（素问阴阳离合论 全）
黄帝问曰∶余闻天为阳，地为阴，日为阳，月为阴，大小月三百六十日成一岁，人亦应之。今三阴三阳，不应阴阳，
其故何也？（此言天地之阴阳，无不合于人者。如上为阳，下为阴，前为阳，后为阴，皆其理也。然而三阴三阳，其亦
有不相应者，故疑以为问。）岐伯对曰∶阴阳者，数之可十，推之可百，数之可千，推之可万，万之大不可胜数，然其要
一也。（谓阴阳之道，合之则一，散之则十百千万，亦无非阴阳之变化。故于显微大小，象体无穷，无不有理存焉。然变
化虽多，其要则一，一即理而已。是以人之三阴三阳，亦岂有不应乎天地者哉？此上二节义，又出五营运大论，详运气
类四。）天覆地载，万物方生，未出地者，命曰阴处，名曰阴中之阴；（天覆地载，即阴阳之上下也。凡万物方生者，未
出乎地，处阴之中，故曰阴处。以阴形而居阴分，故又曰阴中之阴也。）则出地者，名曰阴中之阳。（形成于阴而出于阳，
故曰阴中之阳。）阳予之正，阴为之主。（阳正其气，万化乃生；阴主其质，万形乃成。易曰∶干知大始，坤作成物。大
抵阳先阴后，阳施阴受，阳之轻清未形，阴之重浊有质，即此之谓。予，与同。）故生因春，长因夏，收因秋，藏因冬，
失常则天地四塞。（四时阴阳，先后有序，若失其常，则天地四塞矣。四塞者，阴阳痞隔，不相通也。长，上声。塞，入
声。）阴阳之变，其在人者，亦数之可数。（凡如上文者，皆天地阴阳之变也。其在于人，则亦有阴中之阳，阳中之阴，
上下表里，气数皆然，知其数则无不可数矣。数，推测也。数字，上者去声，下者上声。）帝曰∶愿闻三阴三阳之离合也。
（分而言之谓之离，阴阳各有其经也。并而言之谓之合，表里同归一气也。）岐伯曰∶圣人南面而立，前曰广明，后曰太
冲。（云圣人者，崇人道之大宗也。南面而立者，正阴阳之向背也。广，大也。南方者，丙丁之位。天阳在南，故日处之；
人阳亦在南，故七窍处之。易曰∶相见乎离。即广明之谓。且人身前后经脉，任脉循腹里，至咽喉，上颐循面入目；冲
脉循背里，出颃颡，其输上在于大杼。分言之，则任行乎前而会于阳明，冲行乎后而为十二经脉之海，故前曰广明，后
曰太冲；合言之，则任冲名位虽异，而同出一原，通乎表里，此腹背阴阳之离合也。）太冲之地，名曰少阴，少阴之上，
名曰太阳，太阳根起于至阴，结于命门，名曰阴中之阳。（冲脉并少阴而行，故太冲之地为少阴。地者，次也。有少阴之
里，则有太阳之表，阴气在下，阳气在上，故少阴经起于小指之下，太阳经止于小指之侧，故曰少阴之上名太阳也。太
阳之脉起于目，止于足，下者为根，上者为结，故曰根于至阴，结于命门。命门者，目也。此以太阳而合于少阴，故为
阴中之阳。然离则阴阳各其经，合则表里同其气，是为水脏阴阳之离合也。下仿此。）中身而上，名曰广明，广明之下，
名曰太阴，太阴之前，名曰阳明，阳明根起于厉兑，名曰阴中之阳。（中身，身之中半也。中身而上，心之所居，心属火
而通神明，故亦曰广明。心脏之下，太阴脾也，故广明之下，名曰太阴。太阴之表，阳明胃也，故太阴之前，名曰阳明。
阳明脉止于足之次趾，与太阴为表里，故曰根起于厉兑，为阴中之阳。此土脏阴阳之离合也。）厥阴之表，名曰少阳，少
阳根起于窍阴，名曰阴中之少阳。（少阳与厥阴为表里，而少阳止于足之小趾次趾端，故厥阴之表，为阴中之少阳也。所
谓少阳者，以厥阴气尽，阴尽而阳始，故曰少阳。此木脏阴阳之离合也。）是故三阳之离合也。太阳为开，阳明为阖，少
阳为枢。（此总三阳为言也。太阳为开，谓阳气发于外，为三阳之表也。阳明为阖，谓阳气蓄于内，为三阳之里也。少阳
为枢，谓阳气在表里之间，可出可入，如枢机也。然开阖枢者，有上下中之分，亦如上文出地未出地之义，而合乎天地
之气也。）三经者，不得相失也，搏而勿浮，命曰一阳。（三经者，言阳经也。阳从阳类，不得相失也。其为脉也，虽三
阳各有其体，然阳脉多浮，若纯于浮，则为病矣。故但欲搏手有力，得其阳和之象，而勿至过浮，是为三阳合一之道，
故命曰一阳，此三阳脉之离合也。）帝曰∶愿闻三阴。岐伯曰∶外者为阳，内者为阴，然则中为阴。（外者为阳，言表也。
内者为阴，言里也。然则中为阴，总言属里者为三阴如下文也。）其冲在下，名曰太阴，太阴根起于隐白，名曰阴中之阴。
（其冲在下，名曰太阴，以太阴居冲脉之上也。上文曰广明之下，名曰太阴，广明以心为言，冲脉并肾为言，盖心脾肾
三脏，心在南，脾在中，肾在北也。凡此三阳三阴皆首言冲脉者，以冲为十二经脉之海，故先及之，以举其纲领也。太
阴起于足大趾，故根于隐白。以太阴而居阴分，故曰阴中之阴。此下三阴表里离合之义，俱如前三阳经下。后准此。）太
阴之后，名曰少阴，少阴根起于涌泉，名曰阴中之少阴。（脾下之后，肾之位也，故太阴之后，名曰少阴。少阴脉起小趾
之下，斜趋足心，故根于涌泉穴。肾本少阴而居阴分，故为阴中之少阴。）少阴之前，名曰厥阴，厥阴根起于大敦，阴之
绝阳，名曰阴之绝阴。（肾前之上，肝之位也，故曰少阴之前，名曰厥阴。厥阴起于足大趾，故根于大敦。厥，尽也，绝，
亦尽也。此阴极之经，故曰阴之绝阳，又曰阴之绝阴。）是故三阴之离合也，太阴为开，厥阴为阖，少阴为枢。（此总三
阴为言，亦有内外之分也。太阴为开，居阴分之表也。厥阴为阖，居阴分之里也。少阴为枢，居阴分之中也，开者主出，
阖者主入，枢者主出入之间，亦与三阳之义同。）三经者，不得相失也，搏而勿沉，名曰一阴。（三经皆阴，阴脉皆沉，
不得相失也。若过于沉，则为病矣。故但宜沉搏有神，各得其阴脉中和之体，是为三阴合一之道，故名曰一阴。此三阴
脉之离合也。）阴阳HT HT ，积传为一周，气里形表，而为相成也。（HT HT 一作冲冲，言阴阳之气，运动无已也。
积传为一周，言诸经流传相积，昼夜五十营而为一周也。然形以气而成，气以形而聚，故气运于里，形立于表，交相为
用，此则阴阳表里、离合相成之道也。愚按∶本篇所言，惟足经阴阳，而不及手经者何也？观上文云∶天覆地载，万物
方生，未出地者，命曰阴处，名曰阴中之阴；则出地者，名曰阴中之阳。盖言万物之气，皆自地而升也。而人之腰以上
为天，腰以下为地，言足则通身上下经气皆尽，而手在其中矣，故不必言手也。然足为阴，故于三阳也言阴中之阳，三
阴也言阴中之阴。然则手经亦有离合，其在阳经，当为阳中之阳，其在阴经，当为阳中之阴，可类推矣。言足不言手义，
详疾病类三十九，所当互考。）
《素问·阴阳离合论》（全文）
黄帝问道：我听说天为阳，地为阴，日为阳，月为阴，大月和小月共三百六十日构成一年，人体也与之相应。如今三阴三阳的划分，似乎与天地阴阳不完全对应，这是什么缘故呢？（这段文字说明天地的阴阳，没有不与人体相合的。比如上为阳、下为阴，前为阳、后为阴，都是这个道理。然而三阴三阳，也有看似不相应的地方，所以产生疑问而发问。）
岐伯回答说：阴阳的道理，推演起来可以变成十，再推演可以变成百，数之可至千，推之可至万，万万之多不可胜数，但其要点只有一个。（意思是阴阳之道，合起来就是一个，散开来则是十、百、千万，无非是阴阳的变化。所以在细微与宏大、形象与本体无穷无尽的变化中，无不蕴含道理。虽然变化繁多，但要点只有一个，这个“一”就是理。因此人体的三阴三阳，难道有不顺应天地的吗？以上两节的含义，又见于《五运行大论》，详见运气类第四部分。）
天覆盖于上，地承载于下，万物开始生长。尚未破土而出的，称为处于阴位，名叫阴中之阴；（天覆地载，即指阴阳的上下关系。凡是万物刚开始生长，尚未出于地面，处于阴气之中，所以叫阴处。以阴性的形体居于阴分，所以又叫阴中之阴。）已经破土而出的，名叫阴中之阳。（形体形成于阴而出现在阳，所以叫阴中之阳。）阳气赋予其正气，阴气主宰其形质。（阳气端正其气机，万物化生才得以发生；阴气主宰其形质，万物形态才得以成就。《易经》说：“乾知大始，坤作成物。”大致上是阳先阴后，阳施予阴接受，阳的轻清之气尚未成形，阴的重浊之气已有实质，说的就是这个意思。“予”通“与”。）所以生命因春而生，因夏而长，因秋而收，因冬而藏，如果违背了常态，天地四时就会闭塞不通。（四季阴阳，先后有序，如果失去常态，天地四时就会闭塞。所谓“四塞”，是指阴阳痞隔，不相交通。“长”读上声，“塞”读入声。）
阴阳的变化，在人体身上，也是可以推算出来的。（凡像上文所说的那些，都是天地阴阳的变化。在人体身上，也有阴中之阳、阳中之阴，以及上下表里的区别，气数的规律都是一样的，知道了这些数，就没有不能推算的了。“数”意为推测。“数字”中，“数”作去声，“字”作上声。）
黄帝说：我想听听三阴三阳的离合情况。（分开来说叫做“离”，因为阴阳各有其经脉。合并来说叫做“合”，因为表里同归于一气。）
岐伯说：圣人面向南方站立，前面称为广明，后面称为太冲。（说“圣人”，是推崇人道的大宗。“南面而立”，是为了端正阴阳的向背关系。“广”，意为大。南方是丙丁火的位置。天阳在南，所以太阳位于此处；人阳也在南，所以七窍位于此处。《易经》说：“相见乎离。”这就是“广明”的意思。况且人身前后的经脉，任脉循行于腹内，至咽喉，上行至颐部，沿面部进入目内眦；冲脉循行于背部内侧，出于颃颡（鼻咽部），其输穴上在于大杼。分开来说，任脉行于前而会合于阳明经，冲脉行于后而为十二经脉之海，所以前面叫广明，后面叫太冲；合起来说，任脉和冲脉名称位置虽不同，但同出一源，贯通表里，这就是腹背阴阳的离合关系。）
太冲的部位，名为少阴，少阴之上，名为太阳，太阳经根起于足小趾外侧的至阴穴，结于命门（眼睛），名为阴中之阳。（冲脉并少阴经而行，所以太冲的部位是少阴。“地”意为次级。有少阴之里，就有太阳之表，阴气在下，阳气在上，所以少阴经起于足小趾之下，太阳经止于足小趾之侧，所以说少阴之上名太阳。太阳经的脉气起于目，止于足，下部为根，上部为结，所以说根于至阴，结于命门。命门，指眼睛。这是以太阳经合于少阴经，所以称为阴中之阳。然而分开则阴阳各属一经，合并则表里同属一气，这是水脏（肾与膀胱）阴阳的离合关系。下文仿照此例。）
身体中部以上，名为广明，广明之下，名为太阴，太阴之前，名为阳明，阳明经根起于足次趾端的厉兑穴，名为阴中之阳。（“中身”指身体的中半部分。中身以上，是心脏所在之处，心属火而通神明，所以也叫广明。心脏之下，是太阴脾经，所以广明之下名为太阴。太阴经的表侧，是阳明胃经，所以太阴之前名为阳明。阳明经脉止于足次趾，与太阴经互为表里，所以说根起于厉兑，为阴中之阳。这是土脏（脾与胃）阴阳的离合关系。）
厥阴经的表侧，名为少阳，少阳经根起于足小趾次趾端的窍阴穴，名为阴中之少阳。（少阳与厥阴互为表里，而少阳经止于足小趾和次趾端，所以厥阴的表侧，是阴中之少阳。所谓的“少阳”，是因为厥阴气尽，阴气尽头而阳气始生，所以叫少阳。这是木脏（肝与胆）阴阳的离合关系。）
因此，三阳经的离合情况是：太阳为开，阳明为阖，少阳为枢。（这是对三阳经的总体说法。太阳为开，是说阳气发散于外，是三阳经的表层。阳明为阖，是说阳气蓄积于内，是三阳经的里层。少阳为枢，是说阳气处于表里之间，可出可入，如同枢纽一样。然而开、阖、枢，有上、中、下的区分，也像上文所说的出地与未出地的意义，而与天地之气相合。）这三条经脉，不能相互脱离，脉象搏动有力而不浮越，这就叫做“一阳”。（“三经”指阳经。阳属于阳类，不能相互脱离。它们的脉象，虽然三阳各有其体，但阳脉多浮，如果纯粹浮泛，那就是病了。所以只要脉搏搏手有力，得到阳气的和缓之象，而不至于过浮，这就是三阳合一的道理，所以叫做“一阳”，这是三阳经脉的离合关系。）
黄帝说：我想听听三阴的情况。
岐伯说：外部为阳，内部为阴，那么中间也为阴。（外部为阳，指体表。内部为阴，指体内。那么中间也为阴，总括来说属于里层的即为三阴，如下文所述。）冲脉在下部，名为太阴，太阴经根起于足大趾内侧的隐白穴，名为阴中之阴。（冲脉在下部，名为太阴，是因为太阴位居冲脉之上。上文说广明之下名为太阴，广明是以心而言，冲脉并肾而言，大概心、脾、肾三脏，心在南，脾在中，肾在北。凡是这里三阳三阴都首先提到冲脉的，是因为冲脉是十二经脉之海，所以先提及它，以举出纲领。太阴经起于足大趾，所以根于隐白穴。以太阴经居于阴分，所以叫阴中之阴。以下三阴表里离合的意义，都如同前三阳经所述。后文以此为准。）
太阴经之后，名为少阴，少阴经根起于足心的涌泉穴，名为阴中之少阴。（脾脏之下后方，是肾脏的位置，所以太阴之后名为少阴。少阴经脉起于足小趾之下，斜向足心，所以根于涌泉穴。肾本属少阴而居于阴分，所以为阴中之少阴。）
少阴经之前，名为厥阴，厥阴经根起于足大趾外侧的大敦穴，阴气至极，阳气断绝，名为阴之绝阴。（肾脏前方上方，是肝脏的位置，所以曰少阴之前名为厥阴。厥阴经起于足大趾，所以根于大敦穴。“厥”意为尽，“绝”也是尽的意思。这是阴气极盛的经脉，所以叫阴之绝阳，又叫阴之绝阴。）
因此，三阴经的离合情况是：太阴为开，厥阴为阖，少阴为枢。（这是对三阴经的总体说法，也有内外之分。太阴为开，居于阴分的表层。厥阴为阖，居于阴分的里层。少阴为枢，居于阴分的中间。开者主外出，阖者主内入，枢者主出入之间，这也与三阳经的意义相同。）这三条经脉，不能相互脱离，脉象沉取搏动有神而不沉伏，这就叫做“一阴”。（三经皆属阴，阴脉皆沉，不能相互脱离。如果过于沉伏，那就是病了。所以只宜沉取搏动有神，各得阴脉中和的体态，这就是三阴合一的道理，所以名叫“一阴”。这是三阴经脉的离合关系。）
阴阳之气冲冲不息，循环传递构成一周，气行于里，形立于表，从而相互成就。（“冲冲”一作“冲冲”，形容阴阳之气运动不停止。积传为一周，指诸经流传相互积累，昼夜五十营血循环为一周。然而形体由气而成，气依附形体而聚，所以气运于里，形立于表，交互为用，这就是阴阳表里、离合相成的道理。愚按：本篇所说的，只有足经的阴阳，而没有涉及手经，为什么呢？看上文说：“天覆地载，万物方生，未出地者，命曰阴处，名曰阴中之阴；则出地者，名曰阴中之阳。”这说的是万物的气，都是从地上升起的。而人的腰以上为天，腰以下为地，讲足经就涵盖了全身的经气，手经也就包含在其中了，所以不必单独言及手经。然而足属阴，所以在三阳经中说“阴中之阳”，在三阴经中说“阴中之阴”。那么手经也有离合，在手阳经中，应当是“阳中之阳”，在手阴经中，应当是“阳中之阴”，可以类推。只言足不言手的意义，详见疾病类第三十九篇，应当互相考证。）
*The Suwen: Treatise on the Separation and Union of Yin and Yang* (Full Text)
Huangdi asked, saying: I have heard that Heaven is Yang, Earth is Yin; the Sun is Yang, the Moon is Yin. A year consists of three hundred and sixty days from large and small months, and the human body corresponds to this. Now, the division of Three Yin and Three Yang does not seem to fully correspond to the Yin and Yang of Heaven and Earth. What is the reason for this? (This passage states that the Yin and Yang of Heaven and Earth are in harmony with humanity. For instance, above is Yang, below is Yin; anterior is Yang, posterior is Yin; these are all principles. However, there are aspects of Three Yin and Three Yang that appear not to correspond, hence the doubt and inquiry.)
Qibo replied: The principle of Yin and Yang, when counted, can extend to ten; when deduced, to a hundred; counted further, to a thousand; deduced further, to ten thousand. Even up to myriad myriads, they are countless, yet their essence remains one. (This means that the Way of Yin and Yang, when united, is one; when dispersed, it becomes ten, hundred, thousand, or myriad, all of which are merely transformations of Yin and Yang. Thus, whether in the subtle or the gross, in form or substance, without limit, there is always principle involved. Although changes are numerous, their core is singular; this "one" is Principle. Therefore, how could the Three Yin and Three Yang of the human body fail to accord with Heaven and Earth? The meaning of the preceding two sections also appears in *Da Lun of the Five Movements and Six Qi*; see detailed discussion in Category Four of Yunqi.)
Heaven covers above, Earth bears below, and all things begin to grow. Those that have not yet emerged from the earth are said to dwell in a Yin position, named Yin within Yin; (Heaven covering and Earth bearing refer to the upper and lower aspects of Yin and Yang. All things just beginning to grow, having not yet exited the ground, reside within Yin, thus called "Yin position." Possessing a Yin form residing in a Yin sector, they are again called "Yin within Yin.") Those that have emerged from the earth are named Yang within Yin. (Form arises from Yin but manifests in Yang, thus called "Yang within Yin.") Yang provides the correct Qi, while Yin serves as the master of substance. (Yang rectifies its Qi, allowing the transformation of all things to arise; Yin masters its substance, allowing the forms of all things to be completed. The *I Ching* says: "Qian knows the great beginning, Kun completes the work." Generally, Yang precedes and Yin follows; Yang acts and Yin receives. Yang's light and clear nature is unformed, while Yin's heavy and turbid nature has substance; this is what is meant. "Yu" is synonymous with "yu" [to give].) Thus, life arises due to Spring, grows due to Summer, harvests due to Autumn, and stores due to Winter. If the normal order is violated, the four seasons of Heaven and Earth will become blocked. (The Yin and Yang of the four seasons follow an orderly sequence. If the norm is lost, the four seasons of Heaven and Earth will become obstructed. "Four blockages" refers to the stagnation of Yin and Yang, preventing mutual communication. "Zhang" is pronounced with the rising tone; "Sai" is pronounced with the entering tone.)
The variations of Yin and Yang, as they exist in humans, are also calculable. (All such phenomena described above are variations of Heaven and Earth's Yin and Yang. In humans, there are also Yang within Yin, Yin within Yang, and distinctions of upper/lower and exterior/interior. The numerical patterns are consistent; knowing these numbers allows for calculation. "Shu" means deduction/prediction. In the term "Shu Zi," "Shu" is pronounced with the departing tone, and "Zi" with the rising tone.)
Huangdi said: I wish to hear about the separation and union of Three Yin and Three Yang. (Speaking separately is called "Separation," because Yin and Yang each have their own meridians. Speaking jointly is called "Union," because interior and exterior return to a single Qi.)
Qibo said: When the Sage stands facing South, the front is called Guangming (Broad Brightness), and the back is called Taichong (Great Surge). ("Sage" refers to the great ancestor of human ways. "Facing South" is to align with the orientation of Yin and Yang. "Guang" means large. The South is the position of Bing-Ding Fire. Heavenly Yang is in the South, where the Sun resides; Human Yang is also in the South, where the seven orifices reside. The *I Ching* says: "They meet in Li." This refers to Guangming. Furthermore, regarding the meridians of the front and back of the body: the Ren Mai (Conception Vessel) circulates inside the abdomen, reaches the throat, ascends to the chin, runs along the face, and enters the eyes; the Chong Mai (Penetrating Vessel) circulates inside the back, emerges at the pharynx, and its transport points ascend to Dazhu (BL11). Speaking separately, Ren Mai travels anteriorly and converges with the Yangming Meridian, while Chong Mai travels posteriorly and serves as the Sea of the Twelve Meridians. Hence, the front is called Guangming, and the back is called Taichong. Speaking jointly, although Ren and Chong have different names and positions, they originate from the same source and connect interior and exterior. This is the separation and union of the Yin and Yang of the abdomen and back.)
At the location of Taichong, it is named Shaoyin (Lesser Yin). Above Shaoyin is named Taiyang (Greater Yang). Taiyang originates at Zhiyin (BL67) and knots at Mingmen (the eyes), named Yang within Yin. (Chong Mai runs alongside Shaoyin, so the location of Taichong is Shaoyin. "Di" here means secondary/subordinate. With the interior of Shaoyin, there is the exterior of Taiyang; Yin Qi is below, Yang Qi is above. Thus, Shaoyin Meridian begins below the little toe, and Taiyang Meridian ends beside the little toe, hence "Above Shaoyin is named Taiyang." The Taiyang meridian qi starts at the eye and ends at the foot; the lower part is the root, the upper part is the knot. Hence, rooted at Zhiyin, knotted at Mingmen. Mingmen refers to the eyes. This combines Taiyang with Shaoyin, thus called Yang within Yin. However, when separated, Yin and Yang belong to separate meridians; when united, interior and exterior share the same Qi. This is the separation and union of the Water Organ (Kidney and Bladder). The following examples follow this pattern.)
Above the middle of the body is named Guangming. Below Guangming is named Taiyin (Greater Yin). Anterior to Taiyin is named Yangming (Bright Yang). Yangming originates at Lidui (ST45), named Yang within Yin. ("Zhong Shen" refers to the middle half of the body. Above the middle is the residence of the Heart. The Heart belongs to Fire and connects to Spirit/Mind, thus also called Guangming. Below the Heart is the Taiyin Spleen Meridian, so below Guangming is named Taiyin. The exterior of the Taiyin Meridian is the Yangming Stomach Meridian, so anterior to Taiyin is named Yangming. The Yangming meridian ends at the second toe, forming an interior-exterior relationship with Taiyin. Hence, rooted at Lidui, it is Yang within Yin. This is the separation and union of the Earth Organ (Spleen and Stomach).)
The exterior of Jueyin (Terminal Yin) is named Shaoyang (Lesser Yang). Shaoyang originates at Qiaoyin (GB44), named Lesser Yang within Yin. (Shaoyang and Jueyin are interior-exterior pairs. Shaoyang ends at the tips of the little and second toes. Thus, the exterior of Jueyin is Lesser Yang within Yin. The term "Shaoyang" implies that when Jueyin Qi is exhausted, Yin is exhausted and Yang begins, hence "Shaoyang." This is the separation and union of the Wood Organ (Liver and Gallbladder).)
Therefore, regarding the separation and union of the Three Yang Meridians: Taiyang is Kai (Opening), Yangming is He (Closing), and Shaoyang is Shu (Pivot). (This summarizes the Three Yang. Taiyang as Opening means Yang Qi emanates outward, serving as the exterior of the Three Yang. Yangming as Closing means Yang Qi is stored inward, serving as the interior of the Three Yang. Shaoyang as Pivot means Yang Qi exists between exterior and interior, capable of exiting and entering, like a pivot mechanism. However, Kai, He, and Shu have distinctions of upper, middle, and lower, similar to the concepts of emerging and not emerging from the earth mentioned earlier, harmonizing with the Qi of Heaven and Earth.) These three meridians must not lose connection with each other. Their pulse should be firm and not floating excessively; this is called "One Yang." ("Three meridians" refers to the Yang meridians. Yang belongs to the Yang category and must not be disconnected. Regarding their pulse: although the Three Yang have distinct characteristics, Yang pulses tend to float. If purely floating, it indicates disease. Therefore, the pulse should only be firm to the touch, reflecting the harmonious image of Yang, without being excessively floating. This is the way the Three Yang unite, hence called "One Yang." This describes the separation and union of the Three Yang pulses.)
Huangdi said: I wish to hear about the Three Yin.
Qibo said: The exterior is Yang, the interior is Yin. Therefore, the middle is also Yin. (Exterior is Yang, referring to the surface. Interior is Yin, referring to the deep interior. Thus, the middle is also Yin, collectively referring to the interior-associated Three Yin as described below.) The Chong Mai is located inferiorly, named Taiyin. Taiyin originates at Yinbai (SP1), named Yin within Yin. (The Chong Mai is inferiorly located, named Taiyin, because Taiyin resides above the Chong Mai. Earlier it was stated that below Guangming is Taiyin; Guangming refers to the Heart, while Chong Mai relates to the Kidney. Roughly, the Heart, Spleen, and Kidney are positioned South, Center, and North respectively. Whenever Three Yang and Three Yin mention Chong Mai first, it is because Chong Mai is the Sea of the Twelve Meridians, used here to establish the outline. Taiyin originates at the big toe, thus rooted at Yinbai. Because Taiyin resides in a Yin sector, it is called Yin within Yin. The meanings of separation and union of the Three Yin interior/exterior below follow the pattern of the Three Yang. Subsequent texts adhere to this.)
Posterior to Taiyin is named Shaoyin. Shaoyin originates at Yongquan (KI1), named Lesser Yin within Yin. (Below and behind the Spleen is the position of the Kidney, so posterior to Taiyin is named Shaoyin. The Shaoyin meridian begins below the little toe, slanting toward the sole of the foot, thus rooted at Yongquan acupoint. The Kidney inherently belongs to Shaoyin and resides in a Yin sector, thus being Lesser Yin within Yin.)
Anterior to Shaoyin is named Jueyin. Jueyin originates at Dadun (LR1). It is the extreme of Yin and the extinction of Yang, named Extreme Yin of Yin. (Above and anterior to the Kidney is the position of the Liver, hence anterior to Shaoyin is named Jueyin. Jueyin originates at the big toe, thus rooted at Dadun. "Jue" means exhaustion/end; "Jue" also means end. This is the meridian of extreme Yin, hence called "Extreme Yang of Yin" and "Extreme Yin of Yin.")
Therefore, regarding the separation and union of the Three Yin Meridians: Taiyin is Kai (Opening), Jueyin is He (Closing), and Shaoyin is Shu (Pivot). (This summarizes the Three Yin, also involving interior/exterior distinctions. Taiyin as Opening resides in the superficial layer of Yin. Jueyin as Closing resides in the deep layer of Yin. Shaoyin as Pivot resides in the middle of Yin. Opening governs exit, Closing governs entry, and Pivot governs the space between entry and exit. This is consistent with the meaning of the Three Yang.) These three meridians must not lose connection with each other. Their pulse should be deep and firm without sinking excessively; this is called "One Yin." (All three meridians are Yin; Yin pulses are typically deep. They must not be disconnected. If excessively deep/sunken, it indicates disease. Therefore, the pulse should only be deep and firm with spirit, embodying the harmonious state of Yin pulses. This is the way the Three Yin unite, hence named "One Yin." This describes the separation and union of the Three Yin pulses.)
Yin and Yang Qi move continuously (*chong chong*), accumulating and transmitting to complete one cycle. Qi resides in the interior, Form stands in the exterior, thereby mutually completing each other. ("Chong chong" is alternatively written as "chong chong," describing the ceaseless movement of Yin and Yang Qi. "Accumulating and transmitting to complete one cycle" means the meridians circulate and accumulate, completing one cycle through fifty circuits day and night. Form is formed by Qi, and Qi gathers around Form. Thus, Qi operates in the interior, while Form stands in the exterior, interacting and supporting each other. This is the way Yin-Yang, interior-exterior, and separation-union mutually complete. Note: This chapter discusses only the Yin and Yang of the Foot meridians, omitting the Hand meridians. Why? Looking at the earlier text: "Heaven covers, Earth bears... those not out of earth are Yin within Yin; those out of earth are Yang within Yin." This suggests that the Qi of all things rises from the Earth. In humans, the waist above is Heaven, the waist below is Earth. Discussing the Foot meridians encompasses the entire body's meridian Qi, including the Hand meridians within them, hence there is no need to speak of the Hand meridians separately. Since the Feet are Yin, in the Three Yang meridians we say "Yang within Yin," and in the Three Yin meridians we say "Yin within Yin." Then, the Hand meridians also have separation and union: in Hand Yang meridians, it should be "Yang within Yang"; in Hand Yin meridians, it should be "Yang within Yin." This can be inferred analogously. The rationale for speaking of Feet but not Hands is detailed in Disease Category 39, which should be cross-referenced.)