相火之下。水气承之。水位之下。土气承之。土位之下。风气承之。风位之下。金气承之。金位之下。火气承之。
君火之下。阴精承之。亢则害。承乃制。制则生化。化则盛衰。害则败乱。生化大病。（六微旨大论）
此章王马滑张诸家。寻其说而不得。乃以气交之变释之。谓少阳火生。终为溽暑。不知此专气之次。非承制之的义。
夫承制者。皆元气之所本有。即其所生之理。备有生化之道。初非矫强挽回也。阴阳动静。皆涵天地之元贞。故其生物
也。贵其专精。尤忌其一往。是以阴中有阳。阳中有阴。如易卦之飞伏。飞下即伏。伏上即飞。故乾卦六阳。其下皆坤。
坤卦六阴。其下皆干。阴阳之精义。本是如此。吾故于天道之六气。各有中见。而知地节之六位。自亦有为之内者。以
为参和。是故位之下即内之义也。相火于节。主四五月。为六阳之元。而其时之水气正盛。前为谷雨。后及芒种。皆有
水泽流溢。以助调相火。是水承之义也。至于水位。则大雪冬至小寒之日矣。时当寒 。而正为物所归藏。其所以归藏
者土也。有藏而后有生。故有下起元。而得回地中之一阳。是土承之义也。若夫土生万物。而亢则有水火二至。亢于湿。
则水至而流。亢于燥。则火至而坚。苟非风木和柔之气。内居其间。何以使土脉和动。故土旺长夏。而木正向荣。是其
义也。风为春木。由甲坼条舒。以至于长茂坚成。必有金气以收之。是以榆荚之落。见于春时。亦其义也。金位兑说。
而神主蓐收。若无火气之微布。则凄冽之气。即申酉而寒 矣。乃由白露方凉。渐于寒露。暨于霜降。于时生物。及多
至于成。但火犹有存者。此知金下有火也。至若君火所承。则不曰水气。而独曰阴精。阴精者。生气之华也。地上三阴
之全气也。其火不主夏令。而首出显明。当三月之和。地气腾上。阴精所奉。莫备于此。是犹众职效用。而君自端拱也。
盖亢者专气之一往。承者相济之参和。非以其相反而相犯为制也。唯其内有以相承相济则元气足。而生生浓。故曰制。
生则化。盖生而无制则化偏。生而有制则化备也。自此而列一任加临交变。有余不足。至与未至。虽外有此列。以乘除
其间。而其本生之气。自不败不乱。故曰外列盛衰也。若专气一往而之厥所。承则本气已见败乱。安得不为生化大病乎。
Below the Fire of Minister (Xianghuo), the Qi of Water (Shuiqi) acts as its support and restraint. Below the position of Water, the Qi of Earth (Tuqi) acts as its support and restraint. Below the position of Earth, the Qi of Wind (Fengqi) acts as its support and restraint. Below the position of Wind, the Qi of Metal (Jinqi) acts as its support and restraint. Below the position of Metal, the Qi of Fire (Huoji) acts as its support and restraint.
Below the Fire of Sovereign (Junhuo), the Yin Essence (Yinjing) acts as its support and restraint. When in a state of hyperactivity (Kang), harm ensues; only with support and restraint (Chengzhi) is balance maintained. With restraint, transformation and generation (Shenghua) occur orderly; with orderly transformation, there is measure in waxing and waning. If harm occurs, chaos and disorder prevail, leading to severe diseases. (From *Suwen: Chapter 21, Discussion on the Six Subtle Principles*)
In this chapter, scholars such as Wang Bing, Ma Shi, Hua Shou, and Zhang Jingyue sought its meaning but failed to grasp it thoroughly. They interpreted it through the concept of "changes at the intersection of Qi," arguing that the generation of Shaoyang Fire eventually manifests as humid heat and summer heat. They did not realize that this passage specifically discusses the sequence of Qi, which is not the precise meaning of the theory of support and restraint.
The concept of support and restraint is inherent in Yuan Qi (Primal Qi); it is the principle of generation itself, containing within it the path of transformation and generation. It is not initially about forcing a reversal or recovery. The movement and stillness of Yin and Yang both contain the primal integrity of Heaven and Earth. Therefore, when they generate all things, they value specialization and focus, and particularly avoid proceeding blindly without return. Thus, Yin contains Yang, and Yang contains Yin. This is like the flying and hiding (Feifu) in I Ching hexagrams: what flies down hides, and what hides up flies. In the Qian Hexagram (Pure Yang), below the six Yang lines lies the essence of Kun (Yin); in the Kun Hexagram (Pure Yin), below the six Yin lines lies the essence of Qian (Yang). The profound meaning of Yin and Yang is inherently thus.
Therefore, regarding the Six Qi of Heaven's Dao, each has a "Zhongjian" (Middle Manifestation/Interior-Exterior pairing). Knowing this, we understand that the Six Positions of Earth's Jie (Solar Terms) also have internal mechanisms acting as parameters for harmony. Hence, "below the position" implies an "internal" meaning.
Minister Fire governs the fourth and fifth months in the solar terms. It is the origin of the six Yang phases. At this time, the Qi of Water is vigorous. Preceded by Guyu (Grain Rain) and followed by Mangzhong (Grain in Ear), water marshes overflow, assisting in regulating Minister Fire. This illustrates the meaning of Water supporting Minister Fire. As for the position of Water, it corresponds to the days of Daxue (Major Snow), Dongzhi (Winter Solstice), and Xiaohan (Minor Cold). The weather is cold, yet it is precisely when all things return to storage. The reason for this storage is Earth. Only after storage can there be generation; thus, the primal Yang rises from underground, recovering the one Yang within the earth. This illustrates the meaning of Earth supporting Water.
As for Earth generating all things, if it becomes hyperactive, two extremes appear: Water and Fire. Hyperactivity in dampness leads to water overflowing; hyperactivity in dryness leads to fire hardening. Unless the soft and gentle Qi of Wind-Wood resides internally between them, how could the Earth pulse remain harmonious and mobile? Therefore, Earth prospers in Late Summer, while Wood Qi is towards flourishing. This is the underlying principle.
Wind corresponds to Spring Wood. From the cracking of seeds and stretching of branches to lush growth and firm formation, there must be Metal Qi to harvest and restrain. Thus, the falling of elm pods in spring also follows this principle. The position of Metal corresponds to the Dui Hexagram (Joy), and its spirit governs "Rushou" (Autumn Harvest/Slaughter). Without the subtle distribution of Fire Qi, the chilling air would become severely cold during Shen and You hours (3 PM - 7 PM). However, from Bailu (White Dew) bringing coolness, gradually to Hanlu (Cold Dew) and Shuangjiang (Frost Descent), living things mostly reach maturity. Yet, some Fire Qi remains. This indicates that Fire exists below Metal.
Regarding what supports Sovereign Fire, it is not called Water Qi, but exclusively Yin Essence. Yin Essence is the essence of Sheng Qi (Vital Qi) and the complete Qi of the three Yin levels on Earth. Sovereign Fire does not govern Summer; rather, it first appears brightly. During the harmony of the third month, Earth Qi ascends. The offering of Yin Essence is most complete here. This is akin to various officials performing their duties while the Sovereign sits upright and governs without action (Wuwei).
"Hyperactivity" (Kang) refers to the blind forward progress of exclusive Qi. "Support" (Cheng) refers to mutual assistance and harmonization. It is not about restraint through opposition and conflict. Precisely because internally there is mutual support and assistance, Yuan Qi becomes sufficient, and the generative process becomes dense. Hence, it is called "restraint." Generation leads to transformation. If there is generation without restraint, transformation becomes biased; if there is generation with restraint, transformation becomes complete. From this point on, regardless of the superimposed changes, whether excess or deficiency, arrival or non-arrival, although external manifestations exist to multiply and divide within these processes, the original generative Qi itself will not decay or become chaotic. Hence, it is said that externally, waxing and waning are displayed. If exclusive Qi proceeds blindly to its extremity, and the supporting original Qi shows signs of decay and chaos, how can it not result in major diseases of transformation and generation?