脾位三阴。为六经之内主。以地德而上承乎天。故广明之下。即为太阴太阴掌太仓之出入。为心君储精待用之府。
所以散精微赡运用。为胃行精液者也。其职主运。故以升为德。其部当水谷之海。故以湿为苦。若有余不足。而为病淫
与郁。则水火二气皆能病之。水病则壅。壅则伤气。虚而不运。腹满胀。胃脘痛。肠鸣飧泄。食不化。身体皆重。上为
大寒。火病则不濡。不濡则伤血。血枯而燥。胃气乃浓。善饥肉痿。足不收行。善螈。脚下痛。舌本强。食则呕。食不
下。烦心。水闭黄胆脾约。必也常使少阳和气常动于其中。则土润而升。不伤于燥。土健而运。不伤于湿。斯为得其平
矣。然其居中央孤脏。以灌四旁。而主四末。病则必沦于四脏。而四脏有病。亦必待养于脾。若脾绝、则四脏即无以为
生。是后天之本绝。较捷于先天之根绝也。故治四脏者。不可以不养脾。调停脾胃。医中之王道也。其曰腹满 胀。支
膈胁。下厥上冒。以为过在太阴阳明者。太阴土壅。则本经不运。而阳明之气不腾。是以不能出营卫以升达于上下。
不达于下。则肾气独沉。故下厥。不升于上。则肺气不行。故上冒。此为中气不足。中州之病。是以甚则入脾也。
肾在人身为阴中之少阴。应天时而主冬令。故太阳寒水司气。不归膀胱而归肾。盖以肾之为气。主蛰伏。主归藏。
天地敛藏之气。必归于此。是以寒水唯肾得主之也。顾其脏位为先天根柢。与心火为对待。故又为阴中之太阴。而先天
真火亦涵于此。是虽各以为体。寒为位。而实以火为用也。易象坎。画一阳入二阴之间。为体阳而用阴。其性流行。又
体阴而用阳。人身之肾。其坚滑者水之体。其流动者火之用。得水火两具。而藏命门真火于至阴之中。坎之象也。夫阳
气生于阴中。静极而动。能升阴精以上奉离宅。所谓升坎填离之妙。乃先天之大本大源也。以其火藏水中。水升天上。
故常以水为海。火为龙。水暖而龙潜。水寒而龙起。是以肾家之病。不止水衰为土所克。而又有水火两病也。如湿淫寒
淫所胜。则 肿、骨痛、阴痹、头项痛、时眩、饥不欲食。寒气自伤。则清厥。意不乐。腹大胫肿。喘嗽身重。寝汗出。
龙火为患。则面如漆紫。咳吐则有血。喝喝而喘。心如悬。口热咽干。烦心之类。皆肾家寒湿之淫。与水空火腾之为患
也。至于水藏土中。而所以为蛰藏者。实藉土封之力。经云、肾合精其主脾。是封藏必在脾气。故不曰克而曰生。此前
人补肾。用六味入茯苓山药之妙理也。先哲之言曰。肾家水不足。勿熄其火。须滋阴之源以配火。肾家火不足。勿伤其
水。须益火之主以配水。有旨哉。
脾位于三阴经之中，是六经的内部主宰。它像大地承载万物一样向上承接天阳之气。因此，在“广明”（指阳气充盛的状态）之下，就是太阴脾土。太阴脾掌管胃腑的纳食与排泄，是为心君储存精气以备使用的脏腑。
所以，脾的功能是散布精微物质以滋养和推动全身运用，为胃传输水谷精液。脾的主要职责在于运化，因此以“升”为德性。脾的部位对应水谷之海，因此容易受湿邪困扰而致病。如果脾的功能有余或不足，导致病邪淫溢或气机郁结，那么水和火两种气都能伤害它。
水邪为病则导致壅滞，壅滞则损伤正气，导致虚弱而不能运化，出现腹部胀满、胃脘疼痛、肠鸣、完谷不化的泄泻、身体沉重等症状；严重时会出现上部大寒的症状。火邪为病则导致津液不濡润，不濡润则损伤血液，导致血枯干燥，胃气变得浓浊（此处指胃中虚火亢盛或燥热），表现为容易饥饿但肌肉萎缩无力、足部软弱不能行走、容易发生抽搐、脚底疼痛、舌根僵硬、进食后呕吐、食物难以下咽、心烦意乱、小便不通、黄疸、脾约（大便干结）等症。
治疗的关键在于常使少阳的温和之气在体内经常流动，这样脾土就能湿润而上升，不受燥邪伤害；脾土强健而运化，不受湿邪伤害。这才是达到了平衡。
然而，脾居于中央，是孤脏，负责灌溉四方，并主管四肢末端。脾生病时，必然会波及其余四脏；而其余四脏有病，也必然依赖脾的滋养。如果脾的功能衰竭，那么四脏就无法生存。这是后天之本的断绝，其危害比先天之根的断绝更为迅速和严重。因此，治疗其他四脏的疾病，不可以不养护脾脏。调和脾胃，是医学中的王道之法。
文中提到腹部胀满、支撑胸胁、下部厥冷上部昏冒，认为过错在于太阴和阳明二经。太阴脾土壅滞，则本经不能运化，导致阳明胃气不能升腾。因此，营卫之气不能升降通达于上下。不能下达于下，则肾气独自下沉，所以下部厥冷；不能升达于上，则肺气不能运行，所以上部昏冒。这是由于中气不足，属于中焦脾胃的病证，所以严重时病邪会深入脾脏。
肾在人体中属于阴中之少阴，顺应天时主掌冬季。因此，太阳寒水之气不归膀胱而归肾。这是因为肾的气机特性，主蛰伏、主归藏。天地收敛闭藏的气机，必然归于这里，所以寒水之气只有肾能主导它。
考虑到肾作为先天的根基，与心火相对待，所以它又被称为阴中之太阴，而先天的真火也蕴含在其中。虽然各自有不同的形体，寒是水的位置属性，但实际上是以火为功能作用。《易经》中坎卦，画一阳爻入于两阴爻之间，体现了体阳而用阴的特性，其性质流行变化；又体现体阴而用阳。人身之肾，其坚硬滑利的是水的形体，其流动变化的是火的功能。具备水火两者，将命门的真火藏在至阴之中，这就是坎卦的形象。
阳气生于阴中，静极生动，能够升发阴精以上奉于心（离宅）。这就是所谓“升坎填离”的奥妙，乃是先天的大根本和大源头。因为火藏在水中，水升向天上，所以常以水为海，以火为龙。水温暖则龙潜藏，水寒冷则龙兴起。因此，肾脏的疾病，不仅仅是水衰被土所克，还有水火两方面的病变。
如湿邪和寒邪过胜，就会出现浮肿、骨痛、阴痹（阴部疼痛）、头项痛、时常眩晕、饥饿但不想吃东西等症状。寒气自伤，则出现清冷厥逆、心情不乐、腹部肿大、小腿肿胀、喘咳、身体沉重、睡中出汗等症状。如果是龙火（相火）为患，则见面色如漆紫黑、咳嗽吐血、喘息有声、心中悬空感、口热咽干、心烦等类症状。这些都是肾脏寒湿淫溢，以及水亏火腾所造成的危害。
至于水藏于土中，而之所以能蛰伏闭藏，实际上是借助了土封固的力量。《内经》说：“肾合精，其主脾。”这意味着封藏的功能必然依赖于脾气。所以不说土克水，而说土生水。这就是前人补肾时，使用六味地黄丸加入茯苓、山药的妙理所在。
先哲曾说：肾家水不足，不要熄灭其火，必须滋阴之源来配合火；肾家火不足，不要损伤其水，必须益火之主来配合水。这话很有深意啊。
The Spleen is located within the Three Yin meridians and serves as the internal master of the Six Meridians. It supports Heaven from Earth, much like the virtue of the earth. Therefore, below "Guangming" (a state of abundant Yang Qi), lies Taiyin (Taiyin Spleen). Taiyin controls the intake and output of the Stomach (the granary) and acts as a storehouse for the Heart Monarch to reserve essence for use.
Thus, its function is to distribute fine nutrients to nourish and facilitate bodily operations, transporting fluid essences for the Stomach. Its primary duty is transportation and transformation, so its virtue is "ascending." Located at the sea of food and fluids, it suffers from dampness. If there is excess or deficiency leading to pathogenic overflow or stagnation, both Water and Fire energies can cause disease.
Water pathology leads to obstruction; obstruction damages Qi, resulting in deficiency and failure to transport, manifesting as abdominal fullness and distension, epigastric pain, borborygmus, undigested stool diarrhea, and heaviness of the body. Severe cases may present with upper-body severe cold. Fire pathology leads to lack of moistening; lack of moistening damages Blood, causing blood dryness and desiccation, while Stomach Qi becomes concentrated (hyperactive/dry-heat), leading to easy hunger but muscle atrophy, weakness of the feet preventing walking, spasms, pain in the soles, stiffness of the tongue base, vomiting after eating, difficulty swallowing, vexation, urinary retention, jaundice, and Pi Yue (Spleen constraint/constipation).
The treatment principle is to constantly maintain the harmonious Qi of Shaoyang moving within, so that Earth remains moist and ascends without injury from dryness, and Earth remains strong and transforming without injury from dampness. This achieves balance.
However, residing in the center, the isolated Zang organ irrigates the four peripheries and governs the four limbs. When diseased, it inevitably affects the other four Zang organs; conversely, when the other four Zang organs are diseased, they must rely on the Spleen for nourishment. If the Spleen fails, the four Zang organs lose their source of life. The destruction of the Postnatal Root is more rapid than the destruction of the Prenatal Root. Therefore, treating diseases of the four Zang organs requires nurturing the Spleen. Harmonizing the Spleen and Stomach is the "King's Way" (gentle and fundamental approach) in medicine.
Regarding symptoms such as abdominal fullness and distension, support across the diaphragm and hypochondrium, lower extremity coldness with upper body dizziness, attributed to disorders of Taiyin and Yangming: Taiyin Earth obstruction causes the meridian itself to fail in transportation, preventing Yangming Qi from ascending. Consequently, Ying and Wei Qi cannot circulate up and down. Failure to descend leads to Kidney Qi sinking alone, causing lower coldness; failure to ascend prevents Lung Qi from circulating, causing upper dizziness. This stems from deficiency of Middle Qi, a disease of the Middle Jiao, which eventually enters the Spleen.
The Kidney is Shao Yin among Yin in the human body, corresponding to the seasonal timing and governing the Winter phase. Thus, the Qi of Solar Cold Water does not return to the Bladder but to the Kidney. This is because the Qi of the Kidney governs hibernation and storage. The converging and storing energy of Heaven and Earth must return here; hence, only the Kidney masters Cold Water.
Considering its position as the root of the Prenatal constitution, opposing Heart Fire, it is also referred to as Tai Yin among Yin, where the Prenatal True Fire is contained. Although they have distinct forms—with Cold being the positional attribute—Fire is actually its functional use. In the I Ching image, Kan (Water trigram) has one Yang line between two Yin lines, representing "Yang in form, Yin in function," with flowing nature; it also represents "Yin in form, Yang in function." In the human body, the firm and slippery aspect of the Kidney is the form of Water, while its mobility is the function of Fire. Possessing both Water and Fire, it stores the True Fire of the Mingmen within extreme Yin, resembling the Kan trigram.
Yang Qi is born within Yin; stillness reaches its limit and generates movement, capable of ascending Yin Essence to offer it to Li (Heart/Fire). This is the subtlety of "Ascending Kan to Fill Li," the great foundation of the Prenatal. Since Fire hides in Water and Water rises to Heaven, Water is often likened to the Sea and Fire to the Dragon. When water is warm, the Dragon hides; when water is cold, the Dragon rises. Therefore, Kidney diseases are not limited to Water deficiency being overcome by Earth, but involve both Water and Fire pathologies.
If Dampness and Cold pathogens prevail, symptoms include edema, bone pain, Yin Bi (pain in the genital/perineal region), headache and neck pain, frequent vertigo, hunger without desire to eat. Self-injury by Cold Qi leads to clear coldness and reversal, unhappiness, abdominal swelling, calf swelling, asthma and cough, body heaviness, and night sweats. If Dragon Fire (Ministerial Fire) causes trouble, symptoms include a face dark as lacquer/purple, hemoptysis, wheezing sounds, a feeling of the heart hanging empty, hot mouth, dry throat, and vexation. These are all harms caused by Cold-Damp excess in the Kidney and the imbalance of Water deficiency with Fire hyperactivity.
Since Water resides within Earth, and the ability to hibernate and store relies on the sealing power of Earth, the Classics state: "The Kidney combines with Essence, governed by the Spleen." This means storage depends on Spleen Qi. Hence, it is said that Earth generates Water rather than overcomes it. This is the profound logic behind previous scholars adding Poria (Fuling) and Dioscorea (Shanyao) to Liuwei Dihuang Wan for tonifying the Kidney.
Ancient sages stated: "When Kidney Water is insufficient, do not extinguish its Fire; instead, nourish the source of Yin to harmonize with Fire. When Kidney Fire is insufficient, do not damage its Water; instead, benefit the Master of Fire to harmonize with Water." There is profound meaning in this.