人身五官百骸，有表里则有阴阳，有阴阳则有体用，以阳为体者则以阴为用，以阴为体者则以阳为用。此体用相资之道也。内而脏腑，莫不皆然。脏实而处内，以阴为体者也。腑虚而处外，以阳为用者也。如心与小肠为表里，心为之体则以小肠为心之用，而诸经之阴翳皆从小肠下泄，俾君主之官得以当阳而治。设无小肠以为之用，则乾清官内皆是阴翳障塞，而神明不能出矣。故治心病用心药，养其体也，佐以利小便药，通其用也。以小肠为体则以心为小肠之用，而诸经之阳光皆得从心健运，俾受盛之官得以宣布化物。设无心以为用，则君主失职，莫为支分派别，而化物无所出矣。故治小肠病用小肠药，疏其体也，佐以清心药，滋其用也。肺与大肠为表里，以肺为之体，则以大肠为之用，而水谷所腐之糟粕皆从大肠外出，俾相傅之官得以辅君出令。设无大肠以为之用，则清肃府中尽为浊气熏蒸，而治节不能出矣。故治肺病用肺药，从其体也，佐以大肠药泻其用也。以大肠为体则以肺为大肠之用，而水谷所化之精微皆从肺经四布，俾传导之官得以扫清污秽。设无肺以为之用，则升降无权，清浊混淆，而变化不能出矣。故治大肠病用大肠药，涤其体也，佐以肺药，助其用也。肝与胆为表里，肝为之体则以为胆为肝之用，俾躁急之性济以柔和，故卒然临之不惊，无故加之不怒。设无胆以为之用，则将军之官必失之一往直前而谋虑不能出矣。故治肝病用肝药，疏其体也，佐以胆药滋其用也。以胆为体则以肝为胆之用，俾畏葸之性助以刚果，故见义必为信道必笃。设无肝以为之用，则中正之官必失之委靡犹豫，而决断不能出矣。故治胆病用胆药，理其体也，佐以平肝药，达其用也，脾与胃为表里，以脾为体，则以胃为脾之用，俾主输之性必赖胃之充塞，乃得行其化长收藏。设无胃以为之用，则谏议之官未邀升斗之禄，何以施其膏泽乎故治脾病用脾药，治其体也，佐以胃药，治其用也。以胃为体，则以脾为胃之用，俾主纳之性必赖脾之运化，方得遂其清升浊降。设无脾以为之用，则仓廪之官必至水谷腐烂，将何以调其五味乎故治胃病用胃药，治其体也，佐以脾药，滋其用也。肾与膀胱为表里，以肾为体，则以膀胱为肾之用，而汪洋之水有所依归。设无膀胱以为之用，则作强之官终不能鉴龙门、穿碣石，旁开一路，以为之趋，而伎巧无所施矣。故肾病用肾药，治其体也，佐以膀胱药，泄其用也。以膀胱为体，则以肾为膀胱之用而清浊所归，能出能藏。设无肾以为之用，则州都之官非城门不闭，即管钥不开，而津液莫能藏，气化莫能出矣。故膀胱病用膀胱药，治其体也，佐以肾药，治其用也。
阴阳对待流行说
人身之阴阳，有对待，有流行。对待者，一而二也，流行者，二而一也。非对待无以立阴阳之用，非流行无以见阴阳之用。故人之心肾二也，气血二也，水火二也。上下各有其位，左右各循其途，两者相为对待依附而不可离也。然水中有火，火中有水，气以行血，血以行气。心根于肾，肾根于心，二者又无始无端互为其宅而不可分也。夫心肾，阴阳之根抵也。言心肾，而水火气血皆在其中矣。今但以心肾言之，心为离火而实火之主，肾为坎水而实水之源，故坎中之阳必升，升则阴随阳发，十土由兹而癖，八木由兹而茂，而两丁之火乃光焰烛天矣。离中之阴必降，则阳随阴敛，五土由是而阖，九金由是而凝，而壬癸之水乃滔滔不竭矣。即如四时之运行亦然。春夏阳之升也，而浓云骤雨，草木敷荣，非阴随阳发之征乎!秋冬阴降敛也，而万宝坚凝，冰霜凛冽，非阳随阴敛之象乎？然此阴阳升降，流行不息，偏不倚无过不及者，有中道焉。过则必至于亢害，不及复至于凝滞。在天地为时令之失正，在人身则寒热之偏陂。古之圣人与日月合其明，四时合其序者，体其道也。
阴阳刚柔论
《易》曰：立天之道曰阴与阳，立地之道曰柔与刚。天以气言，故曰阴阳也，地以质言，故曰柔刚。此天地之相为环应，并行而不相悖者也。故春夏阳之出也，阳出而地乃辟，辟则土膏动而万物敷荣。秋冬阴之入也，阴入而地乃阉，阖则坚冰至，万物敛藏。所以人身之应乎春夏者，神气舒展，体骨柔和，应乎秋冬者，精神爽健，体骨劲强，盖合乎天地阴阳刚柔也。苟当秋冬之令而不能闭藏，则来春无以为发生之机矣，焉得无病当春夏之令而不能发舒，则阳气内郁而不伸矣，又焉得无病经云：冬不藏精，春必病温。盖言闭藏者，不能闭藏也。又言；伤寒变热病，盖言发舒者不能发舒也。然则司命者，可不于天地之阴阳刚柔一参究乎?
人身坎水实根于离之真阴，故人不能节欲则肾水亏，肾水亏必至心阴亦亏，心阴亏则水失其主而无以镇阳光。由是火炎烁金而成咳嗽之症。且心生血者也，真阴亏而不能制火，则所生之血不随心阴下降，反随炎火上升之性，由吐咳而出矣。且心之真阴不特为肾水之根，而渚脏之阴皆根于此。此处一亏，则相火无不俱动，在肝则无水以滋木而火炽，在肺则无水以四布而金烁，在胃则无水以存津而土燥。诸脏亦无不有血，既为邪火煎熬，则津液之未化血者熏蒸而为痰涎，已化血者亦随火动而上逆妄行，此咳血吐血之所必至也。人身离火实根于坎之真阳，故人或思虑劳倦则离火不足，离火不足，必至肾阳亦不足，肾阳不足则火失其原而无以消阴翳，由是水泛土湿而成中满泻痢之证。且肾纳气者也，真阳亏而不能制水，则水谷所化之精气不得随坎阳上升，皆从顺下之性，随地道而去矣。且肾之真阳亦不特为离火之原，而诸经之阳悉原于此。此处一亏，则癸水尽足为患，在肝则无火以达之而木郁，在肺则无火以温之而金寒，在胃则无火以化之而土滞，诸经亦无不有气，一为阴寒凝涩，非至便闭中满而气不能通。即至下利不禁而气不能收，此又中满泄泻之所必至也。
虚火实火辨
当观人身之火，其患有二，感于外者火自外入，动于内者火自内生。外入者，六气时行之火由上而下者也，实火也，故其见证自经及腑，自腑入脏，初则发热咽痛，继则咳嗽呕吐，渐至饮食减少，大便或溏或秘，小便或数或涩。《内经》所谓因形伤气，从阳注阴者也。从阳注阴者，还从阳治，阳道常饶，宜清宜泻，忌补忌温，故仲景于三阳证治除麻桂发表之外，凡一切外火传入之证，皆用青龙、白虎、承气、猪苓等汤，始终以存阴为主。内生者，七情妄动之火由下而上者也，虚火也，故其见症自脏达腑，自腑达经，始而遗精便泄，继而饮食减少，渐至咳嗽，呕吐，发热咽痛，《内经》所谓因气伤形从阴注阳者也。从阴注阳者，还从阴治，阴道常亏，宜温宜补，忌泻忌清，故仲景于三阴证治除厥阴风火独盛之外，凡一切内火上越者，皆用真武、理中、白通、四逆等汤，始终以扶阴为主。虚实既判，治法迥殊。乃今之医者一见发热咳嗽等证，即是虚火，亦不知用甘润生津之品养阴退热，而专事寒凉，岂知寒凉久服，必至伤脾，脾伤则不能为胃行其津液，而布精于肺，肺虚则不能下生肾水而水亏，水亏而命门之火无制，反随少阴之络上克肺金。虚者固因虚，实者亦虚矣。当此之时，犹不知壮水导火之法，见其咳嗽声哑者，则用贝母、百合，咽痛口破者，则用元参、薄荷，发热不止者，则用黄芩、骨皮，气逆喘急者，则用苏子、橘红，小便短涩者，则用车前、泽泻。不辨其火之出自何经，传于何络，见症治症，以病试药，逮至木焚川竭，火烁金流，犹谓病实难医而不悔，叹惜哉!
人身先天无形之主气，所谓一太极也。至动而生阳，静而生阴，则一分而为二矣。动极而静，静极复动，循环变化而五气顺布，则五地见矣。故周子曰：五行一阴阳也，阴阳一太极也。然虽有太极阴阳五行之异名，而其实一，气之往来无间而已矣。人身太极，本之天地，受之父母，所谓天命之性，妙合于构精之始者也。至于胎育成形，先天已落后天之中矣。所以降生之初，有清浊厚薄之不同，则有生以后，亦遂有强弱寿夭之不齐。此皆非药石所能治，而其所可调养补益者，则惟后天之形质耳。至于先天，何由致力哉然先天者，后天之主宰也，后天者，先天之宅宇也。后天损坏而先天亦从之去矣，譬之屋宇损废而人犹能安其宅乎故培养后天，亦正所以防卫先天也。近代医书景岳谓两仪动静为五行之先天，先天者，性道也，五行寒热为两仪之苗，其先天乃上年之稻粒，今虽不见稻粒而稻粒之精神实寓于苗中。苗则在后天，后天者，变体也。冯氏又谓：右尺命门火之元阳生，右关脾土，脾土生，右寸肺金自下而生上，此先天之元气。至于火生土，土生金，金生水，复至自上而生下，此后天之元气。其说纷纷淆乱，难以为训。至先天属肾水，后天属脾土，其说似为近理，然此犹在后天中认识先天也，亦未为确论。余因特为是说以质高明，今试以物，譬之如今岁之后天之形质也。然稻粒犹有形者也，其稻粒之精神凝结于不见不闻者，乃其先天也，所谓上天之载无声无臭者是矣。
今夫火者，人身之充周而无间者也。故外而耳目之所以视听、手足之所以持行，内而五脏六腑之所以游溢精气而变化糟粕者，莫非火之运行之不息也。经曰：君火以明，相火以位，其义不昭然耶乃东垣云相火者，下焦包络之火，元气之贼也。丹溪述而证之，至景岳复起而辟之，谓轻清而光焰于上者，火之明也，重实而温于下者，火之位也。又云：邪念之火为邪气，君相之火为正气。正气之蓄为元气，凡火之贼伤人者，非君相之真火，皆邪火耳。邪火可言贼，相不可言贼。夫东垣、丹溪直将相火认错，固无足论，即景岳之说，亦属支离。其于经旨，君相之义均失之矣。余谓君火者，主也，明者，虚灵不昧之体。相火者，佐也，位者，靖共尔位之职。君授命于相，相奉命于君，故经云：心者君主之官，神明出焉。又云：主明则下安，以此养生则寿，主不明则十二官危，便道闭塞而不通，以此养生则夭。可见心为君主，故君火断属于心，而相火独归重于命者，以命门为火之所从出，诸经生化之本源也。君明则相良，故心无邪妄之私，相亦无邪妄之作。至于相火妄动，贼伤元气者，是犹权臣窃柄误国也。然其始亦由于君主之不明，而反为相火所役耳。譬之尧舜在上而水火工虞各有专司，自成无为之治，犹君火相火之助为理也。而相火之不可言贼也明矣。桀纣在上，廉来十五国，皆助虐之臣，以至身弑国亡，犹之君火不明而相火为害也。其不可以邪念之火为邪气，而君相之火为正气也亦明矣。故人身不可以无相火，犹君之不可无臣也。若以相火为邪火，臣其妄动而必使之安静无为，是犹豢养其臣而不授之以职，君亦何贵有是相乎人身亦不可专任相火，犹臣不可无君也。若即以相火为正气而任其妄动，以致心为形役，是犹欺君虐民之臣而无以制之，则相反足以贼其君耳。然则君火相火必如何而后可以相与有成也。意者，惟其有交泰之象乎。
经云：水火者，阴阳之征兆也。则是言阴阳者，莫过于水火矣。无如近代医书言水言火每分途而歧视之，而火阳根阴，水阴根阳，终莫之究。至赵养葵始以肾水属坎，指出真阳在坎水之中，为人身命脉之源，而独惜其以坎阴二爻，一属阴水，一属阳水，谓人身真阴亦即在是。更牵附六味、八味二方，强古人以就己之绳尺。呜呼！赵氏真阳之说，可谓发前人所未发，但既识真阳在坎水之中，而独不识真阴所在乎盖未观乎八卦河洛也。观八卦则坎之对待者离也，知坎中之有阳，则知离中之有阴矣。视河洛则一六水之对待者，二七火也。知六之有一则知七之有二矣，明此阴阳对待互根之理，则人身之肾水固真阳所寓，不可不保，岂离为真阴之所藏，而遂可忽视乎哉!盖真阳不亏，斯坎六之水不至泛滥瘀滞，犹江汉之潮汐，任呼吸之往来而不爽其期，真阴不亏，斯离七之火不至飞扬燥烈，犹灯烛之光照资膏油之涵养而长明。古人云：壮水之主，以镇阳光，补离中阴也。益火之源，以消阴翳，补坎中阳也。 外感内伤合河图生数成数说
人身有五官和全身骨骼，有了表里关系就有阴阳，有了阴阳就有体用关系。以阳作为本体，就以阴作为作用；以阴作为本体，就以阳作为作用。这是体与用相互资助的道理。内部而言，脏腑无不如此。脏气充实而位于内部，是以阴为本体的。腑气空虚而位于外部，是以阳为作用的。例如心与小肠互为表里，如果以心为本体，那么小肠就是心的作用，各种经络的阴浊之气都从小肠向下排泄，使得君主之官（心）能够处于阳位而治理全身。假如没有小肠来发挥它的作用，那么清明的官邸内就会充满阴浊之气阻塞，神明就无法显露了。所以治疗心病用心经的药物，是养护它的本体；辅以利小便的药物，是疏通它的作用。如果以小肠为本体，那么心就是小肠的作用，各种经络的阳光阳气都能随心气的健运而运行，使得受盛之官（小肠）能够宣布政令、消化食物。假如没有心来发挥它的作用，那么君主失职，无法进行分派管理，食物的转化就没有出路了。所以治疗小肠病用小肠经的药物，是疏理它的本体；辅以清心火的药物，是滋养它的作用。
肺与大肠互为表里，以肺为本体，那么大肠就是肺的作用，水谷消化后的糟粕都从大肠向外排出，使得相傅之官（肺）能够辅佐君主发布命令。假如没有大肠来发挥它的作用，那么清肃的府中就会被浊气熏蒸，治节功能就无法发挥了。所以治疗肺病用肺经的药物，是顺应它的本体；辅以大肠经的药物泻下，是通泄它的作用。如果以大肠为本体，那么肺就是大肠的作用，水谷转化而来的精微物质都通过肺经布散到全身，使得传导之官（大肠）能够扫清污秽。假如没有肺来发挥它的作用，那么升降功能就失去权力，清浊混淆，变化功能就无法产生了。所以治疗大肠病用大肠经的药物，是涤荡它的本体；辅以肺经的药物，是帮助它的作用。
肝与胆互为表里，肝为本体则胆为肝的作用，使得肝急躁的性格得到柔和的调节，所以面对突发情况不惊慌，无故受到侮辱不愤怒。假如没有胆来发挥它的作用，那么将军之官（肝）必然变得一往直前而缺乏谋略。所以治疗肝病用肝经的药物，是疏理它的本体；辅以胆经的药物，是滋养它的作用。如果以胆为本体，那么肝就是胆的作用，使得胆畏缩的性格得到刚毅果断的辅助，所以见到正义之事必定去做，信仰正道必定笃行。假如没有肝来发挥它的作用，那么中正之官（胆）必然变得萎靡犹豫，决断功能就无法产生了。所以治疗胆病用胆经的药物，是调理它的本体；辅以平肝的药物，是通达它的作用。
脾与胃互为表里，以脾为本体，那么胃就是脾的作用，使得主输注的特性必须依赖胃的充盈，才能执行化生、生长、收藏的功能。假如没有胃来发挥它的作用，那么谏议之官（脾）连一升一斗的俸禄都得不到，怎么能施展恩泽呢？所以治疗脾病用脾经的药物，是治疗它的本体；辅以胃经的药物，是治疗它的作用。如果以胃为本体，那么脾就是胃的作用，使得主受纳的特性必须依赖脾的运化，才能实现清气上升、浊气下降。假如没有脾来发挥它的作用，那么仓廪之官（胃）必然导致水谷腐烂，又怎能调和五味呢？所以治疗胃病用胃经的药物，是治疗它的本体；辅以脾经的药物，是滋养它的作用。
肾与膀胱互为表里，以肾为本体，那么膀胱就是肾的作用，汪洋之水有所依归。假如没有膀胱来发挥它的作用，那么作强之官（肾）终究不能像大禹凿龙门、穿碣石那样旁开一路，引导水流，技巧也就无处施展了。所以肾病用肾经的药物，是治疗它的本体；辅以膀胱经的药物，是泄导它的作用。如果以膀胱为本体，那么肾就是膀胱的作用，清浊之气有所归宿，能出能藏。假如没有肾来发挥它的作用，那么州都之官（膀胱）要么城门不闭，要么管钥不开，津液就无法储藏，气化功能就无法产生了。所以膀胱病用膀胱经的药物，是治疗它的本体；辅以肾经的药物，是治疗它的作用。
阴阳对待流行说
人身的阴阳，既有对待关系，又有流行关系。所谓对待，就是一分为二；所谓流行，就是合二为一。没有对待就无法确立阴阳的作用，没有流行就无法显现阴阳的作用。所以人心与肾是两个，气血是两个，水火是两个。上下各有其位置，左右各有其路径，两者相互对待依附而不能分离。然而水中含有火，火中含有水，气推动血，血推动气。心根源于肾，肾根源于心，两者又没有始无终，互为宅舍而不能分割。心肾是阴阳的根本。说到心肾，水火气血都在其中了。现在仅以心肾来说，心属离火，是实火的主宰；肾属坎水，是实水的源头。所以坎水中的阳气必然上升，上升则阴随阳发，十土由此滋生，八木由此茂盛，两丁之火便光焰烛天。离水中的阴气必然下降，则阳随阴敛，五土由此闭合，九金由此凝结，壬癸之水便滔滔不绝。就像四季的运行也是如此。春夏季节阳气上升，浓云骤雨，草木繁荣，这不是阴随阳发的征兆吗！秋冬季节阴气下降收敛，万物坚固凝聚，冰霜凛冽，这不是阳随阴敛的景象吗？然而这种阴阳升降，流行不息，偏斜不倚、无过无不及的状态，是有中道存在的。过度则必然导致亢盛危害，不足则又导致凝滞。在天地表现为时令失正，在人身体现为寒热偏颇。古代的圣人与日月同其光明，与四时同其秩序，是体悟了这条大道。
阴阳刚柔论
《易经》说：确立天的道理叫阴与阳，确立地的道理叫柔与刚。天以气来说，所以叫阴阳；地以质来说，所以叫柔刚。这是天地相互呼应，并行而不违背的道理。所以春夏季节阳气外出，阳气外出大地才开辟，开辟则土壤松动而万物繁荣。秋冬季节阴气入内，阴气入内大地才闭合，闭合则坚冰到来，万物收敛储藏。所以人身应合春夏的时候，神气舒展，体骨柔和；应合秋冬的时候，精神爽健，体骨劲强，这是合乎天地的阴阳刚柔。如果在秋冬当令时不能闭藏，那么来年春天就没有发生的机枢了，怎么会不得病呢？如果在春夏当令时不能发舒，那么阳气就会内郁而不能伸展，又怎么会不得病呢？《内经》说：冬天不藏精，春天必患温病。这是说闭藏者，不能做到闭藏。又说：伤寒变为热病，这是说发舒者不能做到发舒。既然如此，掌管生命的人，能不研究天地的阴阳刚柔吗？
人身的坎水实际上根源于离的真阴，所以人如果不能节制欲望，肾水就会亏损，肾水亏损必然导致心阴也亏损，心阴亏损则水失去主宰而无法镇摄阳光。因此火炎灼烧肺金而成咳嗽的症状。而且心是生成血的器官，真阴亏损不能制火，那么所生的血就不能随心阴下降，反而随着炎火上升的性质，通过呕吐和咳嗽而出血了。而且心的真阴不仅是肾水的根源，五脏的阴也都根源于此。这里一旦亏损，相火没有不一起动的，在肝则无水滋润木而火炽盛，在肺则无水布散而金被灼伤，在胃则无水存留津液而土干燥。各脏也都有血，既然被邪火煎熬，那么未化为血的津液被熏蒸成为痰涎，已化为血的也随着火势上逆妄行，这是咳血吐血必然导致的结果。人身的离火实际上根源于坎的真阳，所以人如果思虑劳倦，离火就会不足，离火不足必然导致肾阳也不足，肾阳不足则火失去本源而无法消除阴翳，因此水泛土湿而成中满、泻痢的症状。而且肾是纳气的器官，真阳亏损不能制水，那么水谷转化的精气就不能随坎阳上升，都顺着下行的性质，随地道而流失了。而且肾的真阳不仅只是离火的源头，各经的阳气都源于此。这里一旦亏损，癸水尽足为患，在肝则无火通达而木郁结，在肺则无火温煦而金寒冷，在胃则无火腐熟而土停滞。各经也都有气，一旦被阴寒凝涩，不是到大便秘结、中满而气不能通，就是到下利不禁而气不能收，这又是中满泄泻必然导致的结果。
虚火实火辨
观察人身的火，其病患有两种，感于外部的火是从外而入，动于内部的火是从内而生。外入的火，是六气时行之火从上而下，属于实火，所以其见证从经络传到腑，从腑传入脏，起初发热咽痛，接着咳嗽呕吐，逐渐饮食减少，大便或溏或秘，小便或频或涩。《内经》所说的因形伤气，从阳注入阴。从阳注入阴的，还要从阳治疗，阳道常有余，宜清宜泻，忌补忌温，所以张仲景在三阳证的治疗中，除了麻黄汤、桂枝汤发表之外，凡是一切外火传入的证候，都用青龙汤、白虎汤、承气汤、猪苓汤等方剂，始终以保存阴液为主。内生的火，是七情妄动之火从下而上，属于虚火，所以其见证从内脏达于腑，从腑达于经络，开始遗精便泄，接着饮食减少，逐渐咳嗽，呕吐，发热咽痛，《内经》所说的因气伤形，从阴注入阳。从阴注入阳的，还要从阴治疗，阴道常亏虚，宜温宜补，忌泻忌清，所以张仲景在三阴证的治疗中，除了厥阴风火独盛的情况外，凡是一切内火上越的，都用真武汤、理中汤、白通汤、四逆汤等方剂，始终以扶持阴液为主。虚实既然判断清楚，治法截然不同。然而现在的医生一见发热咳嗽等证，就认为是虚火，也不知道用甘润生津的药物养阴退热，而专门使用寒凉药，岂不知寒凉药久服，必然损伤脾胃，脾伤则不能为胃输送津液，并布散精微于肺，肺虚则不能下行滋生肾水而水亏，水亏而命门之火失去制约，反而随着少阴的络脉上行克制肺金。虚的固然因为虚，实的也变得虚了。在这个时候，还不知道壮水制火的方法，见到咳嗽声哑的，就用贝母、百合，咽痛口破的，就用元参、薄荷，发热不止的，就用黄芩、地骨皮，气逆喘急的，就用苏子、橘红，小便短涩的，就用车前子、泽泻。不辨别火出自哪条经络，传于哪条络脉，见症治症，拿病人试药，等到木焚川竭，火烁金流，还认为病实在难治而不后悔，可叹啊！
人身的先天无形之主气，所谓的太极。到了动而生阳，静而生阴，就一分而为二了。动到极致转为静，静到极致复转为动，循环变化而五行之气顺布，五地就显现了。所以周敦颐说：五行即是一阴阳，阴阳即是太极。虽然以太极、阴阳、五行为异名，但其实是一样的，只是气的往来不间断罢了。人身的太极，本源于天地，禀受于父母，所谓天命之性，在受精成形之初就妙合在一起了。至于胎育成形，先天就已经落在后天的中了。所以降生之初，有清浊厚薄的不同，那么有生以后，也就有强弱寿夭的不齐。这些都不是药石所能治疗的，而可以调养补益的，只有后天的形质罢了。至于先天，从哪里致力呢？然而先天是后天主宰，后天是先天宅宇。后天损坏而先天也随之离去，譬如屋宇损废而人还能安住其宅吗？所以培养后天，正是为了防卫先天。近代医书张景岳说两仪动静是五行的先天，先天是性道，五行寒热是两仪的苗，其先天是去年的稻粒，现在虽不见稻粒而稻粒的精神实在寓于苗中。苗是在后天，后天是变体。冯氏又说：右尺命门火之元阳生，右关脾土，脾土生，右寸肺金自下而生上，这是先天元气。至于火生土，土生金，金生水，复至自上而生下，这是后天元气。他的说法纷纷淆乱，难以作为准则。至于先天属肾水，后天属脾土，这种说法似乎近于合理，但这还是在后天中认识先天，也不算确论。我因此特意提出这个说法来向高明请教，现在试着用物比喻，比如今年的后天形质。然而稻粒还是有形的，那稻粒的精神凝结于看不见听不到的地方，才是先天，所谓上天之载无声无臭就是这样。
如今火，是人身上充周而无间隙的。所以外在耳目之所以视听、手足之所以持行，内在五脏六腑之所以游溢精气而变化糟粕，无非是火的运行不息。经文说：君火以明，相火以位，意义不是很明显吗？然而李东垣说相火是下焦包络之火，是元气的贼害。朱丹溪阐述并证明这一点，直到张景岳起来驳斥他，说轻清而光焰于上的，是火的明；重实而温于下的，是火的位置。又说：邪念之火为邪气，君相之火为正气。正气的蓄积为元气，凡是贼害伤人的火，不是君相的真火，都是邪火罢了。邪火可以说贼，相火不能说贼。李东垣、朱丹溪直接将相火认错，本来不值得讨论，即使张景岳的说法，也属于支离破碎。对于经文旨意，君相的含义都失之毫厘了。我认为君火是主，明者是虚灵不昧的本体。相火是佐，位者是靖共尔位的职责。君授予命令给相，相奉行命令于君，所以经文说：心是君主之官，神明由此发出。又说：主明则下安，以此养生则长寿，主不明则十二官危险，道路闭塞不通，以此养生则夭折。可见心为君主，所以君火断然归属于心，而相火独归于命门，因为命门是火所从出的地方，是诸经生化之本源。君明则相良，所以心无邪妄之私，相也没有邪妄之作。至于相火妄动，贼害伤元气，这犹如权臣窃据权柄误国。然而其开始也由于君主的不明，反而被相火役使。譬如尧舜在上，水火工虞各有专司，自然成就无为而治，犹如君火相火相助为理。而相火不可称为贼是很明显的。桀纣在上，廉来十五国，都是助虐之臣，以至于身死国亡，犹如君火不明而相火为害。其不可以将邪念之火视为邪气，而将君相之火视为正气也是很明显的。所以人身不可以没有相火，犹如君主不可以没有臣子。如果把相火当作邪火，臣子妄动而一定要使其安静无为，这犹如豢养臣子却不授予职务，君主又何必有这个宰相呢？人身也不可专任相火，犹如臣子不可以没有君主。如果直接把相火当作正气而任由其妄动，以致心被形体役使，这犹如欺君虐民的臣子而没有加以制约，则相反足以贼害君主。那么君火相火必须怎样之后才可以相辅相成呢？我想，大概只有具有交泰之象吧。
经文说：水火是阴阳的征兆。那么谈论阴阳，莫过于水火了。无奈近代医书谈论水谈论火往往分途而歧视它们，而火阳根于阴，水阴根于阳，最终没有探究清楚。直到赵养葵才开始以肾水属坎，指出真阳在坎水之中，为人身命脉之源，但可惜他将坎卦的二爻，一属阴水，一属阳水，认为人身真阴也在此处。更牵强附会六味地黄丸、八味丸两个方剂，强行让古人符合自己的标准。唉！赵氏关于真阳的说法，可以说是发掘前人所未发现的，但既然认识到真阳在坎水之中，却唯独不认识真阴在哪里呢？大概是没有观察八卦河图洛书吧。观察八卦则坎的对待者是离，知道坎中有阳，就知道离中有阴了。视河洛则一六水的对待者是二七火。知道六中有一就知道七中有二了，明白这阴阳对待互根的道理，那么人身的肾水固然是真阳所寓居，不可不保养，难道离卦是真阴所藏，就可以忽视吗！真阳不亏损，那么坎六之水不至于泛滥瘀滞，犹如江汉潮汐，任凭呼吸往来而不差其期；真阴不亏损，那么离七之火不至于飞扬燥烈，犹如灯烛之光依靠膏油涵养而长明。古人说：壮水之主，以镇阳光，是补离中阴。益火之源，以消阴翳，是补坎中阳。 外感内伤合河图生数成数说
The human body has five sense organs and all bones. With exterior-interior relationships, there is Yin and Yang; with Yin and Yang, there is Ti (Substance) and Yong (Function). When Yang serves as the Ti, Yin serves as the Yong; when Yin serves as the Ti, Yang serves as the Yong. This is the way in which Ti and Yong mutually support each other. Internally, this applies to all Zang (Solid) and Fu (Hollow) organs. The Zang organs are full and located internally, thus taking Yin as their Ti. The Fu organs are hollow and located externally, thus taking Yang as their Yong. For example, the Heart and Small Intestine are exterior-interior pairs. If the Heart is taken as the Ti, then the Small Intestine is the Yong of the Heart, and the Yin turbidity of all meridians drains downward through the Small Intestine, allowing the Ruler Organ (Heart) to occupy the Yang position and govern the whole body. If there were no Small Intestine to perform its function, the clear palace would be blocked by Yin turbidity, and the Shen (Spirit) could not emerge. Therefore, treating Heart diseases uses Heart meridian herbs to nourish its Ti, assisted by diuretic herbs to unblock its Yong. If the Small Intestine is taken as the Ti, then the Heart is the Yong of the Small Intestine, and the Yang sunlight of all meridians can circulate freely with the vigorous movement of Heart Qi, allowing the Receiving Organ (Small Intestine) to promulgate directives and transform food. If there were no Heart to perform its function, the Ruler would lose his duty, unable to distribute and categorize, and the transformation of food would have no outlet. Therefore, treating Small Intestine diseases uses Small Intestine meridian herbs to regulate its Ti, assisted by Heart-clearing herbs to nourish its Yong.
The Lung and Large Intestine are exterior-interior pairs. If the Lung is taken as the Ti, then the Large Intestine is the Yong of the Lung, and the dregs of digested food and water exit outward through the Large Intestine, allowing the Assistant Organ (Lung) to assist the Ruler in issuing commands. If there were no Large Intestine to perform its function, the clear and肃 (solemn) fu would be steamed by turbid Qi, and the regulation function could not emerge. Therefore, treating Lung diseases uses Lung meridian herbs to follow its Ti, assisted by Large Intestine meridian herbs to purge its Yong. If the Large Intestine is taken as the Ti, then the Lung is the Yong of the Large Intestine, and the essence refined from food and water spreads throughout the body via the Lung meridian, allowing the Conduction Organ (Large Intestine) to sweep away filth. If there were no Lung to perform its function, the ascending and descending functions would lose authority, clarity and turbidity would mix, and transformation could not occur. Therefore, treating Large Intestine diseases uses Large Intestine meridian herbs to cleanse its Ti, assisted by Lung meridian herbs to aid its Yong.
The Liver and Gallbladder are exterior-interior pairs. If the Liver is the Ti, then the Gallbladder is the Yong of the Liver, tempering the Liver's irritable nature with gentleness, so that one does not panic when confronted suddenly nor anger when insulted without cause. If there were no Gallbladder to perform its function, the General Organ (Liver) would inevitably charge forward blindly without strategy. Therefore, treating Liver diseases uses Liver meridian herbs to regulate its Ti, assisted by Gallbladder meridian herbs to nourish its Yong. If the Gallbladder is taken as the Ti, then the Liver is the Yong of the Gallbladder, assisting the Gallbladder's timid nature with courage and decisiveness, so that one acts righteously and adheres firmly to the Dao. If there were no Liver to perform its function, the Justice Organ (Gallbladder) would become listless and hesitant, and decision-making could not emerge. Therefore, treating Gallbladder diseases uses Gallbladder meridian herbs to regulate its Ti, assisted by Liver-calming herbs to facilitate its Yong.
The Spleen and Stomach are exterior-interior pairs. If the Spleen is the Ti, then the Stomach is the Yong of the Spleen, such that the Spleen's transportive nature relies on the Stomach's fullness to execute transformation, growth, and storage. If there were no Stomach to perform its function, the Remonstrance Organ (Spleen) would receive no salary, how could it dispense grace? Therefore, treating Spleen diseases uses Spleen meridian herbs to treat its Ti, assisted by Stomach meridian herbs to treat its Yong. If the Stomach is taken as the Ti, then the Spleen is the Yong of the Stomach, such that the Stomach's receiving nature relies on the Spleen's transformation to achieve the ascending of clear Qi and descending of turbid Qi. If there were no Spleen to perform its function, the Granary Organ (Stomach) would lead to the rotting of food and drink, how could it harmonize the five flavors? Therefore, treating Stomach diseases uses Stomach meridian herbs to treat its Ti, assisted by Spleen meridian herbs to nourish its Yong.
The Kidney and Bladder are exterior-interior pairs. If the Kidney is the Ti, then the Bladder is the Yong of the Kidney, providing a destination for vast waters. If there were no Bladder to perform its function, the Strong Organ (Kidney) could not carve paths like Yu the Great at Longmen and Jieshi, guiding the flow, and skills would have nowhere to apply. Therefore, treating Kidney diseases uses Kidney meridian herbs to treat its Ti, assisted by Bladder meridian herbs to drain its Yong. If the Bladder is taken as the Ti, then the Kidney is the Yong of the Bladder, where clear and turbid Qi find their归宿 (destination), able to exit and store. If there were no Kidney to perform its function, the Capital Organ (Bladder) would either fail to close its gates or fail to open its locks, and Jin Ye (Body Fluids) could not be stored, and Qi transformation could not emerge. Therefore, treating Bladder diseases uses Bladder meridian herbs to treat its Ti, assisted by Kidney meridian herbs to treat its Yong.
Theory of Yin-Yang Opposition and Circulation
Human Yin and Yang have both oppositional (Duidai) and circulating (Liuxing) aspects. Opposition means one becomes two; circulation means two become one. Without opposition, the function of Yin and Yang cannot be established; without circulation, the function of Yin and Yang cannot be manifested. Thus, the Heart and Kidney are two, Qi and Blood are two, Water and Fire are two. They have their respective positions above and below, and their respective paths left and right, mutually opposing and relying on each other inseparably. Yet Fire exists within Water, and Water exists within Fire; Qi moves Blood, and Blood moves Qi. The Heart roots in the Kidney, and the Kidney roots in the Heart; they have no beginning or end, mutually serving as dwellings, inseparable. The Heart and Kidney are the root of Yin and Yang. Speaking of Heart and Kidney encompasses Water, Fire, Qi, and Blood. Taking only Heart and Kidney as examples: the Heart belongs to Li Fire and is the master of actual Fire; the Kidney belongs to Kan Water and is the source of actual Water. Thus, the Yang within Kan must ascend; upon ascending, Yin follows Yang, causing Earth to proliferate and Wood to flourish, making the Fire of Ding blaze to the sky. The Yin within Li must descend; upon descending, Yang condenses with Yin, causing Earth to close and Metal to consolidate, making the Water of Ren and Gui flow endlessly. This is also true of the four seasons. In Spring and Summer, Yang ascends, bringing clouds, rain, and flourishing vegetation; is this not the sign of Yin following Yang? In Autumn and Winter, Yin descends and condenses, bringing hardening of harvests and biting frost; is this not the image of Yang condensing with Yin? However, in this ceaseless circulation of Yin and Yang ascent and descent, there is a Mean (Zhongdao) where there is no bias, excess, or deficiency. Excess leads to hyperactivity and harm; deficiency leads to stagnation. In Heaven and Earth, this manifests as失常 (abnormal) seasons; in the human body, it manifests as biased Cold and Heat. Ancient sages aligned their brightness with the sun and moon and their order with the four seasons, embodying this Dao.
Theory of Yin-Yang and Rigidity-Plasticity
The I Ching says: The Way of Heaven is called Yin and Yang; the Way of Earth is called Plasticity and Rigidity. Heaven speaks of Qi, hence Yin and Yang; Earth speaks of Substance, hence Plasticity and Rigidity. This is the mutual response of Heaven and Earth, running parallel without contradiction. Thus, in Spring and Summer, Yang emerges, opening the Earth, loosening the soil, and causing all things to flourish. In Autumn and Winter, Yin enters, closing the Earth, bringing hard ice, and causing all things to hide. Accordingly, when the human body responds to Spring and Summer, Shen Qi is舒展 (relaxed) and bones/flesh are plastic; when responding to Autumn and Winter, Jing Shen is crisp and strong, and bones/flesh are rigid. This aligns with the Heaven and Earth's Yin-Yang and Rigidity-Plasticity. If one cannot hide and store during the Autumn/Winter command, there will be no mechanism for generation in the coming Spring, leading to disease. If one cannot expand and release during the Spring/Summer command, Yang Qi will be internally depressed and unable to extend, leading to disease. The Classic says: "If one does not store Essence in Winter, one will suffer from Warm diseases in Spring." This refers to those who cannot hide/store. It also says: "Cold damage transforms into heat diseases," referring to those who cannot expand/release. Therefore, those responsible for life must investigate the Yin-Yang and Rigidity-Plasticity of Heaven and Earth.
Theory of Heart-Kidney Pathogenesis
Kan Water actually roots in the True Yin of Li. Thus, if one cannot restrain desires, Kidney Water declines; if Kidney Water declines, Heart Yin inevitably declines; if Heart Yin declines, Water loses its master and cannot suppress Yang Light. Consequently, Fire flares, scorching Metal, resulting in cough. Moreover, the Heart generates Blood. If True Yin declines and cannot control Fire, the generated Blood cannot descend with Heart Yin but instead rises with the flaming nature of Fire, exiting through vomiting and coughing. Furthermore, the Heart's True Yin is not only the root of Kidney Water but also the root of Yin in all Zang organs. If this declines, Ministerial Fire will inevitably move together. In the Liver, there is no Water to nourish Wood, so Fire blazes; in the Lung, there is no Water to spread, so Metal scorches; in the Stomach, there is no Water to preserve Jin Ye, so Earth dries. All Zang organs have Blood; once simmered by evil Fire, untransformed Jin Ye steams into Phlegm-Saliva, and transformed Blood reverses upward recklessly due to Fire. This inevitably leads to hemoptysis and hematemesis.
Li Fire actually roots in the True Yang of Kan. Thus, if one suffers from mental worry and fatigue, Li Fire becomes insufficient; if Li Fire is insufficient, Kidney Yang inevitably becomes insufficient; if Kidney Yang is insufficient, Fire loses its source and cannot dissipate Yin Shadows. Consequently, Water floods and Earth dampens, resulting in abdominal fullness and dysentery/diarrhea. Moreover, the Kidney grasps Qi. If True Yang declines and cannot control Water, the essence refined from food and water cannot ascend with Kan Yang but flows downward with the nature of Earth, leaving the body. Furthermore, the Kidney's True Yang is not only the source of Li Fire but also the origin of Yang in all meridians. If this declines, Gui Water becomes a disaster. In the Liver, there is no Fire to reach it, so Wood stagnates; in the Lung, there is no Fire to warm it, so Metal becomes cold; in the Stomach, there is no Fire to transform it, so Earth stagnates. All meridians have Qi; once congealed by Yin-Cold, it either leads to constipation and abdominal fullness with blocked Qi, or to uncontrollable diarrhea with unrestrained Qi. This inevitably leads to abdominal fullness and diarrhea.
Differentiation of Deficient and Excess Fire
Observing Fire in the human body, there are two types of pathology: Fire entering from outside, and Fire arising from inside. External fire comes from the Six Qi seasonal pathogens, moving downward from above; it is Excess Fire. Its manifestations progress from meridians to Fu organs, and from Fu to Zang organs. Initially fever and sore throat, followed by cough and vomiting, gradually reduced appetite, loose or constipated stool, frequent or difficult urination. As stated in the Neijing: "Injury to form damages Qi, flowing from Yang into Yin." To treat flowing from Yang into Yin, one treats from Yang. The Yang path is often abundant; one should clear and purge, avoiding tonification and warming. Thus, Zhang Zhongjing, in treating Yang syndrome, besides Ma Huang Tang and Gui Zhi Tang for releasing the exterior, uses Qing Long Tang, Bai Hu Tang, Cheng Qi Tang, and Zhu Ling Tang for all external fire transmissions, always prioritizing preserving Yin.
Internal fire arises from the Seven Emotions moving recklessly, rising upward from below; it is Deficient Fire. Its manifestations progress from Zang to Fu, and from Fu to meridians. Initially seminal emission and loose stools, followed by reduced appetite, gradually cough, vomiting, fever, and sore throat. As stated in the Neijing: "Injury to Qi damages form, flowing from Yin into Yang." To treat flowing from Yin into Yang, one treats from Yin. The Yin path is often deficient; one should warm and tonify, avoiding purging and clearing. Thus, Zhang Zhongjing, in treating Yin syndrome, except for Jue Yin wind-fire dominance, uses Zhen Wu Tang, Li Zhong Tang, Bai Tong Tang, and Si Ni Tang for all internal fire surging upward, always prioritizing supporting Yin. Once deficiency and excess are distinguished, treatment methods differ vastly. However, modern physicians see fever and cough and assume Deficient Fire, failing to use sweet-moistening herbs to nourish Yin and reduce heat, instead using cold herbs exclusively. Who knows that long-term use of cold herbs damages the Spleen; if the Spleen is damaged, it cannot transport Jin Ye for the Stomach and distribute essence to the Lung; if the Lung is deficient, it cannot generate Kidney Water downward, leading to Water deficiency; if Water is deficient, Ming Men Fire is uncontrolled, ascending via the Shaoyin channel to attack Lung Metal. What was deficient remains deficient; what was excess becomes deficient. At this time, not knowing the method of strengthening Water to guide Fire, seeing hoarse cough, they use Bei Mu and Bai He; seeing sore throat and mouth ulcers, they use Yuan Shen and Bo He; seeing persistent fever, they use Huang Qin and Gu Pi; seeing rebellious Qi and wheezing, they use Su Zi and Ju Hong; seeing scanty dark urine, they use Che Qian and Ze Xie. Not distinguishing which meridian the fire originates from or which collateral it transmits through, treating symptoms with symptoms, testing medicine on patients, until Wood burns and Rivers dry, Fire scorches and Metal melts, they still claim the disease is incurable without regret. Alas!
Theory of Innate and Acquired
The innate invisible Master Qi of the human body is what is called the Taiji. Upon movement, Yang is born; upon stillness, Yin is born; thus, one divides into two. Movement extreme turns to stillness; stillness extreme turns to movement; cycling and changing, the Five Qi distribute smoothly, and the Five Earths appear. Thus, Zhou Dunyi said: "Five Elements are one Yin-Yang; Yin-Yang is one Taiji." Although named differently as Taiji, Yin-Yang, and Five Elements, they are essentially one, merely the uninterrupted coming and going of Qi. Human Taiji originates from Heaven and Earth, received from parents, the Nature bestowed by Heaven, perfectly combined at conception. Upon fetal formation, Innate falls within Acquired. Thus, at birth, there are differences in clarity/turbidity and thickness/thinness, leading to inequalities in strength and longevity after birth. These cannot be treated by medicine, but what can be nourished and supplemented is only the Acquired substance. How can effort be made regarding the Innate? However, Innate is the master of Acquired; Acquired is the dwelling of Innate. If Acquired is damaged, Innate departs with it. Can a person live comfortably in a ruined house? Thus, cultivating Acquired is precisely defending Innate. Modern physician Zhang Jingyue said the dynamic/static of Liang Yi is the Innate of Five Elements; Innate is Nature/Dao; the cold/heat of Five Elements are the sprouts of Liang Yi; its Innate is last year's rice grain. Though the grain is unseen, its spirit resides in the sprout. The sprout is in Acquired; Acquired is the transformed body. Feng Shi said: Yuan Yang of Ming Men Fire at Right Chi generates, Spleen Earth at Right Guan generates, Lung Metal at Right Cun generates upward from below; this is Innate Yuan Qi. Then Fire generates Earth, Earth generates Metal, Metal generates Water, generating downward from above; this is Acquired Yuan Qi. His theories are chaotic and confusing, unfit for instruction. The theory that Innate belongs to Kidney Water and Acquired to Spleen Earth seems reasonable, but this is still recognizing Innate within Acquired, not a definitive conclusion. I propose this theory for discussion. Using an object as analogy: this year's Acquired substance. Rice grains are still有形 (form); the spirit condensed in the unseen/unheard is Innate, as described: "The workings of Heaven are soundless and odorless."
Theory of Sovereign and Ministerial Fire
Fire fills the human body without gap. Externally, eyes/ears see/hear, hands/feet hold/walk; internally, Zang/Fu organs circulate essence and transform dregs—all are the ceaseless operation of Fire. The Classic says: "Sovereign Fire illuminates, Ministerial Fire occupies its position." Is this not clear? However, Li Dongyuan said Ministerial Fire is the Fire of the Lower Jiao Bao Luo, a thief of Yuan Qi. Zhu Danxi elaborated and proved this. Later, Zhang Jingyue refuted it, saying: Light/clear and blazing above is Fire's illumination; heavy/solid and warming below is Fire's position. He added: Fire of evil thoughts is Evil Qi; Sovereign/Ministerial Fire is Correct Qi. Accumulated Correct Qi is Yuan Qi. Any fire harming people is not True Sovereign/Ministerial Fire, but Evil Fire. Evil Fire can be called a thief; Ministerial Fire cannot. Li Dongyuan and Zhu Danxi mistook Ministerial Fire, which is hardly worth discussing. Even Zhang Jingyue's view is fragmented, losing the meaning of Sovereign and Ministerial in the Classic. I believe Sovereign Fire is the Master; Illumination is the void, spiritual, unclouded substance. Ministerial Fire is the Assistant; Position is the duty of diligent service. The Master gives orders to the Assistant; the Assistant obeys the Master. Thus, the Classic says: "The Heart is the Sovereign Organ, from which Shen Ming emerges." And: "If the Master is clear, the subordinates are peaceful; using this for health brings longevity. If the Master is unclear, the Twelve Organs are in danger, pathways block, using this for health brings early death." Clearly, the Heart is the Sovereign, so Sovereign Fire belongs to the Heart. Ministerial Fire returns to Ming Men, as Ming Men is where Fire originates, the source of transformation for all meridians. If the Master is clear, the Assistant is good; thus, the Heart has no evil selfishness, and the Assistant has no evil actions. When Ministerial Fire moves recklessly, harming Yuan Qi, it is like a powerful minister usurping power and ruining the state. But it starts because the Master is unclear, being enslaved by Ministerial Fire. Like Yao and Shun above, with officials managing water, fire, works, and woods, achieving non-action governance, just as Sovereign and Ministerial Fire assist in order. Thus, Ministerial Fire cannot be called a thief. Like Jie and Zhou above, corrupt ministers aiding tyranny, leading to death and ruin, just as Unclear Sovereign Fire causes Ministerial Fire harm. It is clear that Evil Thoughts' Fire is Evil Qi, while Sovereign/Ministerial Fire is Correct Qi. Thus, the human body cannot lack Ministerial Fire, just as a ruler cannot lack ministers. If Ministerial Fire is seen as Evil Fire, and ministers are kept quiet without duties, why have a prime minister? The body cannot rely solely on Ministerial Fire, just as ministers cannot lack a ruler. If Ministerial Fire is Correct Qi and allowed to move recklessly, enslaving the Heart, it is like tyrannical ministers unchecked, harming the ruler. So how can Sovereign and Ministerial Fire succeed together? Perhaps only through the image of Jiao Tai (Mutual Interaction).
Theory of True Yin and True Yang
The Classic says: "Water and Fire are the omens of Yin and Yang." Thus, speaking of Yin and Yang, none surpass Water and Fire. Unfortunately, modern medical books discuss Water and Fire separately and discriminately, never investigating that Fire/Yang roots in Yin, and Water/Yin roots in Yang. Zhao Yangkui started by assigning Kidney Water to Kan, pointing out True Yang is within Kan Water, the source of life. But he mistakenly assigned Kan's two lines to Yin Water and Yang Water, claiming True Yin is also there. He forced ancient texts to fit his standards using Liu Wei Di Huang Wan and Ba Wei Di Huang Wan. Alas! Zhao's theory of True Yang uncovered the unknown, but since he recognized True Yang in Kan Water, why did he miss True Yin? He hadn't observed the Bagua and Hetu/Luoshu. Observing Bagua, Kan's opposite is Li. Knowing Yang in Kan, one knows Yin in Li. Viewing Hetu/Luoshu, One/Six Water opposes Two/Seven Fire. Knowing One in Six, one knows Two in Seven. Understanding this principle of Yin-Yang opposition and mutual rooting, Kidney Water houses True Yang and must be protected. Can Li, housing True Yin, be ignored? If True Yang is not deficient, Kan Six Water does not flood or stagnate, like Jianghan tides, matching breath cycles perfectly. If True Yin is not deficient, Li Seven Fire does not fly wildly or burn dryly, like lamp light sustained by oil, shining forever. Ancients said: "Strengthen the master of Water to suppress Yang Light" is supplementing Li's Yin. "Benefit the source of Fire to dissipate Yin Shadows" is supplementing Kan's Yang. External/Internal Damage combined with Hetu Generation/Completion Numbers Theory