天以六为节。地以五为制。其生五。（天元纪大）
河图之教五十有五。而总其数为天五地六。分其数为天五地五。天五者、一三五七九。五奇也。地五者、二四六八
十。五耦也。奇以五乘五。五五二十五。耦以六乘五。五六三十。此所以天五地六也。然而阴阳交互。气运相乘。则天
气反以六。地气反以五。此六节五制之旨。轩岐所述也。盖两仪既奠。而后天以阳而化气。气本无形。凡六合无形化气
之阴阳。皆本于天气。以阴而成质。质处有形。凡六合有形成质之阴阳。皆本于地气。所谓五者。生长化收藏。而成木
火土金水是也。所谓六者。少阳阳明太阳厥阴少阴太阴。以奉寒暑燥湿风火是也。所谓六为节者。天以一元布行于地。
即本地之六位以分化气。是天以六为节也。所谓五为制者。地以坤顺承之化。即本天之五行以作成物。是地以五为制也。
总之天以五而干生。地以六而支生。以五加六而甲子生。天以五用六。地以六承五。此天施地生之大致。而六节五制之
妙义也。其生五者。原其初则五行实生于一气。由其后则万类皆生于五行。故五行有本生之理。有制用之道。其始也天
一生水。天一者纯刚之气也。纯刚之气为全体。故生水。水之为物。一阳居二阴之间。由静而动。由阴而阳。动而之阳。
故地二生火。水火既济。则形成而物畅。故天三生木。阳既畅发。则阳后生阴。自舒而敛。故地四生金。土居中位。成
乎四气。而成功位次反居其后者。土为万物之母。奉天而不居。故必于四气之既成。而后见之也。然土为中宫。为炉鼎。
能以水火为用。水火不得则相射。是以戊己之位。藏于水火。此坎纳六戊。离纳六己。所自来也。故戊己中宫为最尊。
布气育灵。为生物元始。所谓资生于坤也。故以是为南政。君临于上。而水木火金四脏之气环拱之。以其环拱。故谓之
北政。如臣面君也。至其地支辰戌丑未。居四余之偏。兼为四库者。盖以奠定四气。所以始万物终万物而告成功于物后
也。故天虽以五生土。而常以一先四。而首万物。一先四者。即五数之一。而首以土运之义也。此万物所以资始也。地
虽以十成土。而恒以二居五而终阴阳。二居五者。戊癸化火。而适终于地二之数也。此万物所以资生也。生生之本。制
用之道尽矣。
天以“六”作为节律的基准，地以“五”作为制约的准则。万物的化生源于“五”。（出自《天元纪大论》）
河图的数理教导总和为五十五，而将其总数概括为天五地六；将其分项概括为天五地五。所谓“天五”，是指一、三、五、七、九这五个奇数。所谓“地五”，是指二、四、六、八、十这五个偶数。奇数以五相乘，五五得二十五；偶数以六相乘，五六得三十。这就是所谓“天五地六”的道理。然而阴阳相互交错，气运相互叠加，那么天气反而体现为“六”，地气反而体现为“五”。这就是“六节五制”的宗旨，是黄帝与岐伯所论述的内容。
大概两仪确立之后，后天以阳气来化生气化。气本来是没有形状的，凡是六合之中无形的气化之阴阳，都本源于天气。以阴气来形成实质，实质处于有形的状态，凡是六合中有形质的阴阳，都本源于地气。所谓的“五”，是指生长化收藏，从而形成木、火、土、金、水。所谓的“六”，是指少阳、阳明、太阳、厥阴、少阴、太阴，用来对应寒、暑、燥、湿、风、火。所谓的“六为节”，是指天将一元之气布行于地上，即依据本地原有的六位来分化气化，这就是天以“六”作为节律。所谓的“五为制”，是指地以坤德顺承天的变化，即依据本天的五行来成就万物，这就是地以“五”作为制约。
总之，天以“五”来干支相生，地以“六”来支干相生，以“五”加“六”而产生甲子循环。天以“五”运用“六”，地以“六”承受“五”。这是天施予、地生长的基本规律，也是“六节五制”的精妙义理。“其生五”这句话，追根溯源，五行实际上生于一气；从其后发展来看，万物皆生于五行。所以五行既有本源生成的道理，又有制约运用的法则。起初是天一生水，“天一”是纯刚之气。纯刚之气构成整体，所以生水。水这种事物，一阳居于二阴之间，由静变动，由阴转阳，动而趋向于阳，所以地二生火。水火既济，则形体形成而万物通畅，所以天三生木。阳气既然畅发，则在阳后生出阴，由舒展转为收敛，所以地四生金。土居中央位置，成就这四气，而其成功位次反而排在后面，是因为土是万物的母亲，奉行天道而不居功，所以必须在四气既成之后才显现出来。
然而土居中宫，如同炉鼎，能够利用水火。水火不得其用则会相互排斥，所以在戊己之位，藏于水火之中。这就是坎卦纳六戊、离卦纳六己的来源。所以戊己中宫最为尊贵，布散气机养育神灵，是生物的本源起始，这就是所谓“资生于坤”。因此以此作为南政，君主临于上方，而水、木、火、金四脏之气环绕拱卫它。因为它环绕拱卫，所以称为北政，就像臣子面见君主一样。至于地支中的辰、戌、丑、未，居于四方余气的偏位，兼作四库，大概是为了奠定四气，所以始于万物终于万物，在万物之后宣告成功。所以天虽然以五生成土，但常以一先于四，为首领万物。“一先于四”，就是五数中的“一”，以及首先以土运的含义。这是万物所以获得始基的原因。地虽然以十成就土，但恒常以二居于五而终结阴阳。“二居五”，是指戊癸化火，恰好终结于地二的数目。这是万物所以获得滋养的原因。生生不息的根本，制约运用的法则，都在这里穷尽了。
Heaven uses "six" as the measure of its cycles, and Earth uses "five" as the principle of its regulation. The generation of things originates from "five". (From *Tianyuan Ji Dalun*)
The numerical teaching of Hetu sums to fifty-five. Its total number is summarized as Heaven Five and Earth Six; its divided numbers are summarized as Heaven Five and Earth Five. "Heaven Five" refers to the five odd numbers: one, three, five, seven, nine. "Earth Five" refers to the five even numbers: two, four, six, eight, ten. The odds multiplied by five yield twenty-five (5x5); the evens multiplied by six yield thirty (6x5). This is the rationale behind "Heaven Five and Earth Six." However, when Yin and Yang interact and Qi movements multiply each other, Heavenly Qi manifests as "six," and Earthly Qi manifests as "five." This is the purport of "Six Cycles and Five Regulations," as expounded by Huangdi and Qibo.
Once the Two Modes (Liangyi) are established, post-heaven Qi transformation occurs through Yang Qi. Qi is inherently formless. All Yin-Yang transformations that are formless within the Six Harmonies originate from Heavenly Qi. Substance formation occurs through Yin Qi; substance exists in a tangible state. All Yin-Yang transformations that form tangible substances within the Six Harmonies originate from Earthly Qi. The so-called "Five" refers to Growth, Transformation, Harvest, Storage, which constitute Wood, Fire, Earth, Metal, and Water. The so-called "Six" refers to Shaoyang, Yangming, Taiyang, Jueyin, Shaoyin, and Taiyin, which correspond to Cold, Heat, Dryness, Dampness, Wind, and Fire. The phrase "Six as Cycles" means that Heaven distributes the One Yuan Qi onto Earth, utilizing the local six positions to differentiate Qi transformation; thus, Heaven uses "six" as the cycle. The phrase "Five as Regulations" means that Earth, following Kun virtue, receives Heaven's transformation, utilizing the Heavenly Five Elements to accomplish things; thus, Earth uses "five" as the regulation.
In summary, Heaven generates via the Stems using "five," and Earth generates via the Branches using "six"; combining "five" and "six" produces the Jiazi cycle. Heaven employs "five" with "six," and Earth receives "five" with "six." This is the general principle of Heaven bestowing and Earth generating, and the profound meaning of "Six Cycles and Five Regulations." Regarding "Its generation comes from five," tracing back to the origin, the Five Elements actually arise from One Qi; looking forward, all categories of life arise from the Five Elements. Thus, the Five Elements have both the principle of original generation and the way of regulatory application. Initially, Heaven One generates Water. "Heaven One" is pure Gang (firm/strong) Qi. Pure Gang Qi constitutes the whole, hence it generates Water. Water, as an entity, has one Yang residing between two Yins, moving from stillness to motion, from Yin to Yang, moving towards Yang; therefore, Earth Two generates Fire. When Water and Fire achieve mutual interaction (Ji Ji), form is established and things flow freely; therefore, Heaven Three generates Wood. Once Yang is fully expressed, Yin is generated after Yang, transitioning from expansion to contraction; therefore, Earth Four generates Metal. Earth occupies the central position, completing the four Qi elements. Its success appears later because Earth is the mother of all things, serving Heaven without claiming credit, so it manifests only after the four Qi elements are complete.
However, Earth resides in the Central Palace, acting like a furnace or tripod, capable of utilizing Water and Fire. If Water and Fire do not function properly, they repel each other. Therefore, at the positions of Wu and Ji, they are hidden within Water and Fire. This is the origin of Kan Gua containing Liu Wu and Li Gua containing Liu Ji. Thus, Wu-Ji Central Palace is most revered, distributing Qi to nourish spirits, serving as the primordial beginning of creation, which is what is meant by "nourished by Kun." Hence, this serves as Southern Politics, with the Sovereign ruling above, while the Qi of the four Zang organs—Water, Wood, Fire, and Metal—surround and support it. Because they surround and support, it is called Northern Politics, like ministers facing the sovereign. As for the Earthly Branches Chen, Xu, Chou, and Wei, occupying the peripheral positions of the four residual Qi and serving as the four Storehouses, they likely serve to stabilize the four Qi elements, thus beginning all things and ending all things, announcing success after the completion of things. Therefore, although Heaven generates Earth using five, it often places "one" before "four" to lead all things. "One preceding four" refers to the "one" in the number five and the meaning of leading with Earth Qi. This is why all things receive their origin. Although Earth completes Earth using ten, it constantly places "two" at "five" to conclude Yin and Yang. "Two at five" refers to Wu and Gui transforming into Fire, which恰恰 concludes at the number of Earth Two. This is why all things receive their nourishment. The root of continuous generation and the way of regulatory application are fully exhausted here.