上古圣人视河图以明阴阳之道，五行之理，天地之所以成变化而行鬼神者，要不出此。人身一天地也，则其为生为成者，亦岂外是哉。故天一生水，地六成之，在人身则为肾。地二生火，天七成之，在人身则为心。天三生木，地八成之，在人身则为肝。地四生金，天九成之，在人身则为肺。天五生土，地十成之，在人身则为脾。故人俱阴阳五行，无异于天地，亦无异于河图也。但天地之阴阳五行，往来阖辟，尽其道之自然。人身之阴阳五行，或外为六气所感，内为七情所伤，五行戕贼而病之纷然杂出者，不可胜数矣。然概而论之，其端有二；一在富贵之子深居简出，体无劳倦，而其病即生于饱暖淫欲之中，故外感之气少而内伤之病妥。至内虚而外感亦易入矣，此犹河图之生数有亏而成数亦因之而损也。一在贫贱之人，冲风冒雨，手足勤够，而其病每生于饥寒困苦之间，故内伤之疾少而外感之气多。至外感深则内伤亦因之矣，此犹河图之成数不立而生数难独存也。病虽杂出，而斯二者之相为表里其大概也。是在司命者，因人审疾，察其内外先后，而施治得宜，则人身之阴阳和合，五行顺布，犹之天地河图也。
脾阳合中五说
今夫万物之所以托命者，土也，而五行亦无土不成。故土者后天之根本，而金木水火之枢机也。洛书一图中五称为皇极焉。盖天地太和之气，而万物之所以生长收藏者也。在人身则为脾，内而脏腑，外而肢体百骸之所资养，而气血之所从生也，且水得之而不汜，火得之而不炎，木得之而畅茂，金得之而坚凝，况饮食入胃，得脾为之健运，则清者由是而上升，浊者由是而下降。脾土一伤，则一身之枢机不灵，而百体皆困矣。经云：有胃气则生，无胃气则死。盖言土为后天资生之本，而即洛书之中五也。夫中五阳也，病则不能运，因之上有中满腹胀不食等证，病则不能化，必至下有泄泻下痢清谷等证，皆五土之失职也。故仲景有建中、理中之制，他如四君、六君子诸方，所以培中五建皇极之意也。夫或曰脾土属阴，何以为洛书之中五曰脾土体阴而用阳者也。其质虽阴，而其健运之机则阳也，非洛书之中五而何?
龙雷相火辨
《医贯》有龙火雷火之说，喻人身虚火上炎，得水则炽，不知其性而水折之，适足以光焰烛天，穹物方止。识其性而以火逐之，则炎灼自消也。后世景岳、冯氏莫不附和其议，不知其说则是而取，譬而非也。夫龙雷乃天地蒸郁之火，阴随阳发之象也。阴随阳发，而阳复为阴气所抑，郁则阴阳相争，搏而成声，辄为电矣。此龙雷之所以作也。然当炎夏之时，其阳必胜，其阴必负，阳胜阴负则其气伸散。故一时浓云骤雨，得雷奋风散而蒸郁之火豁然解矣。此犹人身外为风邪闭塞，邪热拂郁，头痛恶寒，轻则必用麻桂等汤，重则必用青龙白虎，外发其汗。内清其热，而邪由是退也。然则龙雷可以譬人身之实火，而不可以譬人身之虚火明甚。夫人身之所以虚火上炎者，皆由于真阴之不足也。真阴者，离中之一阴也，离火体阳而根阴，故离阳虽升，离阴必降。真阴亏则不能下降，而下交于坎，而坎之阴亦亏，坎根阳者也。坎阴亏则坎中之阳无所附而飞越，惟参附八味等剂热药冷饮，乃能引而归之，此犹天地九月之候，以阴剥阳，阳气外越，将为纯阴之卦，必急求一阳来复，庶可二阳三阳开泰，以复其初也。故参附八味之回阳，即大易来复之意，而岂龙雷得水则炽，得火则灭之验哉。
天根月窟说
康节诗云：天根月窟间来往三十六宫，都是春，诚以人身之真阴真阳上下相交循还不息也。盖天根者，坎中之一阳也。即复卦之初九也。有此一阳而三之木、七之火、九之金、莫不始此焉，故不曰天而曰天根，以见阳之所从生也。月窟者，离中之一阴也，姤卦之初六也，有此一阴而四之金、六之水、八之木，莫不肇此焉。故不曰月而曰月窟。以见阴之所由始也。斯二者在天地则为日月，故日往则月来，来往不息而天地始成。其为天地也，于人身为心肾，子半而肾阳上通于心，午半而心阴下交于肾，其气之一呼一吸而往来不穷者，此人之所以生也。然此往也来也，日月之往来，天地以无心而成化也，心肾之往来，至人以有心而无为也。故邵子下一间字，以见自然而然，无所矫强，故往来虽似不间，而实行所无事，俊人不识此理，心多妄动，而真阴渐耗，肾因纵欲而真阳亦亏，甚至水火不交，反泰为否，其原总由水火失职，不相往来耳。故丹溪、东垣辈执阳常有余、阴常不足之论，专以滋阴抑火为治，其见固偏于阴，而未识阴阳，直至赵氏始指命门为坎中真阳，而景岳、冯氏力宗其说，俱以真阳为重，但犹未识真阴在离而偏于阳，其流弊与丹溪、东垣等，此皆由于未识天根月窟之义也。今特以邵子诗而为之解，以明人身之阴阳互根。其往来不息者，实与天地之道吻合，不得以一人之意见妄为轻重于其间也。
论饮大纲
饮者，水气也。身中有饮，犹地中有水。地非水不能灌溉万物，人非饮不能滋润百骸。但地中之水流行则为泉为潮，长发万物，壅塞则停污，横决则泛滥，反为万物之害矣。身中之饮，运行则为津为液，滋养百骸，瘀滞则胀满，逆行则呕吐，反为百骸之病矣。然水之所流行者，土中之阳为之也，阳衰则泛滥，阳郁则停污。饮之所以运行者，脾中之阳为之也。阳衰则胀满，阳郁则呕吐。故经云：太阴所至为积饮，否隔畜满。又云：中满腹大，其发濡滞，诚以太阴所至纯是湿土用事，湿甚则阴衰，不能为胃行其津液，又不能散精上归于肺。饮与湿合，遂随经横流而病成矣。然湿性就下，虽有五脏留伏之不同，未有不本于脾者也。随脾经而下决小肠，丙火搏击于内，以至沥沥有声，谓之痰饮，犹水之畜积，沟渠郁蒸而败浊也。随脾经而旁决于少阳，阻抑左旋之道，以致咳唾引痛，谓之悬饮。犹水之壅过高原而为悬河也，随脾经而外决四肢，郁于皮毛，肌肉，当汗出而不汗出，以至身体疼痛，谓之溢饮，犹水之不归河道，汪洋四出而为洚水也。随脾经而上决于胸中，阻其宗气，致短气不得卧，以至其形如肿，谓之支饮，犹水之不趋汀海，别开一迳而为支河也。总之饮为阴体，以阳为用，阳衰则失其所用而饮愈甚。饮甚则害其所用而阳愈困。故水在心则心之阳受困，不能传化于小肠，致坚筑短气。水在肺则肺之阳受困，不能传化于大肠，致吐涎沫。水在脾则脾之阳受困，不能传化于胃，致少气身重。水在肝则肝之阳受困，不能传化于胆，致胁满嚏痛。水在肾则肾之阳受困，不能传化于膀胱，致心下悸。五脏之阳一亏，皆足以为害。而所以统摄渚经之水者，尤当专责其中州。盖阳盛则土足以制水，阳衰则水反足以侮土，使不早维昏垫之灾，急思奠安之法，始而伤于在表之阳，继而伤于在里之阳，始而伤于五脏之阳，继而伤于胸中之阳，几何不横流四决，神州陆沉者哉！
痰 饮 辨
痰与饮虽同出一源，面变现各别。痰为火化，因热而浊，饮为水积，因寒而清。余细绎《内经》，止有积饮、溢饮、悬饮等症。凡论饮证中绝无一说及痰者。惟《金匮》中有痰饮之说，然与溢饮、悬饮、支饮、留饮、伏饮数条并列，亦不过就饮证中推出有痰症耳，未尝指饮症皆属于痰也。后人以饮为痰，溷为一证，千百年来无不沿习其误，以致一切饮症认作痰治，百无一效。虽丹溪之明哲，犹有百病皆痰之论，此等大纲，可不条分而缕析之哉夫痰与饮实有阴阳之分，水火之别，断断不可混淆者。即以痰饮二字之义揣之，痰字从火从炎，皆火之为病，阳也。虽有劳瘵等证，咳嗽吐痰，病实虚寒，然根究其源，亦必阴虚火炽，相火上升所致。其余显然属火者，夫人知之，兹不赘及。凡水皆可曰饮，酒亦曰饮，饮者，其物之濡柔者也。病谓之饮，必因其脾阳困败，土衰不能生金，清肃不行，水精不能四布，因而留伏于经络，横决于四肢，非若痰之胶稠凝结可比。即伤寒中之水气，亦是饮中之一证也。如此分别，泾渭了然，而治法亦迥异矣。
留饮伏饮论
留伏二义，《金匮》论之最详。嘉言先生谓留饮者，留而不去，留饮去而不尽，则名伏饮。伏者，伏而不出也。究竟留伏二字未有分别。余按：留饮全属于水，因五脏阳衰之处而得据其间。伏饮则平素痰气内结，先已暗损胸中之阳，水饮外入，挟痰而伏匿于大气难到之所，流注于中州要害之地，随经深藏结穴，阻抑阳气上升之路，较之留饮更胜十倍矣。再以《金匮》文义细详之，其言留饮者五，伏饮者一。一曰心下有留饮，其人背恶寒，冷如掌大。夫心下者，胃脘之上也。背为胸之府，水饮留止于心下，不特胃脘之阳不振，而督脉之阳亦衰。况胃之俞穴各开一寸五分，上下各离一寸，恰如掌大，故独此处恶寒，此饮之留于心而征于背者也。一曰留饮者，心下痛引缺盆，咳嗽则转甚，言水饮留止胁下，胁下为厥阴少阳专主之地，况少阳之脉由缺盆过季胁，上出肺络，水饮偏阻，生气不达，故吊引缺盆而痛，咳则转甚，此饮之留于胁而征于经络者也。一日胸中有留饮，其人短气而渴，四肢历节痛。夫胸中者，枢机开发之所也，水饮留于胸中，开发之机不利，阳气阻遏于上，故气短而渴，阴寒凝滞于下，不能宣达四肢，故历节作痛，此饮之留于胸而征于上下四旁者也。一日脉沉者，有留饮，言水饮内郁，脉必失其阳和发越之象，此饮之留于经而征于脉者也。一日病者脉伏，其人欲自利，利反快，心下续坚满，此为留饮欲去故也。言脉伏不显，水精填塞，窍随胃气不得转输，自利则水似有去路，而仍续坚满，通而复积，有欲去而不去之势，此饮之留于胃口而征于去就无常者也。至伏饮，则曰膈上病，痰满喘咳，吐发则寒热背痛，腰疼，目泣自出，其人振振自（目闰）而剧，必有伏饮，言胸中乃阳气所治，水邪挟饮而伏匿之，阻遏手足阴阳升降之路，吐发则阴阳相乘而寒热，阳乘阴而郁于下，背痛腰疼，阴乘阴而逆于上，目泣自出，阴阳交争，内外相并，一若伤寒病之振振身（目闰）而剧，此饮之伏于膈上而征于时作时止者也。观《金匮》留饮五条，证虽不同而源则一。一因督脉之阳不伸，一因卫外之阳不伸，总由一经阳气不伸之处而留止也。若伏饮则尤甚焉。凡手足三阳皆为阻遏，故留饮尽属水而常主于动，伏饮兼有痰而有时则静，留饮尚有驱逐之法，伏饮但有温和之法。虽不立方，而轻重缓急，从可类推矣。
饮证属阳虚论
按：饮证数条，《内经》《金匮》皆责之太阴，吾故曰脾阳不足，积水停污所致也。而嘉言云：饮因于湿，有热有寒。言虽近理，实则模糊，不得不为之辨。天地江淮河汉，水行地中，振而不泄者，皆大气为之包举。人身之水注于经络，贯乎百骸，泽于皮毛，皆脾气为之摄运，苟中宫之阳一败，非泛滥则停污矣。即有湿热郁蒸，变而为败浊者，似属元阳为害，不得概指为寒然。讵知其为阳气困极，虚阳脱于外乎譬诸沟渠之水积而不流，有经寒冱而凝结者，有经烈日而秽浊者。经寒冱而凝结者，地之阳气不通于外也。经烈日而秽浊者，地之阳气尽浮乎外也。均谓之阳虚可也。然则饮症之属寒也，可知矣乎夫。
痰饮悬饮溢饮支饮论
饮之为患，《内经》独主于脾，以脾为至阴之脏而不至阳之用，且与胃相为表里。胃为水谷之海，水谷入胃，全赖脾阳为之运化，故脾有一分之阳，能消一分之水谷，脾有十分之阳，能消十分之水谷。水谷过多，则胃中之阴胜于脾中之阳，始也饮自外入而不消，继也饮自内生而益甚，不特伤脾中之阳，并伤心肺肝肾之阳。《金匮》统四纲以正其名，分五经以畅其治，无不从一源而出。一曰痰饮，有火炎之象，以其人素盛今瘦，肌肉消化为痰，心气阻遏，下迫水饮而沥沥有声，必至坚筑短气。一曰悬饮，有倒悬之象，以饮后水流胁下，附于募原隔膜之间，肝气内结，咳嗽则吊胁作痛，自必胁下支满。一日溢饮，有横散之势，以饮水流行，达于四末，肺气不宣，郁于皮毛而不汗出，自必上泛而吐涎沫。一曰支饮，有旁开之象，以其形如肿，中宫失其健运，脾气内郁而至倚息不得卧，自必少气身重。至于水在肾，心下悸，即是痰饮之一证。观伤寒门中水饮在心，心下满而悸，虽见证略有差别，而治法则一。盖以肾水最易凌心也。故仲景即于四饮之中分括五脏，非以四饮之外另有所谓五饮也。后人不察《金匮》之义，妄生五饮六证之说。海藏于五饮汤下云：一留饮在心下，二支饮在胁下，三痰饮在胃中，四溢饮在膈上，五悬饮在肠间。不必问其论症之失，即其论五饮所注之部位已背乱经旨极矣。况欲以一方而统治之，则大要论所谓谨守病极，各司其。属，有者求之，无者求之，盛者责之，虚者责之之说，将何词以解也?
治饮大法
The sages of antiquity observed the Hetu (River Chart) to elucidate the principles of Yin and Yang and the laws of the Five Phases. The reason why Heaven and Earth can undergo transformation and operate the forces of ghosts and spirits lies essentially in this. The human body is a microcosm of Heaven and Earth; therefore, the processes of its generation and completion cannot exist outside this framework. Thus, "Heaven generates Water, Earth completes it with Six"; in the human body, this corresponds to the Kidney. "Earth generates Fire, Heaven completes it with Seven"; in the human body, this corresponds to the Heart. "Heaven generates Wood, Earth completes it with Eight"; in the human body, this corresponds to the Liver. "Earth generates Metal, Heaven completes it with Nine"; in the human body, this corresponds to the Lung. "Heaven generates Earth, Earth completes it with Ten"; in the human body, this corresponds to the Spleen. Therefore, humans possess Yin and Yang and the Five Phases, identical to Heaven and Earth, and also identical to the Hetu. However, the Yin-Yang and Five Phases of Heaven and Earth follow the natural course of their coming and going, opening and closing. In contrast, the Yin-Yang and Five Phases in the human body may be affected by the external Six Qi (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) or injured by internal Seven Emotions (Joy, Anger, Worry, Thought, Grief, Fear, Fright). This leads to the damage of the Five Phases and the emergence of numerous, complex diseases, which are countless. Generally speaking, there are two main origins: one is among the children of the rich and noble who live in seclusion and do not labor; their diseases arise from overindulgence in food, warmth, and lust, so they have few external contractions but many internal injuries. When the interior becomes deficient, external pathogens easily invade, similar to how a deficiency in the Generating Numbers of the Hetu causes the Completing Numbers to diminish as well. The other is among the poor and lowly who brave wind and rain and toil with their hands and feet; their diseases arise from hunger, cold, and hardship, so they have few internal injuries but many external contractions. When external contractions deepen, internal injuries follow, similar to how if the Completing Numbers of the Hetu are not established, the Generating Numbers cannot survive alone. Although diseases manifest diversely, these two categories form the general principle of their interrelated exterior and interior. It is up to the physician to examine the disease according to the individual, observe the sequence of interior and exterior, and apply appropriate treatment, thereby harmonizing the Yin and Yang and arranging the Five Phases smoothly within the body, just as in the natural order of Heaven, Earth, and the Hetu.
On the Spleen Yang Corresponding to the Central Five
All things rely on Earth for their existence, and the Five Phases cannot be complete without Earth. Thus, Earth is the root of the post-heaven period and the pivot of Metal, Wood, Water, and Fire. In the Luoshu (River Map), the central five is called the "Imperial Standard" (Huangji). It represents the supreme harmony of Heaven and Earth, the basis for the growth and storage of all things. In the human body, it corresponds to the Spleen. Internally, it nourishes the Zang-Fu organs; externally, it nourishes the limbs and bones. Qi and Blood are generated from it. Water is restrained by it and does not flood; Fire is controlled by it and does not flare upward; Wood is supported by it and flourishes; Metal is grounded by it and solidifies. Moreover, when food and drink enter the Stomach, it is the Spleen's healthy transportation that allows the clear essence to ascend and the turbid waste to descend. If the Spleen Earth is injured, the pivot of the whole body becomes unresponsive, and all parts suffer. The Classic says: "With Stomach Qi, there is life; without Stomach Qi, there is death." This means Earth is the foundation of post-heaven nourishment, corresponding to the Central Five in the Luoshu. The Central Five is Yang. When diseased, it fails to transport, leading to symptoms above such as fullness, abdominal distension, and anorexia. When it fails to transform, it leads to symptoms below such as diarrhea, dysentery, and undigested food in stool. These are all failures of the Earth element. Therefore, Zhang Zhongjing formulated Jianzhong Tang (Middle-Building Decoction) and Lizhong Tang (Regulate the Middle Decoction). Other formulas like Sijunzi Tang (Four Gentlemen Decoction) and Liujunzi Tang (Six Gentlemen Decoction) are intended to tonify the Central Five and establish the Imperial Standard. Some ask: Since Spleen Earth belongs to Yin, why is it called the Central Five? The answer is: The Spleen Earth has a Yin substance but a Yang function. Although its substance is Yin, its mechanism of healthy transportation is Yang. Is this not the Central Five of the Luoshu?
On Dragon and Thunder Ministerial Fire
The book *Yi Guan* mentions Dragon Fire and Thunder Fire, metaphorically describing deficient fire flaming upward in the human body. Such fire burns more fiercely when met with water. If one does not understand its nature and attempts to extinguish it with water, the flames will only blaze across the sky until the object is consumed. If one understands its nature and drives it out with fire, the scorching heat will naturally subside. Later physicians such as Zhang Jingyue and Feng Shi endorsed this view, unaware that while the reasoning was correct, the metaphor was inappropriate. Dragon and Thunder fires are the steaming and oppressive fires of Heaven and Earth, a phenomenon where Yin follows Yang. Yin follows Yang, but Yang is suppressed by Yin. Oppression leads to conflict between Yin and Yang, friction creates sound, and lightning results. This is the origin of Dragon and Thunder fire. However, during the hot summer, Yang prevails and Yin is defeated. When Yang prevails and Yin is defeated, the Qi expands and dissipates. Thus, sudden clouds and heavy rain occur; thunder rouses and wind scatters, and the steaming fire is suddenly resolved. This is analogous to the human body being blocked by external Wind pathogens, causing stagnation of pathogenic heat, headache, and aversion to cold. Mild cases require Mahuang Tang (Ephedra Decoction) or Guizhi Tang (Cinnamon Twig Decoction); severe cases require Qinglong Tang (Azure Dragon Decoction) or Baihu Tang (White Tiger Decoction) to induce sweating externally and clear heat internally, allowing the pathogen to retreat. Therefore, Dragon and Thunder fire can metaphorize excess fire in the body, but clearly cannot metaphorize deficient fire. Deficient fire flaming upward in the human body is due to insufficiency of True Yin. True Yin is the single Yin line in the Li trigram. Li Fire has a Yang substance but a Yin root; thus, although Li Yang ascends, Li Yin must descend. If True Yin is deficient, it cannot descend and interact with Kan. Consequently, the Yin in Kan is also deficient. Kan is rooted in Yang. If Kan Yin is deficient, the Yang within Kan has no attachment and flies away. Only hot medicines taken cold, such as Shenfu San (Ginseng and Aconite Powder) or Bawei Wan (Eight-Ingredient Pill), can guide it back. This is like the climate in the ninth month, where Yin strips Yang, and Yang escapes outward, approaching the pure Yin Kun hexagram. One must urgently seek the return of one Yang line to achieve the prosperity of two and three Yang lines, restoring the initial state. Thus, the yang-restoring effect of Shenfu and Bawei is the meaning of "return" in the I Ching, not a verification of Dragon fire burning with water and extinguishing with fire.
On Heavenly Root and Lunar Cave
Shao Yong's poem states: "Coming and going between the Heavenly Root and Lunar Cave, thirty-six palaces are all spring." This truly reflects the continuous interaction and circulation of True Yin and True Yang in the human body. The Heavenly Root is the single Yang line in the Kan trigram, corresponding to the first nine of the Fu hexagram. With this one Yang, the Wood of three, Fire of seven, and Metal of nine all begin here. Hence, it is called Heavenly Root rather than Heaven, to show the source of Yang. The Lunar Cave is the single Yin line in the Li trigram, corresponding to the first six of the Gou hexagram. With this one Yin, the Metal of four, Water of six, and Wood of eight all originate here. Hence, it is called Lunar Cave rather than Moon, to show the beginning of Yin. These two correspond to the Sun and Moon in Heaven and Earth; the Sun goes and the Moon comes, incessantly interacting, allowing Heaven and Earth to form. In the human body, they correspond to the Heart and Kidney. At midnight (Zi hour), Kidney Yang connects upward to the Heart; at noon (Wu hour), Heart Yin descends to interact with the Kidney. The endless coming and going of breath is the source of human life. However, this coming and going, whether of Sun and Moon or Heart and Kidney, operates through "non-action" (Wuwei) for Heaven and Earth, and through "actionless action" for the perfected person. Shao Yong used the character "jian" (interval/gap) to indicate naturalness without force. Although the coming and going seem uninterrupted, it is actually effortless. Ignorant people fail to understand this, acting with妄动 (reckless movement), gradually consuming True Yin. Kidney True Yang is depleted due to licentiousness, leading to a failure of Water and Fire to interact, transforming Tai (Peace) into Pi (Stagnation). The root cause is always the failure of Water and Fire to interact. Zhu Danxi and Li Donggan adhered to the theory that "Yang is often in excess, Yin is often deficient," treating specifically by nourishing Yin and suppressing fire. Their view was biased toward Yin, failing to recognize the unity of Yin and Yang. It was not until Zhao Xianke that the Mingmen (Gate of Life) was identified as the True Yang in Kan. Zhang Jingyue and Feng Shi strongly supported this, emphasizing True Yang. However, they still failed to recognize that True Yin resides in Li, becoming biased toward Yang. Their drawbacks were similar to those of Zhu Danxi and Li Donggan, all stemming from a lack of understanding of the Heavenly Root and Lunar Cave. Here, interpreting Shao Yong's poem clarifies the mutual rooting of Yin and Yang in the body. Their incessant interaction aligns with the Way of Heaven and Earth and should not be weighted arbitrarily by personal opinion.
General Principles of Fluid Retention
Fluid retention (Yin) is Water Qi. Having fluid retention in the body is like having water in the earth. Without water, the earth cannot irrigate all things; without fluids, the body cannot nourish its parts. However, water flowing in the earth becomes springs or tides, nurturing all things; if obstructed, it stagnates and pollutes; if bursting forth, it floods, becoming harmful to all things. Similarly, fluids operating in the body become Jin and Ye (thin and thick fluids), nourishing the body; if stagnant, they cause distension; if reversing, they cause vomiting, becoming diseases of the body. The flow of water is driven by the Yang within Earth; Yang deficiency leads to flooding, Yang stagnation leads to pollution. The operation of fluids is driven by the Yang within the Spleen; Yang deficiency leads to distension, Yang stagnation leads to vomiting. The Classic states: "What Taiyin brings about is accumulated fluid retention and obstruction with fullness." It also states: "Abdominal fullness and enlargement, appearing damp and sluggish." Indeed, Taiyin dominance involves excessive Wet Earth. Excessive dampness leads to Yin deficiency, preventing the Stomach from distributing its fluids and preventing the scattering of essence to the Lungs. Fluids combine with dampness, flowing horizontally along the meridians, forming disease. Dampness tends downward. Although retention varies among the five Zang organs, it always originates in the Spleen. Flowing down the Spleen meridian to the Small Intestine, Bing Fire clashes internally, producing gurgling sounds, called Tan Yin (Phlegm-Fluid). This is like water accumulating in ditches, fermenting and becoming turbid. Flowing sideways to Shaoyang, blocking the left-turning path, causing coughing pain, called Xuan Yin (Hanging Fluid). This is like water damming highlands to form a hanging river. Flowing outward to the limbs, stagnating in skin and muscle, preventing sweating despite the need to sweat, causing body pain, called Yi Yin (Overflowing Fluid). This is like water leaving its channel, spreading everywhere as floodwater. Flowing upward to the chest, blocking Zong Qi (Pectoral Qi), causing shortness of breath and inability to lie flat, resembling edema, called Zhi Yin (Supporting Fluid). This is like water diverting from the sea to form a branch river. In summary, Fluid is Yin in substance but uses Yang. Yang deficiency causes loss of function and worsens fluid retention. Severe fluid retention damages function and further traps Yang. If Water is in the Heart, Heart Yang is trapped, unable to transmit to the Small Intestine, causing palpitations and shortness of breath. If Water is in the Lungs, Lung Yang is trapped, unable to transmit to the Large Intestine, causing spitting of saliva. If Water is in the Spleen, Spleen Yang is trapped, unable to transmit to the Stomach, causing fatigue and heaviness. If Water is in the Liver, Liver Yang is trapped, unable to transmit to the Gallbladder, causing hypochondriac fullness and sneezing pain. If Water is in the Kidneys, Kidney Yang is trapped, unable to transmit to the Bladder, causing epigastric palpitations. Deficiency of any Zang Yang is sufficient to cause harm. The one who controls water in all meridians is primarily the Central State (Spleen/Stomach). When Yang is abundant, Earth controls Water; when Yang is deficient, Water insults Earth. If disaster is not prevented early, and stabilizing methods not sought, initially the exterior Yang is injured, then the interior Yang; initially the Zang Yang, then the Chest Yang. How long before horizontal flooding and the sinking of the land?
Differentiation of Phlegm and Fluid
Although Phlegm (Tan) and Fluid (Yin) share the same source, their manifestations differ. Phlegm is transformed by Fire, becoming turbid due to Heat; Fluid is accumulated Water, becoming clear due to Cold. Careful study of the *Neijing* reveals only Ji Yin, Yi Yin, and Xuan Yin. Discussions of Yin syndromes never mention Phlegm. Only the *Jingui Yaolue* mentions Tan Yin, listing it alongside Yi Yin, Xuan Yin, Zhi Yin, Liu Yin, and Fu Yin. It merely derives phlegm-like symptoms from fluid syndromes, never claiming all fluid syndromes belong to Phlegm. Later generations confused Fluid with Phlegm, merging them into one syndrome. For millennia, this error has persisted, leading to the misdiagnosis of all fluid syndromes as Phlegm, resulting in zero efficacy. Even the wise Zhu Danxi proposed that "all diseases involve Phlegm." Such major principles must be analyzed meticulously. Phlegm and Fluid have distinct Yin-Yang and Water-Fire differences and must not be confused. Etymologically, Tan (Phlegm) contains Fire/Flame radicals, indicating a Fire disease, belonging to Yang. Even in consumptive diseases with coughing and expectoration, which appear cold-deficient, the root is Yin deficiency with blazing Fire and rising Ministerial Fire. Others obviously related to Fire are known and need not be repeated. All water can be called Yin; wine is also called Yin. Yin refers to the moist and soft nature of substances. A disease is called Yin only when Spleen Yang is defeated, Earth is weak and fails to generate Metal, clearing and descending functions fail, and water essence cannot distribute, remaining in meridians and spreading to limbs. This differs from the sticky and coagulated nature of Phlegm. Even Water Qi in Shanghan is a type of Yin. With such distinction, the difference is clear, and treatments are vastly different.
Discussion on Retained and Hidden Fluid
The meanings of Retained (Liu) and Hidden (Fu) are detailed in the *Jingui*. Mr. Jiayan stated: Retained fluid stays and does not leave; if retained fluid leaves but is not completely cleared, it is called Hidden Fluid. Hidden means潜伏 (latent) and not emerging. Ultimately, there is no distinction between the two terms. I argue: Retained Fluid belongs entirely to Water, occupying spaces where Zang Yang is deficient. Hidden Fluid involves chronic internal accumulation of Phlegm-Qi, secretly damaging Chest Yang beforehand. External Water-Fluid enters, carrying Phlegm, and hides in places unreachable by Grand Qi, flowing into vital areas of the Central State. It deepens along meridians, blocking the ascent of Yang. It is ten times more severe than Retained Fluid. Reviewing the *Jingui*: there are five descriptions of Retained Fluid and one of Hidden Fluid. First: Retained Fluid in the Heart area causes back aversion to cold, cold as large as a palm. The Heart area is above the stomach. The back is the mansion of the chest. Water retention in the Heart area depresses both Stomach Yang and Du Meridian Yang. The Back-Shu points of the Stomach are 1.5 cun apart, vertically spaced one cun, exactly the size of a palm. Hence, only this area feels cold. This is Retained Fluid in the Heart manifesting on the back. Second: Retained Fluid causes pain in the Heart area radiating to the Clavicular Fossa (Quepen), worsening with cough. Water retention in the hypochondrium affects Jueyin and Shaoyang. The Shaoyang meridian passes from Quepen to the costal margin and lung collaterals. Water obstruction blocks Sheng Qi, causing pain radiating to Quepen and worsening with cough. This is Retained Fluid in the hypochondrium manifesting in meridians. Third: Retained Fluid in the chest causes shortness of breath, thirst, and joint pain in the limbs. The chest is the site of pivot opening. Water retention blocks opening mechanisms, trapping Yang above (causing shortness of breath/thirst) and Yin-Cold below (preventing limb distribution, causing joint pain). This is Retained Fluid in the chest manifesting in upper/lower/sides. Fourth: Deep pulse indicates Retained Fluid. Internal depression of Water-Fluid loses the mild and expansive quality of Yang. This is Retained Fluid in meridians manifesting in the pulse. Fifth: A patient with a hidden pulse desires spontaneous diarrhea. Diarrhea brings relief, but epigastric hardness/fullness persists. This indicates Retained Fluid attempting to exit. The hidden pulse shows water filling the orifices, preventing Stomach Qi transport. Spontaneous diarrhea offers a path, yet fullness returns. This is Retained Fluid at the stomach gate showing erratic departure. As for Hidden Fluid: Disease above the diaphragm with phlegm-fullness, wheezing, coughing. Attacks bring chills, fever, back/waist pain, tearing/nasal discharge, and tremors. This is Hidden Fluid above the diaphragm. The chest is governed by Yang. Water-Evil hides with Fluid, blocking Yin-Yang ascent/descent. Attacks cause Yin-Yang conflict (chills/fever), Yang invading Yin below (back/waist pain), Yin invading Yin above (tearing/discharge). This resembles Shanghan tremors. This is Hidden Fluid above the diaphragm manifesting intermittently. The five Retained Fluid types in *Jingui* have different symptoms but one source: either Du Meridian Yang fails to extend, or Defensive Yang fails to extend. Total blockage of Yang in one meridian causes retention. Hidden Fluid is worse, blocking all Hand and Foot Yang meridians. Retained Fluid is Water and active; Hidden Fluid includes Phlegm and can be static. Retained Fluid has expelling methods; Hidden Fluid requires warming/mild methods. Though no formulas are listed, severity and urgency can be inferred.
Fluid Syndromes Belong to Yang Deficiency
According to several fluid syndrome entries, both *Neijing* and *Jingui* attribute them to Taiyin. Thus, I say they are caused by Spleen Yang deficiency and water stagnation. Jiayan said: Fluid arises from Dampness, involving Heat or Cold. While plausible, it is vague and requires clarification. Rivers and streams flow underground, held by the Great Qi. Body water enters meridians, penetrates bones, and moistens skin, regulated by Spleen Qi. If Central Yang fails, water either floods or stagnates. Even if Damp-Heat steams and becomes turbid, seemingly harming Yuan Yang, it cannot be simply labeled Cold. Is it not Extreme Yang Deficiency causing Floating Yang to escape? Like ditch water: frozen by cold (Yang blocked externally) or fouled by sun (Yang floating externally). Both are Yang Deficiency. Thus, fluid syndromes belong to Cold, understood?
Discussion on Phlegm-Fluid, Hanging Fluid, Overflowing Fluid, and Supporting Fluid
Fluid pathology is primarily attributed to the Spleen in the *Neijing*, as the Spleen is the most Yin organ lacking Yang function, and is interior-exterior paired with the Stomach. The Stomach is the Sea of Water and Grain. Food entering the Stomach relies on Spleen Yang for transformation. One unit of Spleen Yang dissolves one unit of food; ten units dissolve ten units. Excess food makes Stomach Yin exceed Spleen Yang. Initially, external fluid is not digested; subsequently, internal fluid increases. This injures not only Spleen Yang but also Heart, Lung, Liver, and Kidney Yang. The *Jingui* standardizes four categories and treats via five meridians, all from one source. First, Phlegm-Fluid: Shows fire-flaring signs. The patient was fat, now thin, muscles dissolved into Phlegm. Heart Qi is blocked, pressing Water-Fluid downward with gurgling sounds, leading to palpitations and shortness of breath. Second, Hanging Fluid: Shows hanging signs. After drinking, water flows to the hypochondrium, attaching to the募原 (Muyuan/Diaphragm). Liver Qi knots internally; coughing pulls the hypochondrium in pain, causing hypochondriac fullness. Third, Overflowing Fluid: Shows spreading signs. Drinking water flows to the extremities. Lung Qi is not diffused, stagnating in skin/muscle without sweating, leading to spitting of saliva. Fourth, Supporting Fluid: Shows branching signs. Resembling edema, the Central State loses healthy transportation, Spleen Qi knots internally, causing orthopnea, shortness of breath, and heaviness. Water in the Kidney causing epigastric palpitation is a subtype of Phlegm-Fluid. In Shanghan, Water in the Heart causes fullness and palpitation. Symptoms vary slightly, but treatment is the same, because Kidney Water easily insults the Heart. Thus, Zhang Zhongjing categorized the five Zang within the four fluids, not creating a separate "Five Fluids" outside the four. Later scholars misunderstood *Jingui*, inventing "Five Fluids and Six Syndromes." Haizang, under Wuyin Tang, listed: 1. Retained in Heart area, 2. Supporting in Hypochondrium, 3. Phlegm in Stomach, 4. Overflowing above Diaphragm, 5. Hanging in Intestines. Regardless of symptom errors, the locations contradict classic principles. How could one formula rule them all, contrary to the *Da Yao* saying: "Strictly observe the disease mechanism, assign each to its category. Seek what exists, seek what doesn't. Blame excess, blame deficiency"? What words would explain this?