痘之一症，先贤立论甚详。但近时气候变迁，竟有不同于向日者，莫甚于伏毒，而为时疠壅遏。初起寒热悠悠，腰
腹并无痛楚，两潮而见点，亦色润而形单。并非要害之处，身热未解，得嚏便通。根窠虽立，不易掀发。一到三朝，神
蒙气喘，斑点全无，唇不肿而口不渴，火伏内攻，迅如反掌，痘未退缩，即已喘闭告竭。虽多识者，进以芳香双解，大
剂劫夺，一无奏绩，亦未如之何也已矣。
《内经·气交变大论》详言岁运，《六元正纪大论》详言司天在泉，而今似有不验者，何欤？盖岁运已分太少，而一
岁之中，再分为五运，五运之中，又分主客，主客之中，又分太少司天在泉，再与间气分而为六，六气之中，又分主客，
是每候中必有岁运与司天、在泉，及主运、客运、主气、客气六者矣。角、征、宫、商、羽，与风、火、湿、燥、寒，
杂合于一时，变化靡穷。无怪执岁运之说者，司天在泉不验，执司天在泉之说者，岁运不验，执五运六气之说者，岁运
与司天在泉皆不验，几疑古圣贤书为不可尽信矣。不知五运六气，《经》文虽逐一分言，而未及合参之理；然《天元纪》、
《六微旨》二篇，论至天符岁会，则参合而言。如天符乃岁运，与司天相会，奉天行令而主半年，譬之相辅也，故曰执
法也。故中其病者，危而速也。岁会乃岁运与年辰相会，犹为平气，而主一年，譬之方伯也，故曰行令也。故中其病者，
徐而持也。至于太乙天符，则司天、岁运、年辰三者会合，偏盛极焉。故中其病者，暴而死也。吾侪在医喻医，如一方
中纯寒纯热，其性自偏，服之未有不验者。其非天符、岁会之年，五行错杂，犹之一方中苦辛相制，寒热杂陈，则气味
皆轻，自不觉其利害耳。天符、岁会如此，可知五运六气亦须参合以类推矣。《内经》未言及此者，提其纲而略其目也。
然余更有说者，《经》言中执法者，其病速而危；中行令者，其病徐而持；中贵人者，其病暴而死。曰中、曰其，乃指偏
胜之时，即中此偏胜之邪，于是其病如斯，非泛言其年得病，无论风、寒、暑、湿、燥、火，一概如此断也。况偏胜之
时，虽必有其邪，亦非举世之人而尽中之也。或起居不慎，或寒暖失宜，凡属外感皆然。再壮者气行则散，怯者着而为
病，则是中其邪者，本非常有，何谓《经》文之不验耶？愚意以为运气之说如此。抑更有释天符太乙之说者，谓非一年
之病皆然，当以得病之一日为言，如戊子日亦称天符，戊午日即为太乙，似乎近理，而与中、其二字，究隔一层，仍当
作值其日而中其邪，或合以其年其日而中其邪，如此推之，窃谓断无不验者。
The disease of smallpox has been discussed in detail by ancient sages. However, due to recent changes in climate, there are cases that differ significantly from the past, most notably those involving latent toxins (latent pathogenic factors) obstructed by epidemic pestilence (epidemic pathogenic qi). At the onset, there is alternating chills and fever without pain in the waist or abdomen. After two cycles (or tidal phases), spots appear; they are moist in color and sparse in form. They do not occur in critical areas. The body heat remains unresolved, but clears up after sneezing. Although the base of the pustule forms, it is difficult to raise and erupt. By the third day, the patient suffers from mental confusion and asthma (wheezing with shortness of breath), while the macules and papules completely disappear. The lips are not swollen, and there is no thirst. This indicates fire toxin (heat pathogen) lurking internally and attacking inwardly, changing as swiftly as flipping a hand. Before the smallpox lesions can recede, the patient already presents with asthmatic closure (severe wheezing and airway obstruction) and exhaustion of vital energy. Even experienced physicians, using aromatic dual-resolving methods (aromatic herbs to open orifices and resolve exterior-interior pathogens) or large doses of drastic purgatives, achieve no effect and are helpless.
The *Neijing* (Classic of Internal Medicine) · Chapter on Changes in the Interaction of Qi (*Qi Jiao Bian Da Lun*) details the Annual Motion (Sui Yun), and the Chapter on the Correct Principles of the Six Origins (*Liu Yuan Zheng Ji Da Lun*) details the Sovereign Heaven (Si Tian) and Nether Heaven (Zai Quan). Yet now, these theories seem inapplicable in some respects. Why? It is because the Annual Motion is divided into Taiyi (Great Yang/Excess) and Shaoyin (Lesser Yin/Deficiency). Within a year, it is further divided into Five Motions (Wu Yun); within the Five Motions, there are Host Motion (Zhu Yun) and Guest Motion (Ke Yun); within Host and Guest motions, there are distinctions based on Taiyi/Shaoyin for Sovereign Heaven and Nether Heaven, which are then combined with Intercalary Qi (Jian Qi) to form the Six Qi (Liu Qi). Within the Six Qi, there are again Host Qi and Guest Qi. Thus, each period (Hou) necessarily contains six factors: Annual Motion, Sovereign Heaven, Nether Heaven, Host Motion, Guest Motion, Host Qi, and Guest Qi. The five tones (Jue, Zhi, Gong, Shang, Yu) and the five elements (Wind, Fire, Dampness, Dryness, Cold) mix together at any given time, resulting in endless variations. No wonder those who adhere strictly to the theory of Annual Motion find Sovereign Heaven and Nether Heaven inapplicable; those adhering strictly to Sovereign Heaven and Nether Heaven find Annual Motion inapplicable; and those adhering to the comprehensive theory of Five Motions and Six Qi find both Annual Motion and Sovereign Heaven/Nether Heaven inapplicable. This leads one to suspect that the books of ancient sages cannot be entirely trusted. However, although the *Neijing* discusses Five Motions and Six Qi separately, it does not explicitly state the principle of comprehensive reference. In the chapters *Tian Yuan Ji Da Lun* and *Liu Wei Zhi Da Lun*, when discussing "Tian Fu" (Heavenly符/Synergy) and "Sui Hui" (Annual Meeting), they are discussed in conjunction. For instance, "Tian Fu" occurs when the Annual Motion meets with Sovereign Heaven, executing the Heavenly mandate for half a year, akin to an assisting minister; thus it is called "Executing Law" (Zhi Fa). Therefore, those affected by this pattern suffer from critical and rapid illness. "Sui Hui" occurs when the Annual Motion meets with the Earthly Branch of the year, representing a Balanced Qi (Ping Qi) governing the whole year, akin to a regional governor; thus it is called "Executing Order" (Xing Ling). Therefore, those affected suffer from slow and persistent illness. "Tai Yi Tian Fu" occurs when Sovereign Heaven, Annual Motion, and the Earthly Branch converge, leading to extreme excess. Therefore, those affected suffer from sudden and fatal illness. We doctors should understand this medically: just as a prescription containing purely cold or purely hot herbs has a biased nature and will inevitably show effects, so too do these energetic patterns. In years that are not Tian Fu or Sui Hui, the Five Elements are mixed, similar to a prescription where bitter and acrid flavors counteract each other, and cold and hot properties are intermingled; the medicinal qualities become mild, and their harmful or beneficial effects are not readily perceived. Since this applies to Tian Fu and Sui Hui, it follows that Five Motions and Six Qi must also be comprehensively referenced for deduction. The *Neijing* omitted this detail by providing the outline while omitting the specifics. Furthermore, I have another explanation: The *Neijing* states that meeting "Executing Law" results in rapid and critical illness; meeting "Executing Order" results in slow and persistent illness; meeting "Noble Person" (Gui Ren) results in sudden death. The characters "Zhong" (to strike/meet) and "Qi" (its/her) refer to the time of excessive dominance, meaning contracting this dominant pathogen causes such illness. It does not mean that everyone getting sick in that year, regardless of whether the pathogen is Wind, Cold, Summer-heat, Dampness, Dryness, or Fire, will follow this rule uniformly. Moreover, during times of dominance, although the pathogen exists, it does not affect everyone. Whether due to careless living habits or improper temperature regulation, all external contractions are subject to individual constitution. Those with strong Qi disperse the pathogen through circulation; those with weak Qi retain it and fall ill. Thus, contracting such specific pathogenic influences is not common. Why claim the *Neijing* is inapplicable? My view is that the theory of Luck (Yun Qi) should be understood this way. Additionally, some interpret "Tian Fu" and "Tai Yi" not as applying to the whole year's illnesses, but specifically to the day of onset—for example, Wu Zi days are called Tian Fu, and Wu Wu days are Tai Yi. While this seems reasonable, it still differs slightly from the nuance of "Zhong" and "Qi." It is better interpreted as encountering the specific day and contracting the corresponding pathogen, or combining the year and day's energies to contract the pathogen. By deducing in this manner, I believe there will be no instances of inapplicability.