按傩为古礼。疫之由来尚矣。奈何仲景伤寒。书非全璧。止言温病热病。并无片
言及疫。是以后人无善治之法。惟近世喻嘉言、吴又可、张景岳辈。可谓论切治
详。发前人所未发。但景岳宜于汗。又可宜于下。嘉言又宜于芳香逐秽。夫三子
皆名家。何治法之悬绝若此。要知三子之治法皆当。顾其所治之疫。各有不同
耳。景岳所论之疫。即六淫之邪。非时之气。其感同于伤寒。故每以伤寒并提。而
以汗为主。欲尽汗法之妙。景岳书。精切无遗。又可所论之疫。是热淫之气。从口
鼻吸入。伏于膜原。膜原为半表半里之界。其邪非汗所能达。故有不可强汗峻
汗之戒。附胃最近。入里尤速。故有急下屡下之法。欲究疫邪传变之情。惟又可论最为详尽。然又可所
论之疫。是四时之常疫。即俗名时气症也。若嘉言所论之疫。乃由于兵荒之后。因病致死。病气尸气
混合天地不正之气。更兼春夏温热暑湿之邪交结互蒸。人在气交中。无隙可避。由是沿门阖境。传
染无休。而为两间之大疫。其秽恶之气。都从口鼻吸入。直行中道。流布三焦。非表非里。汗之不解。
下之仍留。故以芳香逐秽为主。而以解毒兼之。是三子之治。各合其宜。不得执此而议彼也。兹于是症。
亦参三法为治。而分为两途。盖汗与下。即同伤寒表里之治。而逐秽解毒一法。乃疫邪匿伏三焦。非表
非里之治也。分列于左。治疫之大法得矣。
邵评∶景岳所论疫症。是三时感冒。非其时而有其气。名为三时寒疫。邪由肌毒而入。故同伤寒
治而先用汗法。若又可所论疫症。是湿温痧暑热邪。从口鼻吸受。伏于膜原。膜原者。脾与胃以膜相联。
为脾胃半表半里之界。邪伏于此。入胃最速。邪既在胃。故以下法为治。此是温热湿浊之邪袭入
六经。而传阳明胃腑
是四时之常疫。即湿温岚瘴时气之症。与毒疠天行瘟疫之病自是两种。截然不同。景岳所言。是即受
温热。邪已入胃。故景岳主汗。而又可主下也。此二者可从足经。同伤寒论治。分为一途。至嘉言
所论。是真瘟疫大病。乃天地不正之气。恶毒瘴疠。合病气口气。交结互蒸。人受其气。由口鼻吸入。
直行中道。流布三焦。最多闭结。故用芳香逐秽。解毒开化之法。此毒厉疫邪。与前二症各殊。不同伤
寒治法。分逐秽解毒。合行一途。为两大法门也。瘟疫大病。别有一种厉毒之气。极易传染。故每
病一家长幼相似。甚则沿门阖境。传染不休也。三子论治不同。
各有其症。当随症审察。合宜而用。不可拘执一说也。
长幼传染。众人一般。此疫气流行。俗名时气是也。乃天地秽恶之气。都从口鼻吸入。然有兼六淫者。
有不兼六淫者。有入足经而为表里者。有入手经而忌汗下者。当分途而治。其辨在舌。
邵评∶六淫者。风寒暑湿燥火六气之邪。此四时之常气也。大疫发时。或挟寒。或挟暑。所谓兼六淫
也。总之。纯是疠疫为病。当分邪从肌表而受。则入足经。可用
下汗法。邪由口鼻而受。则入手经。宜宗三焦立法。从心营肺卫施治。忌用汗下。
凡舌苔由白而黄。由黄而黑者。疫邪由表达里也。宜汗下法。
邵评∶邪在表则舌白。入里则舌黄。入腑热深则舌黑。邪在足经。分表里而用汗下之法。
舌苔由白而变鲜红者。疫邪由卫及营。不入足经而入手经也。忌汗下。宜逐秽解毒。清泄营分。（新法）
邵评∶邪在肺卫则舌白。入心营则舌红。传入心包。则鲜红起刺。邪在手经。宗心
卫。辨明上中下三焦而施治。忌用足经汗下之法。
傩是古代的礼仪。瘟疫的起源已经很久了。为什么张仲景的《伤寒论》这本书并不完美？它只提到了温病和热病，完全没有提及瘟疫。因此后人没有好的治疗方法。只有近代的喻嘉言、吴又可、张景岳等人，他们的论述切实、治疗详细，提出了前人未曾发现的问题。但是张景岳适宜用发汗法，吴又可适宜用泻下法，喻嘉言又适宜用芳香药物驱除秽浊之气。这三位都是名医，为什么治疗方法差异如此之大呢？要知道这三位的治疗方法都是恰当的，只是他们所治疗的瘟疫类型各不相同罢了。
张景岳所论述的瘟疫，就是六淫（风、寒、暑、湿、燥、火六种外感病邪）之邪，非时之气（不合季节的气候），其感受与伤寒相同，所以常常将二者并列提出，并以发汗法为主，想要充分发挥发汗法的妙用。张景岳的书籍，精辟确切，毫无遗漏。
吴又可所论述的瘟疫，是热淫之气（过盛的热邪），从口鼻吸入，潜伏在膜原（半表半里的部位）。膜原是半表半里的界限，邪气不在表也不在里，所以不是发汗法所能达到的，因此有不可强行发汗、峻猛发汗的戒律。胃腑离膜原最近，邪气入里特别迅速，所以有急下、屡下（多次使用泻下法）的方法。想要探究瘟疫邪气传变的规律，只有吴又可的论述最为详尽。然而吴又可所论述的瘟疫，是四季常见的普通瘟疫，也就是俗名“时气症”的疾病。
至于喻嘉言所论述的瘟疫，是由于战乱饥荒之后，因病致死，病气和尸气混合了天地间的不正之气，再加上春夏季节温热暑湿之邪交织互蒸。人们在气交之中，无处可躲避，于是沿门阖境（家家户户），传染不停，成为天地间的大瘟疫。这种秽恶之气，都从口鼻吸入，直行中道（人体中部通道），流布三焦（上焦、中焦、下焦），既不在表也不在里，发汗不能解除，泻下仍然滞留，所以以芳香药物驱除秽浊为主，兼用解毒之法。这三位的治疗，各自符合其适宜的情况，不能固执于此而议论彼非。
现在对于这种疾病，也参考这三种方法进行治疗，并分为两个途径。因为发汗和泻下，即同于伤寒表里治法；而逐秽解毒一法，是针对疫邪隐匿潜伏在三焦，既不在表也不在里的治法。分别列在下面，治疗瘟疫的大法就具备了。
邵评：张景岳所论述的瘟疫症状，是三个季节的感冒，非其时而有其气，名为“三时寒疫”。邪气由肌表毒邪而入，所以同于伤寒治疗而先用发汗法。若吴又可所论述的瘟疫症状，是湿温、痧、暑、热邪，从口鼻吸受，潜伏在膜原。膜原者，脾与胃以膜相连，是脾胃半表半里的界限。邪气潜伏在此，进入胃腑最速。邪气既然在胃，所以以下法为治疗。这是温热湿浊之邪袭入六经，而传变至阳明胃腑。
这是四季的常疫，即湿温、岚瘴、时气的症状，与毒疠、天行、瘟疫的病自然是两种，截然不同。张景岳所言，是即刻受到温热，邪气已入胃，所以张景岳主张发汗，而吴又可主张泻下。这两者可以从足经（手足三阴三阳经中的足部经脉）处理，同于伤寒论治，分为一路。至于喻嘉言所论述的，是真瘟疫大病，乃天地不正之气，恶毒瘴疠，合病气、口气，交结互蒸。人受到这种气，由口鼻吸入，直行中道，流布三焦，最多出现闭结症状，所以用芳香逐秽、解毒开化的方法。这种毒厉疫邪，与前两种症状各不同，不同于伤寒治法，分逐秽解毒，合行一路，为两大法门。瘟疫大病，别有一种厉毒之气，极易传染，所以往往一家老幼相似，甚至沿门阖境，传染不休。三位医家论述治疗不同，各有其症状，应当随症状审察，合宜而用，不可拘执一说。
长幼传染，众人一般，这是疫气流行，俗名时气。乃是天地秽恶之气，都从口鼻吸入。然而有兼夹六淫的，有不兼夹六淫的。有入足经而为表里证的，有入手经（手太阴肺经等）而忌用汗下法的。应当分途治疗。其辨别关键在于舌象。
邵评：六淫者，风寒暑湿燥火六气之邪，这是四季的常气。大疫发作时，或挟寒，或挟暑，所谓兼夹六淫。总之，纯是疠疫为病，应当分辨邪气从肌表而受，则入足经，可用汗下法；邪由口鼻而受，则入手经，宜宗三焦立法，从心营、肺卫施治，忌用汗下法。
凡是舌苔由白变黄，由黄变黑的，是疫邪由表入里，宜用汗下法。
邵评：邪在表则舌苔白，入里则舌苔黄，入腑热深则舌苔黑。邪在足经，分表里而用汗下之法。
舌苔由白变为鲜红的，是疫邪由卫分及营分，不入足经而入手经，忌用汗下法，宜逐秽解毒，清泄营分。（新法）
邵评：邪在肺卫则舌苔白，入心营则舌红，传入心包，则鲜红起刺。邪在手经，宗心肺卫气，辨明上中下三焦而施治，忌用足经汗下之法。
Nuo is an ancient ritual. The origin of epidemics is very old. Why is Zhang Zhongjing's *Treatise on Cold Damage* (*Shanghan Lun*) not complete? It only mentions warm diseases (*Wenbing*) and heat diseases (*Rebing*), with not a single word mentioning epidemics (*Yi*). Therefore, later generations lacked effective treatment methods. Only in recent times have figures such as Yu Jiayan, Wu Youke, and Zhang Jingyue provided thorough discussions and detailed treatments, uncovering insights previously unexplored by predecessors. However, Zhang Jingyue favored the sweating method (*Hanfa*), Wu Youke favored the purgative method (*Xiafa*), and Yu Jiayan favored using aromatic herbs to expel turbidity (*Fangxiang Zhu Hui*). All three are renowned masters, yet why are their treatment methods so vastly different? It must be understood that all three treatment methods are appropriate, but the types of epidemics they treated were different.
The epidemic discussed by Zhang Jingyue refers to pathogens of the Six Excesses (*Liuyin*: wind, cold, summer-heat, dampness, dryness, fire) and abnormal seasonal qi. Its manifestation is similar to cold damage (*Shanghan*), so he often discusses them together, primarily using the sweating method to fully exploit its efficacy. Zhang Jingyue’s writings are precise and comprehensive.
The epidemic discussed by Wu Youke involves excessive heat qi entering through the mouth and nose, lying latent at the *Moyuan* (the boundary between exterior and interior). Since the pathogen is neither in the exterior nor the interior, it cannot be reached by sweating; thus, there are warnings against forced or harsh sweating. The stomach is close to the *Moyuan*, so pathogens enter the interior rapidly, necessitating urgent and repeated purgation. To understand the transmission of epidemic pathogens, Wu Youke’s discussion is the most detailed. However, the epidemic described by Wu Youke is the common epidemic of the four seasons, commonly known as "seasonal qi syndrome" (*Shiqi Zheng*).
In contrast, the epidemic discussed by Yu Jiayan arises after wars and famines, where disease qi and corpse qi mix with the abnormal qi of heaven and earth, compounded by the intertwining steaming of warm, hot, summer-heat, and dampness during spring and summer. People in this atmospheric intersection have no refuge, leading to continuous transmission throughout communities, becoming a great epidemic. This foul qi enters through the mouth and nose, travels directly through the central pathway, and spreads through the Sanjiao (Triple Burner). It is neither in the exterior nor the interior; sweating fails to resolve it, and purgation leaves it lingering. Therefore, the primary treatment is using aromatic herbs to expel turbidity, combined with detoxification. Thus, the treatments of these three masters each fit their respective indications, and one should not rigidly adhere to one while criticizing another.
For this condition, we also reference these three methods for treatment, divided into two pathways. Sweating and purgation correspond to the exterior-interior treatments of cold damage. The method of expelling turbidity and detoxifying addresses epidemic pathogens latent in the Sanjiao, which are neither in the exterior nor the interior. Listed below, the major principles for treating epidemics are established.
Commentary by Shao: The epidemic symptoms discussed by Zhang Jingyue refer to cold damage occurring in three seasons due to abnormal qi, named "Three-Season Cold Epidemic." Pathogens enter via the skin and muscles, so treatment follows cold damage principles, initially using sweating. If referring to the epidemic symptoms discussed by Wu Youke, these involve damp-warmth, sha, summer-heat, and heat pathogens entering through the mouth and nose, lying latent at the *Moyuan*. The *Moyuan* is the membrane connecting the spleen and stomach, serving as the semi-exterior semi-interior boundary for these organs. Pathogens latent here enter the stomach rapidly. Since the pathogen is in the stomach, purgation is the treatment. This represents warm-heat and damp-turbid pathogens invading the Six Meridians and transmitting to the Yangming Stomach Fu organ.
This is the common epidemic of the four seasons, i.e., damp-warmth, miasma, and seasonal qi syndromes, which are distinctly different from toxic plagues and heavenly行的 epidemics. What Zhang Jingyue describes is immediate exposure to warmth with pathogens already entering the stomach; hence, he advocates sweating, while Wu Youke advocates purgation. These two can be treated via the Foot Meridians, consistent with cold damage theory, forming one pathway. Yu Jiayan’s discussion concerns true severe epidemics caused by abnormal heavenly qi, toxic miasmas, and mixed disease/corpse qi, intertwining and steaming. Humans inhale this qi through the mouth and nose, traveling the central pathway and spreading through the Sanjiao, often causing blockage. Thus, aromatic expulsion of turbidity and detoxification/opening methods are used. This toxic plague pathogen differs from the previous two conditions and does not follow cold damage treatment methods. Expelling turbidity and detoxification form a unified pathway, constituting the second major approach. Severe epidemics possess a unique toxic qi that is highly contagious, often affecting entire families and communities continuously. Although the three masters’ discussions differ, each has specific indications. One must examine symptoms according to the case and apply suitable treatments, avoiding rigid adherence to a single view.
When elders and children are infected similarly, and the masses are affected uniformly, this is the circulation of epidemic qi, commonly called "seasonal qi." It is foul qi from heaven and earth entering through the mouth and nose. Some cases involve concurrent Six Excesses, others do not. Some enter the Foot Meridians presenting as exterior-interior patterns, while some enter the Hand Meridians where sweating and purgation are contraindicated. Treatment must be differentiated. The key to differentiation lies in the tongue.
Commentary by Shao: The Six Excesses are pathogens of wind, cold, summer-heat, dampness, dryness, and fire, which are normal seasonal qis. During major epidemics, these may be accompanied by cold or summer-heat, referred to as "concurrent Six Excesses." In essence, if the disease is purely plague-related, one must distinguish whether the pathogen entered via the skin/muscles (entering Foot Meridians, allowing sweating/purgation) or via the mouth/nose (entering Hand Meridians, requiring Sanjiao-based treatment focusing on Heart Ying and Lung Wei, with sweating/purgation contraindicated).
If the tongue coating changes from white to yellow, and then to black, the epidemic pathogen is moving from exterior to interior; sweating and purgation are indicated.
Commentary by Shao: Exterior pathogens present with white tongue coating; interior pathogens present with yellow coating; deep heat in Fu organs presents with black coating. For pathogens in Foot Meridians, differentiate exterior/interior to apply sweating/purgation.
If the tongue coating changes from white to bright red, the epidemic pathogen is moving from Wei (Defensive) to Ying (Nutritive), entering Hand Meridians rather than Foot Meridians. Sweating and purgation are contraindicated; expelling turbidity, detoxifying, and clearing the Ying level are indicated (New Method).
Commentary by Shao: Pathogens in Lung/Wei present with white coating; entry into Heart Ying presents with red tongue; transmission to Pericardium presents with bright red tongue with prickles. For Hand Meridian pathogens, treat based on Heart/Lung/Wei principles, differentiating Upper/Middle/Lower Sanjiao, and avoid Foot Meridian sweating/purgation methods.