心之合脉也。其荣色也。其主肾也。肺之合脉也。其荣毛也。其主心也。肝之合脉也。其荣爪也。其主肺也。脾之
合肉也。其荣肌也。其主肝也。肾之合骨也。其荣发也。其主脾也。
五脏藏神主用。而职有贵贱。事有相使。内经明之矣。而于五行之相克。脏之受制。经反以为主而用之。则何也。
盖五
行之妙。每以相制为生。故内经于此特明五脏之养。受生之本。其道固有以逆而不以顺者。乃非以为克而以为生也。夫
心藏血脉。自当以合脉为主。而偏主于所畏之水。此养心之法也。何则。心以神用。则必取金多而用物宏。苟非太冲之
精腾上而调护之。则神空而无所丽。是神之所丽。唯有阴精承之。以为之济也。所以然者。心本纯阳。而其象反为 女。
内自含阴。故其象又为月窟。参同为 女之性冤而最神。得火则飞。不见埃尘。必使清静有匹以镇之。俾婴儿谐于 女。
而后月窟天根通其往来也。天使 女之有匹者。非其主之者耶。老氏云。上善若水。水善下而不争。此持心之道也。天
根月窟之往来。 女婴儿之谐偶。此养心之妙也。此可知肾之为心主矣。肺主气。而其象应秋。 敛清肃。肺之性与用
也。若寒凉过甚。则太和失而元气遂伤。此必有所相济以生其和。而后元气得行。能生其和者。非心德之暖乎。唯有火
德之暖。以益金体之清。是以金为丽泽。而沛雨露于天河之上。凡金之不燥不溢。得以治节体元加于众物之表。而不若
气上逆者。此物此志也。肝厥阴。而职风木。其气兆甲于艮。而凋落于兑。则燥金固所畏也。然肝之少阳。其少也苦稚。
其盛也苦怒。其横溢也苦逆。调之者唯在其金。而轻重治之。使稚者渐坚。怒者遽平。逆者敛缉。而后乃成其为少阳之
盛德。故其主肺也。至若太阴脾土。以浓德载物。而育之长之。尝苦于木之克制。是木为脾 也。然土泽而滞。每有水
火二窒。水湿则土泥而不生。火燥则土坚而不荣。唯有厥阴之气。以疏通之。而达其升德。则水不为濡。火不为燥。而
后能奔走诸经。以行津液。是脾不可一日不主肝也。至于土为肾主。则更有妙于此者。夫水由地中行者也。以流为性。
以险为习。惟是生于天。而涵于土。故源泉不竭。而泛溢无虞。是土能制水。正土能养水也。知乎此。则知肾之所以能
蛰藏者。固非土莫主也。由是言之。养心者莫若补肾。保肺者莫若宁心调肝者在于敛肺。扶脾者在于达肝。而滋肾者在
于葆脾。相克之道。转而相生。此五行五德之妙也。
The Heart is harmonized with the Mai (Vessels). Its flourishing manifestation is in the complexion. Its controlling organ is the Shen (Kidney). The Lung is harmonized with the Mai (Vessels). Its flourishing manifestation is in the hair. Its controlling organ is the Xin (Heart). The Liver is harmonized with the Mai (Vessels). Its flourishing manifestation is in the nails. Its controlling organ is the Fei (Lung). The Spleen is harmonized with the Rou (Muscles). Its flourishing manifestation is in the Ji (Flesh/Muscle tissue). Its controlling organ is the Gan (Liver). The Kidney is harmonized with the Gu (Bones). Its flourishing manifestation is in the Fa (Hair). Its controlling organ is the Pi (Spleen).
The Zang organs store the Shen (Spirit) and govern functions, yet their duties have distinctions of nobility and baseness, and their affairs involve mutual direction. This has been clearly elucidated in the Nei Jing (Inner Canon). However, regarding the theory of Wu Xing (Five Elements) mutual overcoming, and how Zang organs are subjected to others, the Classic instead employs this concept as "Master" (Zhu). Why is this so?
Generally, the subtlety of Wu Xing (Five Elements) lies in generating life through mutual restriction. Therefore, the Nei Jing (Inner Canon) specifically clarifies here the nourishment of the five Zang organs, revealing the root of generation. The principle indeed involves methods that are contrary rather than compliant, but this is not for the sake of overcoming, but for the sake of generating life.
The Xin (Heart) stores blood vessels; logically, it should prioritize its harmonized partner, the Mai (Vessels), yet it peculiarly prioritizes the Water organ it fears. This is the method of nourishing the Xin (Heart). Why? Because the Xin (Heart) operates through Shen (Spirit), it necessarily requires abundant Jin (Metal/Lung) and macroscopic function. If the essence of Tai Chong (Kidney Essence) did not ascend to regulate and protect it, the Shen (Spirit) would be empty and have no place to attach. Thus, what the Shen (Spirit) attaches to is solely Yin Jing (Essence) receiving it, providing assistance. The reason for this is that the Xin (Heart) is originally pure Yang, yet its image resembles "Nu" (Female/Yin). Internally containing Yin, its image is also called "Yue Ku" (Cave of the Moon). The *Can Tong Qi* states: "The nature of Nu is grievous yet most spiritual; obtaining Fire, it flies, seeing no dust." It must be made quiet and matched to suppress it, allowing the Infant (Kan/Yang within Yin) to harmonize with Nu (Li/Yin within Yang), so that Yue Ku (Moon Cave) and Tian Gen (Heaven Root) can communicate freely. That Heaven allows Nu to have a match—is it not determined by its Master? Laozi said: "The highest good is like water; water benefits all things and does not compete." This is the way to maintain the Xin (Heart). The interaction between Tian Gen and Yue Ku, and the harmony between Infant and Nu—this is the subtlety of nourishing the Xin (Heart). From this, we know that the Shen (Kidney) serves as the Master of the Xin (Heart).
The Fei (Lung) governs Qi, and its image corresponds to Autumn, possessing contracting and clearing properties. This is the nature and function of the Fei (Lung). If coldness and coolness are excessive, then Tai He (Great Harmony) is lost, and Yuan Qi (Original Qi) is injured. There must be mutual assistance to generate harmony, after which Yuan Qi (Original Qi) can circulate. What generates harmony? Is it not the warmth of the De (Virtue/Function) of the Xin (Heart)? Only the warmth of Huo (Fire/Virtue) can benefit the Qing (Clear/Pure) constitution of Jin (Metal). Thus, Jin (Metal) becomes a moistened marsh, pouring rain and dew above the Heavenly River. Whenever Jin (Metal) is neither dry nor overflowing, able to govern and regulate its primal body upon all things, without Qi rising counterflow, this is due to this intention.
The Gan (Liver) belongs to Jue Yin and governs Wind-Wood. Its Qi manifests at Gen (Northeast/Spring) and withers at Dui (West/Autumn); thus, Dry Metal (Fei/Lung) is naturally feared. However, the Shao Yang (Lesser Yang) Qi within the Gan (Liver) suffers from immaturity when young, from anger when vigorous, and from rebellion when overflowing. Regulating it relies solely on Jin (Metal), treating it with appropriate weight to make the immature firm, the angry calm, and the rebellious restrained, thereby achieving the great virtue of Shao Yang. Hence, the Fei (Lung) is the Master of the Gan (Liver).
As for the Tai Yin Pi (Spleen-Earth), it carries things with dense virtue, nurturing and growing them, often suffering from Wood's control; thus, Wood is the Master of Pi (Spleen). However, Earth is moist and stagnant, often obstructed by Water and Fire. Water dampness makes Earth muddy and unproductive; Fire dryness makes Earth hard and barren. Only the Qi of Jue Yin (Gan/Liver) can dredge it, reaching its ascending virtue, so that Water is not overly damp and Fire is not overly dry, allowing it to run through the meridians to transport Jin Ye (Body Fluids). Thus, the Pi (Spleen) cannot be without the Master of the Gan (Liver) for a day.
Regarding Earth serving as the Master of the Shen (Kidney), there is an even greater subtlety. Water flows within the earth, taking flow as its nature and danger as its habit. Only by being born from Heaven and nurtured by Earth can the spring source be inexhaustible and flooding be without worry. This means Earth controls Water, precisely because Earth nourishes Water. Understanding this, one knows that the Shen (Kidney)'s ability to hibernate and store is primarily governed by Earth.
From this perspective: To nourish the Xin (Heart), nothing is better than tonifying the Shen (Kidney); To preserve the Fei (Lung), nothing is better than calming the Xin (Heart); To regulate the Gan (Liver), one must restrain the Fei (Lung); To support the Pi (Spleen), one must unblock the Gan (Liver); To nourish the Shen (Kidney), one must protect the Pi (Spleen). The path of mutual overcoming turns into mutual generation. This is the subtlety of the Five Elements and Five Virtues.