读仲景之书。当求其所以立法之意。苟得其所以立法之意。则知其书足以为万世法。而后人
莫能加。莫能外矣。苟不得其所以立法之意。则疑信相杂。未免通此而碍彼也。呜呼。自仲
景以来。发明其书者。不可以数计。然其所以立法之意。竟未闻有表章而示人者。岂求之而
不得之欤。将相循习而不求欤。抑有之而余未之见欤。余虽不敏。 请陈之。夫伤于寒。有即
病者焉。有不即病者焉。即病者。发于所感之时。不即病者。过时而发于春夏也。即病谓之
伤寒。不即病谓之温与暑。夫伤寒温暑。其类虽殊。其所受之原。则不殊也。由其原之不殊
。故一以伤寒而为称。由其类之殊。故施治不得以相混。以所称而混其治。宜乎贻祸后人。
以归咎于仲景之法。而委废其太半也。吁。使仲景之法。果贻祸于后人。伤寒论不作可也
。使仲景之法。果不贻祸于后人。伤寒论其可一日缺乎。后人乃不归咎于已见之未至。而归
咎于立法之大贤。可谓溺井怨伯益。失火怨燧人矣。夫仲景法之祖也。后人虽移易于穷。终
莫能越其矩度。由莫能越而观之。则其法其方。果可委废太半哉。虽然。立言垂训之士。犹
不免失于此。彼碌碌者。固无足诮矣。夫惟立言垂训之士。有形乎着述之间。其碌碌者当趑
趄犹预之余。得不靡然从令争先快睹而 简略之地乎。夫其法其方委废太半而不知返。日
惟
简便是 。此民生之所以无籍。而仲景之心之所以不能别白矣。呜呼。法也。方也。仲景
专为即病之伤寒设。不兼为不即病之温暑设也。后人能知仲景之书。本为即病者设。不为不
即病者设。则尚恨其法散落所存不多。而莫能御夫粗工妄治之万变。果可惮烦而或废之乎。
是知委废太半。而不觉其非者。由乎不能得其所以立法之意故也。今人虽以治伤寒法治温暑
。亦不过借用耳。非仲景立法之本意也。犹六书假借。虽移易于穷。终非造字之初意。夫仲
景立法。天下后世之权衡也。故可借焉以为他病用。虽然。岂特可借以治温暑而已。凡杂病
之
治。莫不可借也。今人因伤寒治法。可借以治温暑。遂谓其法通为伤寒温暑设。吁。此非识
流而昧原者欤。苟不余信。请以证之。夫仲景之书。三阴经寒证。居热证什之七八。彼不即
病之温暑。但一于热耳。何由而为寒哉。就三阴寒证而详味之。然后知余言之不妄。或者乃
谓三阴寒证。本是杂病。为王叔和增入其中。又或谓其证之寒。盖由寒药误治而致。若此者
皆非也。夫叔和之增入者。辨脉平脉与可汗可下等诸篇而已。其六经病篇。必非叔和所能
辞也。但厥阴经中下利呕哕诸条。却是叔和因其有厥逆而附。遂并无厥逆而同类者。亦附之
耳。至若以药误治。而成变证。则惟太阴为多。纵使三阴证。亦或有寒药误治而变寒者。然
岂应如是之众乎。夫惟后人以仲景书通为伤寒温暑设。遂致诸温剂皆疑焉。而不敢用。韩只
和虽觉桂枝汤之难用。但谓今昔之世不同。然未悟仲景书。本为即病之伤寒设也。且其着微
旨一书。又纯以温暑作伤寒立论。而即病之伤寒。反不言及。此已是舍本徇末。全不能窥仲
景藩篱。又以夏至前。胸膈满闷。呕逆。气塞。肠鸣。腹痛。身体拘急。手足逆冷等证。视为
温
暑。谓与仲景三阴寒证。脉理同。而证不同。遂别立温中法以治。夫仲景所叙三阴寒证。乃
是冬时即病之伤寒。故有此证。今欲以仲景所叙三阴寒证。求对于春夏温暑之病。不亦 乎
。虽然。祗和未悟仲景立法本旨。而又适当温暑病作之际。其为惑也。固宜。以余观之。其
胸膈满闷。呕逆。气寒等证。若非内伤冷物。则不正暴寒所中。或过服寒药所变。或内外俱
伤于寒之病也。且祗和但曰寒而当温然未尝求其所以为寒之故。能求其故。则知温暑本无寒
证矣。改之仲景书。虽有阴毒之名。然其所叙之证。不过面目青。身痛如被杖。咽喉痛而已
。并不言阴寒极甚之证。况其所治之方。亦不过升麻甘草当归鳖甲而已。并不用大温大热之
药。是知仲景所谓阴毒者。非阴寒之病。乃是感天地恶毒异气。入于阴经。故曰阴毒耳。后
之论者。遂以为阴寒极甚之证。称为阴毒。乃引仲景所叙。面目青。身痛如被杖。咽喉痛数
语。并而言之。却用附子散。正阳散等药以治。窃谓阴寒极甚之证。固亦可名为阴毒。然终
非仲景所以立名之本意。观后人所叙阴毒。与仲景所叙阴毒。自是两般。岂可混论。后人所
叙阴毒。亦只是内伤冷物。或不正暴寒所中。或过服寒药所变。或内外俱伤于寒而成耳。非
天地恶毒异气所中者也。朱奉议作活人书。累数万言。于仲景伤寒论多有发明。其伤寒即入
阴经为寒证者。诸家不识。而奉议识之。但惜其亦不知仲景专为即病者立法。故其书中。每
每以伤寒温暑混杂议论。竟无所别。况又视伤寒论为全书。遂将次传阴经热证。与即入阴经
寒证。牵合为一立说。且谓大抵伤寒。阳明证宜下。少阴证宜温。而于所识即入阴经之见。
又未免自相悖矣。夫阳明证之宜下者。固为邪热入胃。其少阴证。果是伤寒传经热邪。亦可
温乎。况温病暑病之少阴。尢不可温也。自奉议此说行。而天下后世蒙害者。不无矣。迨夫
成无己作伤寒论注。又作明理论。其表章名义纤悉不遗。可谓善羽翼仲景者。然即入阴经之
寒证。又不及朱奉议能识。况即病立法之本旨乎。宜其莫能知也。惟其莫知。故于三阴诸寒
证。止随文解义而已。未尝明其何由不为热。而为寒也。至于刘守真出。亦以温暑作伤寒立
论。而遗即病之伤寒。其所处辛凉解散之剂。固为昧者有中风伤寒错治之失而立。盖亦不无
桂枝麻黄难用之惑也。既惑于此。则无由悟夫仲景立桂枝麻黄汤之有所主。用桂枝麻
黄汤之有其时矣。故其原病式有曰。夏热用麻黄桂枝之类热药发表。须加寒药。不然。则热
甚发黄。或斑出矣。(此说出于庞安常。而朱奉议亦从而和之。)殊不知仲景立麻黄汤桂枝汤
。本不欲用于夏热之时也。苟悟夫桂枝麻黄汤本非治温暑之剂。则群疑冰泮矣。何也。夫寒
之初客于表也。闭腠理郁阳气而为热。故非辛温之药。不能开腠理以泄其热。此麻黄汤之所
由立也。至于风邪伤表。虽反疏腠理而不能闭。然邪既客表。则表之正气受伤。而不能流
通。故亦发热也。必以辛甘温之药发其邪。则邪去而腠理自密矣。此桂枝汤之所由立也。其
所以不加寒药者。盖由风寒在表。又当天令寒冷之时。而无所避故也。后人不知仲景立法之
意。故有惑于麻黄桂枝之热。有犯于春夏之司气。而不敢用。于是有须加寒药之论。夫欲加
寒药于麻黄桂枝汤之中。此乃不悟其所以然。故如此耳。若仲景为温暑立方。必不如此。必
别有法。但惜其遗佚不传。致使后人有多岐之患。若知仲景伤寒论。专为即病伤寒作。则知
麻黄桂枝所以宜用之故。除传经热证之外。其直伤阴经。与太阳不郁热。即传阴经诸寒证。
皆有所归着。而不复疑为寒药误下而生矣。若乃春夏有恶风恶寒纯类伤寒之证。盖春夏暴中
风寒之新病。非冬时受伤过时而发者。不然。则或者温暑将发。而复感于风寒。或因感风寒
。而动乎久郁之热。遂发为温暑也。仲景曰。太阳病。发热而渴。不恶寒者。为温病。观此
。则知温病不当恶寒。而当渴。其恶寒而不渴者。非温病矣。仲景虽不言暑病。然暑病与温
病同。但复过一时。而加重于温病耳。其不恶寒而渴。则无异也。春夏虽有恶风恶寒表证。
其桂枝麻黄二汤。终难轻用。勿泥于发表不远热之语也。于是用辛凉解散。庶为得宜。苟不
慎而轻用之。诚不能免夫狂躁。斑黄。衄血之变。而亦无功也。虽或者行桂枝麻黄于春夏而
效。乃是因其辛甘发散之力。偶中于万一。断不可视为常道而守之。今人以败毒散。参苏饮
。通解散。百解散之类。不问四时中风伤寒。一例施之。虽非至正之道。较之不慎。而轻用
麻黄桂枝于春夏。以致变者。则反庶几。然败毒散等若用于春夏。亦止可治暴中风寒之证
而
已。其冬时受伤过时而发之温病暑病则不宜用也。用则非徒无益亦反害之矣。纵或有效。亦
是
偶然。彼冬时伤寒。用辛凉发表。而或效者。亦偶然也。凡用药治病。其既效之后。须要明
其当然与偶然。能明其当然与偶然。则精微之地。安有不至者乎。惟其视偶然为当然。所以
循非踵弊。莫之能悟。而病者不幸矣。若夫仲景于三阴经。每用温药。正由病之所必须。与
用之有其时耳。余有别论。兹不再具。若概以三阴寒证。视为杂病而外之。得无负于仲景济
人利物之至仁。而误后世乎。自近代先觉。不示伤寒温暑异治之端绪。但一以寒凉为主。而
诸
温热之剂。悉在所略。致使后之学人。视仲景书。欲仗焉。而不敢以终决。欲弃焉。则犹以
为立法之祖。而莫能外。甚则待为文具。又甚则束之高阁。而谓其法宜于昔。而不宜于今。
由治乱动静之殊治。静属水。乱动属火。故其温热之药。不可用于今属火之时也。噫。斯
言也。其果然耶否耶。但能明乎仲景本为即病者设法。则桂枝麻黄自有所用。诸温热之剂。
皆不可略矣。若谓仲景法。不独为即病者设。则凡时行及寒疫温疟风温等病。亦通以伤寒六
经病诸方治之乎。伤寒例曰。冬温之毒。与伤寒大异。为治不同。又曰寒疫与温及暑病相似
。但治有殊耳。是则温暑及时行寒疫温疟风温等。仲景必别有治法。今不见者。亡之也。观
其所谓为治不同。所谓温疟。风温。温毒。温疫。脉之变证方治如说。岂非亡其法乎。决不
可以伤寒六经病诸方通治也。夫素问谓人伤于寒。则为病热者。言常而不言变也。仲景谓或
热或寒而不一者。备常与变而弗遗也。仲景盖言古人之所未言。大有功于古人者。虽欲偏废
可乎。叔和搜采仲景旧论之散落者以成书。功莫大矣。但惜其既以自己之说。混于仲景所
言
之中。又以杂脉杂病纷纭并载于卷首。故使玉石不分。主客相乱。若先备仲景之言。而次附
己说。明书其名。则不致惑于后人。而累仲景矣。昔汉儒妆拾残编断简于秦火之余。加以传
注。后之议者。谓其功过相等。叔和其亦未免于后人之议欤。余尝欲编类其书。以伤寒例居
前。而六经病次之。相类病又次之。瘥后病又次之。诊察。治法。治禁。治误。病解。未解
等。又次之。其杂脉杂病与伤寒有所关者。采以附焉。其与伤
寒无相关者。皆删去。如此。庶几法度纯一。而玉石有分。主客不乱矣。然有志未暇。姑叙
此。以俟他日。
阅读张仲景的著作，应当探求他确立治疗法则的初衷。如果能领会他确立法则的初衷，就知道他的书足以成为万世的准则，后人无法超越，也无法脱离它。如果不能领会他确立法则的初衷，就会疑惑与信任混杂，难免顾此失彼。唉！自张仲景以来，阐发他著作的人不计其数，然而关于他确立法则的初衷，竟然没有听说有人加以表彰并展示给世人。是寻求而不得吗？还是沿袭习惯而不加寻求呢？或者是已经有了但我没见到呢？我虽然不聪明，请让我陈述一下我的观点。
受寒邪侵袭，有立即发病的，也有不立即发病的。立即发病的，是在感受邪气的时候发作；不立即发病的，是过了时节在春夏季节发作。立即发病的称为伤寒，不立即发病的称为温病和暑病。伤寒、温病、暑病，它们的类别虽然不同，但它们所受邪气的本源却是一样的。正因为本源相同，所以都统称为“伤寒”；正因为类别不同，所以施治时不能混淆。如果因为名称相同就混淆了治疗方法，这必然会祸害后人，导致人们归咎于张仲景的法度，从而废弃其中大半的内容。唉！如果张仲景的法度真的祸害了后人，《伤寒论》不写也罢；如果张仲景的法度真的没有祸害后人，《伤寒论》难道可以一天缺失吗？后人却不归咎于自己见识不到家，反而归咎于制定法度的大贤人，这就像掉进井里怨恨发明掘井技术的伯益，发生火灾怨恨发明钻木取火的燧人氏一样。
张仲景的法度是后世之祖，后人即使面临穷困变易，终究不能超越他的规矩法度。从无法超越这一点来看，他的法度和方剂，真的可以废弃大半吗？话虽如此，那些著书立说、垂范后世的学者，尚且不免在此处犯错，那些平庸之辈就更不值得指责了。只有那些著书立说的人，在著作中留下了痕迹，而那些平庸之辈在犹豫不决之后，能不盲目顺从命令，争先恐后地看到简略之处吗？他们的法度和方剂被废弃大半而不知回头，整天只追求简便，这就是百姓无所依靠，而张仲景的本心无法辩白清楚的原因啊。
唉！法度和方剂，张仲景是专门为了“即病”的伤寒设立的，并不是兼为“不即病”的温病和暑病设立的。后人如果能知道张仲景的书本是专为即病者设立，不为不即病者设立，那么还会遗憾他的法度散落留存不多，而不能抵御庸医妄治的千变万化。如果真的担心麻烦而废弃它，那怎么行呢？由此可知，废弃大半而不觉其错误的原因，是由于不能领会他确立法则的初衷。现在的人虽然用治疗伤寒的方法来治疗温病和暑病，也不过是借用罢了，并非张仲景立法本意。这就好比六书中的假借字，虽然遇到穷困变易时可以借用，但终究不是造字时的本意。
张仲景确立的法度，是天下后世的权衡标准，所以可以借用来治疗其他疾病。话虽如此，难道仅仅可以借用来治疗温病和暑病吗？凡是杂病的治疗，没有不可以借用的。现在的人因为伤寒治法可以借用来治疗温病和暑病，就认为这些法度是通用于伤寒、温病和暑病的设立的。唉！这不是只知支流而昧于本源的人吗？如果不相信我，请让我证明这一点。
张仲景的书中，三阴经的寒证占热证的十分之七八。那些不立即发病的温病和暑病，只是一味地表现为热证，怎么会变成寒证呢？仔细体味三阴经的寒证，然后就知道我的话不是妄言。或许有人会说，三阴经的寒证本来就是杂病，是王叔和增补进去的；又有人说，那些寒证是因为误用寒药治疗导致的。像这样的说法都不对。王叔和增补的，只是《辨脉》、《平脉》以及《可汗》、《可下》等篇章而已。至于六经病篇，一定不是王叔和所能篡改的。只是《厥阴经》中关于下利、呕吐、哕逆等条文，确实是王叔和因为他有厥逆症状而附带的，于是连没有厥逆症状但属于同类情况的也一并附上了。至于因药物误治而成变证的，只有太阴经比较多。即使三阴经的证候，也许有因误用寒药而变为寒证的，但难道会多到这种程度吗？
正是因为后人认为张仲景的书是通用于伤寒、温病和暑病设立的，导致所有的温热药剂都被怀疑而不敢使用。韩祗和虽然觉得桂枝汤难以使用，但只说是今昔时代不同，然而并没有领悟张仲景的书本是专为即病的伤寒设立的。而且他所著的《微旨》一书，又纯粹以温病和暑病当作伤寒来立论，而对于即病的伤寒反而不提。这已经是舍本逐末，完全不能窥探张仲景的门径。他又将夏至前出现的胸膈满闷、呕吐逆气、气塞、肠鸣、腹痛、身体拘急、手足逆冷等证候，视为温病和暑病，认为这与张仲景所说的三阴寒证脉理相同而症状不同，于是另外创立温中法来治疗。张仲景所叙述的三阴寒证，乃是冬季即病的伤寒，所以才有这些证候。现在想要用张仲景所叙述的三阴寒证，去对应春夏季节的温病和暑病，不也是错误的吗？
虽然韩祗和没有领悟张仲景立法的本旨，而又恰逢温病和暑病发作的时候，他的困惑固然是应该的。在我看来，他所说的胸膈满闷、呕吐逆气、气寒等证候，如果不是内伤生冷食物，就是被不正之气或暴寒所中，或者是过服寒药导致的变证，或者是内外都受寒邪侵袭的病。而且韩祗和只说这是寒证应当用温药，却从未探究其之所以为寒的原因。如果能探究其原因，就知道温病和暑病本来就没有寒证。
修改张仲景的书，虽然有“阴毒”这个名称，但他所叙述的证候，不过是面目青黑、身体疼痛如被杖打、咽喉痛而已，并不提及阴寒极盛的证候。况且他所治疗的方剂，也不过是升麻、甘草、当归、鳖甲而已，并不使用大温大热的药物。由此可知，张仲景所说的“阴毒”，并不是阴寒的病，而是感受天地间的恶毒异气，侵入阴经，所以叫作“阴毒”。后来的论述者，便以为这是阴寒极盛的证候，称之为阴毒，于是引用张仲景所叙述的面目青、身痛如被杖、咽喉痛这几句话，合并在一起，却使用附子散、正阳散等药物来治疗。我认为，阴寒极盛的证候，固然也可以命名为阴毒，但这终究不是张仲景立名的本意。看后人所叙述的阴毒，与张仲景所叙述的阴毒，自然是两回事，怎么能混为一谈呢？后人所叙述的阴毒，也只是内伤生冷食物，或被不正暴寒所中，或因过服寒药变证，或内外俱伤于寒而形成的，并不是被天地恶毒异气所中的。
朱奉议撰写《活人书》，累计数万言，对张仲景《伤寒论》多有阐发。对于伤寒直接传入阴经成为寒证的情况，各家都不认识，而朱奉议认识到了。可惜他也不知道张仲景是专门为即病者确立法则的，所以他的书中，常常将伤寒和温病、暑病混杂议论，竟然没有分别。况且他又把《伤寒论》当作全书，于是将次传至阴经的热证，与直接传入阴经的寒证，牵强地合为一说立论。并且说大抵伤寒，阳明证宜用下法，少阴证宜用温法。而对于他所认识的直接传入阴经的见症，又未免自相矛盾了。阳明证宜用下法，固然是因为邪热入胃；那个少阴证，果真是伤寒传经的热邪，也可以用温法吗？况且温病、暑病的少阴证，尤其不可用温法。自从朱奉议这种说法流行，天下后世蒙受危害的人，不在少数。
等到成无己撰写《伤寒论注》，又撰写《明理论》，他对名义的表彰详尽无遗，可以说是善于辅翼张仲景的人了。然而对于直接传入阴经的寒证，又不如朱奉议能认识清楚，更何况是即病立法的本旨呢？所以他自然不能知晓。正因为不知道，所以对于三阴经的各种寒证，只是随文解释义理而已，未曾明确说明它们为什么不是热证而是寒证。
到了刘守真出现，也以温病和暑病当作伤寒来立论，而遗漏了即病的伤寒。他所处方的辛凉解散剂，固然是为了迷惑之人将中风和伤寒错治而设立的，大概也不免有桂枝汤、麻黄汤难以使用的困惑。既然对此困惑，就无法领悟张仲景设立桂枝汤、麻黄汤是有特定主治和使用时机的。所以他在《原病式》中说：“夏天炎热时使用麻黄、桂枝这类热药发表，必须加入寒药，否则，就会热甚发黄，或者出现斑疹。”（这种说法出自庞安常，朱奉议也附和它。）殊不知张仲景设立麻黄汤、桂枝汤，本就不打算在夏天炎热的时候使用。如果能领悟桂枝汤、麻黄汤本就不是治疗温病和暑病的药剂，那么各种疑惑就会像冰融化一样消散。为什么呢？寒邪初客于体表，闭塞腠理，郁积阳气而发热，所以非辛温的药物，不能开泄腠理以发散其热。这就是麻黄汤设立的原因。至于风邪伤表，虽然使腠理疏松而不能闭塞，但邪气既然客居体表，体表的正气受伤，不能流通，所以也会发热。必须用辛甘温的药物发散邪气，邪气去除而腠理自然致密。这就是桂枝汤设立的原因。它们之所以不加寒药，是因为风寒在体表，又正值天气寒冷之时，无处躲避的缘故。
后人不知道张仲景确立法则的初衷，所以对麻黄、桂枝的热性感到困惑，触犯春夏季节的主气而不敢使用，于是有了必须加入寒药的说法。想要在麻黄汤、桂枝汤中加入寒药，这是因为不悟其中的道理，所以才这样做。如果张仲景是为温病和暑病设立方剂，一定不会这样，必定另有方法。可惜这些方法遗失未传，致使后人有多歧路的忧患。如果知道张仲景的《伤寒论》是专为即病伤寒所作，就知道麻黄、桂枝适宜使用的缘故。除了传经热证之外，那些直伤阴经，以及太阳经不郁热、直接传入阴经的各种寒证，都有了归宿，不再怀疑是寒药误下而产生的变证。
至于春夏季节有恶风、恶寒纯类伤寒的证候，那是春夏季节突然中风的新的病证，不是冬季受伤过后时才发作的。不然，就是温病和暑病将要发作，又复感风寒；或者因为感受风寒，而动摇了久郁的热邪，于是发为温病和暑病。张仲景说：“太阳病，发热而渴，不恶寒者，为温病。”看这句话，就知道温病不应当恶寒，而应当口渴。那些恶寒而不口渴的，就不是温病。张仲景虽然没有提及暑病，但暑病与温病相同，只是经过一段时间加重于温病罢了。其不恶寒而口渴，则没有不同。春夏季节虽然有恶风、恶寒的表证，但桂枝汤、麻黄汤终究难以轻易使用，不要拘泥于“发表不远热”的话。于是使用辛凉解散的方法，才比较得当。如果不谨慎而轻率使用，确实不能避免狂躁、发斑、发黄、鼻衄等变证，而且也没有功效。虽然有的人在春夏季节使用桂枝汤、麻黄汤而有效，那是凭借它们辛甘发散的力量，偶然中了对症，绝对不可以视为常道而坚守。现在的人用败毒散、参苏饮、通解散、百解散之类，不问四季中风伤寒，一律施用。虽然这不是最正确的道路，但比起不谨慎而轻率在春夏使用麻黄、桂枝以致产生变证的人来说，反而稍微接近正确。然而败毒散等药如果在春夏使用，也只可治疗暴感风寒的证候而已，对于冬季受伤过后才发作的温病和暑病则不宜使用。如果使用，不仅无益，反而有害。纵然偶尔有效，也是偶然。那些冬季伤寒，使用辛凉发表而有效的，也是偶然的。凡是用药治病，在既然后有效，必须明白什么是必然的，什么是偶然的。能明白必然与偶然，那么在精微的地方，哪有不到的呢？正因为把偶然当作必然，所以沿着错误跟随弊端，没有人能醒悟，病人也就很不幸了。
至于张仲景在三阴经每用温药，正是由于病情所必需，以及使用时机恰当罢了。我有别的论述，这里不再详述。如果把三阴经的寒证一概视为杂病而排斥在外，岂不是辜负了张仲景济世救人的至仁之心，而误导后世吗？自近代以来的先觉之士，不指示伤寒和温病、暑病不同治疗的端绪，只是一味以寒凉为主，而所有温热药剂都被忽略。致使后学之人，看待张仲景的书，想依靠它，却不敢最终决断；想抛弃它，又还认为是立法的祖先，无法脱离。甚至把它当作装饰性的文字，更甚者束之高阁，认为它的法度适宜于古代，而不适宜于现代。理由是治乱动静不同，静属水，乱动属火，所以温热药不可用于现在属火的时代。唉！这话果真对吗？还是不对呢？只要能明白张仲景本是为即病者设立方法，那么桂枝汤、麻黄汤自然有其用处，各种温热药剂都不可忽略了。如果说张仲景的法度不只是为即病者设立，那么凡时行感冒及寒疫、温疟、风温等疾病，也都通用地用伤寒六经病的诸方治疗吗？《伤寒例》说：“冬温的毒气，与伤寒大不相同，治疗方法也不同。”又说：“寒疫与温病及暑病相似，但治疗方法有差异。”这说明温病、暑病及时行感冒、寒疫、温疟、风温等，张仲景必定另有治疗方法，现在不见到的，是失传了。看他所说的“治疗方法不同”，所说的温疟、风温、温毒、温疫，脉象变化、证候及方治如所说，难道不是失传了方法吗？绝对不能拿伤寒六经病的诸方通治。
《素问》说人伤于寒，就会得热病，是说常态而不说变局。张仲景说有的热有的寒而不一致，是备全常态与变局而不遗漏。张仲景大概是说了古人所未说的话，对古人有大功劳，怎么能偏废呢？王叔和搜采张仲景旧论中散落的部分来成书，功劳没有比这更大的了。可惜他既把自己的说法混入张仲景所言之中，又把杂脉、杂病纷纭并载于卷首，致使玉石不分，主客相乱。如果先准备好张仲景的话，其次附上自己的说法，明确书写其名，就不会被后人迷惑，从而连累张仲景了。昔日汉代儒生在秦火之余拾取残编断简，加以传注，后来的议论者说他们功过相等。王叔和恐怕也不免受到后人的议论吧？我曾经想编类他的书，以《伤寒例》居前，六经病次之，相类病又次之，瘥后病又次之，诊察、治法、治禁、治误、病解、未解等，又次之。那些杂脉、杂病中与伤寒有关的，采集附在后面。与伤寒无关的，都删去。这样，法度就能纯正统一，而玉石分明，主客不乱。然而有志向却无暇顾及，暂且叙述这些，以等待日后。
Reading Zhang Zhongjing's works, one should seek the intent behind his establishment of therapeutic principles. If one grasps this intent, one will know that his book serves as a standard for all generations, beyond which later generations cannot go and from which they cannot deviate. If one fails to grasp this intent, doubt and belief will mix, inevitably leading to understanding one aspect while being hindered by another. Alas! Since Zhang Zhongjing, those who have elucidated his work are countless, yet it has never been heard that anyone has explicitly highlighted and demonstrated the intent behind his establishment of principles. Is it because they sought but could not find? Or do they follow habit without seeking? Or perhaps such works exist but I have not seen them? Although I am not intelligent, let me present my view.
Exposure to cold pathogens results in two types: those that manifest immediately (Ji Bing) and those that do not. Immediate manifestation occurs at the time of pathogen acquisition; delayed manifestation occurs after a period of time, during spring and summer. Immediate manifestation is termed "Shanghan" (Cold Damage); delayed manifestation is termed "Wenbing" (Warm Disease) and "Shubing" (Summerheat Disease). Although Shanghan, Wenbing, and Shubing differ in category, their original source of pathogenic acquisition is identical. Because the source is identical, they are collectively referred to as "Shanghan"; because the categories differ, treatments must not be confused. Confusing treatment based on nomenclature would surely harm future generations, causing them to blame Zhang Zhongjing's methods and discard more than half of them. Alas! If Zhang Zhongjing's methods truly harmed future generations, *Shanghan Lun* need not have been written. If they did not harm future generations, how could *Shanghan Lun* be missing even for a day? Yet later generations blame the Great Sage who established the laws rather than their own lack of insight. This is like falling into a well and blaming Boyi (the inventor of digging wells), or suffering fire and blaming Suiren (the inventor of drilling wood for fire).
Zhang Zhongjing's methods are the ancestor for posterity. Even when facing difficulties and changes, later generations ultimately cannot transcend his rules. From this inability to transcend, can his methods and formulas really be discarded by half? Nevertheless, scholars who write books to instruct others still make mistakes here; mediocre individuals are hardly worth criticizing. Only scholars leave traces in their writings. Mediocre individuals, after hesitating, may blindly follow orders, eager to see simplified versions. Their methods and formulas are discarded by half without return, pursuing only simplicity. This is why people lack reliance, and Zhang Zhongjing's true intent remains unclear.
Alas! The laws and formulas were specifically established by Zhang Zhongjing for immediate Shanghan, not jointly for delayed Wenbing and Shubing. If later generations knew that Zhang Zhongjing's book was designed for immediate cases, not delayed ones, they would regret that few methods remain scattered and insufficient to counter the myriad errors of incompetent physicians. Would they dare abandon them due to trouble? Thus, discarding half without realizing the error stems from failing to understand the intent behind establishing the principles. Today, using Shanghan methods to treat Wenbing and Shubing is merely borrowing, not the original intent. It is like the use of borrowed characters in Chinese script; although used when exhausted, it is not the original intent of character creation.
Zhang Zhongjing's principles are the balance for the world and future generations, so they can be borrowed for other diseases. However, is it only for Wenbing and Shubing? Treatments for miscellaneous diseases can also borrow from these principles. People today, seeing that Shanghan methods can treat Wenbing and Shubing, assume these laws apply universally to Shanghan, Wenbing, and Shubing. Are these not those who know the stream but ignore the source? If you do not believe me, let me prove it. In Zhang Zhongjing's book, cold syndromes of the Three Yin meridians account for 70-80% of heat syndromes. Delayed Wenbing and Shubing are purely heat syndromes; how can they become cold? Examining the cold syndromes of the Three Yin meridians closely reveals my words are not false. Some argue that Three Yin cold syndromes are actually miscellaneous diseases added by Wang Shuhe, or that the coldness resulted from misusing cold medicines. These views are incorrect. Wang Shuhe added only chapters like *Bian Mai*, *Ping Mai*, *Ke Han*, and *Ke Xia*. The Six Meridian Disease chapters were certainly not tampered with by him. However, in the Jueyin chapter, items regarding diarrhea, vomiting, and hiccups were indeed attached by Wang Shuhe due to the presence of limb coldness, including similar cases without limb coldness. Regarding changes caused by medication errors, Taiyin is most affected. Even if some Three Yin syndromes became cold due to cold medicine errors, could they be so numerous?
Because later generations believed Zhang Zhongjing's book applied to both Shanghan and Wenbing/Shubing, all warm-tonic medicines were suspected and unused. Han Zhihe felt Guizhi Tang (Cinnamon Twig Decoction) was difficult to use but attributed it to changing times, failing to realize the book was for immediate Shanghan. His book *Weizhi* treats Wenbing and Shubing as Shanghan, ignoring immediate Shanghan. This is abandoning the root for the branch, completely missing Zhang Zhongjing's scope. He viewed symptoms before Summer Solstice—chest fullness, vomiting, qi obstruction, intestinal rumbling, abdominal pain, body stiffness, and cold limbs—as Wenbing/Shubing, claiming they share pulse logic but differ in symptoms from Zhang's Three Yin cold syndromes, thus creating a "Warming Middle" method. Zhang's Three Yin cold syndromes describe winter immediate Shanghan. Applying these to spring/summer Wenbing/Shubing is erroneous.
Although Han Zhihe missed the original intent and was confused during a Wenbing/Shubing outbreak, his symptoms of chest fullness, vomiting, and cold qi likely stem from internal injury from cold food, exposure to violent cold, overuse of cold medicines, or dual internal/external cold injury. Han only stated "cold requires warming" without investigating the cause. Investigating the cause reveals Wenbing/Shubing inherently lack cold syndromes.
Regarding "Yindu" (Yin Toxin) in Zhang's book, the described symptoms are only blueish face, body pain like being beaten, and sore throat, lacking signs of extreme yin-cold. The formulas used (Shengma Gancao Danggui Biejia Tang) contain no strongly warm/hot herbs. Thus, Zhang's "Yindu" refers to toxic qi entering Yin meridians, not an yin-cold disease. Later commentators equated Yindu with extreme yin-cold, citing Zhang's symptoms but treating with Fuzi San (Aconite Powder) or Zhengyang San, which is incorrect. Later descriptions of Yindu involve internal cold injury or external cold, not toxic qi.
Zhu Fenyi's *Huo Ren Shu* elucidates *Shanghan Lun* greatly. He recognized that Shanghan directly entering Yin meridians causes cold syndromes, unlike others. However, he failed to realize Zhang's laws were for immediate cases, mixing Shanghan, Wenbing, and Shubing discussions. He combined secondary transmission heat syndromes with direct entry cold syndromes, stating Yangming requires purgation and Shaoyin requires warming. This contradicts himself: if Shaoyin involves transmitted heat, can it be warmed? Shaoyin in Warm/Sun diseases especially cannot be warmed. Zhu's theory caused harm.
Cheng Wuji's commentary praised terminology meticulously but failed to recognize direct Yin cold syndromes as well as Zhu, let alone the original intent. Consequently, he merely explained texts without clarifying why Three Yin syndromes are cold rather than hot.
Liu Shouzhen also treated Wenbing/Shubing as Shanghan, omitting immediate Shanghan. His acrid-cool dispersing formulas addressed confusion between wind-stroke and Shanghan, reflecting doubts about Guizhi/Mahuang Tangs. Due to this doubt, he missed the specific indications and timing for Zhang's formulas. In *Yuan Bing Shi*, he claimed using Mahuang/Guizhi in summer requires adding cold herbs to prevent jaundice or macules. This view originated from Pang Anchang and was echoed by Zhu. Zhang established Mahuang/Guizhi Tangs not for summer heat. Understanding that these are not for Wenbing/Shubing dispels doubts. Cold initially blocking pores traps yang heat, requiring acrid-warm herbs to open pores (Mahuang Tang). Wind damaging the surface loosens pores but injures righteous qi, causing fever; acrid-sweet-warm herbs disperse evil and close pores (Guizhi Tang). No cold herbs were added because wind/cold is on the surface during cold weather.
Later generations, unaware of the intent, feared the heat of Mahuang/Guizhi in spring/summer, suggesting adding cold herbs. This misunderstanding led to unnecessary modifications. If Zhang prescribed for Wenbing/Shubing, he would have different methods, now lost. Knowing *Shanghan Lun* is for immediate Shanghan clarifies the use of Mahuang/Guizhi. Except for transmitted heat, direct Yin injuries and non-heat-trapped Taiyang transmissions have clear indications, removing suspicion of cold-medicine-induced changes.
Spring/summer aversion to wind/cold resembling Shanghan are new wind-cold attacks, not delayed winter injuries. Alternatively, Wenbing/Shubing onset triggered by wind-cold, or wind-cold stirring long-standing heat. Zhang states: "Taiyang disease, fever with thirst and no aversion to cold is Wenbing." Thus, Wenbing features thirst, not aversion to cold. Aversion without thirst is not Wenbing. Shubing is similar to Wenbing but more severe after time. Spring/summer aversion to wind/cold does not justify light use of Guizhi/Mahuang Tangs; do not cling to "dispersing outward is not far from heat." Acrid-cool dispersal is appropriate. Reckless use causes mania, macules, jaundice, or epistaxis without efficacy. Occasional success in spring/summer is accidental due to acrid-sweet dispersion; do not treat as norm. Modern use of Baidu San, Sushu Yin, etc., for all seasons is flawed but less harmful than reckless Mahuang/Guizhi use. However, these formulas only treat acute wind-cold in spring/summer, not delayed Wenbing/Shubing. Using them then is harmful. Effectiveness is accidental. One must distinguish necessity from accident in treatment. Mistaking accident for necessity leads to persistent errors and patient suffering.
Zhang uses warm medicines for Three Yin because the condition requires it and timing is correct. Discarding Three Yin cold syndromes as miscellaneous diseases betrays Zhang's benevolence. Recent scholars emphasize cold/cool therapies, neglecting warm/hot agents, causing hesitation toward Zhang's book. Some discard it, claiming ancient laws don't fit modern "fire" eras. This is false. Recognizing Zhang's focus on immediate cases validates Guizhi/Mahuang and warm agents. If Zhang's laws covered all seasonal diseases, would *Shanghan Lun* formulas treat epidemic cold, warm malaria, etc.? *Shanghan Li* states Winter Warmth differs from Shanghan. Han Yi resembles Warmth/Summerheat but differs in treatment. Thus, Zhang had distinct methods for these, now lost. *Suwen* states cold injury leads to heat (norm); Zhang covers both norm and variation. Zhang added to ancient knowledge; discarding him is unjustified.
Wang Shuhe compiled Zhang's scattered works, a great merit. But mixing his own theories and miscellaneous pulse/disease chapters at the beginning confused value and obscured authorship. Had he separated Zhang's text from his own notes, confusion would be avoided. Like Han scholars editing Qin remnants, Wang may face criticism. I intended to reorganize the book: *Shanghan Li* first, then Six Meridians, Similar Diseases, Post-illness Care, Diagnosis, Methods, Contraindications, Errors, Resolution, Unresolved, followed by relevant miscellaneous pulses/diseases, deleting irrelevant ones. This would clarify laws and separate truth from falsehood. Lacking time, I record this for future revision.