大法，秋宜下。
秋时阳气下行，则邪亦在下，故宜下。
凡服下药，（赵本作“凡可下者”）用汤胜丸，（赵本有“散”字）中病即（赵本作“便”）止，
不必尽剂也。
汤之为言荡也，涤荡肠胃，溉灌脏腑，推陈燥结，却热下寒，破散邪疫，理导润泽枯槁，悦人皮肤，益
人血气。水能净万物，故胜丸散。中病即止者，如承气汤证云∶若一服，利而（医统本作“则”）止后服。
又曰∶若一服，谵语止，更莫复服。是不尽剂也。
下利，三部脉皆平，按之心下硬者，急下之，宜大承气汤。
下利者，脉当微厥，今反和者，此为内实也。下利三部脉平者，已为实，而又按之心下硬者，则知
邪甚也，故宜大承气汤下之。
下利，脉迟而滑者，内实也。利未欲止，当下之，宜大承气汤。
经曰∶脉迟者，食干物得之。《金匮要略》曰∶滑则谷气实。下利脉迟而滑者，胃有宿食也。脾胃伤食，不
消水谷，是致下利者，为内实，若但以温中浓肠之药，利必不（医统本作“未”）止，可与大承气汤，
下去宿食，利自止矣。
问曰∶人病有宿食，何以别之？师曰∶寸口脉浮而大，按之反涩，尺中亦微而涩，故知有宿食，当下之，
宜大承气汤。
寸以候外，尺以候内；浮以候表，沉以候里。寸口脉浮大
者，气实血虚也；按之反涩，尺中亦微而涩者，胃有宿食里气不和也。与大承气汤，以下宿食。
下利，不欲食者，以有宿食故也，当宜（赵本无“宜”字）下之，与（赵本作“宜”）大承气汤。
伤食则恶食，故不欲食，如伤风恶风、伤寒恶寒之类也。
下利瘥后，（赵本无“后”字）至其年月日（赵本有“时”字）复发者；以病不尽故也，当下之，宜大承气汤。
乘春，则肝先受之；乘夏，则心先受之；乘至阴，则脾先受之；乘秋，则肺先受之。假令春时受病，气
必伤肝，治之难（医统本作“虽”）愈，邪有不尽者，至春时元受月日，内外相感，邪必复动
而痛（医统本作“病”）也。下利为肠胃疾，宿积不尽，故当下去之。
下利，脉反滑，当有所去，下之（赵本无“之”字）乃愈，宜大承气汤。
《脉经》曰∶滑脉者，为病（熊校记∶脉滑者为宿食也。汪本宿误病）食也。下利脉滑，则内有宿食，
故云当有所去，与大承气汤，以下宿食。
病腹中满痛者，此为实也，当下之，宜大承气（赵本有“大柴胡”三字）汤。
《金匮要略》曰∶病者腹满，按之不痛为虚，痛为实，可下之。腹中满痛者，里气壅实也，故可下之。
伤寒后，脉沉沉者，内实也，下解之，（赵本作“之解”）宜大柴胡汤。
伤寒后，为表已解，脉沉为里未和，与大柴胡汤，以下内实。经曰∶伤寒瘥以后更发热，脉沉实者，以下解之。
脉双弦而迟者，必心下硬；脉大而紧者，阳中有阴也，可以（赵本无“以”字）下之，宜大承气汤。
《金匮要略》曰∶脉双弦者寒也。经曰∶迟为在脏。脉双弦而迟者，阴中伏阳也，必心下硬。大则为阳，
紧则为寒，脉大而紧者，阳中伏阴也，与大承气汤以分阴阳。
General principles indicate that purgation is suitable in autumn.
In autumn, yang qi descends, and pathogens also reside in the lower part; therefore, purgation is appropriate.
For those taking purgatives, (Zhao's edition reads "those who can be purged") decoctions are superior to pills, (Zhao's edition includes the character for "powder") treatment should cease once the disease is addressed, (Zhao's edition reads "then") without necessarily completing the full dosage.
The term "decoction" implies sweeping away; it cleanses the intestines and stomach, irrigates the viscera, pushes out old dry accumulations, eliminates heat and expels cold, breaks up and disperses pathogenic epidemics, regulates and guides to moisten withered states, benefits the skin, and nourishes blood and qi. Water can purify all things, thus decoctions surpass pills and powders. Ceasing treatment upon addressing the disease is exemplified by the Chengqi Tang syndrome: "If after one dose, bowel movement occurs, stop subsequent doses." It also states: "If after one dose, delirium ceases, do not take more." This illustrates not completing the full dosage.
In cases of diarrhea where pulses at the three positions are all level, but pressure on the epigastrium reveals hardness, urgent purgation is required, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
Diarrhea typically presents with a faint or knotted pulse; if the pulse is instead harmonious/level, this indicates internal excess. Diarrhea accompanied by level pulses at the three positions already suggests excess; combined with hardness upon pressing the epigastrium, it confirms severe pathogenic factors, warranting purgation with Da Chengqi Tang (Major Order the Qi Decoction).
In cases of diarrhea with a slow and slippery pulse, there is internal excess. Since the diarrhea has not ceased, purgation is indicated, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
Classics state: A slow pulse results from consuming dry foods. *Jingui Yaolue* states: A slippery pulse indicates substantial grain qi. Diarrhea with a slow and slippery pulse indicates retained food in the stomach. Spleen and stomach injury from food stagnation leads to an inability to digest water and grains, causing diarrhea; this constitutes internal excess. If only warming and astringent intestinal medicines are used, the diarrhea will likely not cease. Da Chengqi Tang (Major Order the Qi Decoction) may be administered to remove the retained food, after which the diarrhea will naturally stop.
Question: How can retained food be distinguished in patients? The Master said: The cunkou pulse is floating and large; upon pressure, it feels choppy, and the chi position is also slightly choppy. Thus, retained food is known to exist, requiring purgation, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
The cun position inspects the exterior; the chi position inspects the interior. Floating pulses inspect the exterior; deep pulses inspect the interior. A floating and large cunkou pulse indicates excess qi and deficient blood. Choppy upon pressure and slightly choppy at the chi position indicates retained food in the stomach and disharmony of interior qi. Da Chengqi Tang (Major Order the Qi Decoction) is given to purge the retained food.
In cases of diarrhea with loss of appetite, it is due to retained food; purgation is indicated, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
Food injury causes aversion to food, hence the lack of appetite, similar to wind injury causing aversion to wind or cold injury causing aversion to cold.
If diarrhea recurs on the same month, day, or year after recovery, it is because the pathogen was not fully eliminated; purgation is indicated, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
If contracted in spring, the liver is affected first; in summer, the heart; during the late summer transition, the spleen; in autumn, the lung. For instance, if illness occurs in spring, qi inevitably injures the liver, making treatment difficult to cure. If pathogens remain unresolved, when the time arrives corresponding to the original onset in spring, internal and external resonance causes the pathogen to reactivate, leading to pain. Diarrhea is a gastrointestinal disorder; since retained accumulation is incomplete, it must be purged.
In cases of diarrhea with a surprisingly slippery pulse, something needs to be expelled; purgation leads to recovery, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
*Mai Jing* states: A slippery pulse indicates disease caused by retained food. (Xiong's correction notes: Slippery pulse indicates retained food. Wang's edition mistakenly writes 'disease' for 'retained'). Diarrhea with a slippery pulse indicates internal retained food; thus, it is said that something must be expelled. Da Chengqi Tang (Major Order the Qi Decoction) is given to purge the retained food.
Abdominal fullness and pain indicate excess; purgation is required, preferably using Da Chengqi Tang (Major Order the Qi Decoction) (Zhao's edition adds "Da Chaihu").
*Jingui Yaolue* states: Abdominal fullness that is non-tender upon pressure is deficiency; tender/fullness is excess, allowing for purgation. Abdominal fullness and pain indicate interior qi congestion and excess, permitting purgation.
After Shanghan, a deep pulse indicates internal excess; resolution via purgation is needed, preferably using Da Chaihu Tang (Minor Order the Qi Decoction).
Post-Shanghan, with the exterior resolved, a deep pulse indicates unharmonized interior. Da Chaihu Tang (Minor Order the Qi Decoction) is given to purge internal excess. Classics state: After Shanghan recovery, if fever recurs with a deep and solid pulse, purgation resolves it.
A double-string-like and slow pulse indicates epigastric hardness; a large and tight pulse indicates yin within yang, allowing for purgation, preferably using Da Chengqi Tang (Major Order the Qi Decoction).
*Jingui Yaolue* states: Double-string-like pulses indicate cold. Classics state: Slow pulses indicate zang organ involvement. A double-string-like and slow pulse indicates hidden yang within yin, resulting in epigastric hardness. Large pulses belong to yang; tight pulses belong to cold. A large and tight pulse indicates hidden yin within yang. Da Chengqi Tang (Major Order the Qi Decoction) is given to differentiate and harmonize yin and yang.