余素不信“龙雷之火补阳则消”之说，后阅叶桂《景岳全书发挥·本草正》，乃知有先
我言
之者矣。其言曰∶今医家每言龙雷之火，得太阳一照，火自消靡。此言甚是悖理。龙雷之起
，正当天令炎热，赤日酷烈之时，未见天寒地冻，阴晦凛冽，而龙雷作者。则知仍因阳亢，
而非热药所能治也。若用热药，乃戴阳、格阳，阴极似阳之症。此处尚要讲究明白。按叶说
甚当。考龙火得水而燔，遇湿而焰之说，本始于王太仆《素问·至真要大论》注，不过借以
形大热之气，不可以寒折之，折之以寒，而热愈不得泄，势必铄尽气血而死。注中所以有物
究方止之喻也。至真要篇前列六气，后列治法，则此注当指感症言。如伤寒在表，身热如灼
，反宜桂枝之热，不宜石膏之寒，故经文此下有反治云云。义止如此，无俟深求。今因叶说
，推原及之叶书，系道光时，其五世孙所刊者。此言在第四卷中。
白粉，说者谓即铅白粉。泉谓经处此方于已服毒药后，是因毒药不效而改治。若铅白粉
，仍
系毒药，何庸以毒继毒乎？盖此方与伤寒少阴猪肤汤方，皆粉蜜同用。成注白粉益气断利，
明是米粉。以彼例此，义可知已。考《外台》治一切药毒方∶甘草三两炙，以水五升，煮取
二升，内粉一合，更煎三两沸，内蜜半两，分服以定止。《千金翼》治药毒不止，解烦闷方
∶甘草二两炙，白梁粉一升，蜜四两，煎服法与《外台》同。泉据此经为说，粉为米粉无疑
。且经云毒药不止者，谓药毒伤其胃气，故蛔动不止。若作毒药杀虫解，则岂甘草粉蜜之甘
和，功反过于毒药，而毒药所不能杀者，杀之以平药乎？必无此理。仲景书文义简奥，有当
即症求方者，有当即方求症者。余作此篇，即方求症也。
我向来不相信“龙雷之火（指下焦相火妄动，似龙雷之象）用补阳药可以消除”的说法。后来阅读叶桂的《景岳全书发挥·本草正》，才知道有人在我之前说过这样的话。他说：现在的医生常说龙雷之火，遇到太阳一照，火自然消亡。这种说法非常违背常理。龙雷之火的兴起，正当天气炎热、烈日酷烈的时候，并没有见到天寒地冻、阴暗凛冽的时候，龙雷之火就发作。由此可知，这仍然是因为阳气亢盛所致，而不是热性药物所能治疗的。如果用药性热的药物，那是针对戴阳证（虚阳上浮）、格阳证（阴盛格阳）等阴极似阳的病证。这里还需要讲究明白。按照叶氏的说法非常恰当。考察“龙火得水而燃烧，遇湿而火焰更旺”的说法，本起源于王太仆（王冰）对《素问·至真要大论》的注解，不过是借以形容大热之气，不可以用寒凉药强行折服，如果用寒凉药折服它，那么热邪更加无法宣泄，势必会烧尽气血而死。注文中所以有“物极则反”的比喻。在《至真要论》篇中前面列出了六气，后面列出了治法，那么这个注解应当是指外感病证而言。比如伤寒在表，身体发热像灼烧一样，反而适宜用桂枝汤的温热性质，不适宜用石膏的寒凉性质，所以经文下面有“反治”之类的说法。义理只到如此，不需要深究。现在因为叶氏的说法，追溯源头到了叶桂的书，这本书是道光年间他的五世孙刊印的。这段话在第四卷中。
白粉，解说的人说是铅白粉。我认为经方将此处放在服用毒药之后，是因为毒药无效而改变治疗方法。如果白粉是铅白粉，仍然属于毒药，何必用毒药接着毒药呢？大概这个方子与《伤寒论》少阴病的猪肤汤方，都是米粉和蜂蜜同用。成无己注释说白粉能益气止利，明明白白是米粉。用那个方子来类比这个方子，义理就可以知道了。考察《外台秘要》治疗各种药物中毒的方子：甘草三两（炙），用水五升，煮取二升，加入粉一合，再煎三沸，加入蜜半两，分次服用以定止毒性。《千金翼方》治疗药物中毒不止，解除烦闷的方子：甘草二两（炙），白梁粉一升，蜜四两，煎服方法与《外台秘要》相同。我根据这些经典作为依据，白粉是米粉毫无疑问。而且经文说“毒药不止者”，是说药毒损伤了胃气，所以蛔虫扰动不止。如果解释为用毒药杀虫解毒，那么难道甘草粉蜜汤的甘缓平和之性，功效反而超过毒药，毒药所不能杀的，用平和的药来杀吗？必定没有这个道理。张仲景的书籍文义简奥，有的应当即症状求方剂，有的应当即方剂求症状。我写这篇文章，就是即方剂求症状的方法。
I have always disbelieved the theory that "Long-Lei Fire (a metaphor for hyperactive ministerial fire in the lower jiao resembling dragon and thunder) can be extinguished by tonifying Yang." Later, upon reading Ye Gui's *Jingyue Quanshu Fahui · Bencao Zheng* (Elucidation of Jingyue's Complete Book · Correct Classification of Materia Medica), I realized that someone had expressed this view before me. He stated: "Current physicians often say that Long-Lei Fire, when exposed to the sun, naturally dissipates. This statement is highly illogical. The rise of Long-Lei Fire occurs precisely during periods of intense heat and scorching sunlight; it does not arise during cold weather, frozen earth, or dark, biting chill. Therefore, we know it is still due to Yang hyperactivity, and cannot be treated with hot herbs. If hot herbs are used, it applies only to conditions like Floating Yang (Dai Yang) or Repelling Yang (Ge Yang), where extreme Yin mimics Yang. This distinction must be clarified. Ye’s explanation is very appropriate. Regarding the saying 'Dragon Fire burns when meeting water and flares when meeting dampness,' this originated from Wang Taipu’s (Wang Bing’s) commentary on the *Suwen · Zhi Zhen Yao Da Lun* (Essential Questions · On the Most Essential Truths). It was merely borrowed to illustrate that excessive heat cannot be forcibly subdued by cold; if subduing it with cold prevents the heat from venting, it will inevitably consume Qi and Blood leading to death. Hence the metaphor of 'things reaching an extreme reverse themselves' in the commentary. In the *Zhi Yao Lun* chapter, Six Qi are listed first, followed by treatment methods; thus, this commentary likely refers to exogenous diseases. For instance, in exterior-stage Shanghan (Cold Damage), where the body feels hot as if burning, one should rather use the warming nature of Guizhi Tang (Cinnamon Twig Decoction) rather than the cooling nature of Shigao (Gypsum Fibrosum). Hence the scripture mentions 'contrary treatment' below. The meaning ends here; there is no need for deep speculation. Now, prompted by Ye’s remarks, I traced the source to Ye’s book, which was published in the Daoguang era by his fifth-generation grandson. This passage appears in Volume Four.
Regarding 'Baifen' (White Powder), commentators claim it is Qian Baifen (Lead White Powder). I argue that the classic formula places this after administering toxic drugs because the previous toxic treatment failed. If Baifen were Lead White Powder, it would still be a toxic substance; why employ toxicity to follow toxicity? Essentially, this formula, along with the Zhufu Tang (Pig Skin Decoction) for Shaoyin disease in Shanghan Lun, both utilize Fenmi (Rice Flour) and Honey. Cheng Wuji’s commentary states that Baifen benefits Qi and stops diarrhea, clearly indicating it is Rice Flour. By analogy, the principle is evident. Examining Waitai Mi Yao (The Outer Cabinet’s Secret Essentials) for treating various drug poisonings: Gancao (Licorice Root) 3 liang (roasted), boiled in 5 sheng of water to yield 2 sheng, then add 1 he of Fen (powder), boil for three more boils, add 0.5 liang of Honey, and divide into doses to stop the toxicity. Qianjin Yi Fang (Supplement to the Thousand Golden Formulas) for persistent drug poisoning and relieving irritability: Gancao (Licorice Root) 2 liang (roasted), Bailiang Fen (White Grain Rice Flour) 1 sheng, Honey 4 liang; the decoction and administration method are identical to Waitai Mi Yao. Based on these classics, it is undoubtedly that the Fen here is Rice Flour. Moreover, the scripture states 'when toxic drugs do not cease,' referring to drug toxicity damaging Stomach Qi, causing continuous ascariasis (roundworm agitation). If interpreted as using toxic drugs to kill parasites and detoxify, would the mild and harmonious nature of Gancao Fenmi Tang (Licorice, Rice Flour, and Honey Decoction) truly surpass toxic drugs, killing what toxic drugs could not with a neutral herb? This is certainly unreasonable. Zhang Zhongjing’s writings are concise and profound; some require deriving formulas from symptoms, while others require deriving symptoms from formulas. In writing this article, I employed the method of deriving symptoms from the formula.