凡非风之多痰者，悉由中虚而然。夫痰即水也，其本在肾，其标在脾。在肾者，以水不
归原，水泛为痰也；在脾者，以食饮不化，土不制水也。不观之强壮之人，任其多饮多食，
则随食随化，未见其为痰也。惟是不能食者，反能生痰，此以脾虚不能化食，而食即为痰也
。故凡病虚劳者，其痰必多，而病至垂危，其痰益甚，正以脾气愈虚，则全不能化，而水液
尽为痰也。然则，痰之与病，病由痰乎？痰由病乎？岂非痰必由于虚乎。可见天下之实痰无几
，而痰之宜伐者亦无几。故治痰者，必当温脾强肾以治痰之本，使根本渐充，则痰将不治而
自去矣。治痰诸法见后及详痰饮本门。
余尝闻之俗传云∶痰在周身，为病莫测。凡瘫痪螈 ，半身不遂等证，皆伏痰留滞而然
。若此痰饮岂非邪类？不去痰邪，病何由愈？余曰∶汝知痰之所自乎？凡经络之痰，盖即津血
之所化也。使果营卫和调，则津自津，血自血，何痰之有？惟是元阳亏损，神机耗败，则水
中无气，而津凝血败，皆化为痰耳。此果痰也，果精血也？岂以精血之外，而别有所谓痰者
耶？若谓痰在经络，非攻不去，则必并精血而尽去之。庶乎可也。否则，安有独攻其痰，而
津血自可无动乎？津血复伤，元气愈竭，随去随化，痰必愈甚。此所以治痰者不能尽，而所
尽者惟元气也。矧复有本无痰气，而妄指为痰以误攻之者，又何其昧之甚也。故凡用治痰之
药，如滚痰丸、清气化痰丸、搜风顺气丸之类，必其元气无伤，偶有壅滞，而或见微痰之不
清者。乃可暂用分消，岂云无效。若病及元气，而但知治标，则未有不日用而日败者矣。
凡是并非中风引起的多痰症状，全部是由于中气虚弱所致。痰其实就是水液代谢失常的产物，其根本在于肾，其标象在于脾。在肾脏方面，是因为水液不能回归本源（肾主水，藏精），导致水液泛滥形成痰饮；在脾脏方面，是因为饮食无法被运化吸收，脾气虚弱不能制约水湿。没有见过身体强壮的人，任凭他们大量饮水进食，食物会随即被消化，并没有见到他们产生痰饮。只有那些不能进食的人，反而容易产生痰饮，这是因为脾虚不能运化食物，食物停滞就变成了痰饮。所以凡是患有虚劳病的人，他们的痰一定很多，而病情发展到垂危阶段时，痰会更加严重，正是因为脾气越来越虚弱，完全不能运化，导致所有的水液都变成了痰饮。那么，痰和疾病之间，是疾病导致了痰呢？还是痰导致了疾病？难道不是痰必然源于虚证吗？由此可见，天下真正的实痰很少，而适合用攻伐法治疗的痰也很少。所以治疗痰饮，必须温补脾阳、强健肾气以治其根本，使身体的根本逐渐充盈，那么痰饮将不用专门治疗而自然消除。关于治疗痰饮的各种方法，详见后文及“痰饮”专章。
我曾经听民间流传的说法说：痰邪遍布全身，致病情况难以预测。凡是瘫痪、抽搐、半身不遂等病症，都是伏痰留滞体内造成的。如果这样的痰饮真的是邪气一类，不去除痰邪，病怎么能痊愈呢？我说：你知道痰产生的来源吗？凡是经络中的痰，其实都是由津液和血液转化而来的。如果营气和卫气调和，那么津液就是津液，血液就是血液，怎么会有痰呢？只有当元阳亏损，神机耗散败坏，导致水中没有阳气蒸腾，津液凝结、血液败坏，才都转化为痰罢了。这究竟是痰呢，还是精血呢？难道在精血之外，还另外有所谓的“痰”这种东西吗？如果说痰在经络中，不通过攻逐就不能去除，那就必须连同精血一起全部去除才行。这样或许还可以。否则，哪有只攻逐痰邪，而津液和血液就能安然不动的道理呢？津液和血液再次受到损伤，元气更加衰竭，痰饮随去随生，反而会更加严重。这就是为什么治疗痰饮的方法不能完全奏效，而真正需要彻底救治的是元气啊。况且还有本来就没有痰气，却错误地指认为痰而妄加攻伐的人，这是多么愚昧啊！所以凡是使用治疗痰饮的药物，比如滚痰丸、清气化痰丸、搜风顺气丸这类方剂，必须是患者元气没有受损，偶尔出现气机壅滞，并且有轻微痰饮不清除的情况，才可以暂时使用分消之法，这难道不是有效的吗？如果疾病已经损伤了元气，却只知道治疗表面症状，那么没有不是每天用药却每天衰败的。
In cases of excessive phlegm not caused by wind-stroke (stroke), it is entirely due to deficiency in the Middle Jiao. Phlegm is essentially water; its root lies in the Kidney, and its branch manifestation lies in the Spleen. Regarding the Kidney aspect, it occurs because water fails to return to its origin, leading to water flooding and transforming into phlegm; regarding the Spleen aspect, it occurs because food and drink are not transformed, and Earth fails to control Water. Observe robust individuals: regardless of how much they drink and eat, food is digested immediately, and one does not see them producing phlegm. Only those who cannot eat tend to produce phlegm, because Spleen deficiency fails to transform food, causing food to stagnate and become phlegm. Therefore, in all cases of consumptive disease (Xu Lao), there must be excessive phlegm, and as the condition approaches critical danger, the phlegm becomes even more severe. This is precisely because Spleen Qi becomes increasingly deficient, completely failing to transform, so that all fluids turn into phlegm. Then, between phlegm and disease, does disease cause phlegm, or does phlegm cause disease? Is it not true that phlegm necessarily stems from deficiency? Thus, it can be seen that true excess-phlegm conditions are few in the world, and very few cases require purgative treatment for phlegm. Therefore, when treating phlegm, one must warm the Spleen and strengthen the Kidney to address the root cause. As the foundation gradually fills, the phlegm will disappear without specific treatment. Various methods for treating phlegm are detailed later and in the dedicated chapter on Phlegm-Fluids.
I have heard folk sayings claiming: "Phlegm circulates throughout the body, making its pathological manifestations unpredictable." Conditions such as paralysis, convulsions, and hemiplegia are all attributed to latent phlegm stagnating within. If such phlegm-fluids are indeed pathogenic factors, how can the disease heal without eliminating the phlegm-pathogen? I replied: Do you know the origin of phlegm? Phlegm in the meridians is actually transformed from Jin-Ye (body fluids) and Xue (blood). If Ying-Qi (Nutritive Qi) and Wei-Qi (Defensive Qi) are harmonious, then Jin-Ye remains Jin-Ye, and Xue remains Xue; where would phlegm come from? It is only when Yuan-Yang (Primordial Yang) is depleted and Shen-Ji (Spiritual Mechanism) is exhausted that there is no Qi in the water, causing Jin-Ye to coagulate and Xue to deteriorate, all transforming into phlegm. Is this truly phlegm, or is it Jing-Xue (Essence and Blood)? Are there really substances called "phlegm" existing apart from Essence and Blood? If one claims that phlegm in the meridians cannot be removed without aggressive purging, then one must purge both Essence and Blood entirely. Only then might it be acceptable. Otherwise, how can one attack only the phlegm while leaving Jin-Ye and Xue undisturbed? If Jin-Ye and Xue are further injured, Yuan-Qi becomes even more exhausted, and phlegm regenerates as fast as it is removed, becoming even more severe. This is why treatments for phlegm often fail, whereas what truly needs complete restoration is Yuan-Qi. Moreover, there are those who mistakenly identify non-phlegm conditions as phlegm and wrongly apply purgatives, which is extremely ignorant. Therefore, when using phlegm-treating formulas such as Gun Tan Wan (Rolling Phlegm Pill), Qing Qi Hua Tan Wan (Clear Qi and Transform Phlegm Pill), or Sou Feng Shun Qi Wan (Search Wind and Smooth Qi Pill), these should only be used temporarily to disperse accumulation if the patient's Yuan-Qi is intact, occasional Qi stagnation exists, and slight phlegm obstruction persists. In such cases, temporary dispersal is effective. However, if the disease has damaged Yuan-Qi, and one only knows how to treat the branch symptoms, the patient will inevitably deteriorate daily despite daily medication.