风寒二气，有阴阳之分，又相因为患。盖风中无寒，即是和风，一夹寒邪，中人而病，故得与伤寒相类，亦得
以伤寒名之。所以四时皆有风寒，而冬月为重也。伤寒中风，各有重轻，不在命名，而在见症。太阳篇言中风脉
症者二∶一曰太阳中风，阳浮而阴弱，阳浮者热自发，阴弱者汗自出，啬啬恶寒、淅淅恶风、翕翕发热、鼻鸣干
呕者，桂枝汤主之；一曰太阳中风，脉浮紧，发热恶寒，身疼痛，不汗出而烦躁者，大青龙汤主之。以二症相较，
阳浮见寒之轻，浮紧见寒之重；汗出见寒之轻，不汗出见寒之重；啬啬淅淅见风寒之轻，翕翕见发热之轻，发热
恶寒见寒热之俱重；鼻鸣见风之轻，身疼见风之重；自汗干呕，见烦之轻，不汗烦躁，见烦之重也。言伤寒脉症
者二∶一曰太阳病，或未发热，或已发热，必恶寒体痛呕恶，脉阴阳俱紧者，名曰伤寒；一曰伤寒脉浮，自汗出，
小便数，心烦微恶寒，脚挛急。以二症相较，微恶寒，见必恶寒之重，体痛，觉脚挛急之轻；自汗出、小便数、
心烦，见伤寒之轻，或未发热，见发热之轻，必先呕逆，见伤寒之重；脉浮见寒之轻，阴阳俱紧见寒之重。中风
伤寒，各有轻重如此。今人必以伤寒为重，中风为轻，但知分风寒之中、伤，而不辨风寒之轻重，于是有伤寒见
风、中风见寒之遁辞矣。夫风为阳邪，寒为阴邪，虽以皆于时气之感，而各不失其阴阳之性。故伤寒轻者，全似
中风，独脚挛急不似，盖腰以上为阳，而风伤于上也；中风重者，全似伤寒，而烦躁不似，盖寒邪呕而不烦，逆
而不躁也。 然阴阳互根，烦为阳邪，烦极致躁；躁为阴邪，
躁极致烦。故中风轻者烦轻，中风重者烦躁，伤寒重者躁烦，伤寒轻者微烦。微烦则恶寒亦微，是微阳足以胜微
寒，故脉浮不紧矣。如本论所云∶凡欲自解者，必当先烦，乃有汗而解。以脉浮不紧，故知汗出解也。若不待自
解而妄攻其表，所以亡阳，因阳微故耳。凡伤寒见烦，则寒气欲解。躁烦则阳为寒郁，而邪转盛。故伤寒一日，
若躁烦者，为欲传；六七日，躁烦者，为阳去入阴也。因病患所禀之阳气有不同，而受邪之部位、阴阳更不类，
故阳有多少，热有微甚。如太阳为先天之巨阳，其热发于营卫，故一身手足壮热。阳明乃太少两阳相合之阳，其
热发于肌肉，故蒸蒸发热。少阳为半表半里之阳，其热发于腠理，时开时阖，故往来寒热。此三阳发热之差别也。
太阴为至阴，无热可发，因为胃行津液，以灌四旁，故得主四肢，而热发于手足。所以太阴伤寒，手足自温，太
阴中风，四肢烦疼耳。少阴为封蛰之本，若少阴不藏，则坎阳无蔽。故有始受风寒而脉沉发热者，或始无表热，
八九日来，热入膀胱，致一身手足尽热者。厥阴当两阴交尽，一阳之初生，其伤寒也，有从阴而先厥后热者，有从
阳而先热后厥者，或阳进而热多厥少，或阳退而热少厥多，或阴阳和而厥与热相应者。是三阴发热之差别也。太
阳为父，多阳盛之病。如初服桂枝而反烦，解半日许而复烦，下之而脉仍浮、气上冲，与不汗出而躁烦，服药微
除而烦瞑发衄者，皆阳气重故也。少阴为雌，多亡阳之病。如下利清谷，手足厥逆，脉微欲绝，恶寒蜷卧，吐利
汗出，里寒外热，不烦而躁，皆亡阳故也。又《内经·病形篇》云∶“邪中于项，则下太阳，中于面，则下阳明，
中于颊，则下少阳，其中膺背两胁，亦中其经。”故本论太阳受邪，有中项中背之别，中项则头项强痛，中背则
背强KT KT 也。阳明有中面中膺之别，中面则目疼鼻干，中膺则胸中痞硬也。少阳有中颊中胁之别，中颊则口苦咽
干，中胁则胁下痞硬也。此岐伯中阳溜经之义。又云∶“邪中于阴，从臂 始，自经及脏，脏气实而不能容，则
邪还于府。”故本论三阴皆有自利症，是寒邪还府也；三阴皆有可下症，是热邪还府也。此岐伯中阴溜府之义。
六经之部位有高下，故受邪之日有远近。太阳为三阳，居表位最高，最易伤寒，故一日受；阳明为二阳而居前，
故二日受；少阳为一阳而居侧，故三日受；太阴为三阴，居阴位最高，故四日受；少阴为二阴，居阴位之中，故
五日受；厥阴为一阴，居三阴之尽，故六日受。此皆言见症之期，非六经以次相传之日也。《内经》曰∶
“气有高下，病有远近，适其至所。”即此意也。按本论传字之义，各各不同，必牵强为传经则谬。伤寒一日，
太阳受之，脉若静者为不传，是指热传本经，不是传阳明之经络。阳明无所复传，始虽恶寒，二日自止，是指寒
传本经，不是传少阳之经络。伤寒二三日，阳明少阳症不见者，为不传，皆指热传本经，不是二日传阳明，三日
传少阳之谓。太阳病至七日以上自愈者，以行其经尽故也。言七日当来复之辰，太阳一经之病当尽，非日传一经，
七日复传太阳之谓。若复传，不当曰尽，若日一经，不当曰行其经矣。若欲再作经，是太阳不罢而并病阳明。传
经不传，是使阳明之经不传太阳之热，非再传少阳之谓也。太阳与阳明少阳地位相近，故太阳阳盛而不罢，便转
属阳明，阳已衰而不罢，便转系少阳。若阳陷便转系太阴，阳虚则转入少阴，阳逆则转属厥阴矣。阳明万物所归，
故六经皆得转属。而阳明无所复传，是知太阳阳明无转属少阳之症。阳明太阴俱属于胃，胃实则太阴转属阳明，
胃虚则阳明转属太阴矣。少阴与二阴地位相近，受太阴之寒，则吐利清谷，受厥阴之热，则咽痛便血也。厥阴为
阴之尽，亦如阳明之无所复传，然阴出之阳，则热多厥少，阴极亡阳，则热少厥多，此即少阳往来寒热之变局也。
按本论云∶“太阳病，发热汗出，恶风脉缓者，为中风。”又云∶“太阳中风，脉浮紧，不汗出而烦躁。”又云∶
“阳明中风，脉弦浮大，不得汗。”合观之，不得以无汗为非中风矣。本论云∶“太阳病，或未发热，或已发热，
必恶寒体痛呕逆，脉阴阳俱紧者，名伤寒。”而未尝言无汗。又云∶“太阳病头痛发热，身疼腰痛，骨节疼痛，
恶风无汗而喘者，麻黄汤主之。”此不冠以伤寒，又不言恶寒。又云∶“伤寒脉浮，自汗出，微恶寒。”合观之，
又不得以有汗为非伤寒矣。人但据桂枝条之中风自汗，而不究伤寒亦有自汗出者。强以麻黄症之无汗为伤寒，而
不究中风最多无汗者。谓伤寒脉浮紧，中风脉浮缓，而不知伤寒亦有浮缓，中风亦有浮紧者。知三阳脉浮，三阴
脉沉，而不知三阴皆有浮脉，三阳亦有沉脉者。总是据一条之说，不理会全书耳。当知麻黄汤大青龙汤治中风之
重剂，桂枝汤葛根汤治中风之轻剂，伤寒可通用之，非主治伤寒之剂也。世皆推桂枝为中风主剂，而不敢以大青
龙为中风之剂者，是惑于中风见寒脉，伤寒见风脉之谬也。不敢以麻黄为中风之剂者，是泥于有汗为中风，无汗
为伤寒之谬也。风为阳邪，因四时之气而变迁，且一日亦具有四时之气，气运更有郁复
淫胜之不同，故有麻黄、桂枝、葛根、青龙等法。当知四时俱有中风，俱有伤寒，不得拘春伤于风，冬伤于寒之
一说矣。太阳经多中风方，如麻黄、桂枝，葛根、大青龙是也。少阴经多伤寒方，如麻黄附子细辛、真武、附子、
茱萸、白通、四逆、通脉等汤是也。中风诸方，可移治伤寒，伤寒诸方，不可移治中风者，寒可温而风不可以热
治也。风为阳邪，故中风者虽在少阴，每多阳症；寒为阴邪，故伤寒者虽在太阳，每多阴症。太阳经多中风症，
阳从阳也；少阴经多伤寒症，阴从阴也。夫风者，善行而数变，故脉症皆不可拘。自变者观之，其症或自汗鼻鸣，
或无汗而喘，或不汗出而烦躁，或下利呕逆，或渴欲饮水，或往来寒热，或口苦咽干，或短气腹满、鼻干嗜卧，
或目赤耳聋、胸满而烦，或四肢烦疼，种种不同；其脉或浮缓，或浮紧，或弦而浮大，或阳微阴涩，或阳微阴浮，
亦种种不同。自不变者观之，惟浮是中风之主脉，恶风是中风之定症。盖风脉变态不常，而浮为真体；风症变幻
多端，而恶风其真情也。仲景广设诸方，以曲尽其变耳。夫寒之伤人也有三∶早晚雾露，四时风雨，冬春霜雪，
此天之寒气也；幽居旷室，砖地石阶，大江深泽，邃谷高山，地之寒气也；好饮寒泉，喜食生冷，酷嗜瓜果，误
服冷药，人之寒气也。此义最浅，伤寒诸书莫之或及，而以冬寒春温时疫之三症掩之，何不求致病之因，而归时
令之变耶？夫寒固为冬气，三时岂必无寒？第寒有轻重，伤亦有轻重，不拘定于冬。温固为春气，而三时亦病温，
且温随时而发者多，因冬月伤寒而致者少，不可谓必然之道也。即冬时病温，亦因其人阴虚而发，岂冬时之暖气，
即有毒以伤人乎？若时行疫气，正天地温热之毒，如凉风一起，疫邪自散，岂遇寒而反重耶？疫与寒，如风牛马
之不相及，何得以寒冠时行之疫？若为暴寒所折而病，即是三时之伤寒，勿得妄以疫名之矣。谓三四月阳气尚弱，
为寒折而病热轻，五六月阳气已盛，为寒折而病热重，七八月阳气已衰，为寒折而病热微，此叔和无稽之说也。
夫病寒病热，当审其人阴阳之盛衰，不得拘天气之寒热。天气之寒热伤人，必因其人阴阳之多少，元气之虚实为
轻重，不全凭时令之阴阳为转移也。所以仲景制方，全以平脉辨症为急务，不拘于受病之因，不拘于发病之时为
施治。如夏月盛暑而伤寒吐利，多有用姜、附、吴萸而始效，隆冬严寒而病温，多有用石膏、硝、黄而热乃解者。
今谓麻桂二汤只宜于冬月之正伤寒，而三时不可轻用，其失岂不多乎？夫开口言伤寒，动手
反用寒凉克伐之剂，曷不于伤寒二字顾名思义耶？寒伤于表，法当温散；寒伤于里，法当温补。仲景治伤寒，只
有温散、温补二法。其清火、凉解、吐下等法，正为温暑时疫而设，所以治热，非以治寒，治热淫于内，非治寒
伤于表也。今伤寒家皆曰仲景治温治暑，必另有法治，今遗失而无。惟伤寒只有汗吐下三法，将温补正法，置之
不用，反曰治伤寒无补法。于是人伤于天地之寒者轻，伤于医师之法者重；死于饮食之内伤者少，死于寒药之内
伤者多耳。
风寒二气，有阴阳之分，又相互关联致病。风邪中若无寒邪夹杂，便是和风（平和之风），一旦夹带寒邪，侵袭人体而发病，所以症状与伤寒相似，也可以称之为伤寒。因此四季都有风寒之邪，但冬季最为严重。伤寒和中风，各有轻重之分，关键不在于名称，而在于临床表现。《伤寒论》太阳篇中提到中风脉症的有两处：一处说太阳中风，脉象阳浮阴弱，阳浮表示热自发，阴弱表示汗自出，伴有怕冷、怕风、发热、鼻鸣、干呕等症状，用桂枝汤主治；另一处说太阳中风，脉象浮紧，发热恶寒，身体疼痛，无汗且烦躁，用大青龙汤主治。比较这两种症状，阳浮显示寒邪较轻，浮紧显示寒邪较重；有汗显示寒邪较轻，无汗显示寒邪较重；啬啬淅淅（形容怕冷怕风的样子）显示风寒较轻，翕翕（形容发热温和的样子）显示发热较轻，发热恶寒并见显示寒热俱重；鼻鸣显示风邪较轻，身体疼痛显示风邪较重；自汗干呕显示烦扰较轻，无汗烦躁显示烦扰较重。提到伤寒脉症的也有两处：一处说太阳病，或者尚未发热，或者已经发热，必定恶寒、身体疼痛、呕吐恶心，脉象阴阳俱紧的，名叫伤寒；另一处说伤寒脉浮，自汗出，小便频数，心烦轻微恶寒，脚部拘挛急迫。比较这两种症状，轻微恶寒显示必定恶寒的程度更重，身体疼痛显示脚部拘挛急迫程度较轻；自汗出、小便频数、心烦显示伤寒较轻，或者尚未发热显示发热较轻，必须先出现呕吐逆乱显示伤寒较重；脉浮显示寒邪较轻，阴阳俱紧显示寒邪较重。中风和伤寒，各有如此轻重之分。现在的人一定认为伤寒为重，中风为轻，只知道区分风寒中的“中”和“伤”，却不辨别风寒的轻重，于是就有了“伤寒见风症、中风见寒症”这种推脱之辞了。风是阳邪，寒是阴邪，虽然都因时令之气感染，但各自不失其阴阳本性。所以轻度的伤寒，完全像中风，只有脚部拘挛急迫不像，因为腰以上属阳，风邪伤于上；重度的中风，完全像伤寒，只有烦躁不像，因为寒邪导致呕吐而不烦，逆乱而不躁。然而阴阳互根，烦属于阳邪，烦到极致则躁；躁属于阴邪，躁到极致则烦。所以中风轻者烦轻，中风重者烦躁，伤寒重者躁烦，伤寒轻者微烦。微烦则恶寒也轻微，这是微弱的阳气足以战胜微弱的寒邪，所以脉象浮而不紧。如本书所说：凡是想要自愈的，必定先出现烦，然后才有汗出而解。因为脉象浮而不紧，所以知道是汗出而解。如果不等待自愈而妄自攻表，就会导致亡阳，这是因为阳气微弱的原因。凡是伤寒见到烦，说明寒气将要解除。躁烦则是阳气被寒邪郁遏，而邪气反而强盛。所以伤寒第一天，如果躁烦，是病欲传变；六七天，如果躁烦，是阳气离去进入阴经。因为病人禀受的阳气有所不同，而受邪的部位、阴阳情况也不相同，所以阳气有多少，热势有微甚。如太阳经是先天巨阳，其热发于营卫，所以一身手足壮热。阳明经是太少两阳相合之阳，其热发于肌肉，所以蒸蒸发热。少阳经是半表半里之阳，其热发于腠理，时开时阖，所以往来寒热。这是三阳发热的差别。太阴经是至阴，没有热可发，因为胃行津液以灌溉四旁，所以主管四肢，而热发于手足。所以太阴伤寒，手足自然温暖，太阴中风，四肢烦疼。少阴经是封蛰之本，如果少阴不藏，则坎阳无蔽。所以有的开始受风寒而脉沉发热，或者开始没有表热，八九日后，热入膀胱，导致一身手足尽热。厥阴经当两阴交尽，一阳初生，其伤寒，有从阴而先厥后热的，有从阳而先热后厥的，或者阳进而热多厥少，或者阳退而热少厥多，或者阴阳调和而厥与热相应。这是三阴发热的差别。太阳经为父，多阳盛之病。如初服桂枝汤反而烦，过半天左右又烦，下之后脉仍浮、气上冲，以及无汗而躁烦，服药后症状稍减而烦闷嗜睡甚至鼻衄的，都是阳气重的缘故。少阴经为雌，多亡阳之病。如下利清谷，手足厥逆，脉微欲绝，恶寒蜷卧，吐利汗出，里寒外热，不烦而躁，都是亡阳的缘故。又《内经·病形篇》说：“邪中于项，则下太阳，中于面，则下阳明，中于颊，则下少阳，其中膺背两胁，亦中其经。”所以本书太阳经受邪，有中项和中背的区别，中项则头项强痛，中背则背强僵硬。阳明经有中面和中膺的区别，中面则目疼鼻干，中膺则胸中痞硬。少阳经有中颊和中胁的区别，中颊则口苦咽干，中胁则胁下痞硬。这是岐伯中阳溜经的道理。又说：“邪中于阴，从臂始，自经及脏，脏气实而不能容，则邪还于府。”所以本书三阴经都有自利症，是寒邪还于府；三阴经都有可下症，是热邪还于府。这是岐伯中阴溜府的道理。六经的部位有高下，所以受邪的日子有远近。太阳经为三阳，居表位最高，最容易受伤寒，所以一日受邪；阳明经为二阳而居前，所以二日受邪；少阳经为一阳而居侧，所以三日受邪；太阴经为三阴，居阴位最高，所以四日受邪；少阴经为二阴，居阴位之中，所以五日受邪；厥阴经为一阴，居三阴之尽，所以六日受邪。这都是说出现症状的时期，不是六经依次相传的日子。《内经》说：“气有高下，病有远近，适其至所。”就是这个意思。按本书“传”字的含义，各不相同，如果牵强地认为是传经就错了。伤寒第一天，太阳经受邪，脉若静者为不传，是指热传本经，不是传阳明之经络。阳明无所复传，开始虽恶寒，二日自止，是指寒传本经，不是传少阳之经络。伤寒二三日，阳明少阳症不见者，为不传，皆指热传本经，不是二日传阳明，三日传少阳的意思。太阳病至七日以上自愈者，是因为行其经尽的缘故。是说七日应当来复之时，太阳一经的病应当结束，不是日传一经，七日复传太阳的意思。如果再传，不当说“尽”，如果日传一经，不当说“行其经”。如果想再作经，是太阳不罢而并病阳明。传经不传，是使阳明之经不传太阳之热，不是再传少阳的意思。太阳与阳明少阳地位相近，所以太阳阳盛而不罢，便转属阳明，阳已衰而不罢，便转系少阳。若阳陷便转系太阴，阳虚则转入少阴，阳逆则转属厥阴。阳明万物所归，所以六经皆得转属。而阳明无所复传，是知道太阳阳明无转属少阳的症状。阳明太阴俱属于胃，胃实则太阴转属阳明，胃虚则阳明转属太阴。少阴与二阴地位相近，受太阴之寒，则吐利清谷，受厥阴之热，则咽痛便血。厥阴为阴之尽，也如同阳明之无所复传，然而阴出之阳，则热多厥少，阴极亡阳，则热少厥多，这就是少阳往来寒热的变局。按本书说：“太阳病，发热汗出，恶风脉缓者，为中风。”又说：“太阳中风，脉浮紧，不汗出而烦躁。”又说：“阳明中风，脉弦浮大，不得汗。”综合来看，不能因为没有汗就不是中风。本书说：“太阳病，或未发热，或已发热，必恶寒体痛呕逆，脉阴阳俱紧者，名伤寒。”而未尝说无汗。又说：“太阳病头痛发热，身疼腰痛，骨节疼痛，恶风无汗而喘者，麻黄汤主之。”这不冠以伤寒，又不言恶寒。又说：“伤寒脉浮，自汗出，微恶寒。”综合来看，又不能因为有汗就不是伤寒。人们只根据桂枝条的中风自汗，而不探究伤寒也有自汗出的情况。强行以麻黄症的无汗为伤寒，而不探究中风最多无汗的情况。谓伤寒脉浮紧，中风脉浮缓，而不知道伤寒也有浮缓，中风也有浮紧的情况。知三阳脉浮，三阴脉沉，而不知道三阴皆有浮脉，三阳亦有沉脉的情况。总是依据一条之说，不理会全书罢了。应当知道麻黄汤、大青龙汤是治中风的重剂，桂枝汤、葛根汤是治中风的轻剂，伤寒可通用，并非主治伤寒的方剂。世人都推崇桂枝汤为中风主剂，而不敢以大青龙汤为中风之剂，是惑于中风见寒脉，伤寒见风脉的错误观点。不敢以麻黄汤为中风之剂，是拘泥于有汗为中风，无汗为伤寒的错误观点。风为阳邪，因四时之气而变迁，且一日也具有四时之气，气运更有郁复淫胜的不同，所以有麻黄、桂枝、葛根、青龙等法。应当知道四季都有中风，都有伤寒，不能拘泥于春伤于风，冬伤于寒的说法。太阳经多中风方，如麻黄、桂枝，葛根、大青龙是也。少阴经多伤寒方，如麻黄附子细辛、真武、附子、茱萸、白通、四逆、通脉等汤是也。中风诸方，可移治伤寒，伤寒诸方，不可移治中风者，寒可温而风不可以热治也。风为阳邪，故中风者虽在少阴，每多阳症；寒为阴邪，故伤寒者虽在太阳，每多阴症。太阳经多中风症，阳从阳也；少阴经多伤寒症，阴从阴也。夫风者，善行而数变，故脉症皆不可拘。自变者观之，其症或自汗鼻鸣，或无汗而喘，或不汗出而烦躁，或下利呕逆，或渴欲饮水，或往来寒热，或口苦咽干，或短气腹满、鼻干嗜卧，或目赤耳聋、胸满而烦，或四肢烦疼，种种不同；其脉或浮缓，或浮紧，或弦而浮大，或阳微阴涩，或阳微阴浮，亦种种不同。自不变者观之，惟浮是中风之主脉，恶风是中风之定症。盖风脉变态不常，而浮为真体；风症变幻多端，而恶风其真情也。仲景广设诸方，以曲尽其变耳。夫寒之伤人也有三∶早晚雾露，四时风雨，冬春霜雪，此天之寒气也；幽居旷室，砖地石阶，大江深泽，邃谷高山，地之寒气也；好饮寒泉，喜食生冷，酷嗜瓜果，误服冷药，人之寒气也。此义最浅，伤寒诸书莫之或及，而以冬寒春温时疫之三症掩之，何不求致病之因，而归时令之变耶？夫寒固为冬气，三时岂必无寒？第寒有轻重，伤亦有轻重，不拘定于冬。温固为春气，而三时亦病温，且温随时而发者多，因冬月伤寒而致者少，不可谓必然之道也。即冬时病温，亦因其人阴虚而发，岂冬时之暖气，即有毒以伤人乎？若时行疫气，正天地温热之毒，如凉风一起，疫邪自散，岂遇寒而反重耶？疫与寒，如风牛马之不相及，何得以寒冠时行之疫？若为暴寒所折而病，即是三时之伤寒，勿得妄以疫名之矣。谓三四月阳气尚弱，为寒折而病热轻，五六月阳气已盛，为寒折而病热重，七八月阳气已衰，为寒折而病热微，此叔和无稽之说也。夫病寒病热，当审其人阴阳之盛衰，不得拘天气之寒热。天气之寒热伤人，必因其人阴阳之多少，元气之虚实为轻重，不全凭时令之阴阳为转移也。所以仲景制方，全以平脉辨症为急务，不拘于受病之因，不拘于发病之时为施治。如夏月盛暑而伤寒吐利，多有用姜、附、吴萸而始效，隆冬严寒而病温，多有用石膏、硝、黄而热乃解者。今谓麻桂二汤只宜于冬月之正伤寒，而三时不可轻用，其失岂不多乎？夫开口言伤寒，动手反用寒凉克伐之剂，曷不于伤寒二字顾名思义耶？寒伤于表，法当温散；寒伤于里，法当温补。仲景治伤寒，只有温散、温补二法。其清火、凉解、吐下等法，正为温暑时疫而设，所以治热，非以治寒，治热淫于内，非治寒伤于表也。今伤寒家皆曰仲景治温治暑，必另有法治，今遗失而无。惟伤寒只有汗吐下三法，将温补正法，置之不用，反曰治伤寒无补法。于是人伤于天地之寒者轻，伤于医师之法者重；死于饮食之内伤者少，死于寒药之内伤者多耳。
Wind and cold, the two qi, have a distinction of yin and yang, and they cause disease mutually. If wind is without cold, it is gentle wind; once it carries cold pathogen, invading the person and causing illness, its symptoms are similar to Shanghan (Cold Damage), so it can also be named Shanghan. Therefore, wind and cold exist in all four seasons, but are most severe in winter. Shanghan and Fengzhong (Wind Strike) each have degrees of severity, which lies not in their names but in their presenting symptoms. In the Taiyang Chapter of *Shanghan Lun*, there are two descriptions of Fengzhong pulse and symptoms: one states that Taiyang Fengzhong presents with floating-yin and weak-yin pulses; floating-yang indicates spontaneous heat, while weak-yin indicates spontaneous sweating, accompanied by aversion to cold, aversion to wind, mild fever, nasal congestion, and dry retching, treated with Guizhi Tang (Cinnamon Twig Decoction). The other states that Taiyang Fengzhong presents with floating-tight pulses, fever, aversion to cold, body pain, anhidrosis, and irritability, treated with Da Qinglong Tang (Major Blue Green Dragon Decoction). Comparing these two conditions: floating-yang indicates lighter cold, while floating-tight indicates heavier cold; sweating indicates lighter cold, while anhidrosis indicates heavier cold; "se-se xi-xi" (shivering from cold and wind) indicates lighter wind-cold, while "xi-xi" (mild fever) indicates lighter fever; simultaneous fever and aversion to cold indicate heavy cold-heat; nasal congestion indicates lighter wind, while body pain indicates heavier wind; spontaneous sweating and dry retching indicate lighter irritability, while anhidrosis and irritability indicate heavier irritability. There are also two descriptions of Shanghan pulse and symptoms: one states that Taiyang disease, whether fever has not yet appeared or has already appeared, must present with aversion to cold, body pain, vomiting, and nausea, with yin and yang pulses both tight, named Shanghan. The other states that Shanghan presents with floating pulse, spontaneous sweating, frequent urination, mental restlessness, slight aversion to cold, and cramping of the foot. Comparing these two: slight aversion to cold indicates the severity of "must be aversive to cold"; body pain indicates the lightness of foot cramping; spontaneous sweating, frequent urination, and mental restlessness indicate lighter Shanghan; absence of fever indicates lighter fever; initial vomiting and regurgitation indicate heavier Shanghan; floating pulse indicates lighter cold, while tight yin and yang pulses indicate heavier cold. Thus, Fengzhong and Shanghan have such distinctions in severity. Nowadays, people insist that Shanghan is severe and Fengzhong is light, knowing only to distinguish between "Zhong" (Strike) and "Shang" (Damage) of wind and cold, but failing to differentiate the severity of wind and cold. This leads to excuses like "Shanghan showing wind symptoms, Fengzhong showing cold symptoms." Wind is a yang pathogen, cold is a yin pathogen; although both result from seasonal qi influence, each retains its yin-yang nature. Therefore, mild Shanghan resembles Fengzhong completely, except for foot cramping, because the upper body is yang, and wind damages the upper part. Severe Fengzhong resembles Shanghan completely, except for irritability, because cold causes vomiting without irritability, and regurgitation without agitation. However, yin and yang are interdependent roots; irritability (fan) is a yang pathogen, extreme irritability leads to agitation (zao); agitation is a yin pathogen, extreme agitation leads to irritability. Thus, mild Fengzhong has mild irritability, severe Fengzhong has irritability and agitation, severe Shanghan has agitation and irritability, and mild Shanghan has slight irritability. Slight irritability implies slight aversion to cold, meaning weak yang is sufficient to overcome weak cold, hence the pulse is floating but not tight. As stated in this book: "For self-resolution, one must first experience irritability, then sweat resolves it." Because the pulse is floating and not tight, we know resolution comes through sweating. If one attacks the exterior recklessly before self-resolution, yang collapse occurs due to weak yang. Whenever Shanghan presents with irritability, cold qi is about to resolve. Agitation and irritability mean yang is constrained by cold, and the pathogen becomes stronger. Thus, on the first day of Shanghan, if there is agitation and irritability, the disease is about to transmit; on the sixth or seventh day, agitation and irritability mean yang is leaving to enter yin. Because patients' innate yang qi differs, and the sites of pathogen invasion and yin-yang conditions vary, yang has abundance or scarcity, and heat has mildness or severity. For example, Taiyang is the primordial Great Yang; its heat arises from Ying and Wei, causing robust heat in the whole body and limbs. Yangming is the combination of Shaoyang and Taiyang yang; its heat arises in the muscles, causing steaming heat. Shaoyang is the half-exterior half-interior yang; its heat arises in the interstices, opening and closing intermittently, causing alternating chills and fever. These are the differences in fever among the three yang meridians. Taiyin is Extreme Yin, having no heat to emit; because the stomach circulates fluids to nourish the four peripheries, it governs the four limbs, so heat manifests in the hands and feet. Therefore, in Taiyin Shanghan, hands and feet are naturally warm; in Taiyin Fengzhong, the four limbs are painful and irritable. Shaoyin is the root of storage; if Shaoyin fails to store, Kan Yang has no cover. Thus, some initially suffer wind-cold with deep pulse and fever, or initially have no exterior heat, but after eight or nine days, heat enters the Bladder, causing heat throughout the body and limbs. Jueyin represents the end of two yins and the beginning of one yang. In its Shanghan, some start with yin, experiencing cold extremities first then fever; others start with yang, experiencing fever first then cold extremities; or yang advances with more heat and fewer cold extremities, or yang retreats with less heat and more cold extremities, or yin and yang harmonize with corresponding cold extremities and fever. These are the differences in fever among the three yin meridians. Taiyang is Father, often suffering from excessive yang diseases. For instance, after taking Guizhi Tang, one might feel worse with irritability, or feel worse again after half a day, or after purgation, the pulse remains floating with Qi rushing upward, or without sweating but with agitation, or after medication symptoms slightly subside but irritability and drowsiness lead to epistaxis; all these are due to heavy yang. Shaoyin is Female, often suffering from yang collapse. For example, diarrhea with undigested food, cold extremities, pulse faint and nearly absent, aversion to cold with curled posture, vomiting and diarrhea with sweating, interior cold with exterior heat, non-irritability but agitation—all are due to yang collapse. Also, *Neijing·Bingxing Pian* says: "Pathogen striking the nape descends to Taiyang; striking the face descends to Yangming; striking the cheek descends to Shaoyang; striking the chest, back, and flanks also strikes their meridians." Thus, in this book, Taiyang pathogen invasion has differences between striking the nape and the back; striking the nape causes stiff neck and head, striking the back causes stiff back. Yangming has differences between striking the face and the chest; striking the face causes eye pain and dry nose, striking the chest causes fullness and hardness in the chest. Shaoyang has differences between striking the cheek and the flank; striking the cheek causes bitter taste and dry throat, striking the flank causes fullness and hardness under the ribs. This is Qibo's principle of yang pathogen entering meridians. It also says: "Pathogen striking yin starts from the arm, moving from meridian to zang; if zang qi is solid and cannot contain it, the pathogen returns to the fu." Thus, all three yin meridians in this book have spontaneous diarrhea, indicating cold pathogen returning to fu; all three yin meridians have indications for purgation, indicating heat pathogen returning to fu. This is Qibo's principle of yin pathogen entering fu. The positions of the six meridians have high and low, so the days of pathogen invasion have near and far. Taiyang is the first of the three yang, highest in the exterior, most susceptible to Shanghan, so it is affected on the first day. Yangming is the second of the two yang, located anteriorly, so affected on the second day. Shaoyang is the first of the one yang, located laterally, so affected on the third day. Taiyin is the third of the three yin, highest in the yin position, so affected on the fourth day. Shaoyin is the second of the two yin, located centrally in yin, so affected on the fifth day. Jueyin is the first of the one yin, at the end of the three yin, so affected on the sixth day. These refer to the timing of symptom appearance, not the sequential transmission of the six meridians. *Neijing* says: "Qi has high and low, disease has near and far, reaching its destination." This is the meaning. Regarding the term "transmission" in this book, meanings vary; forcing a theory of meridian transmission is erroneous. Shanghan on the first day affects Taiyang; if the pulse is quiet, it is not transmitting, meaning heat transmits within the same meridian, not to Yangming. Yangming has nowhere further to transmit; initial aversion to cold stops spontaneously on the second day, meaning cold transmits within the same meridian, not to Shaoyang. On the second and third days of Shanghan, if Yangming and Shaoyang symptoms do not appear, it is not transmitting, referring to heat transmitting within the same meridian, not transmitting to Yangming on day two and Shaoyang on day three. Taiyang disease healing after seven days is because the meridian cycle is complete. It means on the day of return (day seven), the Taiyang meridian disease should end, not that one meridian is transmitted daily, re-transmitting to Taiyang on day seven. If it were re-transmission, it would not say "complete"; if daily transmission, it would not say "traversing the meridian." If it were to restart as a meridian disease, Taiyang would not cease but combine with Yangming. Transmission or non-transmission means preventing Yangming from receiving heat from Taiyang, not re-transmitting to Shaoyang. Since Taiyang, Yangming, and Shaoyang are geographically close, if Taiyang yang excess does not cease, it transfers to Yangming; if yang decline does not cease, it attaches to Shaoyang. If yang sinks, it attaches to Taiyin; if yang deficiency, it enters Shaoyin; if yang rebels, it transfers to Jueyin. Yangming is the gathering place of all things, so all six meridians can transfer to it. But since Yangming has nowhere further to transmit, we know Taiyang and Yangming do not have symptoms transferring to Shaoyang. Yangming and Taiyin both belong to the Stomach; if Stomach is excess, Taiyin transfers to Yangming; if Stomach is deficient, Yangming transfers to Taiyin. Shaoyin is geographically close to the other two yin meridians; receiving Taiyin cold causes vomiting, diarrhea, and undigested food; receiving Jueyin heat causes sore throat and bloody stool. Jueyin is the end of yin, just as Yangming has nowhere further to transmit; however, when yin emerges to yang, there is more heat and fewer cold extremities; when yin extreme leads to yang collapse, there is less heat and more cold extremities. This is the variable pattern of Shaoyang's alternating chills and fever. According to this book: "Taiyang disease, with fever, sweating, aversion to wind, and slow pulse, is Fengzhong." Also: "Taiyang Fengzhong, with floating-tight pulse, anhidrosis, and irritability." Also: "Yangming Fengzhong, with string-like, floating, large pulse, and inability to sweat." Synthesizing these, one cannot say anhidrosis excludes Fengzhong. This book says: "Taiyang disease, whether fever has not yet appeared or has already appeared, must present with aversion to cold, body pain, vomiting, and regurgitation, with yin and yang pulses both tight, named Shanghan," but never mentions anhidrosis. Also: "Taiyang disease with headache, fever, body pain, lower back pain, joint pain, aversion to wind, anhidrosis, and wheezing is treated with Mahuang Tang (Ephedra Decoction)." This does not prefix "Shanghan" nor mention aversion to cold. Also: "Shanghan with floating pulse, spontaneous sweating, and slight aversion to cold." Synthesizing these, one cannot say sweating excludes Shanghan. People only rely on Guizhi Tang treating Fengzhong with spontaneous sweating, ignoring that Shanghan also has spontaneous sweating. They force Mahuang syndrome's anhidrosis to define Shanghan, ignoring that Fengzhong often has anhidrosis. They claim Shanghan has floating-tight pulse and Fengzhong has floating-slow pulse, ignoring that Shanghan can have floating-slow and Fengzhong can have floating-tight. They know three yang meridians have floating pulses and three yin meridians have sinking pulses, ignoring that three yin meridians can have floating pulses and three yang meridians can have sinking pulses. This is relying on isolated statements without considering the whole book. One should know that Mahuang Tang and Da Qinglong Tang are heavy formulas for treating severe Fengzhong, while Guizhi Tang and Gegen Tang are light formulas for mild Fengzhong; Shanghan can use them generally, they are not exclusive to Shanghan. The world promotes Guizhi Tang as the main formula for Fengzhong but dares not promote Da Qinglong Tang for Fengzhong, confused by the fallacy of "Fengzhong showing cold pulse, Shanghan showing wind pulse." Daring not to use Mahuang Tang for Fengzhong stems from the fallacy of "sweating is Fengzhong, anhidrosis is Shanghan." Wind is a yang pathogen, changing with four seasons, and even within a day possessing four-season qi, with different qi movements of depression, recovery, and excess. Thus, there are methods using Mahuang, Guizhi, Gegen, Qinglong, etc. One should know that all four seasons have Fengzhong and Shanghan; one must not stick to the saying "spring injury by wind, winter injury by cold." Taiyang meridian has many Fengzhong formulas, such as Mahuang, Guizhi, Gegen, Da Qinglong. Shaoyin meridian has many Shanghan formulas, such as Mahuang Fuzi Xixin Tang, Zhenwu Tang, Fuzi, Zhuyu, Baitong, Sini Tang, Tongmai Tang, etc. Fengzhong formulas can be adapted for Shanghan, but Shanghan formulas cannot be adapted for Fengzhong, because cold can be warmed, but wind cannot be treated with heat. Wind is a yang pathogen, so Fengzhong, even in Shaoyin, often presents with yang symptoms; cold is a yin pathogen, so Shanghan, even in Taiyang, often presents with yin symptoms. Taiyang meridian has many Fengzhong symptoms, yang follows yang; Shaoyin meridian has many Shanghan symptoms, yin follows yin. Wind moves swiftly and changes frequently, so pulse and symptoms cannot be rigidly fixed. Observing changes: symptoms may include spontaneous sweating and nasal congestion, or anhidrosis and wheezing, or anhidrosis and irritability, or diarrhea and vomiting, or thirst for water, or alternating chills and fever, or bitter taste and dry throat, or shortness of breath, abdominal fullness, dry nose, and lethargy, or red eyes, deafness, chest fullness, and irritability, or painful and irritable limbs—various and distinct. Pulses may be floating-slow, floating-tight, string-like-floating-large, weak-yin-choppy, or weak-yin-floating—also various and distinct. Observing constants: only floating is the main pulse of Fengzhong, and aversion to wind is the fixed symptom of Fengzhong. Wind pulse varies abnormally, but floating is its true form; wind symptoms change endlessly, but aversion to wind is its true emotion. Zhang Zhongjing widely established various formulas to exhaustively cover these variations. Cold injuring humans has three sources: morning and evening fog/dew, wind/rain in four seasons, frost/snow in winter/spring—this is heaven's cold qi; secluded rooms, brick floors/stone steps, great rivers/deep marshes, deep valleys/high mountains—this is earth's cold qi; liking cold spring water, preferring raw/cold food, craving fruits/melons, mistakenly taking cold medicine—this is human cold qi. This principle is shallow, yet few Shanghan books mention it, covering it instead with winter cold, spring warmth, and epidemic diseases. Why not seek the cause of disease and attribute it to seasonal changes? Although cold is winter qi, do the other three seasons necessarily lack cold? Cold has severity, injury has severity, not fixed to winter. Warmth is spring qi, but warmth sickness occurs in other seasons too, and warmth arising with time is common, while resulting from winter Shanghan is rare; it cannot be said to be an inevitable law. Even if warmth sickness occurs in winter, it arises due to the person's yin deficiency; how could winter's warm qi be toxic to harm humans? If epidemic qi is the toxicity of heaven and earth's warmth, when cool wind blows, epidemic evil disperses naturally; how could it worsen upon encountering cold? Epidemic and cold are unrelated like wind and cattle/horses; why label epidemic qi with cold? If illness results from sudden cold restraint, it is simply Shanghan in the three seasons, do not wrongly name it epidemic. Claiming that in months 3-4 yang qi is weak, so cold restraint causes mild heat; in months 5-6 yang qi is strong, so cold restraint causes severe heat; in months 7-8 yang qi declines, so cold restraint causes slight heat—is Shuhe's baseless theory. When treating cold or heat diseases, one must examine the patient's yin-yang abundance and decline, not be bound by weather cold or heat. Weather cold/heat harming humans depends on the patient's yin-yang quantity and yuan qi deficiency/excess for severity, not solely determined by seasonal yin-yang. Therefore, Zhongjing's formula creation prioritizes balancing pulse and distinguishing symptoms, not bound by cause of disease or time of onset. For example, in summer heat, Shanghan with vomiting/diarrhea often responds to Ginger, Aconite, and Evodia; in deep winter cold, warmth sickness often resolves with Gypsum, Nitre, and Rhubarb. Now claiming Mahuang and Guizhi decoctions are only suitable for winter proper Shanghan, and should not be lightly used in other seasons—how great is this error! Speaking of Shanghan but acting with cold-cooling attacking agents, why not understand the name Shanghan literally? Cold damaging the exterior requires warming dispersion; cold damaging the interior requires warming tonification. Zhongjing's treatment of Shanghan uses only warming dispersion and warming tonification. His methods of clearing fire, cooling resolution, emesis, and purgation are designed for warmth, summer heat, and epidemics, thus treating heat, not cold; treating heat overflowing internally, not cold damaging the exterior. Today's Shanghan practitioners say Zhongjing's treatment of warmth and summer heat must have other lost methods. They claim Shanghan has only emesis, sweating, and purgation methods, discarding the correct warming tonification method, and falsely claiming Shanghan treatment has no tonification. Thus, people injured by heaven-earth cold are lightly harmed, but heavily harmed by physicians' methods; few die from internal dietary injury, but many die from internal cold medicine injury.