将以施其疗疾之法，当以穷其受病之源。盖疾 之原不离乎阴阳之二邪也，穷此而疗之，厥
疾弗瘳者鲜矣。良工知其然，谓夫风热火之病，所以属乎阳邪之所客，病既本于阳，苟不求其本
而治之，则阳邪滋蔓而难制；湿燥寒之病，所以属手阴邪之所客，病既本于阴，苟不求其本而治
之，则阴邪滋蔓而难图。诚能穷原疗疾，各得其法，万举万全之功可坐而致也。治病必求其本，
见于《素问·阴阳应象大论》者如此。
夫邪气之机，久而传化，其变证不胜其众也。譬如水之有本，故能游至汪洋浩瀚而趋下以渐
大；木之有本，故能荐生茎叶实秀而在上以渐蕃。若病之有本，变化无穷。苟非必求其本而治之，
欲去深感之患，不可得也。
今夫厥阴为标，风木为本，其风邪伤于人也，掉摇而眩转， 动而螈 ，卒暴强直之病生矣。
少阴为标，君火为本，其热邪伤于人也，疮疡而痛痒，暴注而下迫，水液混浊之病生矣。少阳为
标，相火为本，其热邪伤于人也，为热而瞀 ，躁扰而狂越，如丧神守之病生矣。善为治者，风
淫所胜，平以辛凉；热淫所胜，平以咸寒；火淫所胜，平以咸冷。以其病本于阳，必求其阳而疗
之，病之不愈者，未之有也。太阴为标，湿土为
本，其湿邪伤于人也，腹满而身肿，按之而没指，诸痉强直之病生矣。阳明为标，燥金为本，其
燥邪伤于人也，气滞而 郁，皮肤以皴揭，诸涩枯涸之病生矣。太阳为标，寒水为本，其寒邪伤
于人也，吐利而腥秽，水液以澄冷，诸寒收引之病生矣。善为治者，湿淫所胜，平以苦热；燥淫
所胜，平以苦温；寒淫所胜，平以辛热。以其病本于阴，必求其阴而治之，病之不愈者，未之有
也。岂非将以疗疾之法，当以穷其受病之原者哉？
抑尝论之，邪气为病，各有其候。治之之法，各有其要，亦岂止于一端而已？其在皮毛者，
汗而发之；其入里者，下而夺之。其在高者，因而越之，谓可吐也； 悍者，按而收之，谓按摩
也。脏寒虚夺者，治以灸 ；脉病挛痹者，治以针刺；血实蓄结肿热者，治以砭石；气滞痿厥寒
热者，治以导引；经络不通，病生于不仁者，治以醪醴；血气凝泣，病生于筋脉者，治以熨药。
始焉求其受病之本，终焉蠲其为病之邪者，无出于此也。
噫！昔黄帝处于法宫之中，坐于明堂之上，受业于岐伯，传道于雷公，曰∶阴阳者，天地之
道也，纲纪万物，变化生杀之妙，盖有不测之神斡旋宰制于其间也。人或受邪生病，不离于阴阳
也。病既本于此，为工者岂可他求哉？必求于阴阳可也。至真要大论曰∶有者求之，无者求之。
此求其病机之说，与夫求于本，其理一也。（丹溪）
想要施行治疗疾病的方法，应当探究导致疾病的根源。大抵疾病的根源离不开阴阳两类邪气，穷究了这一点再去治疗，很少有不痊愈的。高明的医生知道这个道理，认为风、热、火这类病证，属于阳邪侵袭所致，既然病本于阳，如果不探求其根本而治疗，那么阳邪就会蔓延滋长而难以控制；湿、燥、寒这类病证，属于阴邪侵袭所致，既然病本于阴，如果不探求其根本而治疗，那么阴邪就会蔓延滋长而难以对付。如果能穷究根源来治疗疾病，各得其法，万无一失的功效就可以轻易获得。治病必求其本，在《素问·阴阳应象大论》中就是这样论述的。
邪气致病，时间久了就会传变转化，其产生的变证多得数不清。譬如水有源头，所以能流淌至汪洋浩瀚并逐渐向下变大；树木有根干，所以能不断生出茎叶花果而在上方逐渐繁茂。如果疾病有根本，变化也是无穷无尽的。如果不探求其根本而治疗，想要去除深重的病患，是不可能的。
如今厥阴经以三阴为标，风木为本，风邪伤人，就会产生肢体摇动眩晕、抽搐痉挛、突然强直等病证。少阴经以二阴为标，君火为本，热邪伤人，就会产生疮疡疼痛瘙痒、急泻里急后重、小便浑浊等病证。少阳经以一阳为标，相火为本，热邪伤人，就会产生发热昏闷、烦躁狂乱、神志失控等病证。善于治疗的人，对于风邪过胜，用辛凉之品来平抑；热邪过胜，用咸寒之品来平抑；火邪过胜，用咸冷之品来平抑。因为病本于阳，必须针对阳邪进行治疗，没有不痊愈的。太阴经以三阴为标，湿土为本，湿邪伤人，就会产生腹部胀满身体浮肿、按压凹陷不起、各种痉病强直等病证。阳明经以二阳为标，燥金为本，燥邪伤人，就会产生气机阻滞郁结、皮肤皲裂脱屑、各种干涩枯涸等病证。太阳经以一阳为标，寒水为本，寒邪伤人，就会产生呕吐泄利气味腥臭、小便清冷、各种寒性收引拘挛等病证。善于治疗的人，对于湿邪过胜，用苦热之品来平抑；燥邪过胜，用苦温之品来平抑；寒邪过胜，用辛热之品来平抑。因为病本于阴，必须针对阴邪进行治疗，没有不痊愈的。这难道不是说明治疗疾病的方法，应当探究致病根源的道理吗？
我曾经论述过，邪气致病，各有其征候。治疗的方法，各有其要点，又岂止是一个方面呢？病在皮毛的，用发汗法使其发散；病入里的，用攻下法使其消除。病位高的，顺势采用涌吐法；病势急猛的，采用按摩手法使其收敛。脏腑虚寒正气亏损的，用艾灸治疗；经脉病变出现痉挛痹痛的，用针刺治疗；血实瘀结肿胀发热的，用砭石放血治疗；气滞痿软厥逆寒热往来的，用导引疗法；经络不通、病生麻木不仁的，用酒剂治疗；气血凝滞、病生在筋脉的，用热敷药熨治疗。开始探求致病的根本，最终祛除致病的邪气，方法都不出这些范围。
唉！从前黄帝在法宫之中，坐在明堂之上，向岐伯求学，从雷公那里传承道术，说：阴阳，是天地运行的规律，是万物的纲纪，其中蕴含着变化生死奥妙的精神力量在主宰运作。人如果受邪生病，离不开阴阳。既然病本于此，作为医生怎能去别处寻求呢？必须从阴阳入手才行。《素问·至真要大论》说：有的病要探求其因，无的病也要探求其理。这种探求病机的说法，与探求疾病的根本，道理是一样的。（朱丹溪）
To apply the methods of treating diseases, one must investigate the source of the pathology. Generally, the origin of disease does not depart from the two types of pathogenic factors: Yin and Yang (Yin-Yang). By thoroughly investigating this aspect before treatment, cases where the severe illness (Jue Ji) fails to heal are rare. Skilled physicians understand this principle. They assert that diseases such as Wind (Feng), Heat (Re), and Fire (Huo) belong to the invasion of Yang pathogens. Since the disease originates in Yang, if its root is not sought and treated, the Yang pathogen will spread and become difficult to control. Conversely, diseases such as Dampness (Shi), Dryness (Zao), and Cold (Han) belong to the invasion of Yin pathogens. Since the disease originates in Yin, if its root is not sought and treated, the Yin pathogen will spread and become difficult to manage. If one can thoroughly investigate the origin to treat the disease and apply the appropriate methods, success can be achieved effortlessly. The principle that "treating disease requires seeking its root" is stated thus in *Su Wen: Yin Yang Ying Xiang Da Lun* (Basic Questions: Great Treatise on the Correspondence of Yin and Yang).
When pathogenic factors cause disease, they transform over time, resulting in a multitude of complicated manifestations. For example, water has a source, allowing it to flow into vast oceans and gradually expand downwards; trees have roots, allowing them to continuously produce stems, leaves, and fruits, growing luxuriantly upwards. Similarly, if a disease has a root, its changes are infinite. Without seeking the root to treat it, it is impossible to eliminate deep-seated ailments.
Currently, the Jueyin (Liver/Gallbladder channel system) presents with Wind-Wood as its root and Three Yin as its marker. When Wind pathogen invades the human body, it causes symptoms such as tremors, dizziness, convulsions, and sudden rigidity. Shaoyin (Heart/Kidney channel system) presents with Ministerial Fire (Jun Huo) as its root and Two Yin as its marker. When Heat pathogen invades, it causes sores, ulcers, itching, acute diarrhea with tenesmus, and turbid urine. Shaoyang (Sanjiao/Gallbladder channel system) presents with Associate Fire (Xiang Huo) as its root and One Yang as its marker. When Heat pathogen invades, it causes fever, mental confusion, restlessness, mania, and loss of spiritual control. Competent practitioners treat excessive Wind with pungent-cool substances; excessive Heat with salty-cold substances; and excessive Fire with salty-cold substances. Since these diseases originate in Yang, treating the Yang aspect ensures recovery.
Taiyin (Spleen/Lung channel system) presents with Damp-Earth as its root and Three Yin as its marker. When Damp pathogen invades, it causes abdominal fullness, edema (pitting upon pressure), and various spasmodic rigidities. Yangming (Stomach/Large Intestine channel system) presents with Dryness-Metal as its root and Two Yang as its marker. When Dryness pathogen invades, it causes Qi stagnation, skin cracking and scaling, and various dryness-related conditions. Taiyang (Bladder/Small Intestine channel system) presents with Cold-Water as its root and One Yang as its marker. When Cold pathogen invades, it causes vomiting, purging with foul odor, clear cold urine, and various cold-induced contraction and pulling sensations. Competent practitioners treat excessive Dampness with bitter-hot substances; excessive Dryness with bitter-warm substances; and excessive Cold with pungent-hot substances. Since these diseases originate in Yin, treating the Yin aspect ensures recovery. Is this not proof that treating disease requires investigating its origin?
I have previously discussed that pathogenic factors manifest specific signs, and their treatments have specific key points, extending beyond a single method. For diseases in the skin and hair, use diaphoresis (sweating method) to disperse them; for diseases entering the interior, use purgation to drain them. For diseases located high, use emesis (vomiting method); for fierce/aggressive pathogens, use massage to subdue them. For deficiency-cold of the Zang organs, use moxibustion; for pulse disorders involving spasms and bi-syndrome, use acupuncture; for blood excess with stasis, swelling, and heat, use bian stone (lithotomy/bloodletting); for Qi stagnation, flaccidity, cold limbs, and alternating chills and fever, use Dao Yin (qigong/exercise therapy); for meridian blockage causing numbness, use medicinal wine (Lao Li); for coagulated Qi and Blood affecting sinews and vessels, use hot compresses with herbs. Starting by seeking the root of the disease and ending by eliminating the pathogenic factor, all methods fall within this scope.
Alas! In ancient times, Huangdi sat in the Hall of Laws, receiving teachings from Qibo and transmitting the Way from Leigong. He said: Yin and Yang are the principles of Heaven and Earth, the guidelines for all things, containing the mysterious power of transformation and life-death cycles. When humans contract disease from pathogens, it never departs from Yin and Yang. Since the disease originates here, how can physicians seek elsewhere? They must seek it in Yin and Yang. *Zhi Yao Da Lun* (Great Treatise on the Most Essential) states: "Seek what exists, seek what does not exist." This approach to investigating disease mechanisms aligns with the principle of seeking the root. (Zhu Danxi)