六经既叙，仍得而汇言之。先言表里之义，三阳固为表，而太阳非表之表乎？少阳非表
中之
半表里乎？三阴固为里，而太阴非里之表乎？少阴非里之半表里乎？厥阴非里中之里乎？再言经与
脏腑之表里。太阳经与膀胱也，阳明经与胃府也，少阳经与胆府也，非表中之表里乎？太阴
经与脾脏也，少阴经与肾脏也，厥阴经与肝脏也，非里中之表里乎？表里之义得，而汗下之
法可明矣。在表俱可汗，是阴症可汗也。在里俱可下，是阳经可下也。请再言其升降之义，
人之身胸膈居上，心居中之上，腹居中之下，少腹更在下。邪在上，则越之可也。邪在上之
中，则泻之可也。邪在中之下，则下之可也。邪在下，泄之可也。越者升而散之也，泻者徐
而滋之也，下者攻而除之也，泄者就势而推致之也。故除发汗解肌治表之外，又有泻心诸方
，以泻中上之邪；有承气诸方，以下中下之邪；有抵当等汤，以泄少腹在下之邪；外有和解
一方，以治半表里之邪。皆审邪之所在，顺邪之性而治之也，俱不外升降之义也。请再言寒
热虚实之辨，正实则邪必虚，正虚则邪必实，其常也。正虚而邪亦虚，正实而邪亦实，其变也。治其邪实，而必不妨于
正，治其正虚
，而必无助乎邪，方为善治也。热则脉证俱热，寒则脉证俱寒，其真也。热而脉证似寒，寒
而脉证似热，其假也。治其热而必兼顾其阳，治其寒而必兼顾其阴，方为妙法也。其间有寒
热错杂之邪为患者，则又有寒热错杂之治，而救阴救阳之理，愈可明矣。阴盛而阳衰，必驯
至有阴而无阳，此扶阳抑阴，应图之于早也。阳盛而阴衰，必渐成亢阳而亡阴，此济阴和阳
，应识之于预也。阳无而阴不独存，阴亡而阳不狐立，相维则生，相离则死，此又阴阳不可
偏胜之大纲也。明乎此，则《伤寒论》六经之理已尽，而凡病俱可引伸触类，其理无尽矣，
此余之所以再为伸言也乎。
古昔圣贤，治一病必有一主方，千变万化，不脱根本。
在气分者，但行其气，不必病轻药重，攻动其血。在血分者，则必兼平气治，所谓气行
则血随之是也。
大凡体质素虚，驱邪及半，必兼护养元气，(参草之类是也。)仍佐清邪。
暑病首用辛凉，继用甘寒，再用酸泄酸敛，不必用下，可称要言不烦矣。而时下不外发
散消
导，加入香薷一味，或六一散一服。考本草香薷辛温发汗，能泄宿水。夏热气闭无汗，渴饮
停水，香薷必佐杏仁，以杏仁苦降泄气。长夏湿令，暑必兼湿，暑伤气分，湿亦伤气，汗则
耗气伤阳，胃津大受劫烁，变病由此甚多，发泄司令，里真自虚，所以夏月用香薷者宜慎。
春令发痧，从风温湿，夏季从暑风，暑必兼热，秋令从热烁燥气，冬月从风寒(此是秘诀。)
痧本六气客邪，风寒暑湿，必从火化。痧既外发，世人皆云邪透，孰谓出没之际，升必有降
，胜必有复，常有痧外发。身热不除，致咽哑龈腐，喘急腹胀，下痢不食，烦躁昏沉，竟以
告毙者，皆属里症不清致变。须分三焦受邪孰多，或兼别病，须细体认。
上焦药用辛凉，中焦药用苦辛寒，下焦药用酸寒。上焦气味宜轻，肺主气，皮毛属肺之
合，
外邪宜辛胜，里甚宜苦胜。若不烦渴，病日久邪郁不清，可淡渗以泄气分。中焦药痧火在中
，为阳明燥化，多气多血，用药气味苦寒为宜。若日多胃津消烁，苦则助燥劫津，甘寒宜用
。下焦药咸苦为主，若热毒下注成痢，不必咸以软坚，但取苦味，坚阴燥湿。
六经的证候既然已经叙述完毕，现在再综合概括地论述一下。首先阐述表与里的含义：三阳经确实属于表证，但太阳经难道不是表中之表吗？少阳经难道不是表里面的半表半里吗？三阴经确实属于里证，但太阴经难道不是里中之表吗？少阴经难道不是里里面的半表半里吗？厥阴经难道不是里中之里吗？
其次阐述经络与脏腑之间的表里关系。太阳经与膀胱腑相表里，阳明经与胃腑相表里，少阳经与胆腑相表里，这难道不是表中的表里关系吗？太阴经与脾脏相表里，少阴经与肾脏相表里，厥阴经与肝脏相表里，这难道不是里中的表里关系吗？明确了表里的含义，那么发汗和攻下的治法就可以明白了。病邪在表，都可以用发汗法治疗，这就是阴证（此处指病位在表的证候）可以用汗法；病邪在里，都可以用攻下法治疗，这就是阳经病可以用下法。
请再谈谈升降的含义。人的身体中，胸膈位于上部，心脏位于中部的上方，腹部位于中部的下方，小腹部更在下部。邪气在上部，可以用涌吐法升散之；邪气在中部之上，可以用泻心法缓而滋之；邪气在中部之下，可以用攻下法去除之；邪气在下部，可以顺势泄导之。所谓“越”，就是升散的方法；所谓“泻”，就是缓而滋润的方法；所谓“下”，就是攻逐去除的方法；所谓“泄”，就是顺应病势推荡排出。因此，除了发汗解肌以治疗表证之外，还有泻心汤类方剂，用来泻除中上部的邪气；有承气汤类方剂，用来攻下中下部的邪气；有抵当汤等方剂，用来泄除小腹部下部的邪气；此外还有和解剂一方，用来治疗半表半里的邪气。这些都是审察邪气所在的位置，顺应邪气的性质来进行治疗的，都不外乎升降的道理。
请再谈谈寒、热、虚、实的辨别。正气充实则邪气相对虚弱，这是常理；正气虚弱则邪气相对亢盛，这也是常理。正气虚弱而邪气也虚弱，正气充实而邪气也充实，这是变局。治疗邪气实，必须不损伤正气；治疗正气虚，必须不助长邪气，这才是善于治疗。脉象和症状都表现为热的，是真热；脉象和症状表现为寒的，是真寒，这是真象。热证却出现类似寒的脉症，寒证却出现类似热的脉症，这是假象。治疗热证必须兼顾阳气，治疗寒证必须兼顾阴液，这才是妙法。其中如果有寒热错杂的邪气致病，就有寒热错杂的治疗方法，救阴和救阳的道理也就更加明确了。阴气盛而阳气衰，必然逐渐发展到只有阴而没有阳的地步，此时扶助阳气抑制阴气，应当及早谋划。阳气盛而阴气衰，必然逐渐形成孤阳亢盛而阴液亡失，此时济助阴气和调和阳气，应当预先识别。阳气亡失则阴不能单独存在，阴液亡失则阳不能孤立站立，相互维系才能生存，相互分离就会死亡，这又是阴阳不可偏胜的大纲原则。明白了这些，《伤寒论》中六经的道理就穷尽了，凡是疾病都可以由此引申触类旁通，其中的道理是无穷无尽的，这就是我再次详细阐述的原因。
古代的圣贤，治疗一种疾病必定有一个主方，无论千变万化，都不脱离根本。病在气分的，只行气即可，不必因为病情轻而用药过重，去攻动血分。病在血分的，则必须兼治气，这就是所谓“气行则血随之”的道理。
大凡体质素来虚弱的人，在驱除邪气到一半时，必须兼以护养元气（如人参、甘草之类），同时佐以清解邪气。
暑病开始使用辛凉药物，接着使用甘寒药物，再用酸味药泄热或收敛，不需要使用攻下法，这可以说是简要而不繁琐的要诀。然而时下医家不外乎使用发散消导之法，加入一味香薷，或者服用一服六一散。考察本草记载，香薷性味辛温能发汗，能排泄宿水。夏季热气闭塞无汗，口渴饮水导致停水，香薷必须佐以杏仁，因为杏仁苦降泄气。长夏时节湿气当令，暑邪必然兼夹湿邪，暑邪伤气分，湿邪也伤气，发汗则会耗气伤阳，胃中津液大受煎熬劫夺，变生许多疾病。发泄时令之中，体内真元自然虚弱，所以夏季月份使用香薷应当谨慎。
春季发生的痧疹，多从风温湿邪而来；夏季多从暑风而来，暑邪必然兼夹热邪；秋季多从热烁燥气而来；冬季多从风寒而来（这是秘诀）。痧疹本是六气客邪所致，风寒暑湿，必然从火化。痧疹既然向外发出，世人都说是邪气透出，殊不知在出没之际，升发必有下降，胜复必有制约，常有痧疹外发后，身热不退，导致咽喉嘶哑牙龈腐烂，气喘急促腹胀，下痢不能进食，烦躁昏沉，最终死亡的案例，这都是因为里证不清导致病变。必须分辨三焦受邪哪个部位较多，或者兼有其他疾病，需要仔细体认。
上焦用药宜用辛凉，中焦用药宜用苦辛寒，下焦用药宜用酸寒。上焦药物的气味宜轻，肺主气，皮毛属于肺的外合，外邪适宜用辛味胜之，里证严重适宜用苦味胜之。如果不烦渴，病程日久邪气郁结不清，可以用淡渗药物以泄气分之邪。中焦的药，痧火在中，属于阳明燥化，多气多血，用药气味以苦寒为宜。如果日子久了胃津被消烁，苦味会助燥劫津，应当使用甘寒药物。下焦的药物以咸苦为主，如果热毒下注成为痢疾，不必用咸味软坚，只要取苦味，以坚阴燥湿。
Having described the Six Channels (Liu Jing), we now summarize them comprehensively. First, let us discuss the meaning of Exterior and Interior. The Three Yang channels indeed belong to the Exterior, but is not Taiyang (Greater Yang) the exterior of the exterior? Is not Shaoyang (Lesser Yang) the half-exterior/half-interior within the exterior? The Three Yin channels indeed belong to the Interior, but is not Taiyin (Greater Yin) the interior of the exterior? Is not Shaoyin (Lesser Yin) the half-exterior/half-interior within the interior? Is not Jueyin (Terminal Yin) the interior of the interior?
Secondly, let us discuss the exterior-interior relationship between the Meridians and the Zang-Fu organs. The Taiyang Meridian relates to the Bladder Fu organ; the Yangming Meridian relates to the Stomach Fu organ; the Shaoyang Meridian relates to the Gallbladder Fu organ. Are these not the exterior-interior relationships within the exterior? The Taiyin Meridian relates to the Spleen Zang organ; the Shaoyin Meridian relates to the Kidney Zang organ; the Jueyin Meridian relates to the Liver Zang organ. Are these not the exterior-interior relationships within the interior? Once the meaning of exterior and interior is understood, the methods of sweating (Han Fa) and purging (Xia Fa) can be clarified. If the pathogen is in the exterior, sweating can be applied to all cases; this means that syndromes located in the exterior can be treated with sweating. If the pathogen is in the interior, purging can be applied to all cases; this means that Yang channel diseases can be treated with purging.
Let us further discuss the principle of ascending and descending. In the human body, the chest and diaphragm are located superiorly; the Heart is located superiorly in the middle; the abdomen is located inferiorly in the middle; the lower abdomen is even more inferior. If the pathogen is in the upper part, it can be dispersed by emesis (Yue). If the pathogen is in the upper-middle part, it can be drained by clearing the Heart (Xie). If the pathogen is in the lower-middle part, it can be purged downward (Xia). If the pathogen is in the lower part, it can be drained along its course (Xie). "Yue" refers to ascending and dispersing; "Xie" refers to draining slowly and moistening; "Xia" refers to attacking and removing; "Xie" refers to pushing out along the momentum. Therefore, besides using sweating and releasing the muscle layer to treat the exterior, there are formulas such as Xie Xin Tang (Drain the Epigastrium Decoction) to drain pathogens in the middle-upper part; Cheng Qi Tang (Order the Qi Decoction) variants to purge pathogens in the middle-lower part; Di Dang Tang (Resist the Blood Decoction) variants to drain pathogens in the lower abdomen; and additionally, a Harmonizing formula to treat half-exterior/half-interior pathogens. All these involve examining the location of the pathogen and treating according to its nature, adhering to the principle of ascending and descending.
Let us further discuss the differentiation of Cold, Heat, Deficiency, and Excess. When Zheng Qi (Upright Qi) is solid, the pathogen must be weak; when Zheng Qi is deficient, the pathogen must be strong; this is the normal pattern. When Zheng Qi is deficient and the pathogen is also weak, or Zheng Qi is solid and the pathogen is also strong, this is the variable pattern. To treat pathogenic excess, one must not harm Zheng Qi; to treat Zheng Qi deficiency, one must not aid the pathogen; only then is it good treatment. When pulse and symptoms both present heat, it is true heat; when pulse and symptoms both present cold, it is true cold; this is the true presentation. When a heat syndrome presents with cold-like pulse and symptoms, or a cold syndrome presents with heat-like pulse and symptoms, this is a false presentation. To treat heat, one must simultaneously consider Yang; to treat cold, one must simultaneously consider Yin; only then is it a subtle method. Among these, if the disease is caused by mixed cold and heat pathogens, there are treatments for mixed cold and heat, making the principles of saving Yin and saving Yang even clearer. When Yin is excessive and Yang is declining, it will inevitably evolve into a state of having Yin without Yang; thus, supporting Yang and suppressing Yin should be planned early. When Yang is excessive and Yin is declining, it will gradually become hyperactive Yang leading to the loss of Yin; thus, nourishing Yin and harmonizing Yang should be recognized in advance. Without Yang, Yin cannot exist alone; without Yin, Yang cannot stand alone. Mutual maintenance leads to life; separation leads to death. This is the general principle that Yin and Yang must not prevail excessively. Understanding this, the principles of the Six Channels in Shang Han Lun (Treatise on Cold Damage) are exhausted, and all diseases can be extended and categorized from this, with endless principles. This is why I elaborate again.
In ancient times, sages and worthies had a principal formula for each disease. Regardless of thousands of variations, they did not deviate from the root. For conditions in the Qi level, one merely regulates Qi; there is no need for heavy medication to attack the Blood level just because the illness seems light. For conditions in the Blood level, one must simultaneously regulate Qi, as stated: "When Qi moves, Blood follows."
Generally, for patients with constitutionally weak bodies, when expelling pathogens halfway, one must simultaneously protect Yuan Qi (Primordial Qi) (such as Ren Shen (Ginseng Root) and Gan Cao (Licorice Root)), while assisting in clearing the pathogens.
For Summerheat diseases, one first uses Acrid-Cool herbs, then Sweet-Cold herbs, followed by Sour-draining or Sour-astringent herbs. Purging is unnecessary. This can be called essential words without verbosity. However, contemporary practitioners mostly use dispersing and guiding-out methods, adding one herb of Xiang Ru (Moslae Herba) or taking Yi Liu San (Six-Ingredient Powder). Examining the Materia Medica, Xiang Ru is Acrid-Warm, induces sweating, and can drain retained water. In summer, when heat closes pores causing anhidrosis, thirst, and drinking leading to water retention, Xiang Ru must be combined with Xing Ren (Armeniacae Semen Amarum), because Xing Ren is Bitter and descends/drains Qi. In late summer when Dampness prevails, Summerheat must combine with Dampness. Summerheat damages the Qi level, and Dampness also damages Qi. Sweating consumes Qi and injures Yang, greatly depleting Stomach Jin Ye (Body Fluids), leading to many complications. During the season of dispersal, the internal True Yuan is naturally deficient; therefore, the use of Xiang Ru in summer months should be cautious.
Sha Zhen (Miasma Rash) occurring in Spring arises from Wind-Warmth-Dampness; in Summer from Summerheat-Wind (Summerheat always combines with Heat); in Autumn from Heat-Burning-Dryness; in Winter from Wind-Cold (this is a secret). Sha originates from the six climatic factors invading pathogens. Wind, Cold, Summerheat, and Dampness must transform into Fire. Once Sha erupts externally, people say the pathogen has penetrated. Who realizes that at the time of emergence and disappearance, ascending must have descending, and prevailing must have reacting? Often, after Sha erupts externally, body heat persists, leading to hoarseness, gingival rot, panting, abdominal distension, dysentery, inability to eat, irritability, lethargy, and eventually death. These are all due to unclear Interior syndromes causing changes. One must distinguish which Jiao (Burner) suffers more from the pathogen, or if other diseases are concurrent, requiring careful discernment.
Medicines for the Upper Jiao should be Acrid-Cool; for the Middle Jiao, Bitter-Acrid-Cold; for the Lower Jiao, Sour-Cold. Medicines for the Upper Jiao should have light flavors. The Lung governs Qi, and skin/hair belongs to the Lung's exterior combination. External pathogens are best overcome by Acrid flavors; severe Interior conditions are best overcome by Bitter flavors. If there is no irritability or thirst, and the disease has lasted long with stagnant pathogens unclear, one can use Light-Perculating herbs to drain the Qi level. For Middle Jiao medicines, Sha fire is in the middle, belonging to Yangming Dryness transformation, characterized by abundant Qi and Blood; thus, Bitter-Cold flavors are suitable. If days pass and Stomach fluids are depleted, Bitter flavors will aid dryness and deplete fluids; Sweet-Cold should be used. For Lower Jiao medicines, Salty-Bitter is primary. If Heat-Toxin flows downward becoming dysentery, there is no need for Salty to soften hardness; simply take Bitter flavors to firm Yin and dry Dampness.