《阴阳应象大论》曰∶阴阳者，天地之道也（太极动而生阳，静而生阴，天主于动，地主于静。《易》
曰∶一阴一阳之谓道。阴阳者，本道体以生，道者，由阴阳而显），万物之纲纪（总之为纲，大德敦化也；纷
之为纪，小德川流也），变化之父母（经曰∶物生谓之化，物极谓之变。《易》曰∶在天成象，在地成形，变
化见矣。朱子曰∶变者化之渐，化者变之成。阴可变为阳，阳可变为阴，然变化虽多，靡不统于阴阳，故为父
母），生杀之本始（阴阳交则物生，阴阳隔则物死，阳来则物生，阴至则物死，万物之生杀。莫不以阴阳为本
始也），神明之府也（变化不测之谓神，品物流形之谓明。府者，言变化流形，皆从此出也）。治病必求于本
（人之疾病，虽非一端，然而或属虚，或属实，或属寒，或属热，或在气，或在血，或在脏，或在腑，皆不外于
阴阳，故知病变无穷，而阴阳为之本。经曰知其要者，一言而终是也。但明虚实，便别阴阳，然疑似之间大难
剖别。如至虚有盛候，反泻衔冤；大实
有羸状，误补益疾；阴症似阳，清之者必败；阳症似阴，温之者必亡。气主煦之，血主濡之，气药有生血之功，
血药无益气之理。病在腑而误攻其脏，谓之引贼入门；病在脏而误攻其腑，譬之隔靴搔痒。洞察阴阳，直穷病
本，庶堪司命。若疑似之际，混而弗明，攻补之间，畏而弗敢，实实虚虚之祸尚忍言哉）。
故积阳为天，积阴为地。阴静阳躁（积者，汇萃之称也。合一切之属于阳者，莫不本乎天；合一切之
属于阴者，莫不本乎地。阴主静，阳主躁，其性然也），阳生阴长，阳杀阴藏（阳之和者为发育，阴之和者为成
实，故曰阳生阴长，此阴阳之治也。阳之亢者为焦枯，阴之凝者为封闭，故曰阳杀阴藏，此阴阳之乱也。《天元
纪大论》曰∶天以阳生阴长，地以阳杀阴藏。夫天为阳，阳主于升，升则向生，故曰天以阳生阴长，阳中有阴
也。地为阴，阴主于降，降则向死，故曰地以阳杀阴藏，阴中有阳也，此言岁纪也。上半年为阳升，天气主之，
故春生夏长；下半年为阴降，地气主之，故秋收冬藏。阳不独立，得阴而后成，如发生赖于阳和，而长养由乎雨
露，故曰阳生阴长。阴不自专，因阳而后行，如闭藏因于寒冽，而肃杀出乎风霜，故曰阳杀阴藏。按∶三说俱
通，故并存之。第二则本乎经文，尤为确当。愚意万物皆听命于阳，而阴特为之顺承者也。阳气生旺，则阴血
赖以长养；阳气衰杀，则阴血无由和调，此阴从阳之至理也），阳化气，阴成形（阳无形，故化气；阴有质，
故成形）。寒极生热，热极生寒（冬寒之极，将生春夏之热，冬至以后，自复而之干也。夏热之极，将生秋冬之寒，夏至
以后，自 而之坤也）。
寒气生浊，热气生清（寒属阴，故生浊。热属阳，故生清），清气在下，则生飧泄，浊气在上，则生 胀
（清阳主升，阳陷于下而不能升，故为飧泄，完谷不化也。浊阴主降，阴逆于上而不能降，故为 胀，胸膈胀
满也）。
清阳为天，浊阴为地，地气上为云，天气下为雨（此以下，明阴阳之升降，天人一理也。阴在下者为精，
精即水也，精升则化为气，云因雨而出也。阳在上者为气，气即云也，气降即化为精，雨由云而生也。自下而
上者，地交于天，故地气上为云。自上而下者，天交于地，故天气下为雨。就天地而言，谓之云雨；就人身而言，谓之
精气，人身一小天地，讵不信然）。
故清阳出上窍，浊阴出下窍（上有七窍，耳目口鼻也。下有二窍，前阴、后阴也），清阳发腠理，浊阴走五
脏；清阳实四肢，浊阴归六腑（阳位乎外，阴位乎内，腠理四肢皆在外者，故清阳居之，五脏六腑皆在内者，
故浊阴居之）。
水为阴，火为阳（水润下而寒，故为阴；火炎上而热，故为阳。炎上者，欲其下降。润下者，欲其上
升，谓之水火交而成既济。火不制其上炎，水不禁其就下，谓之水火不交而成未济。肾者水也，水中生气，即真
火也。心者火也，火中生液，即真水也。阴中有阳，阳中有阴，水火互藏，阴阳交体，此又不可不知者也）；
阳为气，阴为味；味归形，形归气（气无形而升，故为阳；味有质而降，故为阴。味归形者，五味入口，生血
成形也。形归气者。血皆倚赖于气，气旺则自能生血，气伤而血因以败也）；气归精，精归化（气者，先天之
元气与后天之谷气并而充身者也。肺金主之，金施气以生水，水即精也。精者，坎府之真铅，天一之最先也。
精施则能化生，万化之本元也）；精食气，形食味（气为精母，味为形本。食者，子食母乳之义也）；
化生精，气生形（万化之生必本于精，形质之生必本于气）；味伤形，气伤精（味本归形，味或不节，反伤形
也。气本归精，气或不调，反伤精也）；精化为气，气伤于味（气本归精，气为精母也。此云精化为气者，精
亦能生气也。如不好色者，气因以旺也。水火互为之根，即上文天地云雨之义也。味不节则伤形，而气不免
焉。如味过于酸，肝气以津，脾气乃绝之类）。阴味出下窍，阳气出上窍（味为阴，故下；气为阳，故上），
味浓者为阴，薄为阴之阳；气浓者为阳，薄为阳之阴（味属阴，味浓为纯阴，味薄为阴中之阳。气属阳，气浓
为纯阳，气薄为阳中之阴）。味浓则泄，薄则通；气薄则发泄，浓则发热（阴味下行，味浓者能泄于下，味薄
者能通利也，阳气上行，故气薄者能泄于表，气浓者能发热也）。壮火之气衰，少火之气壮；壮火食气，气食
少火；壮火散气，少火生气（火者，阳气也。天非此火不能发育万物，人非此火不能生养命根，是以物生必本于阳。但
阳和之火则生物，亢烈之火则害物，故火太过则气反衰，火和平则气乃壮。壮火散气，故云食气。少火
生气，故云食火，阳气者，身中温暖之气也。此气绝，则身冷而毙矣。营运三焦，熟腐五谷，畴非真火之功，
是以《内经》谆谆反复，欲人善养此火，但少则壮，壮则衰，特须善为调剂。世之善用苦寒、好行疏伐者，讵非
岐黄之罪人哉）。
阴胜则阳病，阳胜则阴病；阳胜则热，阴胜则寒（阴阳和则得其平，一至有偏胜，病斯作矣），重寒则热，
重热则寒（阴阳之变，水极则似火，火极则似水，阳盛则隔阴，阴盛则隔阳，故有内真寒而外假热，内真热而
外假寒之症。不察其变，妄轻投剂，如水益深，如火益热。虽有智者，莫可挽救矣）；寒伤形，热伤气（寒属
阴，形亦属阴，故寒则形消也，热为阳，气亦为阳，故热则气散也），气伤痛，形伤肿（气喜宣通，气伤则壅闭
而不通，故痛，形为质象，形伤则稽留而不化，故肿）。故先痛而后肿者，气伤形也；先肿而后痛者，形伤气
也（气先伤而后及于形，气伤为本，形伤为标也。形先伤而后及于气，形伤为本，气伤为标也）。
喜怒伤气，寒暑伤形（举喜怒而悲恐忧统之矣。内伤人情，如喜则气缓，怒则气上，悲则气消，恐则气下，
忧则气结，故曰伤气。举寒暑而风湿燥统之矣。外伤天气，如风胜则动，热胜则肿，燥胜则干，寒胜则浮，湿
胜则泻，故曰伤形）。
天不足西北，故西北方阴也，而人右耳目不如左明也。地不满东南，故东南方阳也，而人左手足不如右强也
（天为阳。西北阴方，故天不足西北，地为阴，东南阳方，故地不满东南，日月星辰，天之四象，犹人之有耳目
口鼻，故耳目之左明于右，以阳胜于东南也。水火金木，地之四体，犹人之有皮肉筋骨，故手足之右强于左，以
阴强于西北也）。
阳之汗，以天地之雨名之（汗出从表，阳也，而本于阴水之属，故以天地之雨应之。雨虽属阴，非天之阳
气降，则不雨也。知雨之义者，知汗之故矣）；阳之气，以天地之疾风名之（气为阳，阳胜则气逆喘急，如天地之疾风，
阳气鼓动也）。
《金匮真言论》曰∶平旦至日中，天之阳，阳中之阳也；日中至黄昏，天之阳，阳中之阴也；合夜至鸡鸣，
天之阴，阴中之阴也；鸡鸣至平旦，天之阴，阴中之阳也（子、午、卯、酉，天之四正也，平旦至日中，自卯
至午也；日中至黄昏，自午至酉也∶合夜至鸡鸣，自酉至子也；鸡鸣至平旦，自子至卯也。以一日分四时，
则子、午当二至，卯酉当二分，日出为春，日中为夏，日入为秋，夜半为冬也）。
夫言人之阴阳，则外为阳，内为阴（以表里言）；言人身之阴阳，则背为阳，腹为阴（以前后言）；言人身
之脏腑中阴阳，则脏者为阴，腑者为阳，肝、心、脾、肺、肾五脏皆为阴，胆、胃、大肠、小肠、膀胱、三焦，
六腑皆为阳（五脏属里，藏精气而不泻，故为阴。六腑属表，传化物而不藏，故为阳）。
故背为阳，阳中之阳，心也；背为阳，阳中之阴，肺也；腹为阴，阴中之阴，肾也；腹为阴，阴中之阳，
肝也；腹为阴，阴中之至阴，脾也（老子曰，负阴而抱阳，是以腹为阳、背为阴也。《内经》乃以背为阳、腹为
阴，何也？邵子曰∶天之阳在南，故日处之；地之刚在北，故山处之，然则老子之说言天象也，《内经》之说
言地象也，况阳经行于背，阴经行于腹，人身脏腑之形体，本为地象也，第考伏羲六十四卦方圆二图，其义显
然，夫圆图象天，阳在东南，方图象地，阳在西北，可以洞然无疑矣。心肺为背之阳，肝脾肾为腹之阴，何也？
心肺在膈上，连近于背，故为背之二阳脏。肝脾肾在膈下，附近于腹，故为腹之三阴脏。然阳中又分阴阳者，
心象人身之日，故为阳中之阳；肺象人身之天，天体虽阳，色玄而不自明，包藏阴德，比之太阳有间；故肺为阳中
之阴。阴中又分阴阳者，肾属水，故为
阴中之阴；肝属木，故为阴中之阳；脾属坤土，故为阴中之至阴也）。
《阴阳应象大论》说：阴阳，是天地运行的根本规律（太极运动而产生阳，静止而产生阴，天主要体现为动，地主要体现为静。《易经》说：一阴一阳交替变化就叫做道。阴阳是道的本体所生，道是通过阴阳来显现的），是万物的总纲（总体来看是纲，体现大德的化育；纷繁复杂来看是纪，体现小德的川流不息），是万物变化的根源（经文说：事物的生长叫做“化”，事物发展到极点叫做“变”。《易经》说：在天上形成形象，在地上形成形体，变化就显现了。朱熹说：变是化的渐进过程，化是变的完成结果。阴可以变为阳，阳可以变为阴，虽然变化繁多，但没有不统摄于阴阳的，所以称为父母），是生命生杀的根本起始（阴阳相交则万物生，阴阳隔绝则万物死，阳气来临则物生，阴气到来则物死，万物的生死没有不以阴阳为根本起始的），也是神机变化的府库（变化莫测叫做“神”，万物生成显形叫做“明”。府库，是说变化和生成都从这里产生）。治病必须探求根本（人的疾病，虽然原因不一，但有的属虚，有的属实，有的属寒，有的属热，有的在气分，有的在血分，有的在脏，有的在腑，都不超出阴阳的范围，所以知道病变无穷无尽，而阴阳是其根本。经文说：懂得要领的人，一句话就能概括全貌。只要辨明虚实，就能辨别阴阳，然而在疑似之间很难分辨清楚。比如极度虚弱却出现盛实的假象，如果误用泻法就会冤枉病人；极度实邪却出现羸弱的假象，如果误用补法只会加重病情；阴证似阳证，用清热法必然失败；阳证似阴证，用温补法必然导致死亡。气主温煦，血主濡润，补气药有生血的功效，补血药没有益气的道理。病在腑却误攻其脏，叫做引贼入门；病在脏却误攻其腑，好比隔靴搔痒。只有洞察阴阳，直透病本，才堪当司命之职。如果在疑似之际，混淆不清，在攻补之间，畏惧不敢下手，造成“实实虚虚”（使实证更实、虚证更虚）的祸害，怎么忍心说出口呢）。
因此，积聚的阳气成为天，积聚的阴气成为地。阴气宁静，阳气躁动（积聚，是汇聚的意思。集合一切属于阳的事物，没有不本源于天的；集合一切属于阴的事物，没有不本源于地的。阴主静，阳主动，这是它们的本性），阳气生发，阴气成长，阳气肃杀，阴气闭藏（阳的和缓之气用于发育，阴的和缓之气用于成实，所以说“阳生阴长”，这是阴阳调和的状态。阳的亢烈之气导致焦枯，阴的凝滞之气导致封闭，所以说“阳杀阴藏”，这是阴阳失调的状态。《天元纪大论》说：天以阳生阴长，地以阳杀阴藏。天属阳，阳主升，升则趋向生，所以说“天以阳生阴长”，这是阳中有阴。地属阴，阴主降，降则趋向死，所以说“地以阳杀阴藏”，这是阴中有阳。这是在讲岁序的变化。上半年为阳升，由天气主导，所以春生夏长；下半年为阴降，由地气主导，所以秋收冬藏。阳不能独立存在，得到阴之后才能成就，如发生依赖于阳和之气，而长养依靠于雨露，所以说“阳生阴长”。阴不能独自专行，凭借阳之后才能运行，如闭藏因为寒冽，而肃杀出于风霜，所以说“阳杀阴藏”。按：这三种说法都通顺，所以并存。第二种说法基于经文，尤为确切。我的意思是万物都听命于阳，而阴只是顺承它罢了。阳气生旺，阴血就依赖它来长养；阳气衰杀，阴血就无法调和，这是阴从属于阳的最高真理），阳气化生功能（气），阴气构成形体（质）（阳无形体，所以化生功能；阴有实质，所以构成形体）。寒到极点产生热，热到极点产生寒（冬季寒冷至极，将要产生春夏的热，冬至以后，自然从复卦走向干卦。夏季炎热至极，将要产生秋冬的寒，夏至以后，自然从姤卦走向坤卦）。
寒气产生浊阴，热气产生清阳（寒属阴，所以产生浊；热属阳，所以产生清），清阳在下，就会产生完谷不化的泄泻，浊阴在上，就会产生胸膈胀满（清阳主升，阳气陷于下而不能上升，所以发生飧泄，即大便中有未消化的食物。浊阴主降，阴气逆于上而不能下降，所以发生痞胀，即胸膈胀满）。
清阳为天，浊阴为地，地气上升变成云，天气下降变成雨（以下阐明阴阳的升降，天人同理。阴在下者为精，精就是水，精上升就化为气，云因雨而出。阳在上者为气，气就是云，气下降就化为精，雨由云而生。自下而上，是地交于天，所以地气上为云。自上而下，是天交于地，所以天气下为雨。就天地而言，叫做云雨；就人身而言，叫做精气，人身是小天地，难道不是这样吗）。
所以清阳出于上窍，浊阴出于下窍（上有七窍，即耳、目、口、鼻；下有二窍，即前阴和后阴），清阳发散于腠理，浊阴走注于五脏；清阳充实四肢，浊阴归入六腑（阳位在外，阴位在内，腠理和四肢都在外，所以清阳居之；五脏六腑都在内，所以浊阴居之）。
水是阴，火是阳（水润下且寒，所以为阴；火炎上且热，所以为阳。炎上的火，希望它下降；润下的水，希望它上升，这叫做水火相交而成既济卦。火不制约其上炎，水不禁止其就下，这叫做水火不交而成未济卦。肾属水，水中生气，就是真火。心属火，火中生液，就是真水。阴中有阳，阳中有阴，水火互藏，阴阳交体，这又不可不知道）。
阳指气，阴指味；味滋养形体，形体依赖气（气无形而升，所以为阳；味有质而降，所以为阴。“味归形”的意思是：五味入口，能生血成形。“形归气”的意思是：血都依赖气，气旺盛则自然能生血，气受伤则血随之败坏）。气滋养精，精转化为气化（气，是先天的元气与后天的谷气结合充养身体的。肺金主管它，金施气以生水，水就是精。精，是坎宫的真铅，天一最先产生的。精施化就能化生万物，是万化的本源）。精消耗气，形体消耗味（气是精的母亲，味是形体的根本。“食”字，取儿子吃母乳的含义）。气化生精，气生成形体（万物的化生必以精为本，形质的生成必以气为本）。味损伤形体，气损伤精（味本归形，如果味道不节制，反而伤形。气本归精，如果气不调和，反而伤精）。精转化为气，气被味所伤（气本归精，气是精的母亲。这里说“精化为气”，是因为精也能生气。如不好色的人，气因此旺盛。水火互为根本，即上文天地云雨的意义。味不节制则伤形，气也难免受损。如味过于酸，肝气津溢，脾气乃绝之类）。阴味出于下窍，阳气出于上窍（味属阴，所以下行；气属阳，所以上行），味浓的为纯阴，味薄的为阴中之阳；气浓的为纯阳，气薄的为阳中之阴（味属阴，味浓为纯阴，味薄为阴中之阳。气属阳，气浓为纯阳，气薄为阳中之阴）。味浓则泄下，味薄则通利；气薄则发泄于表，气浓则发热（阴味下行，味浓者能在下泄，味薄者能通利。阳气上行，所以气薄者能发泄于体表，气浓者能发热）。壮火使人气衰退，少火使人气旺盛；壮火吞噬气，气滋养少火；壮火耗散气，少火滋生气（火，就是阳气。天没有这个火不能发育万物，人没有这个火不能生养命根，所以万物生成必本于阳。但是温和的火能生物，亢烈的火则害物，所以火太过则气反而衰退，火和平则气才旺盛。壮火耗散气，所以说“食气”。少火滋生气，所以说“食火”。阳气，是身体中温暖的气。这种气断绝，身体就会冷而死。营运三焦，熟腐五谷，哪不是真火的功劳，所以《内经》谆谆反复，想要人善于保养此火，只是少则壮，多则衰，特别需要善于调剂。世上那些善用苦寒药、喜欢进行疏伐的人，岂不是岐黄之术的罪人吗）。
阴偏胜则阳受病，阳偏胜则阴受病；阳偏胜则热，阴偏胜则寒（阴阳平和则得其平衡，一旦有偏胜，病就产生了），重寒则现热象，重热则现寒象（阴阳的变化，水极则像火，火极则像水，阳盛则格拒阴，阴盛则格拒阳，所以有内真寒而外假热，内真热而外假寒的症状。不考察其变化，妄然轻率投药，如同水越加越深，火越加越热。即使有智者，也无法挽救了）。寒邪损伤形体，热邪损伤气（寒属阴，形亦属阴，所以寒则形体消瘦；热为阳，气亦为阳，所以热则气散）。气伤则痛，形伤则肿（气喜欢宣通，气伤则壅闭而不通，所以痛；形为质象，形伤则稽留而不化，所以肿）。所以先痛而后肿的，是气伤及形；先肿而后痛的，是形伤及气（气先伤而后波及形，气伤为本，形伤为标。形先伤而后波及气，形伤为本，气伤为标）。
喜怒损伤气，寒暑损伤形体（列举喜怒，悲恐忧也就包括在内了。内伤情志，如喜则气缓，怒则气上，悲则气消，恐则气下，忧则气结，所以说伤气。列举寒暑，风湿燥也就包括在内了。外感天时，如风胜则动摇，热胜则肿胀，燥胜则干燥，寒胜则浮肿，湿胜则泄泻，所以说伤形）。
天不足于西北方，所以西北方属阴，人的右耳目不如左耳目明亮。地不满于东南方，所以东南方属阳，人的左手足不如右手足强壮（天为阳。西北是阴方，所以天不足西北；地为阴，东南是阳方，所以地不满东南。日月星辰是天的四象，犹如有耳目口鼻，所以耳目的左边比右边明亮，是因为阳胜于东南。水火金木是地的四体，犹如有皮肉筋骨，所以手足的右边比左边强壮，是因为阴强于西北）。
阳的汗，用天地的雨来命名（汗出从表，属阳，但本于阴水一类，所以用天地的雨来对应。雨虽属阴，但不是天的阳气下降，就不会下雨。懂得雨的意义，就懂得汗的缘故了）；阳的气，用天地的疾风来命名（气为阳，阳胜则气逆喘急，如同天地的疾风，是阳气鼓动的表现）。
《金匮真言论》说：平旦到日中，是天的阳，阳中之阳；日中到黄昏，是天的阳，阳中之阴；合夜到鸡鸣，是天的阴，阴中之阴；鸡鸣到平旦，是天的阴，阴中之阳（子、午、卯、酉，是天的四个正位。平旦到日中，是从卯到午；日中到黄昏，是从午到酉；合夜到鸡鸣，是从酉到子；鸡鸣到平旦，是从子到卯。将一天分为四时，则子、午对应二至，卯、酉对应二分，日出为春，日中为夏，日入为秋，夜半为冬）。
说到人的阴阳，则外为阳，内为阴（从表里来说）；说到人身部的阴阳，则背为阳，腹为阴（以前后来说）；说到人身脏腑中的阴阳，则脏者为阴，腑者为阳，肝、心、脾、肺、肾五脏皆为阴，胆、胃、大肠、小肠、膀胱、三焦六腑皆为阳（五脏属里，藏精气而不泻，所以为阴。六腑属表，传化物而不藏，所以为阳）。
所以背为阳，阳中之阳是心；背为阳，阳中之阴是肺；腹为阴，阴中之阴是肾；腹为阴，阴中之阳是肝；腹为阴，阴中之至阴是脾（老子说，背负阴而怀抱阳，所以认为腹为阳、背为阴。《内经》却认为背为阳、腹为阴，为什么呢？邵雍说：天的阳在南，所以太阳处在那里；地的刚在北，所以山处在那里。那么老子的说法讲的是天象，《内经》的说法讲的是地象。况且阳经行于背，阴经行于腹，人身脏腑的形体，本来就像地象。只要考察伏羲六十四卦方圆二图，其意义显然无疑。圆图象天，阳在东南；方图象地，阳在西北，可以洞然无疑了。心肺位于背之阳，肝脾肾位于腹之阴，为什么呢？心肺在膈上，靠近背部，所以是背的两个阳脏。肝脾肾在膈下，靠近腹部，所以是腹的三个阴脏。然而阳中又分阴阳，心象人身之日，所以为阳中之阳；肺象人身之天，天体虽阳，颜色玄黑而不自明，包藏阴德，比起太阳有所不及；所以肺为阳中之阴。阴中又分阴阳，肾属水，所以为阴中之阴；肝属木，所以为阴中之阳；脾属坤土，所以为阴中之至阴也）。
The *Da Lun on Yin-Yang Responding to Phenomena* states: Yin and Yang are the fundamental laws of Heaven and Earth (Taiji moves to generate Yang, and remains still to generate Yin; Heaven primarily embodies movement, while Earth primarily embodies stillness. The *I Ching* says: "One Yin and one Yang is called the Dao." Yin and Yang are generated from the substance of the Dao, and the Dao is manifested through Yin and Yang), the general principles of all things (In general, they serve as the guiding principle, reflecting the great virtue of transformation; in their complexity, they serve as the threads, reflecting the small virtue of flowing like rivers), the parents of all changes (The classic states: "Growth of things is called 'Hua' (transformation); reaching the extreme is called 'Bian' (change)." The *I Ching* says: "Images formed in Heaven, shapes formed on Earth, and changes become visible." Zhu Xi said: "Bian is the gradual process of Hua, and Hua is the completion of Bian." Yin can change into Yang, and Yang into Yin. Although changes are numerous, none are not governed by Yin and Yang, hence they are called parents), the origin of life and death (When Yin and Yang interact, things are born; when they separate, things die. When Yang arrives, things live; when Yin arrives, things die. The birth and death of all things take Yin and Yang as their fundamental origin), and the residence of spiritual phenomena (Unpredictable change is called "Shen" (spirit/mystery); the generation and manifestation of all things is called "Ming" (clarity). "Fu" (residence/storehouse) means that changes and manifestations all originate from here). In treating disease, one must seek the root (Human diseases, though diverse in cause, may belong to deficiency or excess, cold or heat, Qi or Blood, Zang or Fu organs. None fall outside the scope of Yin and Yang. Thus, knowing that pathological changes are infinite, yet Yin and Yang are their root. The classic says: "He who understands the essentials needs but one word to conclude." By clearly distinguishing deficiency and excess, one distinguishes Yin and Yang. However, it is difficult to differentiate between similar and deceptive presentations. For instance, extreme deficiency presenting with excess symptoms: misusing purgation causes injustice to the patient. Extreme excess presenting with debility: misusing tonification aggravates the disease. Yin syndrome resembling Yang: using clearing methods leads to failure. Yang syndrome resembling Yin: using warming methods leads to demise. Qi provides warmth; Blood provides nourishment. Qi-tonifying herbs have the merit of generating Blood, but Blood-nourishing herbs lack the function of benefiting Qi. Attacking the Zang organs when the disease is in the Fu organs is like inviting thieves indoors; attacking the Fu organs when the disease is in the Zang organs is like scratching an itch through a boot. Only by penetrating Yin and Yang and directly reaching the root of the disease can one be fit to act as a guardian of life. If, during deceptive moments, one confuses the clear and the obscure, and hesitates between attack and tonification, causing the disaster of "reinforcing excess and depleting deficiency," how could one bear to speak of it?).
Therefore, accumulated Yang becomes Heaven, and accumulated Yin becomes Earth. Yin is quiet, Yang is restless (Accumulation refers to gathering. All things belonging to Yang originate from Heaven; all things belonging to Yin originate from Earth. Yin governs stillness, Yang governs restlessness; this is their nature). Yang generates, Yin grows; Yang kills, Yin stores (The harmonious aspect of Yang promotes development; the harmonious aspect of Yin promotes maturation. Hence, "Yang generates, Yin grows," which represents the governance of Yin and Yang. The excessive aspect of Yang leads to scorching and withering; the stagnant aspect of Yin leads to closure. Hence, "Yang kills, Yin stores," which represents the disorder of Yin and Yang. The *Tianyuan Ji Da Lun* states: "Heaven generates through Yang and grows through Yin; Earth kills through Yang and stores through Yin." Heaven is Yang, governing ascent; ascent tends toward life, hence "Heaven generates through Yang and grows through Yin," indicating Yin within Yang. Earth is Yin, governing descent; descent tends toward death, hence "Earth kills through Yang and stores through Yin," indicating Yang within Yin. This discusses the annual cycle. The first half of the year involves Yang ascending, governed by Heavenly Qi, resulting in Spring growth and Summer expansion. The second half involves Yin descending, governed by Earthly Qi, resulting in Autumn harvest and Winter storage. Yang cannot exist independently; it requires Yin to complete it, just as growth relies on warm Yang and nurturing depends on rain and dew, hence "Yang generates, Yin grows." Yin does not act alone; it follows Yang, just as storage depends on cold and desolation arises from wind and frost, hence "Yang kills, Yin stores." Note: All three interpretations are valid, so they are preserved. The second interpretation, based on the classic text, is particularly accurate. My view is that all things obey Yang, while Yin merely follows. When Yang Qi is vigorous, Yin Blood relies on it for nourishment; when Yang Qi declines, Yin Blood cannot harmonize. This is the profound truth of Yin following Yang). Yang transforms into Qi (function/energy), and Yin forms into Structure (material form) (Yang is formless, thus transforming into Qi; Yin has substance, thus forming structure). Extreme cold generates heat, and extreme heat generates cold (Extreme winter cold will generate the heat of spring and summer; after the Winter Solstice, it naturally progresses from the Fu hexagram to the Qian hexagram. Extreme summer heat will generate the cold of autumn and winter; after the Summer Solstice, it naturally progresses from the Gou hexagram to the Kun hexagram).
Cold Qi generates turbid Yin, and Hot Qi generates clear Yang (Cold belongs to Yin, thus generating turbidity; Heat belongs to Yang, thus generating clarity). If clear Yang sinks below, it produces undigested diarrhea; if turbid Yin rises above, it produces chest and diaphragm distension (Clear Yang governs ascending; if Yang sinks below and cannot ascend, it results in Sundun diarrhea, characterized by undigested food in stool. Turbid Yin governs descending; if Yin rebels upward and cannot descend, it results in Pi-Zhang, characterized by chest and diaphragm fullness).
Clear Yang constitutes Heaven, and turbid Yin constitutes Earth. Earthly Qi ascends to become clouds, and Heavenly Qi descends to become rain (Hereinafter, the升降 [ascending and descending] of Yin and Yang is explained, showing the unity of Heaven and Human principles. Yin below is Essence, which is Water. When Essence ascends, it transforms into Qi, and clouds emerge from rain. Yang above is Qi, which is Cloud. When Qi descends, it transforms into Essence, and rain is born from clouds. Ascending from below to above is Earth interacting with Heaven, hence "Earthly Qi ascends to become clouds." Descending from above to below is Heaven interacting with Earth, hence "Heavenly Qi descends to become rain." Regarding Heaven and Earth, these are called clouds and rain; regarding the human body, they are called Essence and Qi. The human body is a microcosm of Heaven and Earth, is it not?).
Thus, clear Yang exits through the upper orifices, and turbid Yin exits through the lower orifices (There are seven orifices above: ears, eyes, mouth, and nose; there are two orifices below: the anterior and posterior yin). Clear Yang disperses into the interstices (Couli), and turbid Yin travels to the Five Zang organs; clear Yang fills the four limbs, and turbid Yin returns to the Six Fu organs (Yang resides externally, Yin resides internally. The interstices and limbs are external, so clear Yang resides there. The Five Zang and Six Fu organs are internal, so turbid Yin resides there).
Water is Yin, Fire is Yang (Water flows downward and is cold, thus Yin; Fire flares upward and is hot, thus Yang. Flaring upward fire desires to descend; flowing downward water desires to ascend. This is called Water and Fire interacting to form the Ji Ji hexagram. If Fire does not control its upward flare, and Water does not restrain its downward flow, it is called Water and Fire not interacting, forming the Wei Ji hexagram. The Kidney is Water; Qi generated within Water is True Fire. The Heart is Fire; Fluid generated within Fire is True Water. Yin contains Yang, and Yang contains Yin; Water and Fire hide within each other, and Yin and Yang interpenetrate. This must be known).
Yang refers to Qi, and Yin refers to Flavor; Flavor returns to Structure, and Structure returns to Qi (Qi is formless and ascending, thus Yang; Flavor has substance and descending, thus Yin. "Flavor returns to Structure" means: flavors entering the mouth generate Blood and form Structure. "Structure returns to Qi" means: Blood relies on Qi; when Qi is prosperous, it naturally generates Blood; when Qi is injured, Blood fails). Qi returns to Essence, and Essence returns to Transformation (Qi consists of congenital Yuan Qi and acquired Grain Qi combined to nourish the body. The Lung Metal governs it; Metal imparts Qi to generate Water, which is Essence. Essence is the True Lead of the Kan palace, the earliest manifestation of Tian Yi. When Essence is imparted, it can transform and generate; it is the origin of all transformations). Essence consumes Qi, and Structure consumes Flavor (Qi is the mother of Essence; Flavor is the root of Structure. "Consume" implies the meaning of a child consuming breast milk). Transformation generates Essence, and Qi generates Structure (The generation of all transformations must be based on Essence; the generation of physical structure must be based on Qi). Flavor injures Structure, and Qi injures Essence (Flavor originally returns to Structure; if flavor is unregulated, it injures Structure. Qi originally returns to Essence; if Qi is disordered, it injures Essence). Essence transforms into Qi, and Qi is injured by Flavor (Qi originally returns to Essence, as Qi is the mother of Essence. Here, "Essence transforms into Qi" means Essence can also generate Qi. For example, those who avoid sexual indulgence see their Qi flourish. Water and Fire are roots of each other, reflecting the meaning of Heaven/Earth clouds/rain mentioned earlier. Unregulated flavor injures Structure, and Qi is inevitably affected. For instance, excessive sour flavor causes Liver Qi to overflow, leading to Spleen Qi exhaustion). Yin Flavor exits through the lower orifices, and Yang Qi exits through the upper orifices (Flavor is Yin, thus descending; Qi is Yang, thus ascending). Strong flavor is Pure Yin, and thin flavor is Yang within Yin; strong Qi is Pure Yang, and thin Qi is Yin within Yang (Flavor belongs to Yin; strong flavor is Pure Yin, thin flavor is Yang within Yin. Qi belongs to Yang; strong Qi is Pure Yang, thin Qi is Yin within Yang). Strong flavor causes purging, and thin flavor causes free flow; thin Qi causes sweating/dispersal, and strong Qi causes fever (Yin Flavor descends; strong flavor purges downward, thin flavor promotes free flow. Yang Qi ascends; thus thin Qi disperses at the surface, and strong Qi causes fever). Vigorous Fire causes Qi to decline, and Mild Fire causes Qi to strengthen; Vigorous Fire consumes Qi, and Qi nourishes Mild Fire; Vigorous Fire dissipates Qi, and Mild Fire generates Qi (Fire is Yang Qi. Without this Fire, Heaven cannot develop all things; without this Fire, humans cannot nourish the root of life. Thus, generation of things must be based on Yang. However, mild Fire generates things, while excessive Fire harms them. Therefore, excessive Fire causes Qi to decline, while balanced Fire makes Qi strong. Vigorous Fire dissipates Qi, hence "consumes Qi." Mild Fire generates Qi, hence "nourished by Fire." Yang Qi is the warm energy in the body. If this Qi ceases, the body becomes cold and dies. Circulating through the San Jiao, cooking and rotting the five grains—none is not the merit of True Fire. Thus, the *Nei Jing* repeatedly urges people to nurture this Fire well. It is only when it is mild that it strengthens, and when excessive that it declines; special care is needed in regulation. Those in the world who skillfully use bitter-cold herbs and prefer to purge and伐 (attack) are surely sinners against the teachings of Qi Bo and Huang Di).
If Yin prevails, Yang is diseased; if Yang prevails, Yin is diseased; Yang prevalence causes Heat, and Yin prevalence causes Cold (When Yin and Yang are in harmony, balance is achieved. Once there is prevalence, disease arises). Extreme Cold presents with Heat signs, and extreme Heat presents with Cold signs (Changes in Yin and Yang: extreme Water resembles Fire, extreme Fire resembles Water. Yang excess repels Yin, Yin excess repels Yang. Thus, there are conditions of true internal cold with false external heat, and true internal heat with false external cold. Failing to investigate these variations and prescribing recklessly is like deepening water or adding heat to fire. Even with wisdom, rescue is impossible). Cold injures Structure, and Heat injures Qi (Cold is Yin, Structure is Yin, so Cold causes Structure to diminish. Heat is Yang, Qi is Yang, so Heat causes Qi to scatter). Qi injury causes Pain, and Structure injury causes Swelling (Qi likes free circulation; Qi injury causes obstruction and blockage, hence Pain. Structure is material form; Structure injury causes stagnation and failure to transform, hence Swelling). Therefore, pain followed by swelling indicates Qi injuring Structure; swelling followed by pain indicates Structure injuring Qi (If Qi is injured first and then affects Structure, Qi injury is the root, and Structure injury is the branch. If Structure is injured first and then affects Qi, Structure injury is the root, and Qi injury is the branch).
Joy and Anger injure Qi, and Cold and Heat injure Structure (Listing Joy and Anger includes Sorrow, Fear, and Worry. Internal emotional injuries: Joy relaxes Qi, Anger raises Qi, Sorrow dissipates Qi, Fear sinks Qi, Worry knots Qi; hence "injures Qi." Listing Cold and Heat includes Wind, Dampness, and Dryness. External climatic injuries: Wind excess causes tremors, Heat excess causes swelling, Dryness excess causes dryness, Cold excess causes edema, Dampness excess causes diarrhea; hence "injures Structure").
Heaven is deficient in the Northwest, so the Northwest direction is Yin, and the right ear and eye of humans are less acute than the left. Earth is incomplete in the Southeast, so the Southeast direction is Yang, and the left hand and foot of humans are not as strong as the right (Heaven is Yang. The Northwest is Yin, so Heaven is deficient in the Northwest. Earth is Yin. The Southeast is Yang, so Earth is incomplete in the Southeast. The Sun, Moon, stars, and planets are the Four Images of Heaven, analogous to the ears, eyes, mouth, and nose of humans. Hence, the left side of the ears and eyes is more acute than the right, because Yang prevails in the Southeast. Water, Fire, Metal, and Wood are the Four Bodies of Earth, analogous to skin, flesh, sinews, and bones of humans. Hence, the right side of hands and feet is stronger than the left, because Yin prevails in the Northwest).
The sweat of Yang is named after the rain of Heaven and Earth (Sweat emerges from the exterior, belonging to Yang, but originates from Yin-Water. Thus, it corresponds to the rain of Heaven and Earth. Although Rain is Yin, without the descending Yang Qi of Heaven, there would be no rain. Understanding the meaning of Rain is understanding the cause of Sweat). The Qi of Yang is named after the violent wind of Heaven and Earth (Qi is Yang. Yang excess causes Qi rebellion and panting, like the violent wind of Heaven and Earth, driven by Yang Qi agitation).
The *Jin Gui Zhen Yan Lun* states: From dawn to noon, it is Heavenly Yang, Yang within Yang; from noon to dusk, it is Heavenly Yang, Yin within Yang; from nightfall to rooster crow, it is Heavenly Yin, Yin within Yin; from rooster crow to dawn, it is Heavenly Yin, Yang within Yin (Zi, Wu, Mao, You are the four cardinal points of Heaven. Dawn to noon is from Mao to Wu; noon to dusk is from Wu to You; nightfall to rooster crow is from You to Zi; rooster crow to dawn is from Zi to Mao. Dividing one day into four seasons, Zi and Wu correspond to the Solstices, Mao and You to the Equinoxes. Sunrise is Spring, Noon is Summer, Sunset is Autumn, Midnight is Winter).
Speaking of human Yin and Yang, the exterior is Yang and the interior is Yin (regarding interior/exterior); speaking of Yin and Yang of the human body, the back is Yang and the abdomen is Yin (regarding anterior/posterior); speaking of Yin and Yang within the Zang-Fu organs, the Zang organs are Yin and the Fu organs are Yang. The Liver, Heart, Spleen, Lung, and Kidney (Five Zang) are all Yin; the Gallbladder, Stomach, Large Intestine, Small Intestine, Bladder, and San Jiao (Six Fu) are all Yang (Five Zang belong to the interior, storing Essence and Qi without draining, thus Yin. Six Fu belong to the exterior, transmitting and transforming without storing, thus Yang).
Therefore, the back is Yang; Yang within Yang is the Heart; the back is Yang; Yin within Yang is the Lung; the abdomen is Yin; Yin within Yin is the Kidney; the abdomen is Yin; Yang within Yin is the Liver; the abdomen is Yin; Ultimate Yin within Yin is the Spleen (Laozi said, "Carrying Yin and embracing Yang," thus considering the abdomen as Yang and the back as Yin. Why does the *Nei Jing* consider the back as Yang and the abdomen as Yin? Shao Yong said: "Heaven's Yang is in the South, where the sun resides; Earth's剛 (firmness) is in the North, where mountains reside." Thus, Laozi's statement describes celestial phenomena, while the *Nei Jing*'s statement describes terrestrial phenomena. Moreover, Yang meridians run along the back, and Yin meridians along the abdomen. The physical form of human Zang-Fu organs is essentially terrestrial. Examining the Square and Round Diagrams of the 64 Hexagrams by Fuxi makes this clear. The Round Diagram images Heaven, with Yang in the Southeast; the Square Diagram images Earth, with Yang in the Northwest. This can be understood without doubt. The Heart and Lung are Yang in the back; the Liver, Spleen, and Kidney are Yin in the abdomen. Why? The Heart and Lung are above the diaphragm, close to the back, hence the two Yang organs of the back. The Liver, Spleen, and Kidney are below the diaphragm, close to the abdomen, hence the three Yin organs of the abdomen. However, Yin and Yang are further divided. The Heart resembles the Sun of the human body, hence Yang within Yang. The Lung resembles the Sky of the human body; although the sky is Yang, its color is dark and self-illuminating is lacking, hiding Yin virtue, falling short of the Sun; hence the Lung is Yin within Yang. Within Yin, the Kidney belongs to Water, hence Yin within Yin. The Liver belongs to Wood, hence Yang within Yin. The Spleen belongs to Kun Earth, hence Ultimate Yin within Yin.)