问曰∶水火合化为湿之说，唐宋后无此论，今虽明明
指示，然犹未有物以验之，恐终不足信世也。
答曰∶此不难辨，譬有咸鱼一条，天气晴久，
变而作雨，则咸鱼必先发湿，咸鱼中之盐即水也。其发湿者，天热逼之，则水来交于火，以
济其亢旱也。又如有干茶叶，一经火烘，即行回润，是茶叶中原具润汁。但火不烘则不发润，
一遇火烘即发润，此又是火交于水，即化为湿之一验。
问曰∶六气有火热，又有燥气，时医于三者往往混同无别。今请问燥之分别，与
治燥之
药？
答曰∶三者各别，未可并论，今子所问燥与火热回殊。盖燥与湿对，湿为水火相
交而化
者也，燥者水火不交之气也。火不蒸水则云雨不生，水不济火则露泽不降，而燥于是乎成矣。
水不润，则木气不滋而草木黄落；火不蒸，则土气不发，而膏脉枯竭。究水火之所以不交，
由于金性之收，收止水火，各返本宅，故神曰蓐收。令司秋月，草木枯稿，土泉涸竭，是
为燥金用事之验也。人秉燥金之气者，为阳明经属胃与大肠。胃虽属土而以燥为主，故与大
肠统成燥金，金收而水火不交，是为燥，则燥者，水火消耗之气也。肠胃所以化饮食，皆以
其燥能消耗之也。燥化不足则不消水，为呕吐、泄利，用半夏、陈皮、白术为主。吴萸亦辛
燥，熟于九月正得燥金之气，故去水饮以燥胜湿也。苍术正燥胃土；KT 仁辛涩正入大肠；
草果燥烈，消瓜果之湿积。然比皆燥气不足之湿病也，若燥之正病，则皆属燥气有余。盖有
津液则不燥，无津液则燥，仲景以存津液为主，正以治燥，其有火不蒸水而津液不升。如五
苓散之有口渴证，宜用桂枝，理中汤之有口渴证，宜用干姜，肾气丸之治下消证，宜用桂附。
大便寒结者，用当归之温润，用巴豆之辛润，皆是治火不蒸水之燥。西医用蓖麻油通大肠，
亦是温润之法，皆治寒燥者也。此证最少，惟火燥之证最多。水不濡火，则成火燥，血液
不流于下，则肠中干枯、膈食不下、粪如羊屎。宜黑豆、脂麻、肉苁蓉、当归、麻仁、生地
、山药生液以润之。水津不腾于上，口干、肺萎、痰郁、咳逆，宜阿胶、贝母、麦冬、紫菀、
瓜霜、百合、白蜜、燕
以其体甚高，又属气分，阳津易达而阴液难到也，麦冬、天冬、当归、人参以治
之。燥甚口渴，花粉、粉葛、盐梅皆润生津。火太甚有燥屎，急下之，用芒硝以润涤，用大
黄以攻利，此其攻下正是救津液，有津液则不燥矣。世人但知下火，而不知是存津液正是救
燥，然下之又能亡津液，故又有戒下者。他如噤口痢，津液不升，故不纳谷，西医言是肠胃
发炎，久则腐烂。按此正是水不濡火之极致，宜以黄连、生地为主，以白菊、花粉、黄芩为
佐。又阴吹有燥屎，猪膏发煎，亦是润肠之义，风能胜湿，风伤血则筋燥，玉竹、当归为主。
小便燥涩，前仁、滑石、冬葵子、苁蓉以滑利之。妇人子脏干燥，
可借用地黄汤。心中乏液则烦，轻则柏子仁、枣仁以润之，重则鸡子黄、阿胶以润之。《内
经》云肾恶燥，肾精不足宜枸杞、菟丝、熟地、龟胶、阿胶，又小便自利大便反硬者，仲景
用附子、白术，又是以火蒸水，通致津液之法。总之燥是水火不交之耗气也，故有寒燥、有
热燥，而热燥尤多，则以其火就燥故也。
问曰∶火热二者，几不可别，而《内经》以火属少阳，以热属少阴，治火治热用
药当如
何分别？
答曰∶此不可辨，有如夏月天气亢阳，烈日当空，挥汗淋漓，此为热，乃天之阳
也。
有如燔柴炙炭，势若燎原，此为火，乃地之阳也。少阴心肾，系人之坎离，虽心属于火，亦
如天之有日，积阳而成，非若丽本则明之火，故少阴不名为火，而名热气者，从其本于天之
阳名之也。此气虽属于心，实根于肾，乃肾命门坎水中之一阳，交于心而成此热气，故中心
烦热。仲景用黄连阿胶鸡子黄汤，阿胶得阿井伏流之水，性能伏水中之阳；黄连大寒得水之
性，故去热；鸡子黄滋补心液。三味乃填离清坎之药，故治心内之热。栀子苦寒，有皮膈象
心包。内之子赤，正属心之色。其花白色，当属肺金。结子成赤，当属心火。是为从肺入心，
正治心中烦热之药。《内经》言心为君主，而肺为相傅之官，以制节心君之太过。栀子花白
子赤，正是以肺金而归制心火者也。故仲景治心中懊 ，必用栀子淡豆豉汤。豆为肾之谷，
蒸发为豉，能升肾中水阴，以降心中之热，观此则知少阴心肾均属热气，不作火论也。连翘
有壳有子，亦似包与心中，气味轻清，为清热入心之品。莲心得坎水之气，上生于莲子心中，
有似人之心中，故入心中清热。竹叶、寒水石、石膏均禀天水之寒气，故治一切热。地骨皮
凌冬不凋，得水之阴，故治热。元参色黑，入肾治热。热与火不同，有如大黄，是治火之药，
禀地气，入后天之血分者也。芒硝是治热之药，禀天水之气，入先天气分者也。紫雪丹不用
大黄，而用石膏、芒硝、犀角、羚羊、寒水石、金箔，皆本天水之阴以清热也。牛黄清心丸
有大黄入血分，有牛黄走膈膜，是入包络，则本地火之阴以泻火也。盖天之阳在空中，为热
气附于木，则燃为火。人之阳在心中，亦为热附于血分，则归包络，合肝木而为火。
知此则知热与火有别，心肾阴虚则生热，天王补心丹用二冬、二地、丹麦、元参，皆是益水
阴，其济心中之热。骨蒸盗汗痨蒸是水气外泄，阳越而热，非火也，宜清润收降，地骨皮、
丹皮、知母、黄柏、冬桑叶、归胶、地黄、麦冬、元参皆益天水之阴，以清热也。知母叶至
难死，拔之犹生，即此知其得水气多，故清气分之热。夫气属阳，血属阴，瘀血阻气则阳不
入阴，亦蒸热汗出，宜破其血，使气得入于血中则不壅热。桃仁、丹皮、为主。仲景 虫丸、
温经汤，皆主破血以通气，气通则热不蒸，此为治热之变法。诸疮尖起作脓，每每发热，乃
是气来蒸血，气盛则血随气化，而成脓。如不发热，则气不盛，难于蒸脓，宜黄 桂附以补
气，助其发热而血乃化，痘证亦然，观此则知热属气分，与火之属血分者不同，故藕汁、梨
汁、莱菔汁、西瓜、珍珠、水晶石、元精石、寒水石皆得水气以清热。
问曰∶血属火，气属
水。今云热属气分，何以心主热气，而又能生血也哉？
答曰∶心在人身，如天之有日，天阳
生地火，故阳隧取日而生火，则附于木。心经化液而生血，则归于肝，所以肝与包络胆均引
相火，而少阴心与肾独主热气也。有相火助热之证，清用芩连，攻用硝黄，是治热兼治火也，
有如夏既亢热，又添炉火之状。又有热助相火之证，如日晒火山，风扬炬焰之状，论证者当
类推焉，夫以五脏论，则心属火，以六气论，则心肾均主阳热，而火当属之少阳，可分可合，
总宜细辨。
问曰∶天阳生地火，故心生包络之相火，包络之血下藏于肝，故肝寄相火，是木
火一家
之义也。乃包络与肝，名厥阴经，统称风气，不称相火，而少阳胆与三焦独言火，君火、相
火后世之说，与六气不合一气，治之何也？
答曰∶包络称相火，乃后世之说，非《内经》本
义。《内经》只言膻中者，臣使之官，喜乐出焉。谓相心布化，血脉畅则喜乐。凡人血足则
不怯寒，可知血属热，气不专属火，故肝与包络不称相火。惟包络与三焦通，故三焦之火能
合于包络，肝与胆相连，故曰肝能化火。究竟火气全归于胆，乃是从木生出之火，胆系连肝
膈，通膜网，即三焦也。胆火之化全在三焦，连网中往来，故胆与三焦同司相火。火逆呕苦，
黄芩为正药，苦而绿色，故入胆也。柴胡得木气透达，使火不郁。荷叶亦能清散胆火，象震
而味苦故也。青黛色青味苦，清三焦肝胆之火，质轻清，故治喉证。《内经》示二阴一阳结
为喉痹，二阴是少阴，主热，一阳是少阳，主火热与火结，则为喉痹。故治喉症，总宜祛火
而兼清热也。蓝叶治肝胆之火，较青黛之性略沉。海金沙子结叶间，如胆附肝之象，而味苦
能清火，故为治砂淋等之要药。三焦与胆通，惟胆中相火结，三焦之水乃结，此药以结解结，
故治之。五倍子亦子在叶间，而味带咸故润降，润祛肺之痰火。实亦清胆，以其子在叶间
也。又清三焦，以三焦根于肾系，五倍子咸又能入肾故也。桑寄生附木而生，象胆附肝，味
酸苦得木火之味，能清胆火，治风热筋脉结等症。胆通三焦之网膜，外连于筋，寄生如藤附
木，象人之筋也。龙胆草苦而根多，故主降胆与三焦之火，胡黄连中空，与黄芩均能走膜中
空窍，而味极苦，正治相火，故主痨蒸。此与黄连之苦不同，黄连得苦之正味，故入心泻热
。胆草、胡黄连得苦兼酸之变味，故入肝胆及三焦。夏枯草正秉春少阳之气而生，至夏则枯
，味亦苦，正清肝胆及三焦之火。瘰 者，顶上筋脉之结也，此草蔓生，象人筋脉，质轻浮
走上焦，故治颈上之结，又取自枯，有消耗之义。青蒿色青味苦，正枯肝胆之相火，其节中
必生红虫，乃感风化而生之虫也，故青蒿为去风清热之药。人之痨虫，皆肝气相火相煽而生
，假血以成质，故必骨蒸乃生痨虫。青蒿节以虫杀虫，消瘀去蒸，借虫以攻血，借风气以散
郁火也。防己味似龙胆而中空，能通膜网故能清三焦相火，以利其水。栝蒌实子有油，而气
烈，包有瓤而味苦，捣烂合用能解膈膜之痰火。山豆根色白味苦，入肺泻火，盖以金平木则
火不上，而克金矣，故治喉痛。喉是少阴心与三焦之证，豆根治木火，是治三焦也。马齿苋
叶内有水银，得金水之性也，味酸气寒，故能清三焦之火以利水。鲤鱼胆、青鱼胆以类入肝
胆，味苦，又生水中，正得水性，为治肝胆火之正药。故岩喉目，熊生于山，而毛兽秉风性，
胆又极苦，故入肝胆清火而治喉目。地骨皮极浓象人膜，味苦气寒，故清三焦之火，三焦与
胆同司相火，然三焦之根在肾，肾中阳气上通，亦以三焦为路道，故肾能移热于三焦。地骨
皮入土极深，得土下泉水之气，故能清肾水中之热，能泻命门中热也。
问：水火相合化为湿气的说法，唐宋以后就没有这种论述了。现在虽然明确指出了这一点，但还没有实物来验证它，恐怕终究不足以让世人信服。
答：这不难辨别。譬如有咸鱼一条，天气晴朗久了，突然变天要下雨，那么咸鱼一定会先变得潮湿。咸鱼中的盐就是水。咸鱼变潮，是因为天热逼迫它，使得水与火相交，以济助其亢盛的旱情。又如干茶叶，一经火烘烤，就会回润，这说明茶叶中原具有滋润的汁液。只是没有火烘就不显湿润，一遇火烘就显湿润，这又是火与水相交，即化为湿气的又一验证。
问：六气中有火热，又有燥气，当时的医生对这三者往往混淆不分。现在请问燥气的区别，以及治疗燥气的药物？
答：三者各不相同，不可混为一谈。你刚才问的燥与火热截然不同。燥与湿相对，湿是水火相交而化生的，燥则是水火不相交的气。火不蒸腾水，则云雨不生；水不济助火，则露泽不降，燥气因此形成。水不能滋润，则木气不滋长，草木枯黄凋落；火不蒸腾，则土气不发动，膏脉枯竭。究其水火不相交的原因，是由于金性的收敛作用。收敛使水火各返本位，所以神称为蓐收，掌管秋月。此时草木枯稿，土壤泉水干涸，这就是燥金当令的验证。人禀受燥金之气，属于阳明经，关联胃与大肠。胃虽属土但以燥为主，所以与大肠统称为燥金。金性收敛导致水火不相交，这就形成了燥，所以燥是水火消耗的气。肠胃消化饮食，都是依靠其燥性能消耗食物。如果燥化不足就不能消化水液，出现呕吐、泄泻，治疗以半夏、陈皮、白术为主。吴茱萸也辛燥，在九月成熟正得燥金之气，所以能去除水饮，以燥胜湿。苍术正能燥胃土；郁李仁辛涩，正入大肠；草果燥烈，能消除瓜果类的湿积。但这些都属于燥气不足的湿病。如果是燥的正病，则都属于燥气有余。因为有津液就不燥，无津液才燥。张仲景以保存津液为主，正是治疗燥的方法。如果有火不蒸腾水导致津液不升的情况，如五苓散证中出现口渴，宜用桂枝；理中汤证中出现口渴，宜用干姜；肾气丸治疗下消证，宜用桂枝、附子。大便寒结的，用当归的温润，用巴豆的辛润，这些都是治疗火不蒸水之燥的方法。西医使用蓖麻油通大肠，也是温润之法，都治疗寒燥。这种证候最少，只有火燥的证候最多。水不能濡养火，则形成火燥，血液不流于下部，导致肠中干枯、膈食不下、粪便像羊屎一样。宜用黑豆、脂麻、肉苁蓉、当归、麻仁、生地、山药等生津液以滋润。如果水津不能腾涌于上，出现口干、肺萎、痰郁、咳逆，宜用阿胶、贝母、麦冬、紫菀、瓜霜、百合、白蜜、燕窝（因其体甚高，又属气分，阳津易达而阴液难到），以及麦冬、天冬、当归、人参来治疗。燥甚口渴，可用花粉、粉葛、盐梅等润生津液。火太盛有燥屎，需急下，用芒硝以润涤，用大黄以攻利，这里的攻下正是为了救津液，有津液就不燥了。世人只知道泻火，而不知道保存津液正是救燥，然而泻下又能亡失津液，所以又有禁止泻下的说法。其他如噤口痢，津液不升，所以不能进食，西医说是肠胃发炎，久则腐烂。按此正是水不濡火的极致，宜以黄连、生地为主，以白菊、花粉、黄芩为佐。还有阴吹伴有燥屎，猪膏发煎，也是润肠的意思。风能胜湿，风伤血则筋燥，以玉竹、当归为主。小便燥涩，用车前子、滑石、冬葵子、肉苁蓉等滑利之。妇人子宫干燥，可借用地黄汤。心中乏液则心烦，轻则用柏子仁、枣仁滋润，重则用鸡子黄、阿胶滋润。《内经》说肾恶燥，肾精不足宜用枸杞、菟丝子、熟地、龟胶、阿胶。还有小便自利大便反硬的，张仲景用附子、白术，这是以火蒸水，通达津液的方法。总之，燥是水火不相交的耗损之气，所以有寒燥、有热燥，而热燥尤其多，这是因为火就燥的缘故。
问：火热二者，几乎难以区分，而《内经》以火属少阳，以热属少阴，治疗火和治疗热的用药应当如何分别？
答：这可以辨别。好比夏天天气亢阳，烈日当空，挥汗淋漓，这是热，乃天之阳。好比燃烧柴炭，势若燎原，这是火，乃地之阳。少阴心肾，系人之坎离，虽然心属于火，也像天上有太阳，积阳而成，不像依附本体才明亮的火，所以少阴不名为火，而名热气，是遵循其源于天之阳的名称。这股气虽然属于心，实则根于肾，是肾命门坎水中的一阳，上交于心而成此热气，所以心中烦热。张仲景用黄连阿胶鸡子黄汤，阿胶得阿井伏流之水，性能潜伏水中之阳；黄连大寒得水之性，所以去热；鸡子黄滋补心液。这三味药是填补离卦、清澄坎卦的药物，所以治疗心内之热。栀子苦寒，有皮隔象心包，里面的子赤色，正属心的颜色。其花白色，当属肺金。结子成赤色，当属心火。这是从肺入心，正治心中烦热的药。《内经》说心为君主，而肺为相傅之官，以制节心君的太过。栀子花白子赤，正是以肺金而归制心火者也。所以张仲景治疗心中懊憹，必用栀子淡豆豉汤。豆为肾之谷，蒸发为豉，能升肾中水阴，以降心中之热，看这个就知道少阴心肾均属热气，不作火论。连翘有壳有子，也似包裹心中，气味轻清，为清热入心的药品。莲心得坎水之气，上生于莲子心中，有似人之心中，所以入心中清热。竹叶、寒水石、石膏均禀承天水之寒气，所以治一切热。地骨皮凌冬不凋，得水之阴，所以治热。玄参色黑，入肾治热。热与火不同，有如大黄，是治火的药，禀地气，入后天之血分。芒硝是治热的药，禀天水之气，入先天气分。紫雪丹不用大黄，而用石膏、芒硝、犀角、羚羊角、寒水石、金箔，皆本天水之阴以清热。牛黄清心丸有大黄入血分，有牛黄走膈膜，入包络，是本地火之阴以泻火。大概天之阳在空中，为热气附于木，则燃为火。人之阳在心中，也为热附于血分，则归包络，合肝木而为火。知道这个就知道热与火有别。心肾阴虚则生热，天王补心丹用二冬、二地、丹麦参、玄参，皆是益水阴，以济心中之热。骨蒸盗汗痨蒸是水气外泄，阳越而热，不是火，宜清润收降，地骨皮、丹皮、知母、黄柏、冬桑叶、当归胶、地黄、麦冬、玄参皆益天水之阴，以清热。知母叶至难死，拔之犹生，由此可知其得水气多，所以清气分之热。夫气属阳，血属阴，瘀血阻气则阳不入阴，也蒸热汗出，宜破其血，使气得入于血中则不壅热。以桃仁、丹皮为主。张仲景虻虫丸、温经汤，皆主破血以通气，气通则热不蒸，此为治热的变法。诸疮尖起作脓，每每发热，乃是气来蒸血，气盛则血随气化，而成脓。如不发热，则气不盛，难于蒸脓，宜用黄芪、桂枝、附子以补气，助其发热而血乃化，痘证亦然，看这个就知道热属气分，与火之属血分者不同。所以藕汁、梨汁、莱菔汁、西瓜、珍珠、水晶石、元精石、寒水石皆得水气以清热。
问：血属火，气属水。现在说热属气分，为什么心主热气，而又能生血呢？
答：心在人身，如天之有日，天阳生地火，所以阳隧取日而生火，则附于木。心经化液而生血，则归于肝，所以肝与包络胆均引相火，而少阴心与肾独主热气。有相火助热之证，清用芩连，攻用硝黄，是治热兼治火，有如夏天既亢热，又添炉火之状。又有热助相火之证，如日晒火山，风扬炬焰之状，论证者应当类推。夫以五脏论，则心属火，以六气论，则心肾均主阳热，而火当属之少阳，可分可合，总宜细辨。
问：天阳生地火，故心生包络之相火，包络之血下藏于肝，故肝寄相火，是木火一家之义。乃包络与肝，名厥阴经，统称风气，不称相火，而少阳胆与三焦独言火，君火、相火是后世之说，与六气不合一气，治疗该如何？
答：包络称相火，乃后世之说，非《内经》本义。《内经》只言膻中者，臣使之官，喜乐出焉。谓相心布化，血脉畅则喜乐。凡人血足则不怯寒，可知血属热，气不专属火，故肝与包络不称相火。惟包络与三焦通，故三焦之火能合于包络，肝与胆相连，故曰肝能化火。究竟火气全归于胆，乃是从木生出之火，胆系连肝膈，通膜网，即三焦也。胆火之化全在三焦，连网中往来，故胆与三焦同司相火。火逆呕苦，黄芩为正药，苦而绿色，故入胆也。柴胡得木气透达，使火不郁。荷叶亦能清散胆火，象震卦而味苦故也。青黛色青味苦，清三焦肝胆之火，质轻清，故治喉证。《内经》示二阴一阳结为喉痹，二阴是少阴，主热，一阳是少阳，主火热与火结，则为喉痹。故治喉症，总宜祛火而兼清热。蓝叶治肝胆之火，较青黛之性略沉。海金沙子结叶间，如胆附肝之象，而味苦能清火，故为治砂淋等之要药。三焦与胆通，惟胆中相火结，三焦之水乃结，此药以结解结，故治之。五倍子亦子在叶间，而味带咸故润降，润祛肺之痰火。实亦清胆，以其子在叶间也。又清三焦，以三焦根于肾系，五倍子咸又能入肾故也。桑寄生附木而生，象胆附肝，味酸苦得木火之味，能清胆火，治风热筋脉结等症。胆通三焦之网膜，外连于筋，寄生如藤附木，象人之筋也。龙胆草苦而根多，故主降胆与三焦之火，胡黄连中空，与黄芩均能走膜中空窍，而味极苦，正治相火，故主痨蒸。此与黄连之苦不同，黄连得苦之正味，故入心泻热。胆草、胡黄连得苦兼酸之变味，故入肝胆及三焦。夏枯草正秉春少阳之气而生，至夏则枯，味亦苦，正清肝胆及三焦之火。瘰疬者，顶上筋脉之结也，此草蔓生，象人筋脉，质轻浮走上焦，故治颈上之结，又取自枯，有消耗之义。青蒿色青味苦，正枯肝胆之相火，其节中必生红虫，乃感风化而生之虫也，故青蒿为去风清热之药。人之痨虫，皆肝气相火相煽而生，假血以成质，故必骨蒸乃生痨虫。青蒿节以虫杀虫，消瘀去蒸，借虫以攻血，借风气以散郁火也。防己味似龙胆而中空，能通膜网故能清三焦相火，以利其水。栝蒌实子有油，而气烈，包有瓤而味苦，捣烂合用能解膈膜之痰火。山豆根色白味苦，入肺泻火，盖以金平木则火不上，而克金矣，故治喉痛。喉是少阴心与三焦之证，豆根治木火，是治三焦也。马齿苋叶内有水银，得金水之性也，味酸气寒，故能清三焦之火以利水。鲤鱼胆、青鱼胆以类入肝胆，味苦，又生水中，正得水性，为治肝胆火之正药。故岩喉目，熊生于山，而毛兽秉风性，胆又极苦，故入肝胆清火而治喉目。地骨皮极浓象人膜，味苦气寒，故清三焦之火，三焦与胆同司相火，然三焦之根在肾，肾中阳气上通，亦以三焦为路道，故肾能移热于三焦。地骨皮入土极深，得土下泉水之气，故能清肾水中之热，能泻命门中热也。
Q: The theory that the combination of water and fire transforms into dampness was not discussed after the Tang and Song dynasties. Although it is clearly pointed out now, there is no physical evidence to verify it, so it may ultimately fail to convince the world.
A: This is not difficult to distinguish. For example, take a salted fish. After a long period of sunny weather, if the weather changes and rain is about to fall, the salted fish will become moist first. The salt in the salted fish is essentially water. The fish becomes moist because the heat of the sky forces it, causing water and fire to interact to alleviate its excessive dryness. Similarly, dried tea leaves, when roasted by fire, regain moisture, indicating that they originally contain moistening juices. Without fire roasting, they do not appear moist; upon encountering fire roasting, they become moist. This is another verification of fire interacting with water, i.e., transforming into dampness.
Q: Among the Six Qi (Six Climate Factors), there are Heat-Fire and Dryness. Contemporary physicians often confuse these three. May I ask for the distinction of Dryness and the herbs used to treat it?
A: The three are distinct and should not be conflated. The Dryness you asked about is fundamentally different from Heat-Fire. Dryness is opposite to Dampness; Dampness is transformed from the interaction of water and fire, whereas Dryness is the state where water and fire do not interact. If fire does not evaporate water, clouds and rain will not form; if water does not nourish fire, dew and moisture will not descend, thus forming Dryness. If water fails to moisten, Wood Qi cannot nourish, leading to the yellowing and falling of grass and trees; if fire fails to evaporate, Earth Qi cannot activate, leading to the exhaustion of fatty tissues and vessels. The reason for the non-interaction of water and fire lies in the contracting nature of Metal. Contraction causes water and fire to return to their original homes; hence the deity is called Rushou (Harvest Receiver), governing autumn. At this time, grass and trees wither, and soil springs dry up, which is the verification of Dry-Metal being in charge. Humans who inherit the Qi of Dry-Metal belong to the Yangming Meridian, associated with the Stomach and Large Intestine. Although the Stomach belongs to Earth, it is primarily Dry, so together with the Large Intestine, they constitute Dry-Metal. Metal's contraction prevents the interaction of water and fire, creating Dryness; thus, Dryness is the Qi consumed by the separation of water and fire. The digestion of food and drink in the intestines and stomach relies on this drying/consuming property. If the drying transformation is insufficient, water cannot be processed, leading to vomiting and diarrhea; treatment focuses on Banxia (Pinelliae Rhizoma), Chenpi (Citri Reticulatae Pericarpium), and Baizhu (Atractylodis Macrocephalae Rhizoma). Wuyu (Evodiae Fructus) is also acrid-dry; ripening in the ninth month, it perfectly obtains the Qi of Dry-Metal, thus removing fluid retention by overcoming dampness with dryness. Cangzhu (Atractylodis Rhizoma) dries Spleen-Stomach Earth; Yuren (Prunella Fructus) is acrid-astringent and enters the Large Intestine; Caoguo (Tsaoko Fructus) is intensely drying and eliminates damp accumulation from melons and fruits. However, these all treat damp diseases caused by insufficient dryness. If it is a primary disease of Dryness, it belongs to an excess of Dryness Qi. Presence of body fluids means no dryness; absence of body fluids means dryness. Zhang Zhongjing emphasized preserving body fluids, which is precisely treating dryness. In cases where fire fails to evaporate water, preventing fluid ascent, such as thirst in Wuling San syndrome, Guizhi (Cinnamomi Ramulus) is appropriate; in Lizhong Tang syndrome with thirst, Ganjiang (Zingiberis Rhizoma) is appropriate; in Shenqi Wan for treating lower Xiao (wasting-thirst), Guizhi (Cinnamomi Ramulus) and Fuzi (Aconiti Lateralis Radix Praeparata) are appropriate. For cold constipation, Danggui (Angelicae Sinensis Radix) provides moist-warmth, and Badou (Crotonis Fructus) provides acrid-moisture; both treat dryness caused by fire failing to evaporate water. Western medicine uses Ricinus oil to unblock the large intestine, which is also a moist-warming method, treating cold dryness. Such cases are rare; Fire-Dryness cases are most common. If water fails to moisten fire, Fire-Dryness forms, blood fails to flow downward, leading to dry intestines, dysphagia, and feces like sheep droppings. Treatment involves Heidou (Sojae Semen Nigrum), Zhima (Sesami Semen), Rousongrong (Cynomorphii Herba), Danggui (Angelicae Sinensis Radix), Haren (Cannabis Semen), Shengdi (Rehmanniae Radix), and Shanyao (Dioscoreae Rhizoma) to generate fluids and moisten. If water fluids fail to ascend, causing dry mouth, lung atrophy, phlegm stagnation, and cough/counterflow qi, Ejiao (Asini Corii Colla), Beimu (Fritillariae Bulbus), Maidong (Ophiopogonis Radix), Ziwan (Asternis Radix), Guashuang (Gypsi Fibrum), Baihe (Lilii Bulbus), Baimi (Mellis), and Yanci (Hirundo Nidus—due to its high position and association with Qi level, Yang fluids reach easily but Yin fluids rarely arrive) are used. Maidong (Ophiopogonis Radix), Tiandong (Asparagi Radix), Danggui (Angelicae Sinensis Radix), and Renshen (Ginseng Radix) are also employed. For severe dryness with thirst, Huafen (Trichosanthis Radix), Fenge (Puerariae Radix), and Yanmei (Prunii Mume Fructus) moisten and generate fluids. If fire is excessive with dry stool, urgent purgation is needed; Mangxiao (Natrii Sulfas) moistens and cleanses, while Dahuang (Rhei Radix et Rhizoma) attacks and drains. This purgation saves body fluids; with fluids, there is no dryness. People only know to purge fire, not realizing that saving fluids saves against dryness. However, purging can also deplete fluids, hence warnings against purging. Other examples include Jin Kou Li (Lockjaw Dysentery), where fluids do not ascend, preventing food intake; Western medicine calls this intestinal inflammation, leading to rot over time. This is the extreme of water failing to moisten fire. Treatment prioritizes Huanglian (Coptidis Rhizoma) and Shengdi (Rehmanniae Radix), assisted by Baiju (Chrysanthemi Flos), Huafen (Trichosanthis Radix), and Huangqin (Scutellariae Radix). Yin Chui (flatulence passing through vagina) with dry stool is treated with Pig Fat and Hair Decoction (Zhigao Fa Jian), embodying intestinal moistening. Wind overcomes dampness; wind injuring blood leads to sinew dryness, treated with Yuzhu (Polygonati Odorati Rhizoma) and Danggui (Angelicae Sinensis Radix). Dry and painful urination is treated with Cheqianzi (Plantaginis Semen), Huashi (Talcum), Dongkuizi (Malvae Semen), and Rousongrong (Cynomorphii Herba) to lubricate. Female uterine dryness can be treated with Dihuang Tang (Rehmanniae Decoction). Heart lacking fluids causes vexation; mild cases use Baiziren (Biota Seed) and Zaoren (Ziziphi Spinosae Semen); severe cases use Jizihuang (Elevi Ovis Ovum) and Ejiao (Asini Corii Colla). The *Neijing* states the Kidney dislikes dryness; for Kidney essence deficiency, Gouqi (Lycii Fructus), Tusizi (Cuscutae Semen), Shudi (Rehmanniae Radix Preparata), Guijiao (Testudinis Carapax et Plastrum Colla), and Ejiao (Asini Corii Colla) are used. When urination is frequent but stool is hard, Zhang Zhongjing uses Fuzi (Aconiti Lateralis Radix Praeparata) and Baizhu (Atractylodis Macrocephalae Rhizoma), employing fire to evaporate water and circulate fluids. In summary, Dryness is the consuming Qi of non-interacting water and fire, manifesting as Cold Dryness or Heat Dryness, with Heat Dryness being more common due to "fire adhering to dryness."
Q: Heat and Fire are hardly distinguishable, yet the *Neijing* assigns Fire to Shaoyang and Heat to Shaoyin. How should medications for treating Fire and Heat be distinguished?
A: They can be distinguished. Consider summer weather: intense sun, sweating profusely—this is Heat, the Yang of Heaven. Consider burning wood and charcoal, spreading like a prairie fire—this is Fire, the Yang of Earth. Shaoyin Heart-Kidney relates to Kan and Li in humans. Although the Heart belongs to Fire, it is like the sun in the sky, accumulated Yang, unlike fire that requires fuel to shine. Thus, Shaoyin is named Heat Qi, following its origin from Heavenly Yang. This Qi belongs to the Heart but roots in the Kidney; it is the single Yang within the Kan Water of the Kidney Mingmen, ascending to the Heart to form Heat Qi, causing internal vexation and heat. Zhang Zhongjing uses Huanglian Ejiao Jizi Huang Tang (Coptis, Donkey-Hide Gelatin, and Chicken Yolk Decoction). Ejiao obtains water from the A-Jing underground stream, possessing the ability to submerge Yang within water; Huanglian is extremely cold, sharing the nature of water, thus clearing heat; Jizi Huang nourishes Heart fluids. These three ingredients fill Li (Fire) and clear Kan (Water), treating internal Heart heat. Zhi zi (Gardeniae Fructus) is bitter and cold; its skin and septum resemble the Pericardium. Its inner seeds are red, corresponding to the Heart's color. Its flowers are white, corresponding to Lung Metal. Its fruit turns red, corresponding to Heart Fire. It enters from Lung to Heart, correctly treating internal Heart vexation. The *Neijing* states the Heart is the Sovereign, and the Lung is the Minister, regulating the Sovereign's excess. Zhi zi's white flower and red seed exemplify using Lung Metal to control Heart Fire. Thus, Zhang Zhongjing uses Zhi zi Chi Dou Tang (Gardenia and Fermented Soybean Decoction) for internal restlessness. Soybeans are the grain of the Kidney; fermented into Chi dou (Fermented Soybean), they raise Kidney Yin fluids to descend Heart Heat. This shows Shaoyin Heart-Kidney belongs to Heat Qi, not Fire. Lian qiao (Forsythiae Fructus) has a shell and seeds, resembling a covering for the Heart; its light and clear aroma makes it a heat-clearing herb entering the Heart. Lian xin (Nelumbinis Plumula) obtains Kan Water Qi, growing atop the Lotus seed heart, resembling the human Heart, thus clearing Heart heat. Zhu ye (Bambusae Folium), Hanshui shi (Halloysitum Rubrum), and Shigao (Gypsum Fibrosum) inherit the cold Qi of Heaven/Water, treating all heat. Digupi (Lycii Cortex) remains green in winter, obtaining Water Yin, thus treating heat. Xuanshen (Scrophulariae Radix) is black, enters the Kidney, and treats heat. Heat differs from Fire. Dahuang (Rhei Radix et Rhizoma) treats Fire, inheriting Earth Qi, entering the Postnatal Blood aspect. Mangxiao (Natrii Sulfas) treats Heat, inheriting Heavenly Water Qi, entering the Prenatal Qi aspect. Zixue Dan (Purple Snow Pill) does not use Dahuang but uses Shigao (Gypsum Fibrosum), Mangxiao (Natrii Sulfas), Xijiao (Rhinocerotis Cornu), Lingyangjiao (Saigae Tataricae Cornu), Hanshui shi (Halloysitum Rubrum), and Jinbo (Folium Aurum), all based on Heavenly Water Yin to clear heat. Niuhuang Qingxin Wan (Calculus Bovis Clear Heart Pill) contains Dahuang entering the Blood aspect, and Niuhuang (Calculus Bovis) moving through the diaphragm into the Pericardium, using Local Fire Yin to purge Fire. Generally, Heavenly Yang is in the air; when Heat attaches to Wood, it burns into Fire. Human Yang is in the Heart; when Heat attaches to Blood, it returns to the Pericardium, combining with Liver Wood to form Fire. Knowing this distinguishes Heat from Fire. Heart-Kidney Yin deficiency generates Heat; Tianwang Buxin Dan (Emperor of Heaven's Special Pill to Tonify the Heart) uses Erdong (Ophiopogonis and Asparagus roots), Erdi (Rehmannia roots), Danshen (Salvia miltiorrhiza root), and Xuanshen (Scrophulariae Radix) to benefit Water Yin and balance Heart Heat. Bone-steaming night sweats and consumption steaming result from Water Qi leaking outward, Yang escaping, and generating Heat, not Fire. Treatment requires clearing, moistening, descending, and astringing. Digupi (Lycii Cortex), Danpi (Moutan Cortex), Zhimu (Anemarrhenae Rhizoma), Huangbai (Phellodendri Cortex), Dong Sangye (Mori Folium), Guijiao (Donkey-Hide Gelatin), Dihuang (Rehmanniae Radix), Maidong (Ophiopogonis Radix), and Xuanshen (Scrophulariae Radix) all benefit Heavenly Water Yin to clear Heat. Zhimu leaves are extremely resilient; even if pulled, they grow back, indicating abundant Water Qi, thus clearing Qi-level Heat. Qi belongs to Yang, Blood to Yin. Blood stasis obstructing Qi prevents Yang from entering Yin, causing steaming heat and sweating. Breaking blood allows Qi to enter Blood, relieving heat stagnation. Taoren (Persicae Semen) and Danpi (Moutan Cortex) are primary. Zhang Zhongjing's Mengchong Wan (Bug Pill) and Wenjing Tang (Warming the Menses Decoction) break blood to unblock Qi; once Qi flows, heat ceases steaming. This is a modified method for treating Heat. Sores rising with pus often involve fever, representing Qi steaming Blood. Abundant Qi causes Blood to transform according to Qi, forming pus. Without fever, Qi is weak, unable to steam pus; Huangqi (Astragali Radix), Guizhi (Cinnamomi Ramulus), and Fuzi (Aconiti Lateralis Radix) tonify Qi, assisting heat generation for Blood transformation. Vaccinia follows the same principle. This shows Heat belongs to the Qi aspect, differing from Fire belonging to the Blood aspect. Hence, Ou zhi (Lotus Rhizome Juice), Li zhi (Pear Juice), Laifu zhi (Radish Juice), Watermelon, Zhenzhu (Pearl), Shuijingshi (Quartz), Yuanjingshi (Plumbum), and Hanshui shi (Halloysitum Rubrum) all obtain Water Qi to clear Heat.
Q: Blood belongs to Fire, Qi belongs to Water. Now it is said Heat belongs to the Qi aspect. Why does the Heart govern Heat Qi and yet generate Blood?
A: The Heart in the human body is like the Sun in the sky. Heavenly Yang generates Earth Fire; thus, taking fire from the sun generates Fire attached to Wood. The Heart Meridian transforms fluids to generate Blood, which returns to the Liver. Therefore, the Liver and Pericardium/Gallbladder draw on Minister Fire, while Shaoyin Heart and Kidney alone govern Heat Qi. Cases of Minister Fire assisting Heat are treated with clearing agents like Huangqin (Scutellariae Radix) and Huanglian (Coptidis Rhizoma), or attacking agents like Xiaoshi (Natrii Sulfas) and Dahuang (Rhei Radix et Rhizoma), treating Heat while addressing Fire, akin to summer heat plus a stove fire. Cases of Heat assisting Minister Fire are like sun-baked volcanoes or wind-fanned torches; differentiation should follow this analogy. Discussing the Five Zang organs, the Heart belongs to Fire; discussing the Six Qi, Heart and Kidney both govern Yang Heat, while Fire belongs to Shaoyang. They can be separated or combined, requiring careful differentiation.
Q: Heavenly Yang generates Earth Fire, so the Heart generates Minister Fire of the Pericardium. Pericardium Blood stores in the Liver, so the Liver houses Minister Fire, embodying the unity of Wood and Fire. Yet the Pericardium and Liver are named Jueyin Meridians, collectively termed Wind Qi, not Minister Fire. Only Shaoyang Gallbladder and Sanjiao speak of Fire. Lord Fire and Minister Fire are later theories, inconsistent with the Six Qi. How should they be treated?
A: Calling the Pericardium Minister Fire is a later theory, not the original meaning of the *Neijing*. The *Neijing* only states: "The Chest Middle (Dan Zhong) is the official of the messenger, from whom joy arises." It implies the Heart distributes transformation; smooth blood vessels bring joy. Those with sufficient blood do not fear cold, showing Blood belongs to Heat, while Qi does not exclusively belong to Fire. Thus, Liver and Pericardium are not called Minister Fire. Only because the Pericardium connects with the Sanjiao can Sanjiao Fire combine with the Pericardium. The Liver connects with the Gallbladder, hence "Liver can transform into Fire." Ultimately, Fire Qi fully归属于 the Gallbladder, as it is Fire born from Wood. The Gallbladder connects to the Liver diaphragm, communicating with membranes, which is the Sanjiao. The transformation of Gallbladder Fire occurs entirely in the Sanjiao, moving through the network membranes; thus, Gallbladder and Sanjiao jointly govern Minister Fire. Counterflow qi with bitter vomiting is treated primarily with Huangqin (Scutellariae Radix); bitter and green, it enters the Gallbladder. Chaihu (Bupleuri Radix) obtains Wood Qi to penetrate and reach, preventing Fire stagnation. Heluye (Nelumbinis Folium) also clears and disperses Gallbladder Fire, resembling the Zhen trigram and having a bitter taste. Qingdai (Indigo Naturalis) is green and bitter, clearing Sanjiao Liver-Gallbladder Fire; its light quality treats throat conditions. The *Neijing* indicates that the binding of Two Yin (Shaoyin) and One Yang (Shaoyang) causes throat bi. Two Yin is Shaoyin, governing Heat; One Yang is Shaoyang, governing Fire-Heat. Their binding causes throat bi. Thus, treating throat conditions requires dispelling Fire and clearing Heat together. Lan ye (Isatidis Folium) treats Liver-Gallbladder Fire, slightly heavier than Qingdai. Haijinsha (Lygodii Spora) forms between leaves, resembling the Gallbladder attached to the Liver; its bitter taste clears Fire, making it essential for treating sand strangury. Sanjiao connects with the Gallbladder; only when Gallbladder Minister Fire binds does Sanjiao Water bind. This herb resolves binding with binding, thus treating it. Wubeizi (Galla Chinensis) also has seeds between leaves, with a salty taste providing moistening and descending action, moistening and removing Phlegm-Fire in the Lung. It also clears the Gallbladder due to seeds between leaves. It clears the Sanjiao because the Sanjiao roots in the Kidney system, and Wubeizi's salinity enters the Kidney. Sangjisheng (Taxilli Caulis et Folium) grows attached to wood, resembling the Gallbladder attached to the Liver; sour and bitter, it obtains Wood-Fire flavors, clearing Gallbladder Fire and treating wind-heat sinew bindings. The Gallbladder connects to Sanjiao membranes, externally linking to sinews; Sangjisheng vines attach to wood, resembling human sinews. Longdancao (Gentianae Radix) is bitter with many roots, descending Gallbladder and Sanjiao Fire. Huhuanglian (Coptidis Rhizoma alternative/Huanglian species?) is hollow, like Huangqin, accessing hollow membrane cavities; extremely bitter, it correctly treats Minister Fire, thus treating consumption steaming. This bitterness differs from Huanglian. Huanglian obtains the true bitter flavor, entering the Heart to purge Heat. Longdancao and Huhuanglian obtain bitter-acid altered flavors, entering Liver-Gallbladder and Sanjiao. Xiakucao (Prunella Spica) inherits Spring Shaoyang Qi, withering in Summer; bitter, it clears Liver-Gallbladder and Sanjiao Fire. Luoli (scrofula) is a binding of sinews on the head top. This herb grows creeping, resembling sinews; its light floating nature ascends to the Upper Jiao, treating neck bindings. Being harvested when withered implies consumption. Qinghao (Artemisiae Annuae Herba) is green and bitter, withering Liver-Gallbladder Minister Fire. Red worms must grow in its nodes, insects born from Wind influence; thus, Qinghao is a wind-dispelling and heat-clearing herb. Human consumption worms arise from Liver Qi and Minister Fire fanning each other, borrowing Blood to form substance; bone steaming must occur before worms generate. Qinghao nodes use insects to kill insects, eliminating stasis and steaming, borrowing insects to attack Blood and Wind Qi to disperse stagnant Fire. Fangji (Stephaniae Tetrandrae Radix) tastes like Longdancao and is hollow, penetrating membranes to clear Sanjiao Minister Fire and promote water flow. Gualou shi (Trichosanthis Fructus) seeds have oil and strong Qi; the pulp inside is bitter. Crushed and combined, they resolve diaphragmatic Phlegm-Fire. Shandougen (Sophorae Tonkinensis Radix) is white and bitter, entering the Lung to purge Fire. By Metal calming Wood, Fire does not rise and instead attacks Metal; thus, it treats sore throat. Throat conditions involve Shaoyin Heart and Sanjiao; Shandougen treats Wood-Fire, thereby treating the Sanjiao. Machixian (Portulacae Herba) contains mercury in leaves, obtaining Metal-Water nature; sour and cold, it clears Sanjiao Fire to promote water flow. Liyu dan (Carp Gallbladder) and Qingyu dan (Black Carp Gallbladder) enter Liver-Gallbladder by similarity; bitter and aquatic, they perfectly obtain Water nature, serving as primary drugs for Liver-Gallbladder Fire. Yan hou mu (rock throat eye conditions): Xiong (Bear) lives in mountains, fur-bearing animals inherit Wind nature, and gallbladder is extremely bitter; thus, it enters Liver-Gallbladder to clear Fire and treat throat/eye conditions. Digupi (Lycii Cortex) is thick like human membranes, bitter and cold, clearing Sanjiao Fire. Sanjiao and Gallbladder jointly govern Minister Fire, but Sanjiao roots in the Kidney. Kidney Yang Qi ascends via the Sanjiao pathway, so the Kidney can transfer Heat to the Sanjiao. Digupi penetrates deep into soil, obtaining Qi from underground springs, thus clearing Heat in Kidney Water and draining Mingmen Heat.