夫春温、夏热、秋燥，所伤皆阴液也。苟能时时预护，处处堤防，岂复有精竭人亡之虑？伤寒所伤者，阳气也。诚
能保护得法，自无寒化热而伤阴，水负火而难救之虞。即使有受伤处，临证者知何者当护阳，何者当救阴，何者当先护
阳，何者当先救阴，因端竟委，可备知终始，而超妙道之神。
湿伤脾阳，在中则不运痞满，传下则洞泄腹痛。伤胃阳，则呕逆不食，膈胀胸痛。两伤脾胃，既有脾证，又有胃证
也。其伤脾胃之阴若何？湿久生热，热必伤阴，古称湿火者是也。伤胃阴，则口渴不饥；伤脾阴，则舌先灰滑，后反黄
燥，大便坚结。湿为阴邪，其伤人之阳也，得理之正，故多而常见；其伤人之阴也，乃势之变，故罕而少见。治湿必须
审在何经何脏，兼寒兼热，气分血分，而出辛凉、辛温、甘温、苦温、淡渗、苦渗之治。否则笼统混治，将见肿胀、黄
疸、洞泄、衄血、便血诸症蜂起矣。盖土为杂气，兼证甚多，最难分析，岂可泛论湿气而已哉？
湿温一证，盖土为杂气，寄旺四时，藏垢纳污，无所不受，其间错综变化，不可枚举。其在上焦也如伤寒，其在下
焦也如内伤，其在中焦也如外感，或如内伤。至人之受病也，亦有外感，亦有内伤，使人心摇目眩，无从捉摸。其变证
也，则有湿痹、水气、咳嗽、痰饮、黄汗、黄瘅、肿胀、疟痢、淋带、便血、痔疮、疝气、痈脓等证，较之风、火、燥、
寒四门之中，倍而又倍。苟非条分缕析，体贴入微，未有不张冠李戴者。
春季的温病、夏季的热病、秋季的燥病，所损伤的都是人体的阴液。如果能够时时预先保护，处处加以防范，哪里还会有精气枯竭、人亡命绝的忧虑呢？伤寒所损伤的是人体的阳气。如果确实能够保护得当，自然就没有寒邪转化为热邪而损伤阴液，导致水不胜火、难以救治的担忧了。即使有受伤的地方，临证医生知道哪些情况应当保护阳气，哪些情况应当救阴，哪些情况应当先护阳，哪些情况应当先救阴，从起因到结果全面掌握，就可以知晓疾病的始终，从而达到神妙高超的境界。
湿邪损伤脾阳，在体内中焦则导致运化失常、痞塞胀满；传变至下焦则导致腹泻如注、腹痛。损伤胃阳，则出现呕吐逆气、不能进食、胸膈胀满、胸痛。脾胃同时受伤，既有脾的病证，又有胃的病证。那么湿邪损伤脾胃之阴又是怎样的呢？湿气久留而生热，热邪必然损伤阴液，古人称之为“湿火”。损伤胃阴，则出现口渴但不想吃东西；损伤脾阴，则舌苔先呈灰滑色，后来反而转为黄燥，大便坚硬结聚。湿属于阴邪，它损伤人的阳气，符合正常的规律，所以多见且常见；它损伤人的阴液，则是形势的变化，所以罕见且少见。治疗湿病必须审察是在哪条经络、哪个脏腑，兼夹寒邪还是热邪，涉及气分还是血分，从而采用辛凉、辛温、甘温、苦温、淡渗、苦渗等治法。否则笼统地混合治疗，将会看到肿胀、黄疸、腹泻不止、鼻出血、便血等各种病症蜂拥而起。因为土（脾胃）对应杂气，兼夹证候非常多，最难分析，怎么能仅仅泛泛谈论湿气罢了呢？
湿温这一类病证，大概是因为土为杂气，寄居旺盛于四季之中，藏污纳垢，无所不受，其中的错综变化，不可胜数。它在病位在上焦时，表现如同伤寒；在下焦时，如同内伤；在中焦时，如同外感，或者像内伤。至于人患病的原因，也有外感因素，也有内伤因素，使人心中动摇、目眩，无从捉摸。它的变证，则有湿痹、水气、咳嗽、痰饮、黄汗、黄疸、肿胀、疟疾痢疾、淋浊带下、便血、痔疮、疝气、痈脓等证候，比之风、火、燥、寒四门中的病证，多了一倍又一倍。如果不是条分缕析，体贴入微，没有不张冠李戴搞错情况的。
Spring warm diseases, summer heat diseases, and autumn dryness diseases all injure the body's Yin fluids. If one can constantly guard against them in advance and prevent them everywhere, how could there be any worry of essence depletion and death? Shanghan (Cold Damage) injures Yang Qi. If protection is indeed methodical, there will naturally be no fear of cold transforming into heat and injuring Yin, leading to a situation where Water fails to control Fire, making rescue difficult. Even if injury occurs, the clinician should know which cases require protecting Yang, which require saving Yin, which require prioritizing Yang protection, and which require prioritizing Yin rescue. By understanding the beginning and end thoroughly, one can grasp the entire course of the disease and attain a divine level of mastery.
Dampness injures Spleen Yang; when located in the Middle Jiao, it causes failure of transportation and transformation, resulting in fullness and obstruction; when transmitting to the Lower Jiao, it causes profuse diarrhea and abdominal pain. Injuring Stomach Yang leads to vomiting, regurgitation, anorexia, chest diaphragm distension, and chest pain. When both Spleen and Stomach are injured, there are both Spleen symptoms and Stomach symptoms present. How does dampness injure the Yin of Spleen and Stomach? Prolonged dampness generates heat, and heat inevitably injures Yin; this is what the ancients called "Damp-Fire." Injuring Stomach Yin results in thirst without appetite; injuring Spleen Yin results in the tongue first appearing gray and slippery, later turning yellow and dry, with hard, constipated stools. Dampness is a Yin pathogen; its injury to human Yang follows the normal principle, so it is common and frequently seen; its injury to human Yin is a variation of circumstances, so it is rare and seldom seen. Treating dampness requires examining which meridian and zang-fu organ are involved, whether it is complicated by cold or heat, and whether it affects the Qi level or Blood level, thereby employing treatments such as Acrid-Cool, Acrid-Warm, Sweet-Warm, Bitter-Warm, Light-Permeating, and Bitter-Permeating methods. Otherwise, treating indiscriminately will lead to a swarm of symptoms such as swelling, jaundice, profuse diarrhea, epistaxis, and hematochezia. Since Earth corresponds to miscellaneous qi and has many complicated syndromes, it is the most difficult to analyze; how can one merely discuss dampness in general terms?
The syndrome of Damp-Warmth arises because Earth is miscellaneous qi, flourishing during all four seasons, harboring filth and accepting pollution, receiving everything without exception. Its intricate changes cannot be enumerated. When located in the Upper Jiao, it resembles Shanghan (Cold Damage); when in the Lower Jiao, it resembles Internal Injury; when in the Middle Jiao, it resembles External Contraction or Internal Injury. Regarding the cause of illness in humans, there are external contractions and internal injuries, causing mental confusion and dizziness, making it impossible to grasp. Its transformed syndromes include Damp-Bi (painful obstruction), water retention, cough, phlegm-fluids, yellow sweat, jaundice, swelling, malaria and dysentery, strangury and leukorrhea, hematochezia, hemorrhoids, hernia, and carbuncle-pus. Compared to the categories of Wind, Fire, Dryness, and Cold, these are doubled and redoubled. Unless one analyzes meticulously and understands every detail, one will inevitably misidentify the condition.