晚发。缓发也。与即病相对待。又与触发相对待。专邪自发。不感外气。本是伤寒中之正病。成注谓后来之疾
也。语意不明。他家更以伤寒杂证释之。殊不知此乃下焦伏寒。日久化湿。留连淫溢。以渐上行。故病之来势甚缓。
停蓄于中。至六七日。结为水气。与即病恶寒发热之表证不同。又不似触发者之暴急也。自脉阴阳俱紧。口中气出。
唇口干燥。蜷卧足冷。以下。皆晚发见证。不知者分作两截。专以若脉迟至六七日不欲食。属之。晚发。是泥于此
为晚发之句。不知此乃从六七日后。追思而通括之。只作一读连下成句。晚发二字。是现成语气犹言此因晚发。以
致水停故也。六七日句。与上文七日以来句。八日以上句平列。皆晚发转证。(一寒盛而阳气争之。一寒湿两盛。
阳气不能自持。一寒去而湿存也。)只因此为晚发句倒装于此。遂致眩惑。若提在勿妄治也前。便自晓然。大抵此
病。寒邪久伏。菀为夹湿。湿性濡滞。故其势甚缓其脉甚迟。其证寒多热少。神昏肢 。迁延日久。有误作虚证。
而用补者。予曾延医。见读医随笔。寒湿下受。直伤少阴。变证多端。搜治匪易。篇中又有汗病篇。亦晚发之病也。
当参观之。兹不赘录。夫前言脉阴阳俱紧者。寒盛也。此言脉迟者。寒势稍衰而湿盛也。
按晚发。只训缓发寒中夹湿。以病势之缓立名。非以发时之迟取义。冬月伏寒。发于春夏。固为晚发。上月伏
寒。发于下月。亦为晚发。事所常有。不必怪说。不但本章是晚发。即前自脉浮而迟。后至病六七日。手足三部。
脉皆至章。亦皆是晚发之类。清邪中上浊邪中下章。是邪入血分。荣卫不通。初起似可麻黄升麻汤主之。本章是邪
在气分。上热下寒。三转证中。以吐利为最危。脉浮而迟章。是湿搏于表。中气不足。口噤躁扰章。是湿结膻中。
热搏于里。即汗病篇所说是也。
Late onset. It refers to slow onset. It stands in contrast to "immediate illness" (illness occurring immediately after pathogen invasion). It also stands in contrast to "triggered onset" (sudden onset due to a trigger). This is the spontaneous manifestation of the pathogen, without contracting new external pathogens. It is originally the proper disease within *Shanghan* (Cold Damage). Cheng Wuji's commentary describes it as "diseases appearing later," which is ambiguous. Other physicians further interpret it using miscellaneous *Shanghan* syndromes. They fail to realize that this is latent cold in the Lower Jiao (Lower Burner), which over time transforms into dampness. The dampness lingers and overflows, gradually moving upward. Therefore, the onset of the disease is very slow. It stagnates and accumulates in the Middle Jiao (Middle Burner). By the sixth or seventh day, it coagulates into water qi. This differs from the exterior syndrome of aversion to cold and fever seen in immediate illness, and it is not as sudden and urgent as triggered onset. From the pulse being tight at both Yin and Yang positions, breath issuing from the mouth, dry lips and mouth, curling up while lying down, and cold feet onwards, these are all manifestations of late onset. Those who do not understand divide it into two parts, specifically attributing the sentence "if the pulse is slow, reaching the sixth or seventh day with loss of appetite" to late onset. "Late onset" stems from clinging to the phrase "this is due to late onset." They fail to realize that this is a retrospective generalization made after the sixth or seventh day. It should simply be read as one continuous sentence connected to the following text. The term "late onset" is a set phrase, meaning "because of the late onset, water retention has occurred." The "sixth or seventh day" clause is parallel to the earlier "since the seventh day" clause and the "above eight days" clause; all are transforming syndromes of late onset. (One case involves severe cold struggling against Yang Qi; another involves simultaneous excess of cold and dampness where Yang Qi cannot sustain itself; the third involves the departure of cold leaving dampness behind.) It is only because the clause "this is due to late onset" is inverted here that confusion arises. If placed before "do not treat rashly," it would be clear. Generally, in this disease, cold pathogens have been latent for a long time, becoming constrained and mixed with dampness. Dampness is sticky and obstructive; thus, the progression is very slow, the pulse is very slow, the syndrome features more cold than heat, mental confusion, and cold limbs. After lingering for a long time, some mistakenly treat it as a deficiency syndrome and use tonification. I once consulted a physician and saw in *Reading Medical Notes* that cold-dampness entering from below directly injures Shaoyin (Lesser Yin), leading to numerous transforming syndromes, making treatment difficult. That chapter also includes a section on sweating disorders, which is also a type of late onset. Readers should consult it. I will not elaborate further here. The earlier mention of pulses tight at both Yin and Yang indicates severe cold. The current mention of a slow pulse indicates that the cold pathogen has slightly weakened while dampness has become prominent.
Note: "Late onset" is defined solely as slow onset, where cold is mixed with dampness, named based on the slowness of the disease progression, not based on the lateness of the time of onset. Cold latent in winter manifesting in spring or summer is indeed late onset. Cold latent in one month manifesting in the next month is also late onset. This is common and need not be strange. Not only is this chapter about late onset, but the previous chapter from "pulse floating and slow" to "by the sixth or seventh day of illness, pulses in the hand and foot three positions are present" are also types of late onset. The chapter "Clear pathogens attack above, turbid pathogens attack below" describes pathogens entering the Blood level, causing obstruction of Ying (Nutrient) and Wei (Defensive) circulation; initially, Mahuang Shengma Decoction might be considered. This chapter describes pathogens in the Qi level, with upper heat and lower cold; among the three transforming syndromes, vomiting and diarrhea are the most critical. The "pulse floating and slow" chapter describes dampness contending at the exterior with insufficient Middle Qi. The "jaw stiffness and restlessness" chapter describes dampness congealing in the Danzhong (Chest Center) with heat contending in the interior, which corresponds to what is described in the sweating disorder section.