凡用药处方，最宜通变，不可执滞。观仲景以麻黄汤，治太阳经发热、头痛、脉浮、无汗之伤寒；而阳
明病脉浮、无汗而喘者亦用之；太阳与阳明合病，喘而胸满者亦用之。此麻黄汤之通变也。又如桂枝汤，本治
太阳经发热、汗出之中风；而阳明病，如疟状，日晡发热，脉浮虚，宜发汗者亦用之；太阳病外证未解，脉浮
弱，当以汗解者亦用之；太阴病，脉浮可发汗者亦用之；厥阴证，下利腹胀满，身疼痛，宜攻表者亦用之。此
桂枝汤之通变也。又如小柴胡汤，本治少阳经胁痛干呕、往来寒热之伤寒；而阳明病，潮热胸胁满者亦用之；
阳明中风，脉弦浮大，腹满胁痛，不得汗，身面悉黄，潮热等证亦用之；妇人中风，续得寒热，经水适断，热
入血室，如疟状者亦用之。此小柴胡汤之通变也。由此观之，可见仲景之意，初未尝逐经执方，而立方之意，
多有言不能悉者，正神不可以言传也。所以有此法，未必有此证。有此
证，未必有此方。即仲景再生，而欲尽踵其成法，吾知其未必皆相合。即仲景复言，而欲尽吐其新方，吾知其
未必无短长。于戏！方乌足以尽变，变胡可以定方，但使学人能会仲景之意，则亦今之仲景也，又何必以仲景
之方为拘泥哉！余故曰∶用药处方，最宜通变，不当执滞也。虽然，此通变二字，盖为不能通变者设，而不知
斯道之理，又自有一定不易之要焉。苟不知要，而强借通变为谭柄，则胡猜乱道，妄议经权，反大失通变之
旨矣。○补方之制，补其虚也。凡气虚者宜补其上，人参、黄 之属是也；精虚者宜补其下，熟地、枸杞之属
是也；阳虚者宜补而兼暖，桂、附、干姜之属是也；阴虚者宜补而兼清，门冬、芍药、生地之属是也。此固阴
阳之治辨也。其有气因精而虚者，自当补精以化气；精因气而虚者，自当补气以生精。又有阳失阴而离者，不
补阴，何以收散亡之气？水失火而败者，不补火，何以苏垂寂之阴？此又阴阳相济之妙用也。故善补阳者，必
于阴中求阳，则阳得阴助，而生化无穷；善补阴者，必于阳中求阴，则阴得阳升，而泉源不竭。余故曰∶以精
气分阴阳，则阴阳不可离。以寒热分阴阳，则阴阳不可混。此又阴阳邪正之离合也。故凡阳虚多寒者，宜补以
甘温，而清润之品非所宜；阴虚多热者，宜补以甘凉，而辛燥之类不可用。○和方之制，和其不和者也。凡病
兼虚者，补而和之；兼滞者，行而和之；兼寒者，温而和之；兼热者，凉而和之。和之为义广矣。亦犹土兼四
气，其于补泻温凉之用，无所不及，务在调平元气，不失中和之为贵也。故凡阴虚于下，而精血亏损者，忌利
水；阴虚于上，而肺热干咳者，忌辛燥；阳虚于上者，忌消耗；阳虚于下者，忌沉寒；大便溏泄者，忌滑利；
表邪未解者，忌收涩；气滞者，忌闭塞；经滞者，忌寒凝。凡邪火在上者，不宜升，火得升而愈炽矣；沉寒在
下者，不宜降，阴被降而愈亡矣。诸动者，不宜再动。如火动者，忌温暖；血动者，忌辛香；汗动者，忌疏散；
神动者，忌耗伤。凡性味之不静者，皆所当慎。其
于刚暴更甚者，则在不言可知也。诸静者不宜再静，如沉微细弱者，脉之静也；神昏气怯者，阳之静也；肌体
清寒者，表之静也；口腹畏寒者，里之静也。凡性味之阴柔者，皆所当慎。其于沉寒更甚者，又在不言可知也。
夫阳主动，以动济动，火上添油也。不焦烂乎？阴主静，以静益静，雪上加霜也。不寂灭乎？不知此义，又何
和剂之足云。○攻方之制，攻其实也。凡攻气者，攻其聚，聚可散也。攻血者，攻其淤，淤可通也。攻其坚，
在脏者可破可培，在经者可针可灸也。攻痰者，攻其急，真实者暂宜解标，多虚者只宜求本也。但诸病之实有
微甚，用攻之法分轻重。大实者，攻之未及，可以再加；微实者，攻之大过，每因致害。凡病在阳者，不可
攻阴。病在腑者，不可攻脏。若此者邪必乘虚内陷，所谓引贼入门也。病在阴者，勿攻其阳。病在里者，勿攻
其表。若此者，病必因误而甚，所谓自撤藩蔽也。大都治宜用攻，必其邪之甚者也。其若实邪果甚，自与攻药
相宜，不必杂之补剂。盖实不嫌攻，若但略加甘滞，便相牵制。虚不嫌补，若但略加消耗，便觉相妨。所以寒
实者最不喜清，热实者最不喜暖。然实而误补，不过增病，病增者可解；虚而误攻，必先脱元，元脱者无治矣。
其或虚中有实，实中有虚，此又当酌其权宜，不在急宜攻急宜补之例。虽然，凡用攻之法，所以除凶剪暴也。
然惟必不得已乃可用之，若或有疑，须加详慎。盖攻虽去邪，无弗伤气，受益者四，受损者六，故攻之一法，
实自古仁人所深忌者，正恐其成之难，败之易耳。○散方之制，散表证也。观仲景太阳证，用麻黄汤；阳明证，
用葛根汤；少阳证，用小柴胡汤。此散表之准绳也。后世宗之，而复不能用之，在不得其意耳。盖麻黄之气峻
利而勇，凡太阳经阴邪在表者，寒毒既深，非此不达，故制用此方，非谓太阳经药，必须麻黄也。设以麻黄治
阳明、少阳之证，亦寒无不散，第恐药方太过，反伤其气，岂谓某经某药，必不可移易，亦不过分其轻重耳。
故如阳明之葛很，未有不走太阳、少阳者；少
阳之柴胡，亦未有不入太阳、阳明者。但用散之法，当知性力缓急、气味寒温之辨，用得其宜，诸经无不妙也。
如麻黄、桂枝，峻散者也；荆、防、紫苏，平散者也；辛、芷、生姜，温散者也；柴、葛、薄荷，凉散者也；
羌活、苍术，能走经去湿而散者也；升麻、川芎，能举陷上行而散者也。第邪浅者忌峻利，气弱者忌雄悍，热
多者忌温燥，寒多者忌清凉。凡热渴烦燥者喜干葛，而呕恶者忌之；寒热往来者宜柴胡，而泄泻者忌之；寒邪
在上者宜升麻、川芎，而内热火升者忌之。此性味之宜忌所当辨也。至于相配之法，则尤当知要。凡以平兼清，
自成凉散；以平兼暖，亦可温经。宜大温者，以热济热；宜大凉者，以寒济寒。此其运用之权，则毫厘进退自
有伸缩之妙，又何必胶柱刻舟，以限无穷之变哉！○寒方之制，为清火也，为除热也。夫火有阴阳，热分上
下。方书咸谓黄连清心，黄芩清肺，石斛、芍药清脾，龙胆清肝，黄柏清肾。是亦胶柱法也。凡寒凉皆能泻火，
岂有凉此而不凉彼者，但当分其轻清重浊，性力微甚，用得其宜，则善矣。夫轻清者，宜以清上；重浊者，宜
于清下。性力之浓者，能清大热；性力之缓者，能清微热。以攻而用者，去实郁之热；以利而用者，去癃闭之
热；以补而用者，去阴虚枯燥之热。然火之甚者，在上亦宜重浊；火之微者，在下亦可轻清。夫宜凉之热，皆
实热也。实热在下，自宜清利；实热在上，不可升提。盖火本属阳，宜从阴治，从阴者宜降，升则反从阳矣。
《经》曰∶高者抑之，义可知也。外如东垣有升阳散火之法，此以表邪生热者设，不得与伏火内炎者并论。
○热方之制，为除寒也。夫寒之为病，有寒邪犯于肌表者，此皆外来之寒，人所易知。至于本来之寒，生于无
形无响之间，人之病此者最多，人之知此者最少。丹溪曰∶气有余，便是火。余续之曰∶气不足，便是寒。夫
今人之气有余者，能十中之几？其有或因禀受，或因丧败，以致阳气不足者，多见寒从中生，而阳衰之病无所
不致。第其由来者渐，形见者微，当其未
觉，孰为之意？及其既甚，始知治难。矧庸医无识，每以假热为真火，因复毙于无形无响者，又不知其几。故
惟高明之士，常以阳衰根本为忧，此热方之不可不知也。然用热之法，尚有其要。以散兼温，散寒邪也；以行
兼温，行寒滞也；以补兼温，补虚寒也。第多汗者忌姜，姜能散也；失血者忌桂，桂动血也；气短怯者忌故纸，
故纸降气也。凡气香者，皆不利于气虚；味辛者，多不利于血证。是用热之概也。至于附子之辨，今之用者，
必待势不可为然后用之，不知回阳之功，当用于阳气将去之际，可望挽回。若用于既去之后，死灰不可复然矣。
但附子性悍，独任为难，必得人参、熟地、炙甘草之类以制其刚，而济其勇，无往不利矣。○固方之制，固其
泄也。如久嗽为喘，而气泄于上者，宜固其肺；久遗成淋，而精脱于下者，宜固其肾。小水不禁者，宜固其膀
胱；大便不禁者，宜固其肠脏；汗泄不止者，宜固其皮毛；血泄不止者，宜固其营卫。凡因寒而泄者，当固之
以热；因热而泄者，当固之以寒。总之，在上在表者，皆宜固气；在下在里者，皆宜固精。然虚者可固，实者
不可固。久者可固，暴者不可固。当固不固，则沧海亦将竭；不当固而固，则闭门留寇也。○因方之制，因其
可因者也。凡病有相同者，皆可按证而用之。如痈毒之起，肿可敷也；蛇虫之患，毒可解也；汤火伤其肌肤，
热可散也；跌打伤其筋骨，断可续也。凡此之类，皆因证而可药者也。然因中有不可因者，又在乎证同而因不
同耳。盖人之虚、实、寒、热，各有不齐，表、里、阴、阳，治当分类。故有宜于此，而不宜于彼者。有同于
表，而不同于里者。病虽相类，不可谓因方之类尽可因之而用也。因之为用，有因标者，有因本者，勿因此因
字，而误认因方之义。（《景岳全书》）
凡事最忌耳食，所谓道听而途说也。如治浮火，当引火归元。用八味丸，乃指肾脏虚寒，火不能纳，非治
实火及别脏之火也。如类中风用地黄饮子，乃治少阴纯虚之痱证，非治风火痰厥之中
风也。如暑月用大顺散，乃治夏日贪凉中寒之证，非治暑热正病也。如大便不通用芦荟丸，乃治广肠坚结，诸
药不效之病，非治津液枯燥之证也。近人耳闻有此数方，并不细审病因，惘然施用，受祸必烈。（《兰台轨范》）
凡用方不分君臣佐使，头绪纷杂，率意妄施，药与病迥不相当，医之罪也。（《医门法律》）
凡用药处方，最适宜灵活变通，不可固执拘泥。看张仲景用麻黄汤（Mahuang Tang, Ephedra Decoction），治疗太阳经（Taiyang Channel）发热、头痛、脉浮、无汗的伤寒病；而阳明病（Yangming Disease）出现脉浮、无汗且气喘的，也使用它；太阳与阳明合病（Combined Disease of Taiyang and Yangming），出现气喘且胸满的，也使用它。这是麻黄汤的灵活变通。又如桂枝汤（Guizhi Tang, Cinnamon Twig Decoction），原本治疗太阳经发热、汗出的中风病；而阳明病，症状像疟疾，下午申时发热，脉浮虚，应当发汗的，也使用它；太阳病外证未解，脉浮弱，应当以发汗法解除的，也使用它；太阴病（Taiyin Disease），脉浮可以发汗的，也使用它；厥阴病（Jueyin Disease），下利腹胀满，身体疼痛，应当攻表的，也使用它。这是桂枝汤的灵活变通。又如小柴胡汤（Xiaochaihu Tang, Minor Bupleurum Decoction），原本治疗少阳经（Shaoyang Channel）胁痛干呕、往来寒热（Alternating Chills and Fever）的伤寒病；而阳明病，潮热（Tidal Fever）、胸胁满闷的，也使用它；阳明中风，脉弦浮大，腹满胁痛，不能出汗，全身面目发黄，潮热等症状，也使用它；妇人中风，持续出现寒热，月经适断，热入血室（Heat Entering the Blood Chamber），症状像疟疾的，也使用它。这是小柴胡汤的灵活变通。由此看来，可见张仲景的本意，从未曾拘泥于某经只用某方，他立方之意，多有言语无法完全表达的，这正是神妙的道理无法仅靠言传来传达。所以有此法，未必对应此证；有此证，未必对应此方。即使张仲景再生，想要完全遵循他的成法，我知道未必都能契合。即使张仲景复生，想要完全抛弃他的新方，我知道也未必没有长短优劣。唉！方剂怎么足以穷尽变化？变化又怎能被固定的方剂所限制？只要学医的人能领会张仲景的心意，那么也就是当今的张仲景了，又何必拘泥于张仲景的方剂呢！所以我常说：用药处方，最宜灵活变通，不应当固执拘泥。虽然如此，这“通变”二字，是给那些不能通变的人设立的，然而不知道医学的道理，自有其一定不变的要领。如果不知道要领，却强行借用通变作为谈资，那就是胡乱猜测、违背正道，妄议经权（经典与权变），反而大大失去了通变的宗旨了。○补方（Tonifying Formulas）的制定，是为了补益虚弱。凡是气虚者，适宜补其上焦，如人参（Ginseng Radix）、黄芪（Astragali Radix）之类的药材；精虚者，适宜补其下焦，如熟地黄（Rehmanniae Radix Preparata）、枸杞子（Lycii Fructus）之类的药材；阳虚者，适宜补益兼以温暖，如肉桂（Cinnamomi Cortex）、附子（Aconiti Lateralis Radix Preparata）、干姜（Zingiberis Rhizoma）之类的药材；阴虚者，适宜补益兼以清润，如麦冬（Ophiopogonis Radix）、芍药（Paeoniae Radix）、生地黄（Rehmanniae Radix）之类的药材。这固然是阴阳治疗的辨别。其中有因精亏导致气虚的，自然应当补精以化气；因气虚导致精亏的，自然应当补气以生精。又有阳气失去阴液依附而离散者，不补阴，怎么能收敛散亡之气？水液失去火气温煦而败坏者，不补火，怎么能复苏将熄之阴？这又是阴阳相互济助的妙用。所以善于补阳的人，必定在补阴中求取阳气，那么阳气得到阴液的资助，而生化无穷；善于补阴的人，必定在补阳中求取阴液，那么阴液得到阳气的升发，而泉源不竭。所以我常说：以精气来分阴阳，则阴阳不可分离；以寒热来分阴阳，则阴阳不可混淆。这又是阴阳邪正离合的道理。所以凡是阳虚多寒者，适宜用甘温之品补益，而清润的药物就不适宜；阴虚多热者，适宜用甘凉之品补益，而辛燥的药物就不可使用。○和方（Harmonizing Formulas）的制定，是为了调和不和的状态。凡是疾病兼有虚损的，补益而调和它；兼有滞涩的，行气而调和它；兼有寒邪的，温里而调和它；兼有热邪的，清热而调和它。和法的含义很广。也如同土性兼有四气，它在补泻温凉的作用上，无所不及，务必在于调平元气，不失中和之道为贵。所以凡是下焦阴虚，而精血亏损的，忌用利水药；上焦阴虚，而肺热干咳的，忌用辛燥药；上焦阳虚的，忌用消耗元气的药；下焦阳虚的，忌用沉寒药；大便溏泄的，忌用滑利药；表邪未解的，忌用收涩药；气滞的，忌用闭塞药；经血滞涩的，忌用寒凝药。凡是邪火在上焦的，不宜升提，火得升提而更加炽盛；沉寒在下焦的，不宜降下，阴气得降下而更加消亡。凡是动证的，不宜再使其动。如火动者，忌用温暖药；血动者，忌用辛香药；汗动者，忌用疏散药；神动者，忌用耗伤药。凡是性味不宁静的药物，都应当谨慎。其中刚烈暴烈的更甚，那就在不言中可知了。凡是静证的，不宜再使其静，如脉象沉微细弱，是脉之静；神昏气怯，是阳之静；肌体清寒，是表之静；口腹畏寒，是里之静。凡是性味阴柔的药物，都应当谨慎。其中沉寒更甚的，又在不言中可知了。阳气主动，以动助动，是火上浇油啊，难道不会焦烂吗？阴气主静，以静益静，是雪上加霜啊，难道不会寂灭吗？不懂得这个道理，又说什么和剂呢。○攻方（Attacking Formulas）的制定，是为了攻逐实邪。凡是攻气者，攻其聚结，聚结可以消散；攻血者，攻其瘀血，瘀血可以通畅；攻其坚硬，在脏器的可以破坚或培补，在经络的可以针刺或艾灸。攻痰者，攻其急症，实证暂时适宜解标，多虚者只适宜求本。但各种疾病的实邪有轻微和严重之分，使用攻法要分轻重。大实者，攻伐若力度不够，可以再增加；微实者，攻伐若太过，往往会导致伤害。凡是病在阳分的，不可攻阴分；病在腑的，不可攻脏。像这样，邪气必定乘虚内陷，所谓引贼入门。病在阴分的，不要攻阳分；病在里的，不要攻表。像这样，病情必定因为误治而加重，所谓自撤藩蔽。大都治疗适宜用攻法，必须是邪气很严重的情况。如果实邪确实严重，自然与攻药相适宜，不必掺杂补剂。因为实证不忌讳攻伐，如果稍微加一点甘缓壅滞的药，就会相互牵制。虚证不忌讳补益，如果稍微加一点消耗的药，就会觉得相妨碍。所以寒实证最不喜清热药，热实证最不喜温补药。然而实证误用补法，不过是增加病情，病情增加的还可以解救；虚证误用攻法，必先脱失元气，元气脱失的就无法治疗了。或者虚中有实，实中有虚，这又应当斟酌权宜，不在急于攻或急于补的常规之内。虽然如此，凡是使用攻法，是为了除凶剪暴。然而只有在万不得已的情况下才可使用，如果有疑虑，必须详细审慎。因为攻法虽然去邪，无不损伤正气，受益者四成，受损者六成，所以攻法这一方法，实在是自古仁人深为忌讳的，正是担心它成功难，失败易罢了。○散方（Dispersing Formulas）的制定，是为了解散表证。看张仲景太阳证，用麻黄汤；阳明证，用葛根汤（Ge Gen Tang, Puerariae Lobatae Radix Decoction）；少阳证，用小柴胡汤。这是解散表证的准则。后世效法它，却又不能运用得当，是因为没有得到其中的心意。大概麻黄的药气峻猛锋利而勇健，凡是太阳经阴邪在表的，寒毒既深，不用此药不能达表，所以制定这个方子，并不是说太阳经的药，必须用麻黄。假如用麻黄治疗阳明、少阳的证候，寒气也没有不散去的，只是恐怕药力太过，反而损伤正气，难道是说某经某药，必不可移易吗？也不过是分清轻重罢了。所以像阳明的葛根，没有不走太阳、少阳的；少阳的柴胡（Bupleuri Radix），也没有不入太阳、阳明的。只是使用散法，应当知道药性的缓急、气味的寒温之辨别，用得适宜，各经无不妙用。如麻黄、桂枝，是峻猛的散剂；荆芥（Schizonepetae Herba）、防风（Saposhnikoviae Radix）、紫苏（Perillae Folium），是平和的散剂；辛夷（Magnoliae Flos）、白芷（Angelicae Dahuricae Radix）、生姜（Zingiberis Recens Rhizoma），是温散的药剂；柴胡、葛根、薄荷（Menthae Haplocalycis Herba），是凉散的药剂；羌活（Notopterygii Rhizoma et Radix）、苍术（Atractylodis Rhizoma），是能走经络祛湿而散的药剂；升麻（ Cimicifugae Rhizoma）、川芎（Chuanxiong Rhizoma），能举陷上行而散的药剂。只是邪气浅薄的忌用峻利药，正气虚弱的忌用雄悍药，热多的忌用温燥药，寒多的忌用清凉药。凡是热渴烦躁的喜欢葛根，而呕吐恶心的忌用葛根；寒热往来的适宜柴胡，而泄泻的忌用柴胡；寒邪在上焦的适宜升麻、川芎，而内热火升的忌用。这是性味适宜与禁忌应当辨别的。至于配伍的方法，则更应当知晓要领。凡是平和兼清热的，自然成为凉散；平和兼温暖的，也可以温经。适宜大温的，以热助热；适宜大凉的，以寒助寒。这其中的运用权变，毫厘进退自然有伸缩的妙处，又何必胶柱鼓瑟、刻舟求剑，来限制无穷的变化呢！○寒方（Cold Formulas）的制定，是为了清火，为了除热。火有阴阳，热分上下。医书都说黄连（Coptidis Rhizoma）清心，黄芩（Scutellariae Radix）清肺，石斛（Dendrobii Caulis）、芍药清脾，龙胆（Gentianae Radix）清肝，黄柏（Phellodendri Cortex）清肾。这也是胶柱鼓瑟的方法。凡是寒凉药都能泻火，哪有凉这里而不凉那里的道理，只应当分辨其轻清重浊，药力的微甚，用得适宜，就好了。轻清的药，适宜清上焦；重浊的药，适宜清下焦。药力浓烈的，能清大热；药力缓和的，能清微热。以攻法用的，去除实郁之热；以利法用的，去除癃闭之热；以补法用的，去除阴虚枯燥之热。然而火邪严重的，在上焦也宜用重浊药；火邪轻微的，在下焦也可用轻清药。适宜用凉药的，都是实热。实热在下，自然适宜清利；实热在上，不可升提。因为火本属阳，适宜从阴治，从阴治适宜降，升则反而从阳了。《内经》说：高者抑之，义理可知。另外如李东垣有升阳散火之法，这是为表邪生热而设的，不能与伏火内炎的情况并论。○热方（Hot Formulas）的制定，是为了除寒。寒这种病，有寒邪侵犯肌表的，这都是外来之寒，人们容易知道。至于本来的寒，生于无形无响之间，人患这种病的很多，知道这种病的很少。朱丹溪说：气有余，便是火。我接着说：气不足，便是寒。现在人的气有余的，能有几个？那些有的因为禀赋，有的因为损耗，导致阳气不足的，多见寒从中生，而阳衰的病无所不至。只是它的由来是逐渐形成的，表现的症状细微，当它尚未察觉时，谁会在意？等到它已经很严重时，才知道治疗困难。况且庸医无识，常常把假热当作真火，因此又死于无形无响的寒证，不知有多少。所以只有高明之士，常以阳衰根本为忧，这就是热方不可不知的原因。然而使用热法，还有其要领。以散法兼温法，是散寒邪；以行法兼温法，是行寒滞；以补法兼温法，是补虚寒。只是多汗者忌用生姜，生姜能发散；失血者忌用桂枝，桂枝动血；气短怯弱者忌用补骨脂（Psoraleae Fructus），补骨脂降气。凡是气味香的，都不利于气虚；味道辛的，多不利于血证。这是用热法的概况。至于附子的辨别，现在使用的人，一定要等到形势不可挽回时才使用，不知道回阳之功，应当在阳气将去之际使用，有望挽回。如果用在阳气已去之后，死灰不可能复燃。但附子性猛烈，单独使用很难，必须得到人参、熟地黄、炙甘草（Glycyrrhizae Radix et Rhizoma Preparata cum Melle）之类来制约它的刚烈，而辅助它的勇健，就没有不利的了。○固方（Consolidating Formulas）的制定，是为了固摄泄脱。如久嗽致喘，而气泄于上焦的，适宜固摄肺；久遗成淋，而精脱于下焦的，适宜固摄肾。小便不禁的，适宜固摄膀胱；大便不禁的，适宜固摄肠脏；汗泄不止的，适宜固摄皮毛；血泄不止的，适宜固摄营卫。凡是因寒而泄的，应当用热药固摄；因热而泄的，应当用寒药固摄。总之，在上在表的，都适宜固气；在下在里的，都适宜固精。然而虚证可固，实证不可固；久病可固，暴病不可固。应当固而不固，则沧海也将枯竭；不应当固而固，则是闭门留寇。○因方（Following Formulas）的制定，是根据病情可因势利导的。凡是疾病有相同的，都可以按证而用。如痈毒发作，肿胀可以外敷；蛇虫咬伤，毒邪可以解除；汤火烫伤肌肤，热邪可以消散；跌打损伤筋骨，断裂可以续接。凡是这类，都是根据证候可以用药的。然而因中有不可因的，又在于证同而因不同。人的虚、实、寒、热，各有不齐，表、里、阴、阳，治疗应当分类。所以有适宜于此，而不适宜于彼的。有同于表，而不同于里的。病虽相似，不能说因方的类别都可以因循使用。因的作用，有因标的，有因本的，不要因为“因”字，而误解因方的意义。（出自《景岳全书》）凡事最忌讳道听途说，所谓耳食之言。如治疗浮火，应当引火归元。使用八味丸（Ba Wei Wan, Eight-Ingredient Pill with Rehmannia），是指肾脏虚寒，火不能纳，不是治疗实火及别脏之火。如类中风用地黄饮子（Di Huang Yin Zi, Rehmannia Decoction），是治疗少阴纯虚的痱证，不是治疗风火痰厥的中风。如暑月用大顺散（Da Shun San, Great Harmony Powder），是治疗夏日贪凉中寒的证候，不是治疗暑热正病。如大便不通用芦荟丸（Lu Hui Wan, Aloe Pill），是治疗广肠坚结，诸药无效的病，不是治疗津液枯燥的证候。近人耳闻有此数方，并不细审病因，茫然施用，受祸必然猛烈。（出自《兰台轨范》）凡是用方不分君臣佐使，头绪纷杂，率意妄施，药与病迥然不相当，是医生的罪过。（出自《医门法律》）
In prescribing medications, one must be flexible and adaptable, avoiding rigidity. Consider Zhang Zhongjing's use of Mahuang Tang (Ephedra Decoction) to treat Shaohang disease (Cold Damage) of the Taiyang channel characterized by fever, headache, floating pulse, and anhidrosis; yet it is also used for Yangming disease presenting with a floating pulse, anhidrosis, and wheezing; and for combined diseases of Taiyang and Yangming presenting with wheezing and chest fullness. This illustrates the adaptability of Mahuang Tang. Similarly, Guizhi Tang (Cinnamon Twig Decoction), originally intended for Wind-strike of the Taiyang channel with fever and sweating, is also used for Yangming disease resembling malaria with afternoon tidal fever and a floating-deficient pulse requiring diaphoresis; for Taiyang disease where exterior symptoms remain unresolved with a floating-weak pulse requiring diaphoresis; for Taiyin disease with a floating pulse suitable for diaphoresis; and for Jueyin disease with diarrhea, abdominal fullness, and body pain requiring exterior attack. This illustrates the adaptability of Guizhi Tang. Likewise, Xiaochaihu Tang (Minor Bupleurum Decoction), originally for Shaoyang channel Cold Damage with hypochondriac pain, dry retching, and alternating chills and fever, is also used for Yangming disease with tidal fever and chest-hypochondriac fullness; for Yangming Wind-strike with wiry-floating-large pulse, abdominal fullness, hypochondriac pain, inability to sweat, generalized jaundice, and tidal fever; and for women with Wind-strike who develop persistent chills and fever after menstruation ceases, indicating Heat entering the Blood Chamber resembling malaria. This illustrates the adaptability of Xiaochaihu Tang. From this, we see that Zhang Zhongjing never rigidly adhered to specific formulas for specific channels. The intent behind his prescriptions often transcends verbal description, reflecting a divine principle that cannot be fully conveyed by words. Thus, having a method does not guarantee a corresponding syndrome; having a syndrome does not guarantee a corresponding formula. Even if Zhang Zhongjing were reborn, attempting to strictly follow his established methods, I know they would not always fit. Even if he spoke again, attempting to completely discard his new formulas, I know there would still be merits and flaws. Alas! How can formulas exhaust all variations? How can variations be confined to fixed formulas? If practitioners can grasp the spirit of Zhang Zhongjing, they become Zhang Zhongjing of their own time, and why should they be bound by his formulas? Therefore, I say: Prescribing requires flexibility and adaptation, not rigidity. However, these two words "adaptability" are set for those who cannot adapt. Yet, the principles of this art have their own unchanging essentials. If one ignores these essentials and uses "adaptability" as a pretext for speculation, it leads to reckless deviation from the correct path, misinterpreting classics and expediency, thereby losing the true meaning of adaptability.
Tonifying Formulas are designed to tonify deficiency. For Qi deficiency, tonification should target the upper jiao, using herbs like Renshen (Ginseng Root) and Huangqi (Astragalus Root). For Essence deficiency, tonification should target the lower jiao, using herbs like Shudihuang (Prepared Rehmannia Root) and Gouqizi (Goji Berry). For Yang deficiency, tonification should include warming agents like Rougui (Cinnamon Bark), Fuzi (Prepared Aconite Lateral Root), and Ganjiang (Dried Ginger). For Yin deficiency, tonification should include clearing and moistening agents like Maidong (Ophiopogon Root), Shaoyao (Peony Root), and Shengdihuang (Fresh Rehmannia Root). This distinguishes Yin and Yang treatments. If Qi deficiency stems from Essence deficiency, one must tonify Essence to generate Qi; if Essence deficiency stems from Qi deficiency, one must tonify Qi to generate Essence. If Yang loses its Yin anchor and scatters, how can scattered Qi be gathered without tonifying Yin? If Water fails due to lack of Fire warmth, how can dying Yin revive without tonifying Fire? This is the subtle application of mutual assistance between Yin and Yang. Thus, those skilled in tonifying Yang must seek Yang within Yin tonification, so Yang receives Yin support and generation becomes endless. Those skilled in tonifying Yin must seek Yin within Yang tonification, so Yin receives Yang ascent and sources remain inexhaustible. Therefore, I say: Dividing Yin and Yang by Qi and Essence means they cannot be separated; dividing them by Cold and Heat means they cannot be confused. This addresses the separation and union of pathogens and healthy Qi. Thus, for Yang deficiency with much Cold, sweet-warm tonics are appropriate, while cooling-moistening agents are unsuitable. For Yin deficiency with much Heat, sweet-cool tonics are appropriate, while acrid-dry agents are contraindicated.
Harmonizing Formulas are designed to harmonize disharmony. For diseases with deficiency, harmonize by tonifying; with stagnation, harmonize by moving; with Cold, harmonize by warming; with Heat, harmonize by cooling. The concept of "Harmonizing" is broad, akin to Earth accommodating all four natures, covering tonification, purging, warming, and cooling, aiming to balance Yuan Qi and maintain the Golden Mean. Thus, for lower Yin deficiency with Essence-Blood loss, avoid diuretics; for upper Yin deficiency with Lung Heat dry cough, avoid acrid-dry agents; for upper Yang deficiency, avoid agents that consume Qi; for lower Yang deficiency, avoid sinking-cold agents; for loose stools, avoid slippery agents; for unresolved exterior pathogens, avoid astringents; for Qi stagnation, avoid obstructive agents; for menstrual stasis, avoid cold-congealing agents. For pathogenic Fire in the upper jiao, avoid ascending agents, as Fire will flare up; for Sinking-Cold in the lower jiao, avoid descending agents, as Yin will further deplete. For conditions involving movement, avoid further agitation: for Fire agitation, avoid warming; for Blood agitation, avoid acrid-aromatics; for Sweat agitation, avoid dispersing; for Spirit agitation, avoid consuming agents. All agents with unstable natures/flavors require caution. Those more violent are self-evidently dangerous. For conditions involving stillness, avoid further stillness: such as deep-thin-slow-weak pulses (Stillness of Pulse), confusion and cowardice (Stillness of Yang), cold body surface (Stillness of Exterior), and aversion to cold in mouth/abdomen (Stillness of Interior). All Yin-soft agents require caution. Those with severe sinking-cold are self-evidently dangerous. Yang governs movement; assisting movement with movement is adding oil to fire—will it not burn? Yin governs stillness; assisting stillness with stillness is adding frost to snow—will it not perish? Without understanding this, how can one speak of Harmonizing Formulas?
Attacking Formulas are designed to attack excess. To attack Qi, attack its aggregation, which can be dispersed. To attack Blood, attack its stasis, which can be unblocked. To attack hardness, break or tonify Zang organs, or use acupuncture/moxibustion on meridians. To attack Phlegm, address urgency: acute excess cases may need temporary symptom relief, while deficient cases need root treatment. Excess varies in severity; attacking methods vary in intensity. For severe excess, insufficient attack can be increased; for mild excess, excessive attack causes harm. Do not attack Yin when disease is in Yang; do not attack Zang when disease is in Fu. Otherwise, pathogens enter void spaces, inviting thieves indoors. Do not attack Yang when disease is in Yin; do not attack Exterior when disease is in Interior. Otherwise, illness worsens due to error, removing one's own defenses. Attacking is suitable only for severe pathogens. If excess is genuine, attacking drugs are suitable without mixing tonics, as excess tolerates attack but resists cloying tonics. Deficiency tolerates tonification but resists draining agents. Cold-excess dislikes clearing; Heat-excess dislikes warming. Misusing tonics for excess merely increases illness, which can be resolved; misusing attacking for deficiency depletes Yuan Qi, which is incurable. For mixed deficiency-excess, weigh options carefully, beyond simple immediate attack or tonification. Attacking removes凶暴 (violence) but inevitably damages Qi; benefits are 40%, damage is 60%. Thus, ancient benevolent physicians feared this method due to difficulty in success and ease of failure.
Dispersing Formulas are designed to resolve exterior syndromes. Zhang Zhongjing used Mahuang Tang for Taiyang, Ge Gen Tang (Pueraria Decoction) for Yangming, and Xiaochaihu Tang for Shaoyang. This is the standard for dispersing exterior. Later generations followed but failed to apply correctly due to misunderstanding. Mahuang has fierce, penetrating power, necessary for deep-seated Cold-Damp in Taiyang exterior. It is not exclusive to Taiyang; using it for Yangming/Shaoyang disperses Cold but risks damaging Qi due to excessive strength. Ge Gen acts on Taiyang/Shaoyang; Chaihu (Bupleurum Root) enters Taiyang/Yangming. When using dispersing methods, distinguish speed of action and temperature/nature. Mahuang/Guizhi are fierce dispersants; Jingjie (Schizonepeta), Fangfeng (Saposhnikovia), Zisu (Perilla Leaf) are mild; Xinyi (Magnolia Bud), Baizhi (Dahurian Angelica), Shengjiang (Fresh Ginger) are warm; Chaihu, Ge Gen, Bohe (Mint) are cool; Qianghuo (Notopterygium), Cangzhu (Atractylodes) disperse dampness via meridians; Shengma (Cimicifuga), Chuanxiong (Ligusticum) raise sinking and disperse. Avoid fierce agents for shallow pathogens; avoid strong agents for weak Qi; avoid warm-dry for much Heat; avoid cool for much Cold. Ge Gen suits heat-thirst but harms vomiting; Chaihu suits alternating chills/fever but harms diarrhea; Shengma/Chuanxiong suit upper Cold but harm internal Fire rising. Pairings matter: mild + cool = cool dispersion; mild + warm = warm meridian. Great warmth needs heat-assisting heat; great coolness needs cold-assisting cold. Flexibility allows infinite variation, avoiding rigid adherence.
Cold Formulas are designed to clear Fire and remove Heat. Fire has Yin/Yang; Heat divides into Upper/Lower. Books state Huanglian (Coptis) clears Heart, Huangqin (Scutellaria) clears Lung, Shihu (Dendrobium)/Shaoyao clear Spleen, Longdan (Gentian) clears Liver, Huangbai (Phellodendron) clears Kidney. This is rigid thinking. All cooling herbs drain Fire; distinction lies in light/heavy nature and potency. Light/clear clears Upper; heavy/turbid clears Lower. Strong potency clears major Heat; mild potency clears minor Heat. Used as attack for stagnant Heat; used as drainage for retention Heat; used as tonification for Yin-deficiency dryness. Severe Fire in Upper may need heavy agents; minor Fire in Lower may need light agents. Suitable cooling treats Excess Heat. Excess Heat in Lower needs clearing/drainage; Excess Heat in Upper must not be ascended. Fire is Yang, treated via Yin (descending); ascending makes it Yang. The Classic says: "Suppress what is high." Li Dongyuan's "Ascending Yang to Disperse Fire" applies only to exterior-pathogen generated Heat, not internal latent Fire.
Hot Formulas are designed to remove Cold. Cold invading muscle/skin is external and known. Innate Cold arises invisibly; many suffer it, few know it. Zhu Danxi said: "Excess Qi is Fire." I add: "Deficient Qi is Cold." Few have excess Qi today. Many have deficient Yang due to constitution or depletion, causing internal Cold and various Yang-depletion diseases. Onset is gradual, signs subtle; ignored until severe. Ignorant doctors mistake false Heat for true Fire, killing patients with invisible Cold. Only wise physicians worry about Yang-depletion root, hence knowing Hot Formulas is vital. Using Heat has essentials: Dispersing + Warming dispels Cold pathogens; Moving + Warming moves Cold stagnation; Tonifying + Warming tonifies Deficient Cold. Sweaters avoid Jiang (Ginger) as it disperses; Bleeders avoid Guizhi (Cinnamon Twig) as it moves Blood; Short-of-breath cowards avoid Gubuzi (Psoralea Fruit) as it descends Qi. Aromatic herbs harm Qi deficiency; Acrid herbs harm Blood disorders. Regarding Fuzi (Aconite): used only when desperate. Its function to restore Yang works best when Yang is about to depart, not after it has left. Fuzi is fierce; alone it is hard to manage. Must be paired with Renshen, Shudihuang, Zhigancao (Honey-fried Licorice) to control its harshness and aid its bravery.
Consolidating Formulas are designed to secure leakage. Chronic cough leading to asthma with Qi leaking upward: consolidate Lung. Chronic spermatorrhea leading to strangury with Essence leaking downward: consolidate Kidney. Incontinence of urine: consolidate Bladder. Incontinence of stool: consolidate Intestines. Unstopping sweating: consolidate Skin/Hair. Unstopping bleeding: consolidate Ying/Wei. Leakage due to Cold: consolidate with Heat. Leakage due to Heat: consolidate with Cold. Upper/Exterior: consolidate Qi. Lower/Interior: consolidate Essence. Deficiency can be consolidated; Excess cannot. Chronic can be consolidated; Acute cannot. Failing to consolidate when needed drains the ocean; consolidating when inappropriate locks the thief inside.
Following Formulas are designed to follow indications. Similar diseases can be treated similarly. Abscess swelling: apply poultice. Snake/insect bite: resolve toxin. Scald/burn: dissipate Heat. Fracture/dislocation: reconnect bones. These are drug treatments based on symptoms. However, "following" has limits: same symptoms, different causes. Patients vary in Deficiency/Excess/Cold/Heat, Exterior/Interior/Yin/Yang; treatments must be classified. What suits one may not suit another. Similar exterior may differ in interior. Similar diseases do not mean all "Following Formulas" are applicable. "Following" can refer to following symptoms (biao) or root (ben). Do not misunderstand the term "Following Formula." (From *Jingyue Quanshu*)
Most beware of hearsay, "roadside talk." Treating floating Fire requires guiding Fire back to its source. Ba Wei Wan (Eight-Ingredient Pill) is for Kidney deficiency-cold where Fire cannot be anchored, not for Excess Fire or Fire in other organs. Di Huang Yin Zi (Rehmannia Decoction) for apoplexy-like stroke treats Shaoyin pure deficiency Fei syndrome, not Wind-Fire-Phlegm stroke. Da Shun San (Great Harmony Powder) in summer treats Cold from overcooling, not Summerheat proper. Lu Hui Wan (Aloe Pill) for constipation treats hard fecal impaction resistant to other drugs, not dryness of fluids. Moderns hear of these formulas, fail to examine causes, use blindly, and suffer severe consequences. (From *Lantai Guifan*)
Prescribing without distinguishing Sovereign, Minister, Assistant, Courier roles, resulting in chaos and arbitrary administration, where medicine does not match disease, is the doctor's fault. (From *Yimen Falü*)