少阴一经。兼水火二气。寒热杂居。故为病不可捉摹。其寒也症类太阴。其热也症似太阳。故仲景以微细之病脉。
欲寐之病情为提纲。立法于象外。使人求法于病中。凡症之寒热之真假。仿此义以推之。其阴阳虚实见矣。五经提纲。
皆是邪气盛则实。惟少阴提纲。是指正气夺则虚者。以少阴为人身之本也。然邪气之盛。亦因正气之虚。故五经皆有可
温可补症。正气之夺。亦因邪气之盛。故少阴亦有汗吐下症。要知邪气盛。而正气已虚者。固本即以逐邪。正不甚虚。
而邪气实者。逐邪正所以护正。此大法也。
少阳为阳枢。少阴为阴枢。弦为木象。弦而细者。是阳之少也。微为水象。微而细者。是阴之少也。此脉气之相似。
卫气行阳则寤。行阴则寐。其行阳二十五度。常从足少阴之分间行脏腑。少阴病。则枢机不利。故欲寐也。与少阳喜呕
者同。呕者主出。阳主外也。寐者主入。阴主内也。喜呕是不得呕。欲寐是不得寐。皆在病患意中。得枢机之象如此。
少阴脉微。不可发汗。亡阳故也。脉细沉数。病为在里。不可发汗。然可汗之机。亦见于此。夫微为无阳。数则有
复阳矣。须审其病为在里而禁汗。不得拘沉为在里而不发汗也。发汗脉沉者。是病为在表。以无里症。故可发汗。若脉
浮而迟。表热里寒。下利清谷。是迟而无阳。病为在里。又不得以浮为在表。而发汗矣。要知阴中有阳。沉亦可汗。阳
中有阴。浮亦当温。若八九日。一身手足本热。是自里达表。阳盛阴虚。法当滋阴。又与二三日无里症者不侔。
太阴是阳明之里。阳明不恶寒。故太阴虽吐利腹痛。而无恶寒症。少阴是太阳之里。太阳恶寒。故少阴吐利必恶寒。
阴从阳也。太阴手足温者必暴烦下利而自愈。是太阴藉胃脘之阳。少阴吐利。亦必手足温者可治。手足厥者不治。是下
焦
之虚寒。既侵迫于中宫。而胃脘之阳。仍得敷于四末。始知先天之元阳。仍赖后天之胃气培植也。
太阳是少阴之标。太阴是少阴之本。少阴阴虚。则移热于膀胱。故一身手足尽热而便血。从标也。少阴阳虚。则移
寒于脾而吐利。从本也。
少阴传阳。症有二。六七日腹胀不大便者。是传阳明。脏气实则还之腑也。八九日一身手足尽热者。是传太阳。阴
出之阳。下利极而上也。
热在膀胱而便血。亦脏病传腑。此阴乘阳也。然气病而伤血。又阳乘阴也。亦见少阴中枢之象。此是自阴转阳。与
太阳热结膀胱。血自下者。见症同而病因异。少阴病脉紧。至七八日。自下利。脉暴微。手足反温。脉紧反去者。虽烦
利必自愈。此亦是脾家实。露出太阳底板。故得与太阴。七八日暴烦下利自止同。盖少阴来复之。阳微。则转属太阴而
秽腐自去。盛则转属阳明而糟粕不传。郁则内实而入阳明大府广肠之区。横则外达而遍太阳内外盛血之部。要知紧脉转
微。是复少阴本脉。故转太阴而自解。脉沉细数。是兼阳脉。故入阳经而为患。然热虽甚不死。亦阴自阳则解之变局也。
六经皆有烦躁。而少阴更甚者。以其阴之虚也。盖阳盛则烦。阴极则躁。烦属气。躁属形。烦发于内。躁见于外。是形
从气动也。先躁而后烦。是气为形役也。不躁而时自烦。是阳和渐回。故可治。不烦而躁。是五脏之阳已竭。惟魄独居。
故死。故少阴以烦为生机。躁为死兆。
伤寒以阳为主。不特阴症见阳脉者生。亦阴病见阳症者可治也。凡蜷卧四逆。吐利交作。纯阴无阳之症。全赖一阳
来复。故反烦者可治。手足反温者。反发热者不死。
太阳少阴。皆有身痛骨节痛之表。水气为患之里。太阳则脉浮紧而身发热。用麻黄汤发汗。是振营卫之阳以和阴也。
少阴之脉沉而手足寒。用附子汤温补。是扶坎中之阳以配阴也。太阳之水属上焦。小青龙汗而发之。阳水当从外散也。
少阴之水属下焦。真武汤温而利之。阴水当从下泄也。阴阳俱紧。与太阳伤寒相似。夫紧脉为寒。当属少阴。然病发于
阴不当有汗。反汗出者。阴极似阳。阳虚不能藏精所致也。亡阳之前。已先亡阴矣。阳无所根据。故咽痛呕吐。见阳虚
之不归。阴不能藏。故下利不止。见真阴之欲脱也。则附子汤。用三白以滋阴。参附以回阳。为少阴反本还元之剂。
肾主五液。入以为汗。少阴受病。液不上升。所以阴不得有汗。仲景治少阴之表。于麻黄细辛中加附子。是升阳液
而为汗也。若真阴为邪热所逼。则水随火越。故反汗出。仲景治少阴之里。附子汤中任人参。是补肾液而止汗也。脉阴
阳俱紧。口中气出条。是少阴经文。王氏集之脉法中。故诸家议论不一。夫少阴脉络。肺主鼻。故鼻中涕出。少阴脉络
舌本。故舌上苔滑。少阴大络。注诸络以温足胫。故足冷。此症不名亡阳者。因不汗出。内不吐利也。口中气出。唇口
燥干。鼻中涕出。此为内热。阴阳脉紧。舌上苔滑。蜷卧足冷。又是内寒。此少阴为枢。故见寒热相持之症。而口舌唇
鼻之半表半里。恰与少阳之口苦。咽干。目眩。相应也。勿妄治者。恐阴阳相持。苟清火温补等法。用之不当。宁静
以待之。至七日来复。微发热。手足温。是阴得阳之解也。故八日以上。反大发热。再加吐利。即是亡阳。若其人反加
微寒。寒甚于表。上焦应之。必欲呕矣。若加腹痛。是寒甚于里。中焦受之。必欲利矣。当此阴盛。急当扶阳。庶不为
假热所惑而妄治。
但欲寐。即是不得眠。然但欲寐是病情。乃问而知之。不得眠是病形。可望而知之。欲寐是阴虚。不眠是烦躁。故
治法不同。
三阳惟少阳无承气症。三阴惟少阴有承气症。少阳为阳枢。阳稍虚。便入于阴。故不得妄下以虚其元阳。少阴为阴
枢。阳有余。便伤其阴。故当急下以存其真阴。且少阳属木。惟畏其克土。故无下症。少阴主水。更畏有土制。故当急
下。盖真阴不可虚。强阳不可从也。
少阴病。用大承气急下者。有三病症。得病三二日。热淫于内。肾水不支。因转属阳明。胃火上炎。故口燥咽干也。
急下之。谷气下流。津液得生矣。得病六七日。当解不解。津液枯涸。因转属阳明。故腹胀不大便。所谓已入于腑者。
下之则胀已。宜于急下者。六七日来阴虚已极。恐土实于中。心肾不交耳。若自利纯清水。心下痛。口燥舌干者。是土
燥火炎。脾气不濡。胃气反浓。水去而谷不去。故宜于急下。
少阴为性命之枢。少阴病。是死生关。故六经中。独于少阴历言死症。然少阴中风始得时。尚有发热脉沉可证。若
初受伤寒。其机甚微。脉细微。但欲寐。口中和。背恶寒。人已皆不觉其为病也。若身体疼。手足寒。骨节痛。脉浮者。
此表中阳虚症。心中烦。不得卧。此里之阴虚症也。若下利咽痛胸满心烦。与口中气出。唇口燥干。鼻中涕出。蜷卧足
冷。舌上苔滑者。此少阴半表半里。阴阳驳杂之症也。
脉阴阳俱紧。反汗出。而咽痛吐利者。此阴极似阳。肾阳不归。为亡阳症也。若至八九日。一身尽热者。是寒极生
热。肾阳郁极。而胜复太过也。其腹痛下利。小便不利者。有水火之分。若四肢沉重疼痛。为有水气。是阳虚而不胜阴
也。若便脓血。与泄利下重者。此为火。此阳邪陷入阴中也。下利清谷。里寒外热。手足厥逆。脉微欲绝。身反不恶寒。
其人面赤者。是下虚而极阳也。吐利兼作。手足逆冷。烦躁欲死者。是阴极而发躁也。岐伯曰。阴病治阳。阳病治阴。
定其中外。各守其乡。此即仲景治少阴之大法也。
同是恶寒蜷卧。利止手足温者可治。利不止。手足逆冷者不治。时自烦欲去衣被者可治。不烦而躁。四逆而脉不至
者死。同是吐利。手足不逆冷。反发热者不死。烦躁四逆者死。同是呕吐。汗出大便数少者可治。自利烦躁不得卧者死。
盖阴阳互为其根。阴中无阳则死。独阴不生故也。
少阴这一经，兼有水和火两种气机，寒证和热证混杂出现，所以病症难以捉摸。它的寒证表现类似太阴病，热证表现类似太阳病。因此，张仲景以脉象微细、精神萎靡想睡觉作为提纲，在表象之外确立法则，让人从具体的病症中去探寻治疗之法。凡是辨别寒热真假的问题，都可以依据这个义理来推演，这样阴阳虚实的情况就清楚了。其他四经的提纲，都是讲“邪气盛则实”，只有少阴病的提纲，是指“正气夺则虚”。因为少阴是人体的根本。然而，邪气的亢盛，也是因为正气的虚弱；所以五经都有可以温补的证候。正气的亏损，也是因为邪气的强盛；所以少阴病也有可以用汗法、吐法、下法治疗的证候。要知道，当邪气亢盛而正气已经虚弱时，固护根本也就是为了驱逐邪气；当正气不是很虚弱而邪气实证明显时，驱逐邪气正是为了保护正气。这是大的治疗原则。
少阳是阳气的枢纽，少阴是阴气的枢纽。“弦”脉属木象，弦而细，说明阳气不足。“微”脉属水象，微而细，说明阴气不足。这是脉气上的相似之处。卫气行于阳分人就清醒，行于阴分人就入睡。卫气行于阳分二十五周次，经常从足少阴肾经的分野运行到脏腑。患少阴病时，枢机运转不利，所以会出现想睡觉的症状。这与少阳病喜欢呕吐是一样的道理。呕吐主外出，阳主外；睡眠主内入，阴主内。喜欢呕吐是“想呕却呕不出来”，想睡觉是“想睡却睡不着”，这都是患者主观意识中的感受，体现了枢机失调的现象。
少阴病脉象微细，不可发汗，因为会耗亡阳气。如果脉象细沉数，说明病在里，不可发汗。然而，可汗的机理也蕴含其中。脉微表示无阳，但数脉则表示可能有阳气回复。必须仔细审查病是否在里从而禁止发汗，不能拘泥于沉脉主里就不发汗。如果发汗后脉象仍沉，说明病仍在表，因为没有里证，所以可以发汗。如果脉浮而迟，表现为表热里寒，腹泻完谷不化，这是迟脉表示无阳，病在里，又不能因为脉浮就在表而发汗了。要知道，阴中可以有阳，沉脉也可以发汗；阳中可以有阴，浮脉也应当温补。如果患病八九天，全身和手足原本发热，这是阳气从里达表，属于阳盛阴虚，治法应当滋阴，这又不同于患病两三天没有里证的情况。
太阴是阳明的里层，阳明不怕冷，所以太阴即使有呕吐、腹泻、腹痛，也没有怕冷的症状。少阴是太阳的里层，太阳怕冷，所以少阴出现呕吐、腹泻一定伴有怕冷。这是因为阴依附于阳。太阴病手足温暖的，一定会突然烦躁并腹泻，然后自愈，这是太阴借助了胃脘的阳气。少阴病呕吐腹泻，如果手足温暖的是可治的，手足厥冷的是不治的。这说明下焦的虚寒已经侵迫到中焦脾胃，而胃脘的阳气仍能布散到四肢末端，这才知道先天的元阳，仍然依赖后天的胃气来培植。
太阳是少阴的标，太阴是少阴的本。少阴阴虚，则热转移到膀胱，所以全身和手足都发热并且便血，这是从标论治。少阴阳虚，则寒转移到脾脏导致呕吐腹泻，这是从本论治。
少阴病传变为阳经病，有两种情况。六七天腹胀不大便的，是传入阳明，脏气充实转而归于腑。八九天全身和手足都发热的，是传入太阳，阴出转阳，由下利极而上行。
热在膀胱导致便血，也是脏病传腑，这是阴乘阳。但是气病伤及血分，又是阳乘阴。这也体现了少阴中枢的现象。这是从阴转阳，与太阳病热结膀胱、血液自行流出的情况，症状相同但病因不同。少阴病脉紧，到了七八天，自行腹泻，脉象突然变微，手足反而温暖，脉紧反而消失，虽然烦躁腹泻但必定自愈。这也是脾家实，显露出太阳的底子，所以能与太阴病七八天暴烦下利自止相类比。大概少阴阳气来复，脉微，则转属太阴而秽浊腐败之物自然去除；脉盛，则转属阳明而糟粕不传；郁结则内实而入阳明大肠广肠区域；横向发展则外达遍涉太阳内外盛血的部位。要知道紧脉转微，是恢复少阴的本脉，所以转属太阴而病解。脉沉细数，是兼有阳脉，所以进入阳经成为病患。然而热势虽重也不致死，这也是阴从阳解的一种变局。
六经都有烦躁，但少阴病更严重，因为其阴气虚弱。一般来说，阳盛则烦，阴极则躁。烦属于气，躁属于形。烦发于内，躁见于外，是形体跟随气动。先躁后烦，是气被形体所役使。不躁而时常自己烦躁，是阳气逐渐回复，所以可治。不烦而躁，是五脏阳气已竭，只有魄独居，所以死。因此少阴病以烦为生机，躁为死兆。
伤寒以阳气为主，不仅阴症见阳脉者生，阴病见阳症也可治。凡是蜷卧、四肢逆冷、呕吐腹泻交作，纯阴无阳的病症，全靠一阳来复。所以反见烦躁的可治，手足反温暖的，反发热的不死。
太阳和少阴，都有身痛骨节痛的表证，以及水气为患的里证。太阳病脉浮紧且身发热，用麻黄汤发汗，这是振奋营卫之阳以调和阴。少阴病脉沉且手足寒冷，用附子汤温补，这是扶持坎中之阳以配合阴。太阳的水气属于上焦，用小青龙汤发汗发散，阳水应当从外表消散。少阴的水气属于下焦，用真武汤温阳利水，阴水应当从下排泄。阴阳俱紧，与太阳伤寒相似。紧脉主寒，当属少阴。但是病发于阴不应当有汗，反而汗出的，是阴极似阳，阳虚不能藏精所致。在亡阳之前，已经先亡阴了。阳无所依，所以咽痛呕吐，见到阳虚不归；阴不能藏，所以腹泻不止，见到真阴欲脱。此时用附子汤，用三白（白芍、白术、茯苓）滋阴，人参附子回阳，是少阴病反本还元的方剂。
肾主管五液，进入体内化为汗。少阴受病，津液不能上升，所以阴证不应该有汗。张仲景治疗少阴表证，在麻黄细辛中加入附子，是升发阳气津液而为汗。如果真阴被邪热逼迫，则水随火越，所以反而汗出。张仲景治疗少阴里证，在附子汤中重用参附，是补肾液而止汗。脉阴阳俱紧，口中气息微弱，这是少阴经文，王叔和收集在脉法中，所以各家议论不一。少阴脉络联系肺和鼻，所以鼻中流涕；少阴脉络联系舌根，所以舌上苔滑；少阴大络注入诸络以温养足胫，所以脚冷。此症不称为亡阳，是因为没有汗出，内部没有呕吐腹泻。口中气息微弱，唇口干燥，鼻中流涕，这是内热。阴阳脉紧，舌上苔滑，蜷卧脚冷，这又是内寒。这是少阴作为枢纽，所以见到寒热相持的症状，而口舌唇鼻的半表半里状态，恰好与少阳的口苦、咽干、目眩相应。不要乱治，恐怕阴阳相持，如果清热、温补等方法使用不当，不如静待其变，等到七天阳气来复，微微发热，手足温暖，这是阴得到阳的化解。所以八日以上，反而大发热，再加呕吐腹泻，就是亡阳。如果病人反而加轻微恶寒，寒甚于表，上焦应之，必然想要呕吐。如果加上腹痛，是寒甚于里，中焦受之，必然想要腹泻。当此阴盛之时，急当扶阳，才不会因假热而迷惑妄治。
只想睡觉，就是不得安眠。但“但欲寐”是病情，是通过询问得知的；“不得眠”是病形，是通过观察得知的。欲寐是阴虚，不眠是烦躁，所以治法不同。
三阳经中只有少阳没有承气汤证，三阴经中只有少阴有承气汤证。少阳是阳枢，阳气稍虚就会陷入阴，所以不能妄用下法以免损伤元阳。少阴是阴枢，阳气有余就会损伤阴，所以应当急下以保存真阴。而且少阳属木，只害怕克伐脾土，所以没有下证。少阴主水，更害怕有土制约，所以应当急下。因为真阴不可虚，强阳不可顺从。
少阴病用大承气汤急下的，有三种证候。得病二三天，热邪淫溢于内，肾水支持不住，因而转属阳明，胃火上炎，所以口燥咽干。应当急下，使谷气下行，津液得以生成。得病六七天，应当解表而未解，津液枯涸，因而转属阳明，所以腹胀不大便。所谓病已入腑，下之则胀满消除。适宜急下的原因是，六七日来阴虚已极，恐怕土实于中，导致心肾不交。如果是自利清水，心下痛，口燥舌干，这是土燥火炎，脾气不濡润，胃气反而浓浊，水去而谷不去，所以适宜急下。
少阴是性命之枢纽，少阴病是生死之关，所以在六经中，唯独对少阴详细论述死症。然而少阴中风刚开始时，还有发热脉沉可以验证。如果初感伤寒，其机微细，脉细微，只想睡觉，口中平和，背部怕冷，人们都不觉得是病了。如果身体疼，手足寒，骨节痛，脉浮，这是表中阳虚症。心中烦，不得卧，这是里阴虚症。如果腹泻、咽痛、胸满、心烦，与口中气出、唇口干燥、鼻中流涕、蜷卧脚冷、舌上苔滑，这是少阴半表半里、阴阳驳杂的症候。
脉阴阳俱紧，反而汗出，且咽痛呕吐腹泻，这是阴极似阳，肾阳不归，为亡阳症。如果到了八九天，全身都发热，这是寒极生热，肾阳郁积至极而胜复太过。如果有腹痛腹泻、小便不利，是有水火的分别。如果四肢沉重疼痛，是有水气，是阳虚不胜阴。如果便脓血，以及泄利下重，这是火，是阳邪陷入阴中。如果腹泻完谷不化，里寒外热，手足厥逆，脉微欲绝，身体反而不怕冷，面色赤，这是下虚而极阳。呕吐腹泻兼作，手足逆冷，烦躁欲死，这是阴极而发躁。岐伯说：阴病治阳，阳病治阴，定其中外，各守其乡。这就是张仲景治疗少阴的大法。
同样是恶寒蜷卧，腹泻停止手足温暖的可以治，腹泻不止手足逆冷的不治。时常自己烦躁想去衣被的可以治，不烦躁而躁动，四肢逆冷且脉搏摸不到的死。同样是呕吐腹泻，手足不逆冷反而发热的不死，烦躁四肢逆冷的死。同样是呕吐，出汗大便次数少的可治，自利烦躁不得卧的死。因为阴阳互为其根，阴中无阳则死，独阴不生。
Shaoyin (Lesser Yin) channel encompasses both Water and Fire qi, with cold and heat syndromes mixed together; therefore, the manifestations are difficult to predict. Its cold-type symptoms resemble Taiyin (Greater Yin) disease, while its heat-type symptoms resemble Taiyang (Greater Yang) disease. Thus, Zhang Zhongjing established the diagnostic criteria based on a pulse that is faint and fine (Wei Xi), and a mental state of drowsiness (Yu Mei), setting principles beyond mere appearances to guide practitioners to seek treatment methods within the specific pathology. By applying this logic to distinguish true from false cold and heat, one can clarify the states of Yin/Yang and Deficiency/Excess. The diagnostic outlines for the other four channels all describe "Excess due to pathogenic Qi flourishing," whereas the Shaoyin outline describes "Deficiency due to Zheng Qi (Upright Qi) depletion," because Shaoyin is the root of the human body. However, pathogenic excess often stems from Zheng deficiency, hence all channels may have indications for warming and tonifying. Conversely, Zheng depletion often results from pathogenic excess, so Shaoyin disease also has indications for sweating, vomiting, and purging therapies. It must be understood that when pathogens are excessive and Zheng is already deficient, securing the root aids in expelling pathogens; when Zheng is not severely deficient but pathogens are excessive, expelling pathogens protects Zheng. This is a major principle.
Shaoyang (Lesser Yang) is the pivot of Yang, and Shaoyin is the pivot of Yin. A Wiry (Xian) pulse corresponds to Wood; Wiry yet fine indicates insufficient Yang. A Faint (Wei) pulse corresponds to Water; Faint yet fine indicates insufficient Yin. These are similarities in pulse quality. Wei Qi (Defensive Qi) moves through Yang during wakefulness and through Yin during sleep. It circulates through Yang twenty-five times, often passing through the divisions of Foot Shaoyin Kidney to reach the Zang-Fu organs. In Shaoyin disease, the pivot mechanism fails, leading to drowsiness. This parallels Shaoyang disease's tendency toward vomiting. Vomiting represents outward movement (Yang/External); sleep represents inward entry (Yin/Internal). "Tendency to vomit" implies an inability to vomit effectively; "drowsiness" implies an inability to stay awake. Both reflect the patient's subjective experience of pivot dysfunction.
In Shaoyin disease, if the pulse is faint, sweating should not be induced, as it would cause Yang collapse. If the pulse is fine, deep, and rapid, the disease is interior, and sweating is contraindicated. However, the potential for sweating exists here. A faint pulse suggests absence of Yang, but a rapid pulse may indicate Yang recovery. One must carefully determine if the disease is interior to forbid sweating, rather than rigidly adhering to the rule that a deep pulse always indicates interior disease precluding sweating. If sweating is performed and the pulse remains deep, the disease is still exterior, and since there are no interior signs, sweating is permissible. If the pulse is floating and slow, indicating exterior heat and interior cold, accompanied by diarrhea with undigested food, the slow pulse indicates absence of Yang and interior disease; one must not sweat simply because the pulse is floating. One must know that Yang resides within Yin, so even a deep pulse may allow sweating; Yin resides within Yang, so even a floating pulse may require warming. If after eight or nine days, the whole body and hands/feet become hot, this indicates Yang moving from interior to exterior, representing Yang excess and Yin deficiency, requiring Yin-nourishing methods. This differs from cases at two or three days without interior signs.
Taiyin is the interior of Yangming. Since Yangming does not fear cold, Taiyin, despite having vomiting, diarrhea, and abdominal pain, lacks aversion to cold. Shaoyin is the interior of Taiyang. Since Taiyang fears cold, Shaoyin vomiting and diarrhea are invariably accompanied by aversion to cold, as Yin follows Yang. In Taiyin, if hands and feet are warm, sudden irritability followed by diarrhea leads to self-healing, utilizing the Yang of the stomach. In Shaoyin vomiting/diarrhea, warmth of hands and feet indicates treatability, while cold extremities indicate untreatability. This shows that lower Jiao deficiency-cold invading the middle Jiao is survivable only if stomach Yang still reaches the limbs, proving that先天 Yuan Yang (Pre-heaven Primordial Yang) relies on 后天 Wei Qi (Post-heaven Stomach Qi) for cultivation.
Taiyang is the Biao (Manifestation) of Shaoyin; Taiyin is the Ben (Root) of Shaoyin. Shaoyin Yin deficiency transfers heat to the Bladder, causing whole-body/hand-foot heat and hematochezia (following Biao). Shaoyin Yang deficiency transfers cold to the Spleen, causing vomiting/diarrhea (following Ben).
Transmission from Shaoyin to Yang channels occurs in two ways: Abdominal distension and constipation after 6-7 days indicates transmission to Yangming (Zang excess transferring to Fu). Whole-body/hand-foot heat after 8-9 days indicates transmission to Taiyang (Yin emerging to Yang, rising from severe diarrhea).
Heat in the Bladder causing blood in stool is Zang-to-Fu transmission, Yin attacking Yang. Qi pathology affecting Blood is Yang attacking Yin. This reflects Shaoyin pivot dynamics. This transition from Yin to Yang shares symptoms with Taiyang Heat Binding in the Bladder but differs in etiology. In Shaoyin disease, a tight pulse lasting 7-8 days with spontaneous diarrhea, sudden faintness of pulse, warming of extremities, and disappearance of tightness, despite irritability and diarrhea, indicates self-healing. This resembles Spleen Fullness in Taiyin. Generally, Shaoyin Yang recovery with a faint pulse shifts to Taiyin, clearing turbidity; strong pulse shifts to Yangming, retaining waste; stagnation leads to interior fullness in Large Intestine; lateral spread affects Taiyang blood regions. Tight-to-faint pulse returns to Shaoyin's original state, resolving via Taiyin. Deep/fine/rapid pulses involve Yang channels, causing illness. Though severe heat is not fatal, it represents a variation of Yin resolving via Yang.
Irritability (Fan) and restlessness (Zao) occur in all six channels but are worse in Shaoyin due to Yin deficiency. Yang excess causes Fan; Yin extreme causes Zao. Fan relates to Qi (internal); Zao relates to Form (external). Zao then Fan means Qi is enslaved by Form. Spontaneous Fan without Zao indicates returning Yang (treatable). Fanless Zao indicates exhaustion of Zang Yang (fatal). Thus, Fan is life, Zao is death in Shaoyin.
Shanghan prioritizes Yang. Yin syndromes with Yang pulses survive; Yin diseases with Yang symptoms are treatable. For curling up, cold limbs, vomiting/diarrhea (Pure Yin/No Yang), reliance on one Yang returning is key. Reverse irritability is treatable; reverse warming of limbs/heat generation is non-fatal.
Both Taiyang and Shaoyin present exterior body/joint pain and interior water retention. Taiyang: Floating/Tight pulse, fever → Ma Huang Tang (stimulate Ying-Wei Yang to harmonize Yin). Shaoyin: Deep pulse, cold limbs → Fu Zi Tang (support Kan Yang to match Yin). Taiyang water is Upper Jiao → Xiao Qing Long Tang (sweat to disperse Yang water). Shaoyin water is Lower Jiao → Zhen Wu Tang (warmth to drain Yin water).
Pulse Yin/Yang both tight resembles Taiyang Shanghan. Tight pulse indicates Cold, fitting Shaoyin. But Yin onset shouldn't sweat; spontaneous sweating indicates Yin extreme mimicking Yang, or Yang deficiency failing to store Essence. Pre-Yang collapse involves Yin loss. Yang unanchored causes sore throat/vomiting; Yin unable to store causes persistent diarrhea. Fu Zi Tang uses Bai Shao/Bai Zhu/Fu Ling to nourish Yin, Ren Shen/Fu Zi to restore Yang, acting as a return-to-root formula.
Kidney governs fluids/sweat. Shaoyin disease prevents fluid ascent, so Yin syndromes shouldn't sweat. Zhang Zhongjing treats Shaoyin exterior with Ma Huang/Xi Xin + Fu Zi to raise Yang/fluids into sweat. If True Yin is forced by heat, water follows fire → spontaneous sweat. Zhang treats Shaoyin interior with Fu Zi Tang + Ren Shen to tonify Kidney fluid and stop sweat.
"Tight pulse Yin/Yang, weak breath" is Shaoyin text collected by Wang Shuhe, causing debate. Shaoyin connects to Lung/Nose → runny nose. Connects to Tongue base → slippery coating. Connects to legs → cold feet. Not called Yang collapse because no sweat/vomit/diarrhea internally. Weak breath, dry lips/nose/runny nose = Internal Heat. Tight pulse, slippery coating, curling/cold feet = Internal Cold. Shaoyin pivot causes cold-heat standoff. Oral/nasal half-exterior/half-interior mirrors Shaoyang's bitter taste, dry throat, vertigo. Do not treat rashly; wait for Day 7 Yang recovery (mild heat, warm limbs). After Day 8, high fever + vomiting/diarrhea = Yang collapse. Mild chills = Exterior cold affecting Upper Jiao (vomiting). Abdominal pain = Interior cold affecting Middle Jiao (diarrhea). In Yin excess, urgently support Yang to avoid being misled by false heat.
"Drowsiness" (Dan Yu Mei) is inability to sleep peacefully. It is a symptom known by inquiry. "Insomnia" (Bu De Mian) is a sign observed visually. Drowsiness indicates Yin deficiency; insomnia indicates irritability. Treatments differ.
Among Three Yang, only Shaoyang lacks Cheng Qi indications. Among Three Yin, only Shaoyin has Cheng Qi indications. Shaoyang is Yang pivot; slight Yang deficiency enters Yin, so do not purge to damage Yuan Yang. Shaoyin is Yin pivot; Yang excess damages Yin, so urgent purging preserves True Yin. Shaoyang (Wood) fears Earth suppression, so no purge. Shaoyin (Water) fears Earth control, so urgent purge is needed. True Yin must not be deficient; Strong Yang must not be followed.
Three indications for Da Cheng Qi Tang in Shaoyin:
1. Days 2-3: Heat rampant inside, Kidney Water failing, transferring to Yangming, Stomach Fire flaring → dry mouth/throat. Urgent purge allows grain Qi to flow down, generating fluids.
2. Days 6-7: Failure to resolve, fluids dried, transferring to Yangming → abdominal distension/constipation. Disease entered Fu, purge resolves distension. Urgent purge needed due to extreme Yin deficiency and risk of Heart-Kidney non-interaction.
3. Clear watery diarrhea, epigastric pain, dry mouth/tongue: Dry Earth/Fire flare, Spleen not moistening, Stomach thick/concentrated. Water gone, grain remains. Urgent purge required.
Shaoyin is the pivot of life/death. Only Shaoyin details fatal cases. Early Shaoyin Wind Strike has fever/deep pulse. Initial Shanghan is subtle: fine/faint pulse, drowsiness, neutral mouth, back aversion to cold, unnoticed. Body pain/cold limbs/joint pain/floating pulse = Exterior Yang deficiency. Irritability/insomnia = Interior Yin deficiency. Diarrhea/sore throat/chest fullness/irritability + weak breath/dry lips/runny nose/curling/cold feet/slipping coating = Shaoyin Half-Exterior/Half-Interior, mixed Yin/Yang.
Tight pulse Yin/Yang + sweat + sore throat/vomit/diarrhea = Yin extreme mimicking Yang, Kidney Yang departing, Yang collapse. Days 8-9 whole body heat = Cold extreme generating heat, Kidney Yang stagnant/rebounding excessively. Abdominal pain/diarrhea/urinary difficulty = Water/Fire distinction. Heavy/painful limbs = Water Qi (Yang deficiency cannot overcome Yin). Pus/blood in stool/heavy feeling = Fire (Yang pathogen sinking into Yin). Undigested diarrhea/interior cold/exterior heat/cold limbs/faint pulse/no aversion to cold/red face = Lower deficiency/Extreme Yang. Vomit/diarrhea/cold limbs/severe irritability = Yin extreme causing agitation. Qibo said: Treat Yang for Yin disease, Yin for Yang disease, stabilize center/periphery. This is Zhang Zhongjing's major Shaoyin method.
Same aversion to cold/curling: Diarrhea stops/warm limbs = Treatable. Diarrhea continues/cold limbs = Untreatable. Spontaneous irritability/removing clothes = Treatable. No irritability/restlessness/cold limbs/no pulse = Fatal. Same vomit/diarrhea: Limbs not cold/reverse heat = Non-fatal. Irritability/cold limbs = Fatal. Same vomiting: Sweat/frequent small stools = Treatable. Self-diarrhea/irritability/insomnia = Fatal. Yin/Yang are roots of each other; Yin without Yang dies; Pure Yin cannot generate life.