肾虚不能制火者。此方主之。肾中非独水也。命门之火并焉。肾不虚。则水足以制火。虚则火无所制。而热
证生矣。名之曰阴虚火动。河间氏所谓肾虚则热是也。今人足心热。阴股热。腰脊痛。率是此证。乃咳血之渐
也。熟地黄山茱萸。味浓者也。经曰。味浓为阴中之阴。故能滋少阴补肾水。泽泻味咸。咸先入肾。地黄山药
泽泻。皆润物也。肾恶燥。须此润之。此方所补之水。无形之水。物之润者亦无形。故用之。丹皮者。牡丹之
根皮也。丹者南方之火色。牡而非牝属阳。味苦辛。故入肾而敛阴火。益少阴。平虚热。茯苓味甘而淡者也。
甘从土化。土能防水。淡能渗泄。故用之以制水脏之邪。且益脾胃而培万物之母。壮水之主。以镇阳光。即此药也。
君子观象于坎。而知肾中具水火之道焉。夫一阳居于二阴为坎。此人生与天地相似也。今人入房盛而阳事
易举者。阴虚火动也。阳事先痿者。命门火衰也。真水竭则隆冬不寒。真火息则盛夏不热。是方也。熟地山萸
丹皮泽泻山药茯苓。皆濡润之品。所以能壮水之主。肉桂附子。辛润之物。能于水中补火。所以益火之原。水火
得其养。则肾气复其天矣。益火之原。以消阴翳。即此方也。盖益脾胃而培万物之母。其利溥矣。
节斋云。人之一身。阴常不足。阳常有余。况节欲者少。纵欲者多。精血既亏。相火必旺。火旺则阴愈
消。而痨瘵咳嗽咯血吐血等证作矣。故宜常补其阴。使阴与阳齐。则水能制火。而水升火降。斯无病矣。故丹
溪先生。发明补阴之说。谓专补左尺肾水
也。古方滋补药。皆兼补右尺相火。不知左尺原虚。右尺原旺。若左右平补。依旧火胜于水。只补其左制其右。
庶得水火相平也。右尺相火。固不可衰。若果相火衰者。方宜补火。但世之人火旺致病者。十之八九。火衰成病
者。百无一二。且少年肾水正旺。似不必补。然欲心正炽。妄用太过。至于中年。欲心虽减。然少年斫丧既多。
焉得复实。及至老年。天真渐绝。只有孤阳。故补阴之药。自少至老。不可缺也。节斋先生发明先圣之旨。以正
千载之讹。其功盛哉。但水衰者固多。火衰者亦不少。先天禀赋若薄者。虽童子尚有火衰之证。焉可独补水哉。
况补阴丸中。以黄柏知母为君。天麦门冬为佐。盖黄柏苦寒泄水。天门寒冷损胃。服之者。不惟不能补水。而且
有损于肾。故滋阴降火者。乃谓滋其阴。则火自降。当串讲。不必降火也。然二尺各有阴阳水火互相生化。当
于二脏中各分阴阳虚实。求其所属而平之。若左尺脉虚弱而细数者。左肾之真阴不足也。用六味丸。右尺脉迟
软。或沉细而数欲绝者。是命门之相火不足也。用八味丸。至于两尺微弱。是阴阳俱虚。用十补丸。此皆滋其
先天之化源。实万世无穷之利。自世之补阴者。率用黄柏知母。反戕脾胃。多致不起。不能无遗憾于世。
予特表而出之。以广前人之未备。使医者病者加意于六味八味二方云。
附录十补丸 治肾虚冷。足寒膝软。
五味子 附子（各二两） 山萸 山药 丹皮 桂心 茯苓 泽泻 制鹿茸（各一两）
When Kidney Qi is deficient and unable to control Ministerial Fire, this formula is indicated. The Kidney contains not only Yin Water but also the Fire of the Gate of Life (Mingmen). If the Kidney is not deficient, there is sufficient Yin Water to restrain Yang; however, when deficiency occurs, Fire loses its restraint and heat syndromes arise. This condition is named "Yin Deficiency with Hyperactive Fire," which refers to Liu Wansu's statement that "Kidney deficiency leads to heat." Currently, symptoms such as heat in the soles of the feet, heat in the medial thighs, and pain in the lower back and spine are mostly due to this syndrome, which serves as a precursor to hemoptysis.
Shu Di Huang (Prepared Rehmannia Root) and Shan Zhu Yu (Cornus Fruit) have rich flavors. The *Classic* states: "Rich flavors belong to Yin within Yin." Therefore, they can nourish the Shaoyin channel and tonify Kidney Water. Ze Xie (Alisma Rhizome) has a salty flavor, and salty flavors enter the Kidney first. Shu Di Huang, Shan Zhu Yu, Shan Yao (Dioscorea Rhizome), and Ze Xie are all moistening substances. The Kidney dislikes dryness and requires these moistening agents for nourishment. The water supplemented by this formula is "formless water," and things that moisten all beings are also formless; hence, they are used. Dan Pi (Moutan Cortex) is the root bark of the peony. "Dan" represents the fire color of the South; "Mu" indicates male/yang attributes. With bitter and acrid flavors, it enters the Kidney to astringe Yin Fire, benefits the Shaoyin, and calms deficiency heat. Fu Ling (Poria Sclerotium) has sweet and bland flavors. Sweet flavors transform through Earth, and Earth can prevent water overflow; bland flavors promote diuresis and drainage. Thus, it is used to restrain pathogens in the Water organ and benefit the Spleen and Stomach, cultivating the mother of all things. "Strengthening the Master of Water to suppress Solar Flare" refers to these herbs.
The gentleman observes the image of Kan (☵) and understands the principle of Water and Fire coexisting in the Kidney. One Yang line situated between two Yin lines forms Kan, mirroring human life and heaven and earth. When individuals engage in excessive sexual activity leading to easy erection, it indicates Yin Deficiency with Hyperactive Fire; if impotence occurs, it indicates Decline of the Fire of the Gate of Life. When True Water is exhausted, winter does not feel cold; when True Fire ceases, summer does not feel hot. In this formula, Shu Di Huang, Shan Yu, Dan Pi, Ze Xie, Shan Yao, and Fu Ling are moistening products capable of "strengthening the Master of Water" (tonifying Kidney Yin); Rou Gui (Cinnamon Bark) and Fu Zi (Aconite Lateral Root) are acrid and moistening substances capable of supplementing Fire within Water, i.e., "benefiting the Origin of Fire" (warming the Gate of Life). When Water and Fire are nourished, Kidney Qi recovers its innate foundation. "Benefiting the Origin of Fire to dissipate Yin Shadows" refers to this formula (Jinkui Shenqi Wan). It benefits the Spleen and Stomach and cultivates the mother of all things, offering extensive benefits.
Mr. Jiezai stated: In the human body, Yin is often insufficient, while Yang is often in excess. Moreover, those who practice moderation in desire are few, while those who indulge are many. Once Essence and Blood are depleted, Ministerial Fire inevitably becomes vigorous. Vigorous Fire consumes Yin further, leading to conditions such as consumption, cough, hemoptysis, and hematemesis. Therefore, one should frequently tonify Yin to balance Yin and Yang, allowing Water to control Fire, ensuring Water ascends and Fire descends, thus preventing disease. Consequently, Mr. Danxi elucidated the theory of tonifying Yin, asserting that one should specifically tonify the Kidney Water corresponding to the left Chi pulse. Ancient tonic formulas often tonified both the right Chi Ministerial Fire. They failed to realize that the left Chi is originally deficient and the right Chi is originally vigorous. If both sides are balanced equally, Fire will still prevail over Water. Only by tonifying the left to restrain the right can Water and Fire be balanced. Although the Ministerial Fire on the right Chi should not decline, supplementation of Fire is appropriate only if there is indeed a decline. However, nine out of ten people suffer from diseases caused by vigorous Fire, while less than one percent suffer from deficiency of Fire. Furthermore, young people have vigorous Kidney Water and seemingly do not need supplementation. Yet, due to excessive indulgence during youth, even though desires decrease in middle age, the prior depletion cannot be easily restored. By old age, innate vitality gradually fades, leaving only solitary Yang. Therefore, Yin-tonifying medicines are indispensable from youth to old age. Mr. Jiezai elucidated the intent of the sages and corrected millennia of errors, achieving great merit. Nevertheless, while Water deficiency is common, Fire deficiency is also not rare. Individuals with weak congenital endowment may exhibit signs of Fire deficiency even as children; how can one solely supplement Water? Moreover, in Yin-tonifying pills, Huang Bo (Phellodendron Bark) and Zhi Mu (Anemarrhena Rhizome) serve as sovereign herbs, with Tian Dong (Asparagus Tuber) and Mai Dong (Ophiopogon Tuber) as assistant herbs. Huang Bo is bitter and cold, draining Water; Tian Dong is cold and damages the Stomach. Users not only fail to supplement Water but also damage the Kidneys. Thus, "Nourishing Yin to Descend Fire" means nourishing Yin so that Fire naturally descends; it should be understood as such, without actively attempting to "descend Fire." However, both Chi pulses contain Yin/Yang and Water/Fire, which mutually generate each other. One must differentiate Yin/Yang and deficiency/excess within the two organs and balance them accordingly. If the left Chi pulse is weak, fine, and rapid, it indicates insufficiency of Left Kidney True Yin; use Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia). If the right Chi pulse is slow and soft, or deep, fine, and nearly imperceptible, it indicates insufficiency of Gate of Life Ministerial Fire; use Ba Wei Di Huang Wan (Eight-Ingredient Pill with Rehmannia). If both Chi pulses are weak, it indicates dual deficiency of Yin and Yang; use Shi Bu Wan (Ten-Ingredient Pill). These methods all nourish the congenital source of transformation, providing endless benefits for generations. Since practitioners claiming to tonify Yin generally use Huang Bo and Zhi Mu, which damage the Spleen and Stomach and often lead to untreatable conditions, I regret this state of affairs. I hereby highlight this point to supplement previous works, urging physicians and patients to pay close attention to Liu Wei Di Huang Wan and Ba Wei Di Huang Wan.
Appendix: Shi Bu Wan treats Kidney deficiency with cold, cold feet, and weak knees.
Wu Wei Zi (Schisandra Fruit), Fu Zi (Aconite Lateral Root) (2 liang each); Shan Yu (Cornus Fruit), Shan Yao (Dioscorea Rhizome), Dan Pi (Moutan Cortex), Gui Xin (Cinnamon Twig Heart), Fu Ling (Poria Sclerotium), Ze Xie (Alisma Rhizome), Zhi Lu Rong (Processed Deer Antler) (1 liang each).