湿有内外之殊。外感则入经络而流关节。内伤则由脏腑而归脾肾。湿为土
气。土居水火之中。水阴而火阳。阴阳交感。水火相蒸则生湿气。火盛则湿化为热。水盛则湿
化为饮。湿热者治以辛凉。湿寒者治以辛温。（入腑脏者行其水道入经络者开其汗孔）
南方之地。其气不正。阴常盛。春夏多寒。阳恒泄。秋冬多热。阳外而阴内。阳浮而阴闭。
故人得病多内寒外热。下寒上热。医者不察。概用升阳发表等药。致病者痰滞神昏。而不知人。
服多者气逆。哕而汗出即逝。盖瘴病之作。秋冬为多。人之阳气。春升夏浮。秋降冬藏。秋冬热。
是行夏浮之令。而秋冬之令不行。阳气之不降也明矣。阳气不降。则中下二焦空虚而寒。大法升
降浮沉则顺之。寒热温凉则逆之。知此者急使阳气下降。及温中之不暇。而况敢用升浮
凉药以犯逆时之戒乎。凡升阳之药。味辛性凉。味辛便能散真气。性凉非脾胃虚寒所宜。因其升。
故心肺之阳不降。所以神愈昏不知人。因其散气。故中气愈虚。不能运痰。所以痰滞。因其性凉。
脾胃愈寒。所以发哕。因其发汗。故汗一出翻然作冷。上焦几微之间。气随汗而出。所以即逝。
议论至此。治瘴者。岂可以升阳风药而妄用之哉。所谓升阳风药者。如升麻。防风。荆芥。羌活。独活。
前胡。薄荷。天麻。蔓荆。葛根。细辛。白芷。川芎。紫苏之属是也。余观今之医瘴者。不识其端。
妄以头痛发热。身痛口渴。为时行寒疫。用败毒散及升阳散火汤二三服。则痰滞不语。目瞪口噤。
元气素实者。热退时此症亦退而苏。热来时其症复来。此时急宜温中利痰。用治瘴正法。多有得生者。
若元气虚。服三四服即变 瘴。七日外竟成大梦。又有一等元气极实者。服前药亦不痰滞。亦不变 。
止是热不退。直至十四日内热微时。方作哕而逝。此等变症不惟败
毒散火汤。虽参苏饮变症亦如此。
湿邪有内湿与外湿的区别。外感湿邪则侵入经络并流注于关节；内伤湿邪则由脏腑病变最终累及脾肾。湿属于土气，土居于水与火之间。水性阴而火性阳，阴阳相互交感，水火相互蒸腾便产生湿气。若火气偏盛，则湿气转化为热邪；若水气偏盛，则湿气转化为饮邪。治疗湿热证宜用辛凉之法，治疗湿寒证宜用辛温之法。（对于湿邪入腑脏者，应通利水道；对于湿邪入经络者，应开启汗孔以发汗解表）
南方之地，气候不正，阴气常盛，春夏季节多寒冷；阳气恒常耗泄，秋冬季节多炎热。阳气浮越于外而阴气闭郁于内，阳气上浮而阴气闭塞。因此人们患病多为内寒外热、下寒上热之证。医者若不仔细察辨，一概使用升阳发表等药物，会导致患者痰浊停滞、神志昏迷甚至不知人事。服用过多者会出现气机上逆、呃逆（哕）且汗出后随即死亡。大概瘴病的发作，在秋冬季节较多。人的阳气，春季升发，夏季浮越，秋季下降，冬季潜藏。秋冬季节出现热象，是行夏季阳气浮越之令，而秋冬阳气收敛潜藏之令未能正常执行。阳气不能下降的情况是很明显的。阳气不降，则中焦和下焦空虚而生寒。治疗的大法是：升降浮沉方面要顺应病势，寒热温凉方面要逆其病性。懂得这一道理的人，会急于使阳气下降，以及温补中焦都来不及，何况还敢使用升浮性质的凉药来触犯违背时令的禁忌呢？凡是具有升阳作用的药物，味道辛而性质凉。味辛就能发散真气，性质凉就不适合脾胃虚寒的体质。因为药性升提，所以心肺的阳气不能下降，导致神志更加昏沉不知人事。因为药性散气，所以中气更加虚弱，不能运化痰浊，导致痰浊停滞。因为药性寒凉，所以脾胃更加寒冷，导致发生呃逆。因为药性能发汗，所以一出汗身体反而突然发冷。上焦极其微弱的气机随着汗液排出，所以病人随即死亡。议论到这里，治疗瘴病的人，怎么可以滥用升阳风药呢？所谓升阳风药，指的是像升麻、防风、荆芥、羌活、独活、前胡、薄荷、天麻、蔓荆子、葛根、细辛、白芷、川芎、紫苏这一类药物。我观察当今治疗瘴病的医生，不识其根本原因，妄将头痛发热、身痛口渴诊断为时行寒疫，使用败毒散及升阳散火汤二三服后，则出现痰浊停滞、不能言语、两眼直视、口噤不开的症状。元气原本充实的人，热退时这些症状也会消退而苏醒；热来时这些症状又会复发。此时应当急用温中利痰的方法，采用治疗瘴病的正规治法，大多能存活。如果元气虚弱，服用二三服后就会转变为变证，七日之后竟然陷入昏迷如大梦一般。又有一类元气极实的人，服用前述药物也不会出现痰滞或变证，只是热不退，直到十四日内热势轻微时，才发生呃逆而死。这类变症，不仅仅是败毒散和升阳散火汤，即使是参苏饮，产生的变症也是如此。
Dampness differs in its origin as either external or internal. External dampness invades the meridians and flows into the joints; internal dampness originates from the Zang-Fu organs and ultimately affects the Spleen and Kidney. Dampness belongs to the Qi of Earth, which resides between Water and Fire. Water is Yin and Fire is Yang; when Yin and Yang interact and steam each other, dampness is generated. If Fire is excessive, dampness transforms into Heat; if Water is excessive, dampness transforms into Fluid retention (Yin). For Damp-Heat patterns, treatment employs Acrid-Cool methods; for Damp-Cold patterns, treatment employs Acrid-Warm methods. (For dampness entering the Fu organs, promote water passage; for dampness entering the meridians, open the pores to induce sweating.)
In the southern regions, the climate is irregular. Yin Qi is often abundant, making Spring and Summer seasons frequently cold. Yang Qi is constantly depleted, making Autumn and Winter seasons frequently hot. Yang floats outward while Yin closes inward; Yang floats upward while Yin obstructs. Consequently, people often suffer from diseases characterized by internal Cold and external Heat, or lower Cold and upper Heat. Physicians who fail to examine these conditions carefully may indiscriminately use herbs that raise Yang and release the exterior. This can cause phlegm stagnation, clouding of the spirit, coma, and loss of consciousness. Overuse leads to rebellious Qi, hiccups (Yue), profuse sweating, and sudden death. Generally, miasma diseases occur more frequently in Autumn and Winter. Human Yang Qi ascends in Spring, floats in Summer, descends in Autumn, and stores in Winter. The presence of heat in Autumn and Winter indicates the execution of Summer’s floating command, while the proper descending and storing commands of Autumn and Winter fail to operate. It is clear that Yang Qi fails to descend. When Yang Qi does not descend, the Middle and Lower Jiao become empty and cold. The general principle is to follow the trends of ascending/descending and floating/sinking, but oppose the nature of Cold/Heat/Warm/Cool. Those who understand this will urgently seek to make Yang Qi descend and warm the Middle Jiao without delay, let alone daring to use ascending-floating Cool herbs that violate the taboo against opposing seasonal norms. All herbs that raise Yang are Acrid in flavor and Cool in nature. Acrid flavors disperse True Qi; Cool nature is unsuitable for deficiency-cold of the Spleen and Stomach. Due to their ascending property, Heart and Lung Yang cannot descend, causing further clouding of the spirit and unconsciousness. Due to their dispersing property, Middle Qi becomes more deficient, unable to transform phlegm, leading to phlegm stagnation. Due to their Cool nature, the Spleen and Stomach become colder, inducing hiccups. Due to their diaphoretic property, sweating causes sudden chills. The vital Qi in the Upper Jiao, already extremely weak, escapes with the sweat, leading to immediate death. Having discussed this, how can practitioners of miasma disease recklessly use Yang-raising wind herbs? These so-called Yang-raising wind herbs include Shengma (Cimicifugae Rhizoma), Fangfeng (Saposhnikoviae Radix), Jingjie (Perillae Folium processed with ash), Qianghuo (Notopterygii Rhizoma et Radix), Duhuo (Angelicae Pubescentis Radix), Qianhu (Peucedani Radix), Bohe (Menthae Haplocalycis Herba), Tianma (Gastrodiae Rhizoma), Manjingzi (Viticis Semen), Gegen (Puerariae Lobatae Radix), Xixin (Asari Radix et Rhizoma), Baizhi (Angelicae Dahuricae Radix), Chuanxiong (Ligustici Chuanxiong Rhizoma), and Zisu (Perillae Fructus). I observe that contemporary physicians treating miasma fail to recognize the root cause. They recklessly diagnose headache, fever, body pain, and thirst as epidemic cold, administering Baidu San (Decoction to Overcome Toxins) and Shengyang Sanhuo Tang (Decoction to Raise Yang and Disperse Fire) two or three doses. This results in phlegm stagnation, muteness, fixed gaze, and locked jaw. In patients with originally robust Yuan Qi, symptoms subside and the patient recovers when the fever breaks, but recurs when the fever returns. At this stage, urgent treatment should focus on warming the Middle and promoting phlegm resolution using standard miasma therapies, with many surviving. However, in patients with deficient Yuan Qi, two or three doses lead to transformation into a complicated pattern; after seven days, they fall into a coma resembling a deep dream. Another group of patients with extremely robust Yuan Qi may not experience phlegm stagnation or pattern transformation upon taking these herbs, but the fever persists until it subsides slightly within fourteen days, at which point hiccups occur followed by death. Such complications arise not only from Baidu San and Shengyang Sanhuo Tang, but also from Shen Su Yin (Ginseng and Perilla Decoction).