经云∶春伤于风，夏生飧泄，邪气留连，乃为洞泄。盖因风木之邪，留连既久，木气克土，则仓廪不藏
而为洞泄，可见是病，亦由伏气所致也。李士材曰∶洞泄一名濡泄，濡泄因于湿胜。此病非但因伏气内留，中
气失治，亦有湿气相兼致病也。考其脉象，软缓乏力，或关脉兼弦，身重神疲，肢体懈怠，下利
清谷，小便短赤是也，宜乎培中泻木法加苍术、泽泻治之。经曰∶肾脉小甚为洞泄。盖肾为胃关，因肾虚失
闭藏之职，伏邪乘虚而深陷也，宜乎补火生土法加煨葛、荷叶治之。总之脾虚以补中为先，肾虚以固下为
亟，风胜佐之疏透，湿胜佐之渗利，临证之顷，神而明之，则旋踵之祸，庶几免焉。
程曦曰∶观飧泄洞泄之论，总不离乎木气克土，故治洞泄，皆仿飧泄之法，然其中之虚实，当细别之。
盖飧泄因脾虚为多，所以完谷不化；洞泄因湿胜为多，所以体重溺红。属脾
虚者，不宜偏利；属湿胜者，不宜偏补。斯二者，皆当审其虚实而分治之。
寒泻者，因寒而致泻也，不比飧泄洞泄，皆属春伤于风之伏气。伏气之泻，前二篇已详晰矣，所有寒、
火、暑、湿、痰、食等泻，虽不因乎伏气，然又不可不详。盖寒泻致病之原，良由
感受乎寒，寒气内袭于脾，脾胃受寒则阳虚，虚则不司运用，清
阳之气，不主上升，反下陷而为便泻。故所下澄沏清冷，俨如鸭粪，腹中绵痛，小便清白，脉来缓怠近迟，
此宜暖培卑监法去西潞、益智，加木香、楂炭治之。书又云∶寒泻即 泻，以其泻
出如鸭 之粪也。又谓∶鸭溏者，湿兼寒也。若有湿证所着，宜佐化湿之药，随其证而加减可也。
《黄帝内经》说：春季感受风邪，到了夏季就会发生完谷不化的飧泄；如果邪气在体内滞留日久，就会演变为洞泄。这是因为风木之邪长期滞留，导致木气克制脾土，使得脾胃（仓廪）无法固藏食物，从而形成洞泄。由此可见，这种病也是由伏气（潜伏体内的邪气）所致。李士材说：洞泄又名为濡泄，濡泄是由于湿气过胜引起的。此病不仅因为伏气内留、中气失调，也有湿气夹杂致病的情况。考察其脉象，表现为脉软缓乏力，或者关脉兼见弦象，身体沉重、精神疲乏，肢体懈怠无力，大便下利清稀且含有未消化的食物，小便短少色赤，适宜采用培中泻木法，并加入苍术、泽泻进行治疗。《内经》说：肾脉细小甚者为洞泄。这是因为肾为胃之关窍，因肾虚失去了闭藏的功能，伏邪乘虚深入，所以适宜采用补火生土法，并加入煨葛根、荷叶进行治疗。总之，脾虚以补益中气为先务，肾虚以固摄下元为急迫，风邪偏胜则辅以疏透之法，湿邪偏胜则辅以渗利之法，临证时若能灵活变通、明察秋毫，那么顷刻间发生的祸患，或许就能避免。
程曦说：观察飧泄和洞泄的论述，总离不开木气克制脾土这一机理，因此治疗洞泄，都仿照治疗飧泄的方法，然而其中的虚实性质，应当仔细辨别。大概飧泄多因脾虚引起，所以大便中含有未消化的食物；洞泄多因湿胜引起，所以身体沉重、小便红赤。属于脾虚的，不宜过度使用利水渗湿药；属于湿胜的，不宜过度使用滋补药。这两种情况，都应当审察其虚实而分别治疗。
寒泻，是因为感受寒邪而导致的腹泻，不同于飧泄和洞泄那样都属于春季伤于风的伏气所致。关于伏气引起的腹泻，前两篇已经详细阐述过了。至于寒、火、暑、湿、痰、食等引起的腹泻，虽然不一定由伏气引起，但也不可不详细论述。寒泻致病的根本原因，确实是由于感受了寒邪，寒气内侵脾脏，脾胃受寒则阳气虚弱，阳气虚弱则不能主持运化功能，清阳之气不能正常上升，反而下陷导致便泻。因此排出的粪便清澈冷凉，宛如鸭粪，腹部绵绵作痛，小便清白，脉象缓怠接近迟脉，这适宜采用暖培卑监法，去掉西潞党参、益智仁，加入木香、山楂炭进行治疗。医书又说：寒泻即溏泄，因为其泻出物像鸭粪一样。又说：鸭溏，是指湿气兼夹寒邪。如果有湿证的征象，适宜辅助使用化湿的药物，根据具体证候进行加减即可。
The *Classic of Difficult Issues* (Nanjing) states: "Injury by wind in spring leads to undigested stool diarrhea (Sun Xie, diarrhea with undigested food) in summer; if the pathogenic factor lingers, it becomes hole diarrhea (Dong Xie, severe watery diarrhea)." This is because the wind-wood pathogen lingers for a long time, causing wood qi to overact on earth qi (spleen/stomach), resulting in the failure of the granary (stomach and spleen) to store, thus leading to Dong Xie. It can be seen that this disease is also caused by latent pathogenic factors (Fu Qi). Li Shicai stated: "Dong Xie is also known as Ru Xie (damp diarrhea); Ru Xie is caused by excessive dampness." This disease is not only due to internal retention of latent pathogens and dysfunction of middle qi, but also involves concurrent pathogenic dampness. Examining its pulse presentation, it is soft, slow, and weak, or the guan position shows a wiry quality; symptoms include heavy body, mental fatigue, limb laxity, passage of clear undigested stool, and short, dark urine. The appropriate treatment is Pei Zhong Xie Mu Fa (Nourish Middle and Drain Wood method) added with Cang Zhu (Atractylodis Rhizoma) and Ze Xie (Alismatis Rhizoma). The *Classic* states: "If the kidney pulse is very small, it indicates Dong Xie." This is because the kidney serves as the gate of the stomach; due to kidney deficiency failing in its function of closure and storage, latent pathogens sink deeply into the deficiency. The appropriate treatment is Bu Huo Sheng Tu Fa (Tonify Fire to Generate Earth method) added with Wei Ge Gen (Prepared Puerariae Radix) and He Ye (Nelumbinis Folium). In summary, for spleen deficiency, tonifying the middle is paramount; for kidney deficiency, securing the lower is urgent. If wind is excessive, assist with dispersing and penetrating methods; if dampness is excessive, assist with leaching and draining methods. During clinical practice, if one can apply these principles with spiritual clarity and adaptability, the disaster that could occur at any moment may hopefully be avoided.
Cheng Xi stated: "Observing the discussions on Sun Xie and Dong Xie, they all revolve around wood qi overacting on earth. Therefore, treating Dong Xie generally follows the methods for Sun Xie; however, the excess and deficiency within must be carefully distinguished." Generally, Sun Xie is mostly due to spleen deficiency, hence the presence of undigested food; Dong Xie is mostly due to excessive dampness, hence the heavy body and red urine. For cases belonging to spleen deficiency, one should not rely excessively on draining; for cases belonging to excessive dampness, one should not rely excessively on tonifying. Both conditions require assessing excess and deficiency to treat them separately.
Han Xie (Cold Diarrhea) is diarrhea caused by cold, which differs from Sun Xie and Dong Xie, as those belong to latent pathogens from spring wind injury. Diarrhea caused by latent pathogens has been detailed in the previous two chapters. Although diarrhea caused by cold, fire, summerheat, dampness, phlegm, and food stagnation does not necessarily stem from latent pathogens, it cannot fail to be discussed in detail. The root cause of Han Xie is indeed contracting cold; cold qi invades internally affecting the spleen. When the spleen and stomach are affected by cold, yang qi becomes deficient. Due to deficiency, it fails to govern transformation and transportation. Clear yang qi fails to ascend properly and instead sinks downward, causing loose stools. Therefore, the excrement is clear, cold, and resembles duck feces; there is continuous abdominal pain; urination is clear and white; and the pulse is slow, lethargic, and approaching a delayed rate. The appropriate treatment is Nuan Pei Bei Jian Fa (Warm and Nourish the Inferior Monitor method), removing Xi Lu Dang Shen (Codonopsis Pilosula) and Yi Zhi Ren (Alpiniae Oxyphyllae Fructus), and adding Mu Xiang (Aucklandiae Radix) and Zha Tan (Charred Crataegi Fructus). Medical texts also state: "Han Xie is equivalent to Tang Xie (pasty diarrhea), because the discharge resembles duck feces." It is also said: "Ya Tang (duck paste diarrhea) refers to dampness combined with cold." If signs of dampness are present, it is appropriate to add herbs that transform dampness, adjusting according to the specific syndrome.