮，也是《平脉法》中所说的“浮脉主虚”，不能再使用解表的药物，以免进一步损伤阳气，所以坚决去掉桂枝。桂枝去掉后，白术和附子的作用就转变为温煦阳气了。这两个方剂的区别，用来阐明两种症状虚实疑似之处的辨别，道理已经非常透彻了。
这三个方剂都是麻黄与石膏并用，这是表里同治的方法。然而石膏虽然说是治疗里热，但《本草》中也称述它能解肌。这三个方剂，一定是表里都有热邪，而且郁结在上焦的，所以要宣散它。并且从它们的配伍来看，大青龙汤中麻黄用六两，石膏如鸡蛋大小；麻杏石甘汤中麻黄用四两，石膏用八两；越婢汤中麻黄用六两，石膏用八两。这些都是石膏重于麻黄，以石膏为主药，麻黄为佐药，那么清热的作用就占优势。麻黄虽然有发散的性质，只能借助于清热来疏通其中的郁滞罢了。药物的性质随着配伍的变化而变化，所以张仲景在使用大青龙汤时，必定提出“烦躁”这两个字，并以脉弱恶风来告诫不要误用，以此说明大青龙汤是专门为烦躁症状设立的。对于越婢汤，则主治自汗出、没有大热；对于麻杏石甘汤，则主治汗出而气喘、没有大热。以此说明这两个方剂是专门为气喘、出汗症状设立的。烦躁、气喘、出汗这些症状虽然不同，但它们都是上焦热邪郁结，所以立法原则也是相同的。近代柯琴的《来苏集》，怀疑麻杏石甘汤证中“汗出而喘无大热”这七个字有误，想要把“无”字移到“汗出”前面。这种观点不足以与他谈论张仲景化裁运用的妙处啊。
Commentary states: This originally constitutes one formula with two applications. Because the stool is hard and urination is spontaneous, Cinnamon Twig (Guizhi) is removed; because the stool is not hard and urination is difficult, Cinnamon Twig (Guizhi) is added. The underlying principle is profound and difficult to understand; commentators have all failed to grasp it. Recently, Xu's *Lei Fang* states that Cinnamon Twig (Guizhi) can promote diuresis, and also claims that Atractylodis Macrocephalae Rhizoma (Baizhu) can generate fluids in the intestines and stomach; this is also considered forced reasoning. Examining the intent of the classic, body pain and a deficient and choppy pulse are taken as indications of exterior deficiency with dampness. Furthermore, a floating pulse suggests the presence of wind, and the absence of vomiting clarifies there are no interior syndromes. Therefore, Cinnamon Twig (Guizhi) is used to resolve exterior wind, while Aconiti Lateralis Radix Praeparata (Fuzi) and Atractylodis Macrocephalae Rhizoma (Baizhu) are used to resolve exterior dampness. What can be definitively identified as dampness is entirely deduced from the two characters "no thirst" (bu ke); thus, the choppy pulse is interpreted as Yang deficiency with dampness. However, if there were indeed dampness, the stool would necessarily be loose and urination difficult; if the stool is hard and urination is spontaneous, it is not a dampness syndrome. Since it is not a dampness syndrome, yet presents with body pain and a deficient, choppy pulse, it must specifically belong to Yang deficiency. Even if the pulse is floating, this aligns with the *Ping Mai Fa* which states "floating indicates deficiency." One should not use exterior-resolving medicines again, lest they further damage the Yang; therefore, Cinnamon Twig (Guizhi) is decisively removed. Once Cinnamon Twig (Guizhi) is removed, the functions of Atractylodis Macrocephalae Rhizoma (Baizhu) and Aconiti Lateralis Radix Praeparata (Fuzi) shift to warming and nourishing Yang Qi. The distinction between these two formulas serves to clarify the subtle differences between similar symptoms of excess and deficiency, demonstrating profound reasoning.
All three formulas utilize Ephedrae Herba (Mahuang) together with Gypsum Fibrosum (Shigao), representing a method of treating both the exterior and interior simultaneously. Although Gypsum Fibrosum (Shigao) is said to treat interior conditions, the *Ben Cao* also notes its ability to release the muscle layer. These three formulas address situations where heat exists in both the interior and exterior, and is constrained in the Upper Jiao, requiring dispersal. Regarding their compositions: in Da Qing Long Tang, Ephedrae Herba (Mahuang) is six liang, and Gypsum Fibrosum (Shigao) is the size of a chicken egg; in Ma Xing Shi Gan Tang, Ephedrae Herba (Mahuang) is four liang, and Gypsum Fibrosum (Shigao) is eight liang; in Yue Bi Tang, Ephedrae Herba (Mahuang) is six liang, and Gypsum Fibrosum (Shigao) is eight liang. In all cases, Gypsum Fibrosum (Shigao) outweighs Ephedrae Herba (Mahuang), with Gypsum Fibrosum (Shigao) as the principal herb and Ephedrae Herba (Mahuang) as an assistant, thereby giving precedence to clearing heat. Although Ephedrae Herba (Mahuang) has dispersing properties, it merely helps to unblock stagnation within the process of clearing heat. The nature of herbs changes according to their formulation; thus, when Zhang Zhongjing uses Da Qing Long Tang, he explicitly mentions "restlessness" (fan zao) and warns against misuse in cases of weak pulse and aversion to wind, indicating that Da Qing Long Tang is specifically designed for restlessness. For Yue Bi Tang, the main indications are spontaneous sweating without significant heat; for Ma Xing Shi Gan Tang, the main indications are sweating with wheezing without significant heat. This shows that these two formulas are specifically designed for wheezing and sweating. Although restlessness, wheezing, and sweating are different symptoms, they all involve heat constraint in the Upper Jiao; therefore, the therapeutic principles are the same. Recently, Ke Qin's *Lai Su Ji* suspected that the seven characters "sweating with wheezing without significant heat" in the Ma Xing Shi Gan Tang syndrome description were erroneous and wished to move the character "without" (wu) before "sweating." Such views are insufficient to discuss the subtleties of Zhang Zhongjing's adaptive modifications.