者之阳不足，复遇阴盛，阴气盛而阻其阳气运行之机，阴阳相攻，而腹痛大作，实阳衰太盛，不能敌其群阴，有以致之也。法宜扶阳抑阴，方用附子理中汤加砂、半，方解见上。
问曰：平人觉未有病，惟小便后有精如丝不断，甚则时滴不止者，何故？
答曰：此先天之阳衰，不能束精窍也。夫精窍与尿窍有别，尿窍易启，只要心气下降，即开而溺出。精窍封锁严密，藏于至阴之地，非阳极不开。今平人小便后有精不断者，其人必素禀阳虚，过于房劳，损伤真气，真气日衰，封锁不固，当心火下降，溺窍开而精窍亦与之俱开也。法宜大补元阳，交济心肾为主。方用白通汤，解见上。
答曰：此下焦之元阳未藏，而阴气未敛也。夫人身上、中、下三部，全是一团真气布护。今上、中俱平，而下部独病。下部属肾，肾通于两脚心涌泉穴，先天之真阳寄焉，故曰阳者，阴之根也。阳气充足，则阴气全消，百病不作；阳气散漫，则阴邪立起，浮肿如冰之症即生。古人以阳气喻龙，阴血喻水，水之汜滥，与水之归壑，其权操之龙也。龙升则水升，龙降则水降，此二气互根之妙，亦盈虚消长之机关也。学者苟能识得元阳飞潜之道，何患治肿之无方哉？法宜峻补元阳，交通上下，上下相交，水火互根，而浮肿自退矣。方用白通汤主之，解见上。
问曰：少阴病吐利，手足逆冷，烦躁欲死者，以吴茱萸汤主之，其故何也？
答曰：吐则亡阳（阳指胃阳），利则亡阴（阴指脾阴），中宫之阴阳两亡，阳气不能达于四末，故逆冷。中宫为上下之枢机，上属手少阴君火离也，而戊土寄焉（戊土属胃）。下属足少阴肾水坎也，而己土寄焉（己土属脾）。二土居中，一运精液于上而交心，一运精液于下而交肾，今因吐利过盛，二土骤虚，不能运精液而交通上下，故烦躁欲死。盖烦出于心，躁①出于肾，仲景所以列于少阴也。使吐利不至烦躁欲死，亦不得以少阴目之。主以吴茱萸汤，其旨微矣。
用药意解
按吴茱萸汤一方，乃温中、降逆，补肝之剂也。夫吴萸辛温，乃降逆补肝之品，逆气降而吐自不作，即能补中。肝得补而木气畅达，即不侮土，又与生姜之辛温同声相应，合大枣之甘，能调胃阳，复得人参甘寒，功专滋养脾阴。二土得补，皆具生机，转运复行，烦躁自然立止。此方重在补肝降逆以安中，中安而上下自定，握要之法，与理中汤意同而药不同也。理中汤浅一层，病人虽吐利，未至烦躁，故酌重在太阴；此方深一层，病人因吐利而至烦躁欲死，烦属心，躁属肾，故知其为少阴病。总由吐利太甚，中土失职，不能交通上下。其致吐之源，却由肝木凌土而成，故仲景主以吴茱萸汤，温肝降逆以安中，是的确不易之法，亦握要之法也。
问曰：病人牙齿肿痛二三日，忽皮肤大热，而内却冷，甚欲厚被覆体，有时外热一退，即不畏寒者，何故？
答曰：此元气外越而不潜藏故也。夫病人牙齿肿痛二三日，并无阳症可凭，已知其阴盛而元气浮也。以后皮肤大热，而内冷甚，明明元气尽越于外，较牙痛更加十倍。有时外热一退，即不畏寒者，是阳又潜于内故也。病人若恶寒不甚，发热身疼，即是太阳寒伤营卫之的症。畏寒太甚，而至厚被覆体，外热又甚，即不得以伤寒目之，当以元气外浮为主，用药切不可错误。此症又与上热下寒同，但上、下、内、外稍异耳。病形虽异，总归一元。法宜回阳，交通上下为主。方用白通汤、四逆汤，解见上。若兼头、项、腰、背痛，恶寒，于四逆汤内稍加麻、桂、细辛亦可。医于此地，不可猛浪，务要察透，方可主方，切切留意。
答曰：此元气虚极，浊阴之气上干，脾肾欲绝之征也。夫病人大病已久，元气之不足可知。元气之根在肾，培根之本在脾。脾肾欲绝，其气涣散，上干清道，直犯胃口，上下气机有不相接之势，故呃逆不止。人事昏沉，由元气衰极，不能支持。此等病形，阴象全现，非若胃火之呃逆，而饮水亦可暂止。法宜回阳降逆为主，方用吴萸四逆汤,或理中汤加吴萸亦可，解见上。
问曰：病人腰痛，身重，转侧艰难，如有物击，天阴雨则更甚者，何故？
答曰：此肾中之阳不足，而肾中之阴气盛也。夫腰为肾之府，先天之元气寄焉。元气足则肾脏温和，腰痛之疾不作。元气一亏，肾脏之阴气即盛。阴主静，静则寒湿丛生，元气微而不运，气滞不行，故痛作。因房劳过度而损伤元气者，十居其八；因寒邪入腑，阻其流行之机者，十有二三。由房劳过度者，病人两尺必浮空，面色必黑暗枯槁。由感寒而成者，两尺必浮紧有根，兼发热、头痛、身痛者多。凡属身重，转侧艰难，如有物击，天雨更甚之人，多系肾阳不足所致，寒湿所致亦同，总在脉色上求之。若阴虚所致，必潮热口干、脉细微、内觉热，逢亢阳更甚。元气亏者，可与潜阳丹；湿气滞者，可与肾着汤；由感寒者，可与麻黄附子细辛汤；肾虚者，可与滋肾丸、封髓丹、潜阳丹。解见上。
用药意解
按肾着汤一方，乃温中除湿之方也。此方似非治腰痛之方，其实治寒湿腰痛之妙剂也。夫此等腰痛，由于湿成，湿乃脾所主也。因脾湿太甚，流入腰之外府，阻其流行之气机，故痛作。方中用白术为君，不但燥脾去湿，又能利腰脐之气。
佐以茯苓之甘淡渗湿，又能化气行水，导水湿之气，从膀胱而出。更得干姜之辛温以暖土气，土气暖而湿立消。复得甘草之甘以缓之，而湿邪自化为乌有矣。方中全非治腰之品，专在湿上打算。腰痛之由湿而成者，故可治也。学者切不可见腰治腰，察病之因，寻病之情，此处领略方可。
按麻黄附子细辛汤一方，乃交阴阳之方，亦温经散寒之方也。夫附子辛热，能助太阳之阳，而内交于少阴。麻黄苦温，细辛辛温，能启少阴之精而外交于太阳，仲景取微发汗以散邪，实以交阴阳也。阴阳相交，邪自立解，若执发汗以论此方，浅识此方也。又曰温经散寒：温经者，温太阳之经；散寒者，散太阳之寒。
若此病腰痛，乃由寒邪入太阳之外府，阻其少阴出外之气机，故腰痛作。少阴与太阳为一表一里，表病及里，邪留于阴阳交气之中，故流连不已。今得附子壮太阳之阳，阳旺则寒邪立消。更得麻、细二物，从阴出阳，而寒邪亦与之俱出。阴阳两相鼓荡，故寒邪解而腰痛亦不作矣。
问曰：病人先二三日发吐未愈，遂渐畏寒，又二三日逢未刻即寒冷，冷后即发热，大汗出，至半夜乃已，日日如是，人渐不起，气促，诸医照疟症治之不效者，何故？
答曰：此由吐伤胃阳，胃阳欲亡也。夫病初起即发吐，病根已在于太阴。太阴与胃为表里，里病及表（胃为表，主容受；脾为里，主消磨。脾气不运，非因食伤，即因气阻。阻太过甚，则上逆而吐，吐则胃伤，过伤则亡阳），故吐。
吐则亡阳，故畏寒。复又大热出汗者，亡阳之征也。逢未而病起，至半夜而病止者，阳衰于午未，而生在子也。人事昏沉，气促渐不起，阳将亡而未亡也。诸医不察受病之根，专在寒热上分辨，故照疟法治之不愈。然疟症有外感、内伤之别，外感者，其人必发热、头痛、身痛，汗、吐、下后，而邪未尽，邪附于少阳，少阳居半表半里之间，邪出与阳争则热（阳指阳明）,邪入与阴争则寒（阴指太阴），寒疟（单寒无热）、热疟（单热无寒），即在此处攸分。亦有因饮食停滞中脘，气机遏郁不行，逢阳则热，逢阴则寒，其人必饱闷吞酸嗳腐为据，即食疟。若此病先由发呕吐（呕吐有因厥阴之气上干者，有胃欲绝者），渐冷、渐发热、出汗、气促、人沉迷，明明吐伤胃阳，故断之曰胃阳欲亡也。法宜急降逆温中回阳为主。回阳者，非回先天坎中之阳，而专回胃阳者（阳本一分而为三也）。方用吴茱萸汤，或吴萸四逆汤，或理中汤加吴萸俱可，解见上。
【阐释】此症先呕吐二三日，遂渐恶寒，继复大热汗出，渐至气促昏沉，程度逐渐加甚，郑氏辨明其与寒、热、食三种疟疾病象之不同，而断为吐伤胃阳，阳欲亡，半夜较轻，不过暂时宁静，实有独到之见。其治法是急降逆温中以回胃中之阳，故所出之方俱重用吴萸。诸医按疟疾施治，实有毫厘千里之谬，自无怪其不效。至于疟病，因其寒热之往来而决之于少阳也，故用小柴胡汤加减为正治。
笔者经验若发热多于发冷，汗出多，口渴甚，脉弦数者，加知母、石膏、花粉、黄连之类。若发冷多于发热，口渴不甚者，脉弦迟，加附子、干姜、桂枝。至于食疟，则用保和丸治之。无论其为热重、寒重或食疟，均于方中加入常山，其效更著。
问曰：病人前两月，上牙两边时时作疼，肝脉劲如石，脾脉亦有劲象，但不甚于肝部，后忽左边手足软弱，不能步履，麻木冷汗出，〔右边〕伸缩尚利，言语饮食如常者，何故？
答曰：此先天真气已衰，将脱而未脱之候也。近似中风，其实非中风也。夫病人上牙时时作疼，原系真气不藏，上冲所致，肝脾脉劲如石，先天之阳，欲附肝脾而出，暴脱之机关已具。后忽左边软弱，不能步履，麻木冷汗出者，是先天真气已衰于左，不复充盈。右边伸缩尚利者，后天脾胃之阳尚充，故也。昧者若作风治，更发散以耗其中气，中气立衰，命即不永。此际急宜保护后天，后天健旺，先天尚可复充。法宜先后并补为主，方用附子甘草汤，或加姜、桂、砂、半，缓缓调服，月余可瘳。解见上。
以上数十条，专论阳虚，指出先天真气上浮，反复推明。真气命根也，火种也，藏于肾中，立水之极，为阴之根，沉潜为顺，上浮为逆。病到真气上浮，五脏六腑之阳气，已耗将尽，消灭削剥，已至于根也。经云："凡五脏之病，穷必归肾"，即此说也。然真气上浮之病，往往多有与外感阳症同形，人多忽略，不知真气上浮之病大象虽具外感阳症之形，仔细推究，所现定系阴象，绝无阳症之实据可验，学者即在此处留心，不可猛浪。细将上卷辨认阳虚、阴虚秘诀熟记，君、相二火解体贴，则阳虚之病于在上、在中、在下，阴虚之病于在上、在中、在下，皆可按法治之也。阳虚篇内所备建中、理中、潜阳、回阳、封髓、姜桂诸方，皆从仲景四逆汤一方搜出。仲景云："三阳经病者，邪从阳化，阳盛则阴必亏，以存阴为要"，滋阴降火说所由来也；"三阴经病，邪入多从阴化，阴盛则阳必衰，以回阳为先"，益火之源以消阴翳所由起也。大凡阳虚之人，阴气自然必盛，阴气盛必上腾，即现牙疼、龈肿、口疮、舌烂、齿血、喉痛、大小便不利之病，不得妄以滋阴降火之法施之。若妄施之，是助阴以灭阳也，辨察不可不慎。总在这阴象上追求，如舌青、唇青、淡白无神之类是也。千古以来，混淆莫辨，含糊不清，聪明颖悟之人，亦仅得其半而遗其半，金针虽度，若未度也。故仲景一生心法，知之者寡。兹采取数十条，汇成一册，以便后学参究。其中一元妙义，消长机关，明明道破。至于仲景六经主方，乃有一定之至理，变方、加减方，乃是随邪之变化而用也。三阳之方，以升散、清、凉、汗、吐、下为准。三阴之方，以温中、收纳、回阳、降逆、封固为要。阴阳界限，大有攸分。以三阳之方治三阳病，虽失不远；以三阳之方治三阴病，则失之远矣。世之业斯道者，书要多读，理要细玩，人命生死，在于反掌之间，此理不明，切切不可妄主方药，糊口事小，获罪事大。苟能细心研究，自问无愧，方可言医。
客疑篇
客有疑而问曰：先生论阳虚数十条，皆曰此本先天一阳所发为病也。夫人以心为主，心，火也、阳也。既曰阳虚，何不着重在上之君火，而专在以下之真火乎？余曰：大哉斯问也，子不知人身立命，其有本末乎？本者何？就是这水中天，一句了了，奈世罕有窥其蕴者，不得不为之剖晰。尝谓水火相依而行（水即血也，阴也；火即气也，阳也），虽是两物，却是一团，有分之不可分，合之不胜合者也。即以一杯沸水为喻（沸，热气也，即水中无形之真火），气何常离乎水，水何常离乎气？
患者阳气不足，又遭遇阴气过盛，阴气旺盛阻碍了阳气运行的机制，阴阳相互攻伐，导致腹部剧烈疼痛，这实际上是阳气衰微而阴寒太盛，无法抵御群阴所致。治疗法则应当扶助阳气、抑制阴气，方剂选用附子理中汤加砂仁、半夏，方解见上文。
问：普通人自觉没有生病，只是在小便后有精液如丝线般不断流出，严重时甚至不时滴沥不止，这是什么原因？
答：这是先天阳气衰微，不能固摄精窍的缘故。精窍与尿窍不同，尿窍容易开启，只要心气下降，就会打开并排出尿液。精窍封锁严密，藏于至阴之地，非阳气极盛不会开启。现在普通人在小便后有精液不断流出，此人必定素体阳虚，加之房事过度，损伤了真气，真气日渐衰微，封锁不牢固，当心火下降时，尿窍开启，精窍也随之一起开启。治疗法则应当大补元阳，使心肾相交济为主。方剂选用白通汤，方解见上文。
答：这是下焦的元阳未能潜藏，而阴气未能收敛的缘故。人体上、中、下三部，全是一团真气布护。如今上、中部都正常，唯独下部生病。下部属肾，肾通于两脚心的涌泉穴，先天的真阳寄居于此，所以说“阳是阴的根本”。阳气充足，则阴气全消，百病不生；阳气散漫，则阴邪立刻兴起，浮肿如冰的症状就会产生。古人将阳气比喻为龙，阴血比喻为水，水的泛滥或归壑，其权柄掌握在龙手中。龙升则水升，龙降则水降，这是二气互根的奥妙，也是盈亏消长的关键。学者如果能识得元阳飞潜的道理，还担心治疗浮肿没有方法吗？治疗法则应当峻补元阳，交通上下，上下相交，水火互根，浮肿自然消退。方剂选用白通汤主治，方解见上文。
问：少阴病出现呕吐腹泻，手足逆冷，烦躁欲死，用吴茱萸汤主治，这是什么缘故？
答：呕吐则亡失胃阳（阳指胃阳），腹泻则亡失脾阴（阴指脾阴），中焦脾胃的阴阳两亡，阳气不能到达四肢末端，所以手足逆冷。中焦是上下气机的枢纽，上部属于手少阴君火离卦，而戊土寄寓其中（戊土属胃）。下部属于足少阴肾水坎卦，而己土寄寓其中（己土属脾）。二土居中，一者运化精液向上交于心，一者运化精液向下交于肾，如今因呕吐腹泻过于严重，二土骤然虚弱，不能运化精液以交通上下，所以烦躁欲死。大概烦出于心，躁①出于肾，张仲景因此将其列在少阴病中。如果呕吐腹泻不至于烦躁欲死，也不能将其归为少阴病。主用吴茱萸汤，其中的旨意微妙啊。
用药意解
按吴茱萸汤这一方，是温中、降逆、补肝的方剂。吴茱萸辛温，是降逆补肝的药物，逆气下降则呕吐自然停止，也就能够补中。肝得到补益则木气畅达，就不会克制脾土，又与生姜的辛温同声相应，配合大枣的甘味，能调和胃阳，再加上人参的甘寒，功效专门滋养脾阴。二土得到补益，都具有生机，转运功能恢复，烦躁自然立刻停止。此方重在补肝降逆以安中，中焦安宁则上下自然安定，这是握要的方法，与理中汤的意思相同但药物不同。理中汤浅一层，病人虽然呕吐腹泻，但未到烦躁的程度，所以酌情重在太阴；此方深一层，病人因呕吐腹泻而至烦躁欲死，烦属心，躁属肾，所以知道这是少阴病。总由呕吐腹泻太甚，中土失职，不能交通上下。导致呕吐的源头，却是由肝木克伐脾土而成，所以张仲景主用吴茱萸汤，温肝降逆以安中，这是确切不易的方法，也是握要的方法。
问：病人牙齿肿痛二三天，忽然皮肤大热，而体内却冷，非常想盖厚被子覆盖身体，有时外热一退，就不怕冷了，这是什么原因？
答：这是元气外越而不能潜藏的缘故。病人牙齿肿痛二三天，并没有阳症可以凭据，已经知道是阴盛而元气浮越。之后皮肤大热，而体内极冷，明明是元气全部外越于体表，比牙痛更加十倍。有时外热一退，就不怕冷了，这是阳气又潜藏于体内的缘故。病人如果恶寒不严重，发热身疼，就是太阳寒伤营卫的确切症状。畏寒太甚，以至于盖厚被子覆盖身体，外热又很厉害，就不能将其当作伤寒来看待，应当以元气外浮为主，用药切不可错误。此症又与上热下寒相同，只是上、下、内、外稍有差异罢了。病形虽然不同，总归于一元之气。治疗法则应当回阳，交通上下为主。方剂选用白通汤、四逆汤，方解见上文。如果兼有头、项、腰、背痛，恶寒，在四逆汤内稍加麻黄、桂枝、细辛也可以。医生在此处，不可鲁莽，务必观察透彻，才可以主方，切记留意。
答：这是元气极度虚弱，浊阴之气上犯，脾肾即将衰竭的征象。病人患大病已久，元气的不足是可以知道的。元气的根在肾，培根的本在脾。脾肾欲绝，其气涣散，上犯清道，直犯胃口，上下气机有不相接续的趋势，所以呃逆不止。人事昏沉，是由于元气衰极，不能支撑。这种病形，阴象完全显现，不像胃火引起的呃逆，喝水也可以暂时停止。治疗法则应当回阳降逆为主，方剂选用吴萸四逆汤，或者理中汤加吴茱萸也可以，方解见上文。
问：病人腰痛，身体沉重，转侧艰难，好像有东西击打，天阴下雨时更严重，这是什么原因？
答：这是肾中的阳气不足，而肾中的阴气过盛的缘故。腰是肾的府邸，先天的元气寄居于此。元气充足则肾脏温和，腰痛之疾不发生。元气一旦亏损，肾脏的阴气就旺盛。阴主静，静则寒湿丛生，元气微弱而不运行，气滞不行，所以疼痛发作。因房劳过度而损伤元气的，占十分之八；因寒邪入腑，阻碍其流行机制的，占十分之二三。由房劳过度引起的，病人的两尺脉必浮空，面色必黑暗枯槁。由感受寒邪引起的，两尺脉必浮紧有根，兼有发热、头痛、身痛的较多。凡是属于身体沉重，转侧艰难，好像有东西击打，雨天更严重的人，多系肾阳不足所致，寒湿所致也相同，总在脉色上寻求。如果是阴虚引起的，必有潮热口干、脉细微、内觉热，逢亢阳时更严重。元气亏虚者，可与潜阳丹；湿气滞留者，可与肾着汤；由感受寒邪者，可与麻黄附子细辛汤；肾虚者，可与滋肾丸、封髓丹、潜阳丹。方解见上文。
用药意解
按肾着汤这一方，是温中除湿的方剂。此方似乎不是治腰痛的方子，其实是治疗寒湿腰痛的妙剂。这种腰痛，由于湿邪引起，湿乃脾所主。因脾湿太甚，流入腰的外府，阻碍其流行的气机，所以疼痛发作。方中用白术为君药，不但燥脾去湿，又能利腰脐之气。
佐以茯苓的甘淡渗湿，又能化气行水，引导水湿之气，从膀胱而出。再得干姜的辛温以暖土气，土气暖而湿立消。又得甘草的甘味以缓之，而湿邪自然化为乌有。方中全非治腰的药物，专在湿上打算。腰痛由湿引起的，所以可以治疗。学者切不可见腰治腰，察看病的原因，寻找病的情状，此处领悟才可以。
按麻黄附子细辛汤这一方，是交阴阳的方剂，也是温经散寒的方剂。附子辛热，能助太阳之阳，而内交于少阴。麻黄苦温，细辛辛温，能启少阴之精而外交于太阳，张仲景取微发汗以散邪，实则是为了交阴阳。阴阳相交，邪气自然解除，如果执着于发汗来论述此方，是浅识此方。又说温经散寒：温经者，温太阳之经；散寒者，散太阳之寒。
如果此病腰痛，乃由寒邪入太阳之外府，阻碍其少阴出外的气机，所以腰痛发作。少阴与太阳为一表一里，表病及里，邪留于阴阳交气之中，所以流连不已。如今得附子壮太阳之阳，阳旺则寒邪立消。再得麻、细二物，从阴出阳，而寒邪也与之俱出。阴阳两相鼓荡，所以寒邪解而腰痛也不发作了。
问：病人先二三天发生呕吐未愈，逐渐畏寒，又二三天逢未时即寒冷，冷后即发热，大汗出，至半夜才停止，日日如此，人渐渐起不来，气促，各位医生照疟症治疗无效，这是什么原因？
答：这是由呕吐损伤胃阳，胃阳将要亡失的缘故。病初起即发生呕吐，病根已在于太阴。太阴与胃为表里，里病及表（胃为表，主容受；脾为里，主消磨。脾气不运，非因食伤，即因气阻。阻太过甚，则上逆而吐，吐则胃伤，过伤则亡阳），所以呕吐。
呕吐则亡阳，所以畏寒。后来又大热出汗，是亡阳的征象。逢未时而病起，至半夜而病止，是因为阳衰于午未，而生在子时。人事昏沉，气促渐渐起不来，是阳将亡而未亡。各位医生不察看受病的根本，专门在寒热上分辨，所以照疟法治之不愈。然而疟症有外感、内伤的区别，外感者，其人必发热、头痛、身痛，汗、吐、下后，而邪未尽，邪附于少阳，少阳居半表半里之间，邪出与阳争则热（阳指阳明）,邪入与阴争则寒（阴指太阴），寒疟（单寒无热）、热疟（单热无寒），即在此处区分。也有因饮食停滞中脘，气机遏郁不行，逢阳则热，逢阴则寒，其人必饱闷吞酸嗳腐为依据，即食疟。若此病先由发呕吐（呕吐有因厥阴之气上犯者，有胃欲绝者），渐冷、渐发热、出汗、气促、人沉迷，明明是吐伤胃阳，所以断定为胃阳欲亡。治疗法则应当急降逆温中回阳为主。回阳者，非回先天坎中之阳，而专回胃阳者（阳本一分而为三也）。方剂选用吴茱萸汤，或吴萸四逆汤，或理中汤加吴茱萸都可以，方解见上文。
【阐释】此症先呕吐二三天，遂渐恶寒，继复大热汗出，渐至气促昏沉，程度逐渐加重，郑氏辨明其与寒、热、食三种疟疾病象的不同，而断为吐伤胃阳，阳欲亡，半夜较轻，不过是暂时宁静，实有独到之见。其治法是急降逆温中以回胃中之阳，故所出之方俱重用吴茱萸。各位医生按疟疾施治，实有毫厘千里之谬，自无怪其不效。至于疟病，因其寒热之往来而决之于少阳也，故用小柴胡汤加减为正治。
笔者经验若发热多于发冷，汗出多，口渴甚，脉弦数者，加知母、石膏、花粉、黄连之类。若发冷多于发热，口渴不甚者，脉弦迟，加附子、干姜、桂枝。至于食疟，则用保和丸治之。无论其为热重、寒重或食疟，均于方中加入常山，其效更著。
问：病人前两月，上牙两边时时作疼，肝脉劲如石，脾脉亦有劲象，但不甚于肝部，后忽左边手足软弱，不能步履，麻木冷汗出，〔右边〕伸缩尚利，言语饮食如常，这是什么原因？
答：这是先天真气已衰，将脱而未脱的候象。近似中风，其实不是中风。病人上牙时时作疼，原系真气不藏，上冲所致，肝脾脉劲如石，先天之阳，欲附肝脾而出，暴脱的机关已具备。后来忽然左边软弱，不能步履，麻木冷汗出，是先天真气已衰于左，不复充盈。右边伸缩尚利的，是后天脾胃之阳尚充，所以如此。愚昧之人若作风证治疗，更发散以耗其中气，中气立刻衰败，性命即不长久。此时急宜保护后天，后天健旺，先天尚可复充。治疗法则应当先后并补为主，方剂选用附子甘草汤，或加姜、桂、砂、半，缓缓调服，月余可痊愈。方解见上文。
以上数十条，专论阳虚，指出先天真气上浮，反复推明。真气是命根，是火种，藏于肾中，立于水之极，为阴之根，沉潜为顺，上浮为逆。病到真气上浮，五脏六腑的阳气，已耗将尽，消灭削剥，已至于根。经云：“凡五脏之病，穷必归肾”，即此说也。然而真气上浮的病，往往多有与外感阳症同形，人多忽略，不知真气上浮的病大象虽具外感阳症之形，仔细推究，所现定系阴象，绝无阳症之实据可验，学者即在此处留心，不可鲁莽。细将上卷辨认阳虚、阴虚秘诀熟记，君、相二火解体贴，则阳虚的病在上、在中、在下，阴虚的病在上、在中、在下，皆可按法治之。阳虚篇内所备建中、理中、潜阳、回阳、封髓、姜桂诸方，皆从仲景四逆汤一方搜出。仲景云：“三阳经病者，邪从阳化，阳盛则阴必亏，以存阴为要”，滋阴降火说所由来也；“三阴经病，邪入多从阴化，阴盛则阳必衰，以回阳为先”，益火之源以消阴翳所由起也。大凡阳虚之人，阴气自然必盛，阴气盛必上腾，即现牙疼、龈肿、口疮、舌烂、齿血、喉痛、大小便不利之病，不得妄以滋阴降火之法施之。若妄施之，是助阴以灭阳也，辨察不可不慎。总在这阴象上追求，如舌青、唇青、淡白无神之类是也。千古以来，混淆莫辨，含糊不清，聪明颖悟之人，亦仅得其半而遗其半，金针虽度，若未度也。故仲景一生心法，知之者寡。兹采取数十条，汇成一册，以便后学参究。其中一元妙义，消长机关，明明道破。至于仲景六经主方，乃有一定之至理，变方、加减方，乃是随邪之变化而用也。三阳之方，以升散、清、凉、汗、吐、下为准。三阴之方，以温中、收纳、回阳、降逆、封固为要。阴阳界限，大有攸分。以三阳之方治三阳病，虽失不远；以三阳之方治三阴病，则失之远矣。世之业斯道者，书要多读，理要细玩，人命生死，在于反掌之间，此理不明，切切不可妄主方药，糊口事小，获罪事大。苟能细心研究，自问无愧，方可言医。
客疑篇
客人有疑问问道：先生论阳虚数十条，都说这是本源于先天一阳所引发的病。人以心为主，心，是火，是阳。既然说是阳虚，为什么不着重在上部的君火，而专在下部的真火呢？我说：这个问题太伟大了，你不知道人身立命，是有本末的吗？本是什么？就是这水中天，一句话就能明了，无奈世间很少有人窥探其中的蕴奥，不得不为之剖析。曾谓水火相依而行（水即血，阴；火即气，阳），虽然是两物，却是一团，有分之不可分，合之不胜合者也。就以一杯沸水为比喻（沸，热气，即水中无形之真火），气何尝离开水，水何尝离开气？
The patient's Yang Qi is insufficient, and upon encountering excessive Yin Qi, the flourishing Yin obstructs the mechanism of Yang Qi circulation. The mutual attack between Yin and Yang results in severe abdominal pain. This is actually caused by extreme deficiency of Yang Qi and excess of Yin Cold, which cannot resist the multitude of Yin pathogens. The treatment principle should be to support Yang and suppress Yin. The formula used is Fuzi Lizhong Tang (Aconite Root and Magnolia Bark Decoction) with added Sha Ren (Amomum Fruit) and Ban Xia (Pinellia Tuber). The explanation of the formula is seen above.
Question: A healthy person feels no illness, but after urination, semen flows out continuously like threads, and in severe cases, it drips intermittently. What is the reason?
Answer: This is due to the deficiency of congenital Yang Qi, which fails to secure the essence orifice. The essence orifice differs from the urine orifice; the urine orifice opens easily as long as Heart Qi descends, allowing urine to flow out. The essence orifice is tightly sealed and resides in the most Yin region, opening only when Yang Qi reaches an extreme state. Now, if a healthy person has continuous semen discharge after urination, this person must have had a constitutionally deficient Yang, compounded by excessive sexual activity that damaged the True Qi. As True Qi declines daily, the sealing mechanism becomes insecure. When Heart Qi descends, the urine orifice opens, and the essence orifice opens simultaneously. The treatment principle should focus on greatly supplementing Yuan Yang (Original Yang) to facilitate the interaction between Heart and Kidney. The formula used is Baitong Tang (White Tongue Decoction). The explanation of the formula is seen above.
Question: After an illness, both legs swell up to the knees and feel cold as ice. What is the reason?
Answer: This is because the Yuan Yang of the Lower Jiao has not been stored, and Yin Qi has not converged. The upper, middle, and lower parts of the human body are all protected by a mass of True Qi. Currently, the upper and middle parts are normal, while only the lower part is diseased. The lower part belongs to the Kidney, which connects to the Yongquan acupoint (Kidney-1) at the soles of the feet, where congenital True Yang resides. Therefore, it is said that "Yang is the root of Yin." When Yang Qi is sufficient, Yin Qi is entirely eliminated, and hundred diseases do not arise; when Yang Qi scatters, Yin pathogens immediately rise, causing symptoms such as edema and coldness like ice. Ancients compared Yang Qi to a dragon and Yin Blood to water. Whether water floods or returns to its channel depends on the dragon. When the dragon rises, water rises; when the dragon descends, water descends. This is the subtlety of the mutual root of these two energies and the mechanism of waxing and waning. If scholars can understand the way of the flying and diving Yuan Yang, why worry about lacking methods to treat edema? The treatment principle should be to vigorously supplement Yuan Yang and facilitate communication between the upper and lower. When the upper and lower interact, and Water and Fire mutually root each other, the edema will naturally recede. The formula used as the main treatment is Baitong Tang. The explanation of the formula is seen above.
Question: In Shaoyin disease, vomiting and diarrhea occur, accompanied by cold limbs and extreme restlessness. Why is Wuzhuyu Tang (Evodia Decoction) used as the main treatment?
Answer: Vomiting leads to the loss of Stomach Yang (Yang refers to Stomach Yang), and diarrhea leads to the loss of Spleen Yin (Yin refers to Spleen Yin). With the simultaneous loss of Yin and Yang in the Middle Jiao, Yang Qi cannot reach the four extremities, resulting in cold limbs. The Middle Jiao is the pivot for the upper and lower. The upper belongs to the Hand Shaoyin Ministerial Fire (Li Trigram), where Wu Earth resides (Wu Earth belongs to the Stomach). The lower belongs to the Foot Shaoyin Kidney Water (Kan Trigram), where Ji Earth resides (Ji Earth belongs to the Spleen). These two Earths reside in the center; one transports essence fluids upward to interact with the Heart, and the other transports essence fluids downward to interact with the Kidney. Now, due to excessive vomiting and diarrhea, the two Earths become suddenly deficient and cannot transport essence fluids to communicate between the upper and lower, leading to extreme restlessness. Generally, "Fan" (mental agitation) originates from the Heart, and "Zao" (physical restlessness) originates from the Kidney. Zhang Zhongjing therefore classified this under Shaoyin disease. If vomiting and diarrhea do not lead to extreme restlessness, they cannot be categorized as Shaoyin disease. Using Wuzhuyu Tang as the main treatment reveals profound intent.
Wuzhuyu Tang
Evodia Fruit 1 Sheng, Ginseng Root 3 Liang, Fresh Ginger 6 Liang, Jujube 12 pieces.
Explanation of Medicinal Intent
According to Wuzhuyu Tang, this is a formula for warming the middle, descending rebellious Qi, and tonifying the Liver. Evodia Fruit is pungent and warm, serving to descend rebellious Qi and tonify the Liver. When rebellious Qi descends, vomiting stops, thereby benefiting the middle. When the Liver is tonified, Wood Qi flows freely and does not overact on Earth. It resonates with the pungent warmth of Fresh Ginger. Combined with the sweetness of Jujube, it harmonizes Stomach Yang. Added with the sweet-cool properties of Ginseng Root, its function specializes in nourishing Spleen Yin. With the two Earths tonified, vitality is restored, transport functions resume, and restlessness naturally ceases. This formula focuses on tonifying the Liver and descending rebellious Qi to calm the middle. When the middle is calm, the upper and lower stabilize. This is a method of grasping the key, similar in intent to Lizhong Tang but different in ingredients. Lizhong Tang is one step shallower; although the patient vomits and has diarrhea, there is no restlessness, so the focus is appropriately on the Taiyin stage. This formula is one step deeper; the patient experiences extreme restlessness due to vomiting and diarrhea. Since Fan belongs to the Heart and Zao belongs to the Kidney, it is known as Shaoyin disease. Ultimately, excessive vomiting and diarrhea cause the Middle Earth to fail in its duties, unable to communicate between the upper and lower. The source of vomiting lies in Liver Wood overacting on Earth. Therefore, Zhang Zhongjing uses Wuzhuyu Tang to warm the Liver, descend rebellious Qi, and calm the middle. This is indeed an unchangeable and key-grasping method.
Question: A patient suffers from tooth swelling and pain for two to three days, suddenly develops high skin temperature, yet feels cold inside, strongly desiring thick blankets, and sometimes when the external heat subsides, they no longer fear cold. What is the reason?
Answer: This is due to Yuan Qi floating outward and failing to store itself. The patient has had tooth swelling and pain for two to three days without any Yang syndrome evidence, indicating Yin excess and floating Yuan Qi. Subsequently, the skin becomes very hot while the interior is extremely cold, clearly showing that Yuan Qi has completely floated to the exterior, ten times worse than the tooth pain. Sometimes, when the external heat subsides, the patient no longer fears cold, indicating that Yang has returned to storing within the interior. If the patient has mild aversion to cold, fever, and body ache, these are definitive symptoms of Taiyin Cold injuring Ying and Wei. However, if aversion to cold is severe enough to require thick blankets, and external heat is intense, it cannot be classified as Cold Damage (Shanghan); it should be primarily viewed as floating Yuan Qi. Medication must not be erroneous. This condition is similar to Upper Heat and Lower Cold, differing only slightly in location. Although the clinical presentation varies, it ultimately returns to One Origin. The treatment principle should focus on restoring Yang and communicating between the upper and lower. The formulas used are Baitong Tang and Sini Tang (Four Reversal Decoction). The explanations of the formulas are seen above. If accompanied by headache, stiff neck, backache, and aversion to cold, adding Ephedra Stem, Cinnamon Twig, and Asarum Root to Sini Tang is also acceptable. Physicians must not act rashly here; thorough observation is required before prescribing. Take care.
Question: After a major illness has not healed, hiccups persist incessantly, accompanied by drowsiness. What is the reason?
Answer: This is a sign of extreme deficiency of Yuan Qi, with turbid Yin Qi attacking upward, indicating impending failure of the Spleen and Kidney. Having suffered from a major illness for a long time, the insufficiency of Yuan Qi is evident. The root of Yuan Qi is in the Kidney, and the foundation of this root is the Spleen. When Spleen and Kidney are about to fail, their Qi scatters, attacks the clear pathways upward, and directly invades the stomach area. There is a tendency for the upper and lower Qi mechanisms to disconnect, causing persistent hiccups. Mental drowsiness is due to extreme decline of Yuan Qi, unable to sustain life. This clinical presentation shows full Yin signs, unlike hiccups caused by Stomach Fire, which may temporarily stop with drinking water. The treatment principle should focus on restoring Yang and descending rebellious Qi. The formula used is Wuyu Sini Tang (Evodia and Four Reversal Decoction), or Lizhong Tang with added Evodia Fruit. The explanations of the formulas are seen above.
Question: A patient suffers from lower back pain, heavy body, difficulty turning, feeling as if being struck, worsening on cloudy or rainy days. What is the reason?
Answer: This is due to insufficient Yang Qi in the Kidney and excessive Yin Qi in the Kidney. The waist is the mansion of the Kidney, where congenital Yuan Qi resides. When Yuan Qi is sufficient, the Kidneys remain warm, and lower back pain does not occur. Once Yuan Qi is deficient, Kidney Yin Qi becomes excessive. Yin governs stillness; stillness generates cold-dampness. With weak and stagnant Yuan Qi, pain arises. Eight out of ten cases are caused by excessive sexual activity damaging Yuan Qi; two or three out of ten are caused by Cold Evil entering the Fu organs, obstructing circulation. In cases caused by excessive sexual activity, the radial pulses at both wrists (Chi position) will be floating and empty, and the complexion will be dark and withered. In cases caused by Cold invasion, the Chi pulses will be floating, tight, and rooted, often accompanied by fever, headache, and body ache. Anyone suffering from heavy body, difficulty turning, sensation of being struck, and worsening on rainy days is mostly due to Kidney Yang deficiency, though Cold-Damp causes similar symptoms. Diagnosis relies on pulse and complexion. If caused by Yin deficiency, there will be tidal fever, dry mouth, fine-thready pulse, internal heat sensation, worsening during extreme Yang periods. For Yuan Qi deficiency, Qianyang Dan (Submerge Yang Powder) can be given; for dampness stagnation, Shen Zhuo Tang (Spleen Fixation Decoction) can be given; for Cold invasion, Mahuang Fuzi Xixin Tang (Ephedra, Aconite, and Asarum Decoction) can be given; for Kidney deficiency, Zishen Wan (Nourish Kidney Pill), Fengsui Dan (Seal Marrow Pill), or Qianyang Dan can be given. Explanations of the formulas are seen above.
Shen Zhuo Tang
Atractylodes Macrocephala Rhizome 1 Liang, Poria 6 Qian, Dried Ginger 6 Qian, Prepared Licorice Root 3 Qian.
Mahuang Fuzi Xixin Tang
Ephedra Stem 8 Qian, Prepared Aconite Root 6 Qian, Asarum Root 3 Qian.
Explanation of Medicinal Intent
Shen Zhuo Tang is a formula for warming the middle and eliminating dampness. Although it seems not to treat lower back pain, it is actually a superb remedy for cold-damp lower back pain. Such lower back pain is caused by dampness, which is governed by the Spleen. Excessive Spleen dampness flows into the outer mansion of the waist, obstructing the circulating Qi mechanism, causing pain. Atractylodes Macrocephala Rhizome is used as the sovereign herb; it not only dries Spleen and eliminates dampness but also benefits the Qi of the waist and umbilicus. Poria, with its sweet-bland property, leaches out dampness and transforms Qi to move water, guiding dampness out through the Bladder. Dried Ginger adds pungent-warmth to warm the Earth Qi; when Earth Qi is warm, dampness dissipates instantly. Licorice Root adds sweetness to moderate the action, causing the damp pathogen to vanish. None of the herbs specifically target the waist; the focus is entirely on dampness. Since the lower back pain is caused by dampness, it can be treated. Scholars must not simply treat the waist; they must investigate the cause and nature of the disease.
Mahuang Fuzi Xixin Tang is a formula for interacting Yin and Yang, and also for warming meridians and dispersing cold. Aconite Root is pungent-hot, assisting Taiyang Yang to internally interact with Shaoyin. Ephedra Stem is bitter-warm, and Asarum Root is pungent-warm; together they awaken Shaoyin Essence to externally interact with Taiyang. Zhang Zhongjing uses mild sweating to disperse pathogens, essentially to interact Yin and Yang. When Yin and Yang interact, pathogens resolve themselves. Viewing this formula merely as a diaphoretic is a superficial understanding. Regarding warming meridians and dispersing cold: warming meridians refers to warming Taiyang meridians; dispersing cold refers to dispersing Taiyang cold. If lower back pain is caused by Cold Evil invading the outer mansion of Taiyang, obstructing the Qi mechanism of Shaoyin exiting outward, pain occurs. Shaoyin and Taiyang form an interior-exterior pair. Exterior disease affecting the interior leaves pathogens lingering in the intersection of Yin and Yang Qi, causing persistence. With Aconite strengthening Taiyang Yang, abundant Yang quickly eliminates cold pathogens. Ephedra and Asarum help exit from Yin to Yang, carrying cold pathogens out with them. The mutual stirring of Yin and Yang resolves the cold pathogen, and lower back pain ceases.
Question: A patient first experienced vomiting for two to three days without relief, then gradually developed aversion to cold. Two more days later, every day at Wei hour (1–3 PM), they felt cold, followed by fever, profuse sweating, ending at midnight. This repeated daily, leading to weakness, shortness of breath. Various physicians treated it as malaria without effect. What is the reason?
Answer: This is due to vomiting injuring Stomach Yang, leading to impending loss of Stomach Yang. The initial vomiting indicates the root of the disease lies in the Taiyin stage. Taiyin and Stomach are exterior-interior partners. Interior disease affecting the exterior (Stomach is exterior, governing reception; Spleen is interior, governing digestion. If Spleen Qi fails to transport, it is due to food injury or Qi obstruction. Severe obstruction causes upward rebellion and vomiting, injuring the Stomach. Excessive injury leads to Yang loss). Thus, vomiting occurs. Vomiting leads to Yang loss, hence aversion to cold. Subsequent high fever and sweating are signs of Yang loss. The onset at Wei hour and cessation at midnight reflect Yang declining at Wu-Wei hours and generating at Zi hour. Mental drowsiness, shortness of breath, and inability to rise indicate Yang is about to perish but has not yet done so. Physicians failed to examine the root of the disease, focusing only on distinguishing cold and heat, thus treating it as malaria without success. Malaria differs in exterior-invasion versus interior-injury types. Exterior invasion presents with fever, headache, body ache; after sweating, vomiting, or purging, if pathogens remain, they attach to Shaoyang, which resides between exterior and interior. Pathogens emerging contend with Yang (referring to Yangming) causing heat; pathogens entering contend with Yin (referring to Taiyin) causing cold. Cold malaria (cold only, no heat) and Heat malaria (heat only, no cold) are distinguished here. Also, food stagnation in the Middle Jiao obstructs Qi mechanism, causing heat when encountering Yang and cold when encountering Yin, characterized by fullness, acid regurgitation, and belching rotten food—this is Food Malaria. This case began with vomiting (caused by Jueyin Qi attacking upward or Stomach failing), followed by gradual cold, fever, sweating, shortness of breath, and coma. Clearly, vomiting injured Stomach Yang, leading to the conclusion of impending Stomach Yang loss. The treatment principle should urgently descend rebellious Qi, warm the middle, and restore Yang. Restoring Yang here refers not to restoring the congenital Yang in Kan (Kidney), but specifically to restoring Stomach Yang (Yang originally divides into three). Formulas used include Wuzhuyu Tang, Wuyu Sini Tang, or Lizhong Tang with added Evodia Fruit. Explanations of the formulas are seen above.
[Interpretation] This symptom began with vomiting for two to three days, followed by gradual aversion to cold, then high fever and sweating, progressing to shortness of breath and coma, worsening in severity. Zheng distinguishes this from the manifestations of Cold, Heat, and Food malaria, diagnosing it as vomiting injuring Stomach Yang with impending Yang loss. The slight improvement at midnight is merely temporary tranquility, demonstrating unique insight. The treatment urgently descends rebellious Qi and warms the middle to restore Stomach Yang, hence all prescribed formulas heavily use Evodia Fruit. Treating according to malaria was a significant error, explaining the lack of efficacy. For malaria, determined by alternating chills and fever in Shaoyang, Xiao Chaihu Tang (Minor Bupleurum Decoction) with modifications is the correct treatment.
Personal experience: If fever exceeds chills, with profuse sweating and severe thirst, and wiry-rapid pulse, add Anemarrhena Rhizome, Gypsum, Glehnia Root, and Coptis Rhizome. If chills exceed fever, with mild thirst, and wiry-slow pulse, add Prepared Aconite Root, Dried Ginger, and Cinnamon Twig. For Food Malaria, Baohe Wan (Preserve Harmony Pill) is used. Regardless of whether it is Heat-heavy, Cold-heavy, or Food Malaria, adding Polygala Root enhances efficacy.
Question: For the past two months, the sides of the upper teeth have periodically hurt. The Liver pulse is hard as stone, and the Spleen pulse also shows hardness, though less than the Liver. Suddenly, the left hand and foot became weak, unable to walk, numb, with cold sweat. [The right side] remains flexible, speech and diet are normal. What is the reason?
Answer: This is a sign that congenital True Qi has declined and is on the verge of collapse, though not yet collapsed. It resembles stroke, but is not stroke. Periodic upper tooth pain is caused by unconcealed True Qi rushing upward. The Liver and Spleen pulses being hard as stone indicate congenital Yang attempting to escape via the Liver and Spleen; the mechanism for sudden collapse is present. The subsequent left-sided weakness, inability to walk, numbness, and cold sweat show that congenital True Qi has declined on the left and is no longer充盈 (full). The right side remaining flexible indicates that postnatal Spleen-Stomach Yang is still sufficient. Ignorant practitioners treating this as wind-stroke and using dispersing agents would consume Middle Qi, leading to immediate decline and shortened life. At this moment, it is urgent to protect the postnatal aspect; if postnatal health is robust, congenital Qi can recover. The treatment principle should tonify both pre- and postnatal aspects. The formula used is Fuzi Gancao Tang (Aconite and Licorice Decoction), or with added Ginger, Cinnamon, Amomum Fruit, and Pinellia Tuber, taken slowly. Recovery is expected in over a month. Explanation of the formula is seen above.
The above dozens of articles specifically discuss Yang deficiency, pointing out the floating upward of congenital True Qi and repeatedly clarifying it. True Qi is the root of life and the spark of fire, stored in the Kidney, standing at the extreme of Water, serving as the root of Yin. Sinking and diving is favorable; floating upward is adverse. When disease reaches the point of floating True Qi, the Yang Qi of the five Zang and six Fu organs is exhausted, depleted, and reduced to the root. The Classics state: "All diseases of the five Zang eventually return to the Kidney," which is what this says. However, diseases of floating True Qi often resemble external-contracted Yang syndromes, leading people to overlook them. Careful investigation reveals that although the general image resembles external Yang syndromes, the manifestations are definitely Yin signs, with absolutely no substantial evidence of Yang syndromes. Scholars must pay attention here and not act rashly. Memorize the secrets for distinguishing Yang and Yin deficiency from the previous volume, and understand the explanations of Ministerial and Sovereign Fire. Then, Yang deficiency diseases in the upper, middle, and lower parts, and Yin deficiency diseases in the upper, middle, and lower parts, can all be treated according to the law. The formulas prepared in the Yang Deficiency chapter, including Jianzhong, Lizhong, Qianyang, Hu yang, Fengsui, and Jiang-Gui formulas, are all derived from Zhang Zhongjing's Sini Tang. Zhang Zhongjing stated: "For diseases of the Three Yang meridians, pathogens transform via Yang; when Yang is excessive, Yin must be deficient, so preserving Yin is essential." This is the origin of the theory of nourishing Yin and descending fire. "For diseases of the Three Yin meridians, pathogens enter and mostly transform via Yin; when Yin is excessive, Yang must decline, so restoring Yang is paramount." This is the origin of the theory of benefiting the source of fire to eliminate Yin shadows. Generally, in persons with Yang deficiency, Yin Qi naturally becomes excessive. When Yin Qi is excessive, it must ascend, presenting as toothache, gum swelling, mouth ulcers, tongue ulceration, dental bleeding, sore throat, and difficulty in urination or defecation. One must not recklessly apply methods of nourishing Yin and descending fire. Doing so aids Yin to extinguish Yang. Discrimination must be careful. Always seek the Yin signs, such as blue tongue, blue lips, and pale, spiritless complexion. Throughout history, confusion has prevailed, clarity is rare. Even intelligent and insightful individuals grasp only half and lose half. Although the golden needle is passed, it is as if not passed. Thus, few know Zhang Zhongjing's lifelong mental method. Here, dozens of articles are collected into one volume for future students to study. The subtle meaning of One Origin and the mechanisms of waxing and waning are clearly revealed. As for Zhang Zhongjing's main formulas for the Six Meridians, they possess fixed supreme principles. Modified and additive formulas are used according to the changes of pathogens. Formulas for the Three Yang follow ascending-dispersing, clearing, cooling, sweating, vomiting, and purging as standards. Formulas for the Three Yin focus on warming the middle, collecting, restoring Yang, descending rebellious Qi, and sealing/storing. The boundary between Yin and Yang is significantly distinct. Using Three Yang formulas to treat Three Yang diseases, even if mistaken, is not far off; using Three Yang formulas to treat Three Yin diseases is a great deviation. Those practicing this art must read many books and carefully ponder principles. Life and death hang in the balance. If this principle is not understood, one must never recklessly prescribe medicines. Earning a living is small; incurring guilt is large. Only through careful study and self-reflection without shame can one speak of medicine.
Chapter on Guest Doubts
A guest asked doubtfully: "Sir's discussion on Yang deficiency covers dozens of articles, all stating that these illnesses originate from the development of congenital Single Yang. Humans are ruled by the Heart, which is Fire and Yang. If it is said to be Yang deficiency, why not emphasize the Sovereign Fire in the upper part, but instead focus exclusively on the True Fire in the lower part?" I replied: "Great is this question! Do you not know that human life and destiny have roots and branches? What is the root? It is summarized in the phrase 'Heaven within Water.' Unfortunately, few in the world penetrate its depths, so I must analyze it. I have often said that Water and Fire rely on each other for movement (Water is Blood, Yin; Fire is Qi, Yang). Although they are two things, they are one mass, inseparable when divided, and unsurpassably united when combined. Taking a cup of boiling water as an analogy (Boiling refers to heat, i.e., the invisible True Fire within water), how can Qi ever leave Water, and how can Water ever leave Qi?"