《天原發微》Vol. 3

Chapter "Mysterious Primordiality" in Volume 3 of Tianyuan Fawei, compiled by Bao Yunlong (courtesy name Jingxiang) of Luzhai and collated by Fang Hui (courtesy name Wanli) of Xugu, primarily explores the fundamental nature and operational principles of heaven and earth.

Zhu Xi (Master Zhu) states in Zhouyi Benyi: The characteristic of Yang Qi is strength and vigor, with its grandest manifestation being heaven; the nature of Kun (earth) is docility, with its most extensive presentation being the earth. As described in poetry: Looking up at the vast heavens, one can traverse ten thousand miles in an instant; gazing down at earthly forms, silence has preserved them for millennia. Thus, we comprehend the robust and yielding essence of heaven and earth.

All things in the cosmos experience decay and cessation, yet celestial motion never halts—progressing one degree daily without interruption. Unlike earth's fixed form, heaven's domain encompasses all above ground—when earth recedes a foot, heaven expands a foot, though this remains invisible to human eyes. The light, clear Qi ascends to form heaven, circular and perpetually moving, enveloping the central, stationary square of earth. All heavy, turbid descending matter consists of dregs condensed from heavenly Qi.

Tracing the origin, there was initially only undifferentiated primordial Qi, which later divided into Yin and Yang. Yang can encompass Yin, but Yin cannot contain Yang—hence Qian (heaven, Yang) embraces Kun (earth, Yin), forming the triad of cosmic forces. Earth resides within heaven, and earthly Qi fundamentally manifests heavenly Qi. Zhang Zai (Master Zhang) said: The void is the progenitor of heaven and earth; both emerge from emptiness. The Dao takes ultimate emptiness as substance—metal rusts, mountains crumble, all forms eventually perish, yet the Taixu (cosmic void) remains immutable, making it the truest existence. Heaven silently nurtures all beings—this represents the supreme state. He added: Emptiness appears devoid yet is the source of all things.

Shao Yong (Master Shao) proposed: Heaven differentiates creation from "Oneness." Originally whole as one, heaven divides into two with earth's emergence; originally a single stroke (Yang line), Yang splits into two strokes (Yin line) with Yin's appearance. Thus, all phenomena follow this pattern: waning and waxing, front and back—these are natural laws beyond human alteration. The so-called "no-thing" state of the primordial realm requires no artificial arrangement to manifest spontaneously. Shao Yong further noted: In the primordial realm, not even the initial stroke exists. Once "One" appears, it generates two, four, eight, up to three hundred eighty-four transformations—all arising naturally, not by design. He once asked Cheng Yi (Yichuan): "Do you know thunder's origin?" Cheng replied: "I do." Shao responded: "You do not." This exchange subtly reveals epistemological hierarchies in categorical understanding.

This scripture explores the fundamental principles and interrelationships of heaven and earth's operations. Shao Yong (styled Yaofu) posited that cosmic transformations originate from the most primordial source. The genesis of thunder arises from the "Heavenly Root" (cosmic origin), manifesting the creative principle of "one dividing into two."

Heaven and earth exist in mutual dependence: heaven relies on physical form (earth) for its existence, while earth depends on heavenly qi for its movement. Essentially, heaven differentiates into earth, and earth further differentiates into myriad beings, yet the Dao (the fundamental cosmic principle) remains indivisible. Ultimately, all things return to earth, earth returns to heaven, and heaven returns to the Dao.

Cheng Hao (Elder Cheng) and Cheng Yi (Younger Cheng) elaborated: heavenly qi descends to nourish the earth, and all earthly growth originates from heavenly qi. Zhang Zai viewed emptiness as qi itself, with the space between heaven and earth completely permeated by qi. Zhu Xi described heaven as resembling a spinning pellet, with its north and south poles serving as fixed axes—the rotating portion having no solid substance, rising and falling endlessly like a whirlwind. Earth forms from the congealed dregs of qi, suspended in space by rotating currents without falling.

The Yellow Emperor once asked Qibo: "Does the earth have supports?" Qibo replied: "It is upheld by great qi," confirming these perspectives. Detailed analysis reveals: the Qian hexagram (representing heaven) consists of an unbroken line symbolizing fullness, while the Kun hexagram (representing earth) divides into two broken lines symbolizing emptiness. Earth's form resembles lungs—externally solid yet internally hollow. When heavenly qi ascends, earthly qi parts to receive it, allowing even metal and stone to penetrate. Heaven's form resembles bellows, with outer skin enclosing vast qi. The "Monthly Ordinances" records that during early spring, heavenly qi descends while earthly qi rises, creating cyclical interaction.

Through multiple philosophers' discourses, this passage elucidates ancient understandings of celestial-terrestrial structure, operational laws, and their mutual relationships, embodying the Daoist cosmological view of qi transformation and heaven-earth resonance.

This scripture primarily elucidates the generative process of heaven, earth, and all things, along with the Dao of Yin-Yang transformation.

From the eleventh lunar month to the fourth month, Yang Qi (vital energy) steams upward from beneath the Kun (Earth) realm, much like rice being steamed. The fifth month marks the emergence of Yin Qi, and by the seventh month, a pattern forms with three Yin forces below and three Yang forces above. At this stage, celestial Qi ascends while terrestrial Qi descends, causing the energies of heaven and earth to cease circulation—thus forming the enclosed state characteristic of winter.

In the primordial beginnings, heaven and earth contained only the two energies of Yin and Yang in dynamic interaction. Through intense friction between them, impurities were generated. These impurities precipitated to form the earth, akin to sediment consolidating into land from water. Observing mountain ranges from above reveals formations resembling frozen waves or sand dunes shaped by tidal surges. The most intense fiery Qi gave rise to wind, thunder, lightning, and celestial bodies such as the sun, moon, and stars. Heaven consists of nine layers, with purer and more refined Qi ascending to higher levels. This vigorous and unyielding pure Qi constitutes the essence of heaven, perpetually rotating in motion, casting impurities toward the center where they coalesced into the earth.

Shao Yong (Master Shao) remarked: "The earth has a concrete form, yet primordial Qi is boundless." The Dao is the root of all things in heaven and earth, and from the perspective of the Dao, even heaven and earth are merely one among the myriad beings. The transformations of Yin and Yang manifest the Dao (cosmic principle), with heaven and earth being their grandest expression. All things receive their existence from the interplay of these celestial and terrestrial energies. Each individual entity contains within it the complete Taiji (Supreme Ultimate, the cosmic origin). Thus, though heaven and earth appear vast in form, from the standpoint of the Dao, they are but a single phenomenon within the Taiji.

Shu Guangwei, a Daoist master of the Eastern Jin dynasty, employed vivid analogies to illustrate relative motion: "When observing the moon amid clouds, it appears as though the moon moves while the clouds remain still; when aboard a boat, one perceives the water as flowing while the vessel seems stationary." Zhou Dunyi (Master Zhou) pointed out that in observing how heaven and earth give birth to the myriad things, each entity embodies the core principle of cosmic order—what the Yijing (Book of Changes) describes as "the Dao of Qian (Heaven) transforms and perfects, rectifying the nature and destiny of all." If one reflects upon the arising of virtuous thoughts within oneself, this truth can be realized. Animals, possessing blood and Qi, are capable of perception, while plants, though seemingly devoid of awareness, likewise embody the principles of heaven and earth.

This passage explores the ceaseless natural rhythms of heaven and earth, revealing the core concept of the "Heart of Heaven and Earth" within them.

The text begins with examples from nature: plants wither when damaged, fish swim freely in water—these phenomena suggest all things possess a certain innate intelligence. When Cheng Hao (Mingdao) and Zhou Dunyi (Lianxi) observed lush vegetation in their courtyards, they spoke of wishing to constantly witness the Creator's vitality; when keeping fish in garden ponds, they sought to observe all beings in their natural joy—such is the bearing of those who have attained the Dao. Thus through quiet contemplation of all things, one may comprehend nature's true essence.

Cheng Yi (Yichuan) and Zhu Xi (Zhuzi) held that heaven and earth fundamentally exist to nurture all creation. The tenth month represents the season of pure Yin (Kun hexagram), yet within extreme Yin arises Yang—deep within already stirs the first movement of Yang in the Fu hexagram. This faint Yang energy resembles a fetus in the womb, invisible yet already present. Viewed through phenomenal manifestations, it's as if Kun's bottom line suddenly transforms into Zhen hexagram—just as still mountains (Gen hexagram) when overturned reveal thunder's (Zhen hexagram) vibration. Here heaven and earth's life-giving intention becomes clearly visible.

The Qi of heaven and earth circulates endlessly like a millstone ceaselessly producing goods, though what's generated varies in refinement and beauty. The changing seasons and flourishing life may appear naturally spontaneous, yet true randomness would produce chaos—cows birthing horses, peach trees blossoming with plum flowers. In truth, celestial movements follow constant principles governed by the "Divine Emperor" (supreme sovereign). Ancient texts consistently use "Di" (帝) when referring to this governing function and "Tian" (天) when describing all-encompassing coverage. Zhang Shi (Nanxuan) cautions against mistaking the blue sky for heaven's true essence—one must realize it through daily conduct. Each nascent thought is witnessed by the Supreme Deity (Shangdi).

Through natural phenomena and hexagram transformations, this passage elucidates the Daoist teaching that "heaven and earth possess great beauty yet speak no words," emphasizing the need to perceive creation's mysteries within subtle details.

When the human mind deviates even slightly, it triggers agitation and anger. Zhu Xi (Master Zhu) taught that one must comprehend both the natural spontaneity (Wuwei) of things and their inherent principles. Heaven envelops Earth, and its function is simply to transform and generate all beings—this is what we call the "mind of no-mind" (appearing without will yet containing universal patterns).

To believe that blessings reward good deeds and punishments strike evil as if controlled by some ruler, or to think that wind, rain, thunder, and the blooming and withering of flowers are manipulated by spirits—these are misunderstandings. In truth, all men embody the Qian (Yang) energy, and all women embody the Kun (Yin) energy. From the vastest to the minutest, all things are permeated by this Qi (vital energy). Even the tiniest object carries the characteristics of Qian and Kun.

The sounds of all things arise from opening and closing; their principles emerge from movement and stillness; their numbers derive from odd and even; their forms manifest as square and round—all originate from these two fundamental modes of Qian and Kun. Viewed as form, we call it "Heaven"; as sovereign, we call it "the Emperor"; as function, we call it "spirits and deities"; as mysterious operation, we call it "divine." Heaven and Earth are the outer shell of Qian and Kun, while Qian and Kun are the inner essence of Heaven and Earth—all are different expressions of the same Qi.

The growth of all things follows natural laws, which cannot be realized without Heaven's supreme vigor (ultimate strength). Beings originating from Heaven grow upward, like animals with heads raised; those rooted in Earth extend downward, like plants with branches and leaves descending; birds and beasts mostly hold their heads horizontally, hence their limited wisdom. The Dao of Heaven resembles the human head, from which countless things are transformed below.

Fundamentally, all things share the same principle but differ in their Qi constitution; in concrete form, their Qi may appear similar, yet their principles are entirely distinct. For instance, humans and animals alike sense warmth, cold, hunger, and thirst, and seek benefit while avoiding harm—this is similarity in Qi. But ants exhibit the righteousness of ruler and subject, while tigers and wolves show the benevolence of parent and child—these ethical norms (Li) are hard to find in other creatures. Heaven and Earth are like a shell enclosing all things, while Qian and Kun constitute their inner nature, endowing each being with unique attributes.

The Western Inscription states that Qian is the father and Kun the mother, and humans must fulfill their filial duties within this framework. Qian represents Yang, Kun represents Yin, and the Qi of Heaven and Earth fills the cosmos.

This scripture explores the philosophical concepts of cosmic generation and the origin of all things. It first explains that all phenomena between heaven and earth are fundamentally rooted in Qian (the masculine, active principle) and Kun (the feminine, receptive principle). Qian's nature is strong and vigorous, while Kun's is gentle and yielding. The will of heaven and earth operates through Qi (vital energy), through which humans and all creatures receive their respective inherent natures. Humans obtain the complete essence of both innate nature (xing) and life force (ming), thus becoming the most spiritual of all beings; other creatures receive only partial characteristics, possessing merely the basic nature of material existence.

Zhang Zai (Master Zhang) proposes: The Taixu (primordial void, cosmic origin) gives rise to the concept of heaven, while the transformations of Qi form the concept of Dao (the Way). The union of Taixu and Qi produces the concept of innate nature (xing), and the combination of nature with consciousness generates the concept of mind (xin). Zhu Xi (Master Zhu) explains that Taixu represents the totality of the cosmos, encompassing all phenomena including the interplay of Yin-Yang and natural manifestations. Taixu resembles the great circle in the Taiji (Supreme Ultimate) diagram—though Qi has tangible forms while Taixu is formless and traceless, the principles (li) are inherently contained within it. The cognitive faculty of the mind arises from the ethereal and numinous quality of Qi, enabling humans to comprehend and apply these principles.

Shao Yong (Master Shao) asserts: The interaction of Yin and Yang produces heaven, while the interplay of strength and softness generates earth. The "Li Yun" chapter records that ritual systems originate from Taiyi (the supreme unity, cosmic origin), which differentiates to form heaven and earth. Cosmic evolution unfolds in four stages: the Taiji phase (where Qi is not yet manifest), the Taichu phase (initial formation of Qi), the Taishi phase (emergence of forms), and the Taisu phase (materialization). Heaven and earth are the grandest manifestations: heaven arises from the dynamic movement of Taiji, producing Yang Qi (light and clear, ascending), which contains the latent essence of Yin, manifesting as the sun, moon, and stars; earth emerges from the quiescent state of Taiji, generating Yin Qi (heavy and turbid, descending), which holds the latent essence of Yang, manifesting as water, fire, soil, and stone. This exposition delineates the generative process of li (principles), Qi (energy), xing (forms), and zhi (material substance).

This passage elucidates the principles of cosmic generation and the transformations of Yin-Yang. Fundamentally, the movement of Taiji (the Supreme Ultimate, cosmic origin) generates the two Qi of Yin and Yang, whose interaction forms heaven and earth. Specifically: when movement first begins, it produces Yang Qi; when movement reaches its extreme, it transforms into Yin Qi. The mutual interaction of Yin and Yang constitutes the operational patterns of heaven—thus it is said that Yin-Yang generates heaven. When stillness first begins, it produces gentle Qi; when stillness reaches its extreme, it transforms into firm Qi. The mutual interaction of gentleness and firmness constitutes the operational patterns of earth—thus it is said that firm-gentle generates earth.

From the perspective of the singular Qi of heaven and earth: Yang Qi ascends from below, representing the process of growth—as Yang Qi increases, it diminishes Yin Qi. Yin Qi descends from above, representing the process of decline—as Yin Qi increases, it diminishes Yang Qi. Viewed separately as two Qi: what ascends from below is Yang Qi, emerging from the earth, gradually forming the Qian trigram (representing heaven) from the Zi hour (midnight) to the Si hour (mid-morning), reaching its zenith at the Wu hour (noon) where it begins generating Yin Qi to support Yang Qi. The movement of Yang Qi forms heaven's patterns, with heaven rotating leftward. What descends from above is Yin Qi, emerging from heaven, gradually forming the Kun trigram (representing earth) from the Wu hour to the Hai hour (late night), reaching its zenith at the Zi hour where it begins generating Yang Qi to support Yin Qi. The movement of Yin Qi forms earth's patterns, with earth rotating rightward.

Heaven nurtures all things, while earth brings them to completion. Both the Qian and Kun trigrams employ six lines each, with the number six occupying the central position. Advancing six steps and retreating six steps—in advancement it marks the end, in retreat it marks the beginning. The conclusion of day is the commencement of night; the conclusion of night is the commencement of day. Understanding this alternation of day and night allows one, through the numerological deductions of the Yijing (Classic of Changes), to thoroughly comprehend the beginning and end of heaven-earth's operations, grasping the patterns of Yin-Yang's waxing-waning and flourishing-declining.

Furthermore: the Qian and Kun trigrams establish the upper and lower orientations, while the Kan (water) and Li (fire) trigrams arrange the left and right positions. Heaven manifests four images (young and mature Yin and Yang), and earth likewise manifests four images (young and mature firmness and gentleness); heaven has eight phenomena (including sun, moon, stars, and constellations), and earth also has eight phenomena (including water, fire, soil, and stone). Heaven and earth interlock, while Yin and Yang interact. Heaven governs operation, manifesting as seasonal transitions; earth supports all beings, nurturing diverse life. In the Pre-Heaven Bagua arrangement, the four trigrams Qian, Kun, Kan, and Li correspond respectively to the four cardinal directions of Zi, Wu, Mao, and You, governing heaven and earth. Thus all phenomena—the opening-closing of heaven-earth, the rising-setting of sun-moon, the cycling of seasons, lunar phases, day-night lengths, and celestial movements—are determined by these four fundamental images and numbers. In heaven this manifests as transformations of young and mature Yin-Yang, totaling eight phenomena when including sun-moon-stars-constellations; on earth it manifests as transformations of young and mature firm-gentle, also totaling eight phenomena when including water-fire-soil-stone. Their interlocking arrangement follows orderly patterns, like the 112 Yang lines on the left side of the Pre-Heaven diagram.

This scripture primarily discusses the operational principles of celestial Yin-Yang and ancient astronomical theories.

The interaction of Yin and Yang resembles the mating of male and female, or female and male creatures. When Qian (Yang) interacts with Kun (Yin), it forms the Fu hexagram; when Kun comes to interact with Qian, it creates the Gou hexagram. Qian and Kun represent the fundamental structure of heaven and earth formed by the division of Yin and Yang, while Kan and Li (water and fire) symbolize the dynamic forces generated through their interaction. Through the transformations of Kan and Li, Yin and Yang create heaven and earth, which in turn generate all things via Kan and Li.

The arrangement of the Later Heaven Bagua (established by King Wen of Zhou): The four trigrams Kan, Li, Zhen, and Dui occupy the cardinal directions, while the remaining four occupy the corners. This is because the North Star resides in the northwest, the celestial abode of heavenly deities, hence Qian occupies the northwest. Mount Kunlun lies in the southwest, dwelling place of earth deities, thus Kun occupies the southwest. Xun (wind) belongs to the southeast because winds blow from east to south moving all things. Gen (mountain) occupies the northeast as the most revered Mount Tai among the Five Sacred Mountains lies in this direction.

Regarding celestial forms: Heaven is round, earth is square. The southern heavens appear higher while the northern lower, resembling a tilted canopy. The Tang dynasty astronomer Yi Xing remarked that the Canopy Heaven theory (describing heaven as a canopy) could only explain half the phenomena, while the Celestial Sphere theory (viewing heaven as a globe) explained everything completely - Emperor Shun's jade astronomical instruments employed this spherical method.

Cai Yong recorded three celestial theories in his Astronomical Records:

1. Zhoubi Theory: Heaven resembles an inverted bowl with the North Star at its center, higher in the middle and sloping downward. The sun and moon revolve around it - daytime occurs when the sun is near, nighttime when distant. However, this theory contained many errors and was rejected by court historians. Alternatively, heaven was described as round like a canopy, earth square like a chessboard, with heaven rotating left while sun and moon move right but appear to set westward carried by heaven's motion. The rising sun becomes visible in Yang qi, while at sunset it enters Yin qi's darkness and disappears from view.

2. Xuan Ye Theory: Yu Xi explained "Xuan" means brightness and "Ye" darkness - this theory synthesized principles of light and dark. Xi Meng recorded that celestial bodies float in emptiness, their movements governed by qi. He also maintained heaven indeed has fixed form above, incorporating aspects of the Canopy Heaven theory. The Tang astronomer Li Chunfeng held similar views.

This scripture primarily examines several ancient cosmological theories about the structure of heaven and earth. The "Gaitian" (Canopy Heaven) theory posits that heaven and earth form a central high point with sloping sides, where the alternation of sun and moon creates day and night. The constantly visible northern celestial pole region is called the "upper circumference," while the often-hidden southern pole is termed the "middle circumference," with the celestial equator running horizontally as the "lower circumference."

Ge Hong proposed the "Huntian" (Celestial Sphere) theory, describing heaven as egg-shaped with earth resembling a yolk at its center. Heaven is vast while earth is small, with water existing both inside and outside this structure, floating and moving by means of Qi (vital energy). He Chengtian of the Song Dynasty suggested heaven forms a perfect circle with water occupying half its volume. The eastern sunrise location was called "Yang Valley," while the western sunset point was named "Xianchi." Zhuangzi's references to the Northern and Southern Seas demonstrate how water surrounds all directions, hence the term "Four Seas."

Within the Five Phases (Wood, Fire, Earth, Metal, Water), water is generated from metal (representing mountains and stones), as all rivers originate from mountains and flow to the sea. The sun, being Yang in nature, would theoretically dry up rivers when entering water at night, but seawater replenishes this balance—remaining undiminished during droughts and never overflowing in rainy seasons. Wang Fan described how the sun and moon first ascend to heaven before descending to earth, being above ground by day and below by night, reflecting ancient astronomical observation methods.

Han Dynasty scholars like Cai Yong and Zhang Heng all advocated the Huntian theory. Other theories included the "Xuantian" (Suspended Heaven) and "Xintian" (Manifest Heaven) concepts. Yao Xin of Wu state compared the human body to a spiritual insect that best reflects celestial patterns: the protruding chin mirrors heaven's lower southern part while the reclining head resembles heaven's elevated north, demonstrating humanity's status as the most spiritually endowed creature.

Ouyang Xiu argued that ancient shadow measurements primarily served to harmonize solar terms and assist agriculture, making excessive debates about celestial shapes unnecessary. Whether following Gaitian's narrowing southern hemisphere or Huntian's elevated northern sphere, these theoretical differences offered little practical value for moral cultivation. Nevertheless, scholars studying nature should prioritize truth-seeking above all.

The text concludes by describing the northwestern region as the highest point supporting heaven's apex, with Yu Xi affirming that heaven indeed remains eternally stable in its lofty position. This passage reflects ancient China's multifaceted understanding of cosmic structure, blending astronomical observation with philosophical contemplation.

This passage elucidates the distribution patterns of celestial and terrestrial Yin-Yang forces and their influence on natural phenomena. It begins by interpreting the numerical arrangement in the Luoshu diagram where "nine crowns the head and one treads below": the number one at the bottom represents the Kan trigram (Water), symbolizing the inception of celestial phenomena, while the number nine at the top signifies the Qian trigram (Metal), marking their completion. Water’s nature is soft yet dynamic, Metal’s is firm yet quiescent—mirroring how the North Star remains eternally fixed, forming the stable framework of celestial motion.

The text then describes the distinctive distribution of Yin-Yang forces: celestial Yang energy concentrates in the south and Yin in the north, while terrestrial Yin prevails in the south and Yang in the north. This configuration results in scorching southern heat and frigid northern cold, where southern substances dissolve and northern ones solidify, creating climatic extremes inhospitable to life. Using the "Innate Circular Diagram" and "Innate Square Diagram" of trigram arrangements, it illustrates how the celestial map positions Qian (Heaven) in the south and Kun (Earth) in the north, whereas the terrestrial map places Qian in the northwest and Kun in the southeast.

Further analysis examines specific phenomena: the sun reveals itself in the south and conceals in the north. Though the south belongs to terrestrial Yin, it brims with Yang energy, causing water to melt; though the north pertains to terrestrial Yang, Yin suppresses Yang there, forming towering mountains. Water’s pliant Yin nature serves Yang’s purposes, while mountains’ rigid Yang essence submits to Yin’s dominion. The passage concludes by emphasizing that only through the harmonious interplay of celestial and terrestrial Yin-Yang, balancing cold and heat, can all beings flourish. Quoting Zhu Xi’s recounting of Hu Anding’s words, it depicts the cosmos’ physical form: the vault of heaven tilts like a pestle, with the South Pole submerged 36 degrees below the horizon and the North Pole elevated 36 degrees above. The celestial sphere traverses over 900,000 li in a single day-night cycle—yet within a single human breath, heaven and earth have already journeyed vast distances.

This scripture primarily explores ancient astronomical calculations concerning celestial movements and the distances between heaven and earth. It records that during one day and night, a person breathes approximately 13,600 times, while celestial bodies traverse over 900,000 li in the same period. Ancient alchemical texts (Daoist cultivation scriptures) note that humans complete 13,500 breaths daily, with 1,125 breaths constituting one shichen (two-hour period) — a rounded calculation for convenience.

Zheng Xuan, in his commentary on the Kaolingyao, proposed that the cosmos originally lacked fixed form, and humans comprehend celestial bodies by observing stellar movements. Stars rotate east to west, returning to their original positions after 365¼ days. The sun moves in the opposite direction, also requiring 365¼ days to realign with its corresponding stellar position. Ancient scholars termed the sun's daily travel distance as "one degree," dividing the entire celestial circumference (ecliptic) into 365¼ degrees.

The scripture details celestial dimensions: the heaven's circumference measures approximately 1,071,000 li. Using the "circumference-three, diameter-one" principle (approximating pi as 3), its diameter calculates to about 357,000 li — representing the orbital diameter of the Twenty-Eight Lunar Mansions. Beyond these constellations, each cardinal direction extends an additional 15,000 li, termed the "Four Boundaries" (cosmic limits), yielding a total cosmic diameter of roughly 387,000 li. The central point between heaven and earth lies equidistant (193,500 li) from both upper and lower boundaries, with the earth positioned precisely at this center.

Additional records state the earth's thickness measures approximately 30,000 li. Wang Fan's commentary on the Shangshu notes: the visible celestial dome comprises 182.5 degrees above ground, mirrored by an equal measure below. The North Star rises 36 degrees above the horizon, while Mount Song (the Central Peak) aligns with the celestial zenith. Fifty-five degrees south corresponds to the sky above Mount Song, with an additional 12 degrees marking the summer solstice solar path (ecliptic), and a further 24 degrees indicating the equinoctial solar orbit.

These computations reflect ancient Chinese astronomers' unique methodology of deriving cosmic scales through respiratory rhythms and stellar motions, embodying the "correspondence between heaven and humanity" cosmology. Key concepts like "celestial degrees" and "Four Boundaries" represent foundational terminology in classical astronomy.

This scripture primarily elucidates ancient astronomical understanding of celestial motion patterns. The text states that during the winter solstice, the sun's path shifts 24 degrees southward, positioned 31 degrees above the horizon; at summer solstice it shifts northward, 67 degrees from the North Pole. During equinoxes, it's 91 degrees from the North Pole, extending to 115 degrees at winter solstice. The celestial north and south poles serve as the rotational axis around which the sun, moon, and stars revolve along this tilted axis.

Zhang's (possibly referring to Zhang Heng) Hun Tian theory proposes: While the celestial sphere rotates around earth, our planet remains horizontally fixed at the cosmic center, with the heavens tilted higher in the south and lower in the north. The celestial sphere divides into northern and southern hemispheres - the North Pole rises 36 degrees above ground while the South Pole sinks 36 degrees below. Ancient observers noted that stars within 72 degrees of the North Pole remain perpetually visible (called "upper circumference"), while those within 72 degrees of the South Pole stay permanently hidden ("lower circumference"). This fixed visibility pattern corresponds to the 144 counting rods (calculation units) in the Kun hexagram of the Yijing (Book of Changes), while the 216-degree cyclical motion east-west aligns with the Qian hexagram's 360 rods.

Regarding earthly motion, Zhang posited that while the ground appears static, it actually floats vertically with the rising and falling of Yin-Yang energies. When Yang Qi ascends, earth descends (creating void); when Yang Qi descends, earth rises (creating fullness) - this movement generates seasonal temperature variations. The Kaolingyao records earth's thickness as 30,000 li: during spring equinox it occupies the celestial center, gradually descending until summer solstice (15,000 li below), returning to center at autumn equinox before rising 15,000 li by winter solstice. This cyclical undulation drives seasonal transitions.

(Note: "Counting rods" refer to ancient yarrow stalk calculation units in divination, with Yijing using their numerology to symbolize cosmic patterns; "Hun Tian theory" was a major Han dynasty cosmological model envisioning heavens as eggshell encircling yolk-like earth)

This passage examines ancient astronomical theories concerning celestial movements. The ancients believed the earth moved vertically and horizontally through the cosmos—descending during the winter solstice and ascending during the summer solstice, with an amplitude of approximately thirty thousand li. During the first lunar month, the sun was thought to be eighty thousand li from the celestial zenith and one hundred thirteen thousand five hundred li from the earth's surface. At summer solstice, the sun rose to align with the celestial dome, while at winter solstice it descended to eighty thousand li above the earth.

The text cites the Kaolingyao records: The Twenty-Eight Lunar Mansions and other stars all rotated leftward along the celestial dome, completing one full revolution daily and 365¼ revolutions annually. Meanwhile, the sun moved rightward by one degree each day, and the moon advanced 13⁷⁄₁₉ degrees daily—all precisely calculated figures.

Zhu Xi (Master Zhu) offered a vivid analogy: Imagine a small bowl floating in a large basin. If the bowl drifts three inches eastward (symbolizing the earth's thirty-thousand-li movement), it simultaneously recedes three inches from the west. He proposed that seasonal variations in daylight duration resulted not from the sun's motion but from the earth's cyclical wanderings. Though counterintuitive, calendrical experts found these calculations consistent with celestial observations.

(Note: This reflects the ancient Huntian cosmological model, which envisioned the earth suspended in patterned motion through space. While differing from modern scientific understanding, it demonstrates the ancients' mathematical ingenuity in modeling astronomical phenomena through observation.)

This passage discusses ancient astronomical observations regarding the cyclical movements of the earth and celestial bodies. Ancient scholars believed both the earth and stars underwent periodic "four wanderings" (siyou), referring to their relative positional changes through the four seasons, manifested as movements and ascension/descent in four directions.

In spring, the earth and stars move westward. At the spring equinox, they reach their westernmost point, when the ascension/descent movement stands precisely at the central position. They gradually shift eastward thereafter, returning to center by late spring. Summer begins with northward movement, reaching the northern extreme at summer solstice when the ascension/descent position is lowest, before recentering by summer's end. Autumn brings eastward movement, with the easternmost point attained at autumn equinox (ascension/descent at center), then returning to neutral by autumn's conclusion. Winter features southward movement, achieving the southern apex at winter solstice (ascension/descent at highest position), before recentering at season's end. This constitutes the fundamental principle of earth and stars' "four wanderings."

Using sundials (tugui, ancient shadow-measuring instruments), ancient observers discovered the stars' vertical range of movement with the earth never exceeded 30,000 li (Chinese miles). Half this distance—15,000 li—corresponded precisely to the sundial's 1.5 chi (Chinese feet) gradations. The conversion ratios were: 1 chi of shadow difference equaled 10,000 li on earth, 5 cun (inches) equaled 5,000 li, and 1 fen (0.1 cun) equaled 100 li. All shadow length variations followed the "one cun" principle.

Some skeptics dismissed the "four wanderings" theory as fanciful, yet eminent Confucians like Zhu Xi endorsed it. The Rites of Zhou records sundial measurement methods: short shadows in southern measurements indicated heat; long northern shadows signified cold; eastern measurements suggested windy conditions; western measurements implied cloudiness. Zheng Xuan's commentary explains: "Jingxi" meant taking measurements when the sun was west of meridian, while "Jingzhao" referred to measurements taken before solar noon. Zhu Xi considered Zheng's interpretation essentially correct despite minor inversions—"Jingxi" actually meant measuring before noon, and "Jingzhao" after noon. Eastern regions naturally tended to be windier, just as coastal areas predictably experience strong seasonal winds.

This account reveals how ancient scholars interpreted cosmic patterns through shadow observations, systematically correlating astronomical data with climatic characteristics.

This passage primarily explains ancient methods for determining geographical centers by observing natural phenomena like wind direction and solar shadows, along with the evolution of related astronomical measurement techniques.

In spring, easterly winds prevail, while summer brings southerly winds. In open areas unobstructed by mountains, seasonal winds blow consistently from their respective directions. Wind patterns correlate with the waxing and waning of Yang Qi (vital energy): morning winds arise with ascending Yang Qi, peak at noon, gradually weaken in the afternoon, and cease by evening. The northwest region accumulates heavy Yin Qi (dark energy) not just due to mountainous barriers, but because Yang Qi weakens upon reaching there. When the sun sets in the west, the northwest essentially enters nighttime prematurely, resulting in shorter daylight hours. Ancient descriptions like "Shu region sees little sun" and "Yue territory receives abundant snow," or the term "sky leakage," poetically capture these light-deprived areas. Such natural phenomena reveal the operating principles of Heaven and Earth.

Tang dynasty scholar Jia Gongyan recorded that Duke of Zhou (founding statesman of the Zhou dynasty), when constructing Luoyang, established five marker poles to locate Earth's center: a central pole at Yangcheng in Yingchuan (modern Dengfeng, Henan) for solar measurements, with additional poles placed a thousand li north, south, east, and west. Shadow lengths determined the central point. Zhu Xi later noted that people had forgotten the proper use of the tugui (jade sundial), with even Zheng Xuan (Eastern Han Confucian scholar) misunderstanding its operation. The authentic tugui was a jade ruler measuring 1.5 chi (about 50cm) - at summer solstice, a vertical gnomon's shadow matching this length marked the geographical center. By winter solstice, shadows would extend over 1.3 zhang (about 4 meters).

Historical determinations of Earth's center shifted: the Han dynasty recognized Yangcheng, while the Song dynasty adopted Yuetai (near modern Kaifeng, Henan). During Tang Kaiyuan's 12th year (724 CE), nationwide measurements revealed Junyi Yuetai as the precise north-south midpoint. When the Later Zhou established their capital at Bianjing, they erected a sundial at Yuetai to determine solar terms. Lu Xiangshan (Southern Song philosopher) added that ancients combined water clocks with floating indicators to mark hours, correlating the sun's path with day/night duration. Using tugui for solar measurements and lodestones for orientation, they established the twenty-four directional system. After three calibrations of the water clock's markers both south and north of Yuetai, they finalized the standardized timekeeping system.

This passage explores the relationship between celestial and terrestrial movements and the determination of directions. Ancient scholars believed that heaven enveloped the earth, with the earth positioned at its center (as proposed by Master Hengqu, Zhang Zai). Heaven was described as a vast spherical body, higher in the north and lower in the south, while the earth lay flat within it. Shao Yong (Master Shao) stated that heaven covers the earth, and the earth supports heaven; in truth, heaven contains earth, and earth contains heaven, though humans standing on the ground cannot perceive this.

Regarding celestial motion, ancient observers noted that while heaven appeared motionless when viewed from within, it actually rotated leftward, with the stars collectively revolving around the North Pole. Using the pre-heaven Bagua (Eight Trigrams) diagram, the sixteen hexagrams above Lin (临) and Shi (师) represent the cyclical patterns of heaven (the temporal system of yuan-hui-yun-shi), while the sixteen hexagrams below Tongren (同人) and Dun (遁) correspond to earthly time divisions (year, month, day, and hour).

On earth, directions remain fixed, but celestial phenomena are in constant motion. Only when the celestial Firebird constellation (one of the twenty-eight lunar mansions) aligns with the due south (午 position) do the movements of heaven and earth achieve perfect correspondence. Zhu Xi (Master Zhu) further explained that the celestial sphere is divided into twelve periods (会), with each month corresponding to different stellar positions—for instance, the eleventh month aligns with Xingji (星纪), and the twelfth with Xuanxiao (玄枵). From an earthly perspective, when a person stands facing south, their front, back, left, and right also align with the fixed twelve earthly branches (辰).

The celestial circle was precisely divided into 365¼ degrees, with the twenty-eight lunar mansions serving as coordinates to mark celestial positions. Heaven completes one full rotation around the earth in a day and night, but in reality, it advances slightly more than a degree each day—this discrepancy explains the precession of the equinoxes caused by the movements of the sun, moon, and five planets. When ancient scholars used magnetic needles (early compasses) to determine directions, they noticed the needle did not point exactly due south but deviated between Bing (south by east) and Wu (due south). This phenomenon, observed since the Zhou dynasty, became a crucial basis for studying the principles of Yin-Yang.

The stars follow the celestial sphere in its rotation around the earth, yet the sun's movement is most regular, completing a full cycle each day with neither haste nor delay. Other celestial bodies vary in their speeds. These stars are neither fixed to the heavenly canopy nor propelled by external forces; rather, they naturally emit light and follow their ordained paths due to the abundance of their own vital essence (Qi).

The Huangdi Neijing commentary explains: The celestial vault appears to dip in the northwest, while the earth seems sunken in the southeast. Hence, the southeast abounds with waters, and the northwest with mountains. The Hetu Kuodixiang records: The northwest is the Celestial Gate (Tianmen, entrance to the heavens), and the southeast is the Earthly Door (Dihu, exit of the earth). The Celestial Gate lies at the highest point, the Earthly Door at the lowest, and the celestial phenomena illuminate the earth from above, spanning ten thousand miles. Another view holds: The southern region bathed in sunlight extends fifteen thousand miles, and if measured from the earth's center, the distances between north, south, east, and west each span thirty thousand miles.

Ancient scholars believed the mountains and rivers of the Central Plains all originated in the northwest, so their records of these features always proceeded from northwest to southeast. The land’s mountains and rivers resemble the veins of the human body—sometimes appearing disconnected yet resonating across distances. As the ancients said: Have the waters of rivers and seas ever severed the earth’s pulse? Scholar Cai Yuanding observed: The main mountain ranges north of the Yellow River all stem from the Huanwu and Lanxian ranges in the Daibei region. These towering ridges split into two branches—the western waters flow into the upper reaches of the West River near Longmen, while the eastern waters form the Sanggan River, passing through Youzhou and Jizhou before reaching the sea. The western branch extends into the Kongkou and Dayue mountains; the central branch encircles Jinyang (modern Taiyuan); further east lies the Taihang Mountains; and the easternmost branch is Mount Heng, belonging to the northern range. The southern range comprises the mountain systems south of the Yangtze and Han rivers: The Min Mountains stretch northward as Mount Heng, ending west of Dongting Lake, while the southern branch crosses the Gui Ridge, passes north through Yuanzhou and Junzhou, and reaches Fushanyuan in De'an County (near modern Lushan). Some also argue that present-day Mount Lu in Jiangzhou lies between two branches, with the Xiang River interrupting here—Mount Heng stands southeast of the Xiang, and Fushanyuan northeast, their origins all verifiable. Zheng Xuan classified Mount Qian and Mount Qi as the True Yin range (traversed by the Yellow and Ji rivers), Mount Xiqing as the Northern Yin range (traversed by the Yi, Luo, Huai, and Wei rivers), Mount Bozhong as the Lesser Yang range (traversed by the Han River), and Mount Min as the True Yang range (traversed by the Yangtze).

The Tianyuan Fawei text primarily discusses two aspects of geographical knowledge: the historical changes of ancient rivers, and the correspondence between China's mountain-water systems and celestial divisions.

Regarding river transformations, it records that the Yellow River had two sources in the Western Regions—one originating from the Congling Mountains (modern Pamir Plateau) and another from Khotan (modern Hetian, Xinjiang). These two tributaries converged and flowed eastward into Puchang Sea (also called Salt Marsh, modern Lop Nur), located over three hundred li from the Yumen and Yang Passes. The water volume here remained constant throughout winter and summer, then submerged underground before reemerging from the Jishi Mountains (modern Qinghai). Scholar Cheng (possibly Song dynasty scholar Cheng Dachang) proposed that before the Yellow River's nine distributaries were submerged by seawater, about five hundred li northeast from what is now the coastline, the river split into nine branches emptying into the ocean, marked by the Jieshi Mountain (modern Changli, Hebei). However, continuous heavy rains and northeastern winds caused seawater to inundate the land, submerging both the nine distributaries and Jieshi Mountain. Later scholars searching for traces of the nine rivers only looked inland without verifying through Jieshi Mountain's original position, resulting in conflicting theories without consensus.

The second part explains celestial-terrestrial correspondences. The Tang dynasty Faxiang Zhi records how terrestrial mountains and rivers mirror celestial star divisions. Northern mountain ranges begin from Sanwei Mountain (modern Gansu) and Jishi Mountain, extending along the northern side of Zhongnan Mountains (Qinling range) to the Korean Peninsula—called the "Northern Boundary" (Beijie), serving as natural barriers against northern nomadic tribes. Southern ranges start from Min Mountain and Bozhong Mountain (modern Shaanxi), running along Qinling's southern side to Zhejiang and Fujian—called the "Southern Boundary" (Nanjie), acting as buffers against southern ethnic groups. The Yellow River's source, termed "Northern River" (Beihe), stretches from the Northern Boundary's starting point to the northern foothills of Mount Hua, where it intersects with subterranean water systems before branching eastward, harmonizing with the Jing, Wei, and Ji Rivers (among the ancient Four Major Rivers). The Yangtze's source, called "Southern River" (Nanhe), extends from the Southern Boundary's origin to Mount Hua's southwestern side, meeting subterranean currents before branching eastward at Mount Jing (modern Hubei), resonating with the Han and Huai Rivers. By observing these two great rivers' connections with the Milky Way's course, one can determine regional astrological correspondences.

The conclusion states that these Northern and Southern Boundaries represent heaven's demarcation of China's territorial limits, while the two great rivers crisscross these mountain ranges. Within this land, civilization and martial prowess coexist amid abundant resources that nurture the people, forging a nation governed by ruler-subject and father-son relationships, benevolence-righteousness, and ritual-music traditions. In the cosmos, the greatest is heaven, the most substantial is earth, and the most abundant is water—whose essence ascends to form the Cloudy Han (Milky Way) and descends as rivers.

The Tianyuan Fawei scripture primarily discusses the correspondences between heaven-earth-mountains-rivers and celestial phenomena, along with the connections between ancient emperors and the Five Phases (Wuxing) directions.

The text states that the forms of mountains and rivers as well as the distribution of stars are all shaped by the same primordial Qi (cosmic source energy). By observing the two major mountain ranges (northern and southern "boundaries"), one can understand the veins of the land; by tracking the seasonal movements of the Big Dipper (four cardinal directions), one comprehends celestial patterns. Ancient sages aligned Han Dynasty commanderies with specific stellar mansions as clearly as reading one's palm.

Specifically, the northern mountain range corresponds to the "Ximu" stellar division, while the southern range matches the "Xingji" division. The "Chunshou" constellation, for instance, corresponds to the Qin-Long region where the north-south mountain ranges originate. A ruler must gather the refined Qi (vital energy) of the Central Plains and master the cosmic directional principles represented by the Five Emperors to properly govern.

The text elaborates the heaven-earth correspondences: the Milky Way stretching from Kun (southwest) to Gen (northeast) represents earthly order, while the Big Dipper extending from Qian (northwest) to Xun (southeast) symbolizes celestial law. The Five Emperors correspond to Five Phases directions: Shaohao (Metal Virtue) in the west, Zhuanxu (Water Virtue) in the north, Fuxi (Wood Virtue) in the east, Shennong (Fire Virtue) in the south, and Huangdi (Earth Virtue) at the center.

Each celestial emperor governs specific stellar divisions and geographical regions—Shaohao presides over Jianglou constellation, Zhuanxu over Zouzi, etc. The Dipper's handle points south to Chunwei constellation (coastal regions), while its bowl aligns north with Zouzi (Central Plains). Other constellations flanking the Milky Way similarly correspond to terrestrial domains.

Finally, the text describes four major mountain ranges corresponding to the twenty-eight lunar mansions. Eastern mountains like Qian and Qi align with eastern mansions governed by Jupiter (Wood Star); northern ranges like Xicheng and Wangwu match northern mansions ruled by Mercury (Water Star). These systematic correspondences form the ancient cosmological framework of heaven-human unity.

This passage describes the ancient Chinese system of geographical divisions that correlates terrestrial regions with celestial constellations. The main content can be divided into several sections:

First, it explains the correspondence between the Five Sacred Mountains and their governing stars: Mount Hua in the west is associated with Venus (Taibai Jinxing), Mount Heng in the south with Mars (Yinghuo), and Mount Song (the Central Peak) with Saturn (Zhenxing). Each of these sacred mountains is governed by celestial deities corresponding to their respective stars.

Next, it outlines the geographical layout of the realm: The Hongnong region (modern-day Lingbao, Henan) serves as the boundary dividing the land into eastern and western sections. The western territory comprises the Qin-Liang region, while the northern mountain bends correspond to the Jin dynasty's domain, and the southern bends to Ba-Shu. In the eastern Sanchuan region stands the Central Peak (Mount Song), bounded by Waifang Mountain to the west, Dapi Mountain to the north, and the Huai River to the south—an area renowned for its flourishing culture.

The text then introduces prosperous coastal trading regions: From Xíng-Zhào in the north to Jing-Chu in the south, the area eastward to Mount Dai (Tai Shan) forms the "Three Qi" region. North of Jieshi Mountain lies Northern Yan, while the lower reaches of the Southern River north to Mount Dai encompass Zou-Lu, and beyond the Yangtze-Huai region lies Wu-Yue.

Finally, it discusses the cosmic correspondence between heaven and earth, quoting Zhang Heng (Zhang Pingzi): "Heaven has nine positions, earth has nine domains," illustrating their mirrored forms. It also mentions methods for measuring celestial distances: The diameter of the "Eight Extremities" (four poles of heaven and earth) spans approximately 200 million li. Using the Pythagorean theorem to measure solar shadows, the text notes that for every thousand li of earthly movement, the shadow shifts by one inch. These numerical relationships reflect ancient understandings of cosmic correlations.

This passage explores the boundless expanse of the cosmos and the development of human civilization. The universe (宇 denoting space, 宙 denoting time) has no discernible limits—its profundity is infinite and ultimately unfathomable. The author attempts to comprehend the structure of heaven and earth by examining the territorial boundaries during the era of the Three Sovereigns and Five Emperors, citing Confucius' description of ancient geography: extending north to Youling (near present-day Beijing), south to Jiaozhi (northern Vietnam), west to the Flowing Sands (northwestern deserts), and east to Panmu (the immortal mountains of the Eastern Sea).

Where the refined Qi (vital energy) of heaven and earth converges, auspicious signs manifest in the Yellow River, giving rise to the legendary River Chart and Luo Writing—celestial diagrams believed to be bestowed by heaven. Among humanity, the most exceptional individuals became sages, such as the Duke of Zhou and Confucius, who carried forward the legacy of ancient sages like Fuxi, laying the foundations of Chinese ritual and musical civilization. Talented individuals emerged across the land: the region of Zou-Lu (around Qufu in Shandong) produced refined Confucian scholars, Yan-Zhao (Hebei region) bred heroic figures, and both sides of the Taihang Mountains yielded generals and statesmen, all collectively sustaining the flourishing of Huaxia civilization.

Yu the Great inherited the golden age of Yao and Shun, governing the Nine Provinces and demarcating over nine million qing of arable land while channeling eight thousand li of waterways. Across the realm, there were more than five thousand famous mountains, over four hundred copper-producing peaks, and three thousand iron-rich mountains. The people lived in harmony—men plowed the fields while women wove cloth—resulting in abundant state finances. Government granaries held thirty years' worth of reserves, and households stored nine years' worth of grain. By the zenith of the Zhou dynasty, the population had reached over twenty million.

The text also references Zhu Xi's view that the River Chart records Mount Kunlun as the earthly center, supported beneath by eight colossal pillars, with the caverns of famed mountains and great rivers interconnected. The Commentary on the Water Classic states that Kunlun lies fifty thousand li from the Central Plains, its massive form towering eighty thousand ren (an ancient unit of length), crowned with nine-tiered citadels and nine jade wells—serving as the celestial emperor's earthly capital. These descriptions reveal the ancients' grand imagination of cosmic structure.

When someone inquired about the geographical location of Tianzhu (ancient India), Zhu Xi replied: China is twenty thousand li from Khotan (modern-day Hetian in Xinjiang), and it’s impossible for Khotan to be another thirty thousand li from the Kunlun Mountains. According to the Wenchang Miscellaneous Records, envoys from Khotan once reported during their tribute missions that their country lay about thirteen hundred li west of the Kunlun Mountains. Present-day China is located southeast of Kunlun, while the various states of Tianzhu lie directly south of it. The Yellow River flows from the southeastern side of Kunlun into China. From this perspective, the Kunlun Mountains should be situated in the southwest.

Buddhist scriptures (Zhuqian Texts) record that Mount Anu is none other than the Kunlun Mountains. At its summit lies the Great Anu Pool, whose waters divide and flow in all directions: the branch entering China becomes the Yellow River, eventually emptying into the Eastern Sea. The other three directions feed into the Southern, Western, and Northern Seas, giving rise to rivers like the Weak Water and Black Water. The earth’s shape resembles a steamed bun, with Kunlun as its raised peak. China’s terrain is round and balanced, so the people and things born here are likewise upright and complete, having received the harmonious Qi (vital energy) of heaven and earth. Other lands, with their skewed and fragmented shapes, encircle the periphery, deprived of heaven and earth’s proper Qi, and thus most beings there lack completeness. This reflects the ancient "Canopy Heaven" theory, which Zhang Zai (Master Hengqu) also endorsed.

Ancient geographical records state: The northwest abounds in mountains, with Kunlun as the ancestor of all ranges. Its fundamental ridges span the world, weaving through the Five Sacred Peaks (Mount Tai, Mount Hua, etc.) and the Three Paths Mountains (legendary gates to the underworld). It also notes that the Yellow River originates from Kunlun, where the terrain is highest. To the north lies open desert without natural barriers, making the river prone to bursting its banks and flooding wildly. Yu the Great tamed these raging waves by dredging nine channels.

Additionally, it is said: Mount Song is not the center of heaven but the center of earth. The ecliptic and celestial equator both lie north of Mount Song. The North and South Celestial Poles are the pivots of heavenly motion—only these remain still, like the central axle of a millstone. This is the true center of heaven. Shao Yong (Master Shao) remarked: The foundations of heaven and earth both arise from the center. Where is heaven’s center? At the North Star (Polaris). Where is earth’s center? At Mount Song. Precisely because heaven centers on Polaris, we can establish calendars and calculate solar terms; precisely because earth centers on Mount Song, we can fix directions and measure distances. The meridian line is the central axis of heaven and earth—at the winter solstice, when Yang energy first stirs, midnight marks the Zi hour. Thus, the Qian hexagram begins at the Kan position and ends at the Li position, embodying the principle of the South Celestial Pole.

The North Star (also known as the Celestial Pivot) remains the unmoving hub of the heavens, serving as the axis of the celestial sphere. At the summer solstice when Yin energy begins to germinate, the sun reaches its zenith at high noon. Thus in the Book of Changes, the Kun hexagram (symbolizing Earth) originates from the Li hexagram (symbolizing Fire) and culminates in the Kan hexagram (symbolizing Water). This celestial mechanism operates with the same precision as the ecliptic (the sun's path) and celestial equator intersecting north of Mount Song.

The central pivot of cosmic movement remains eternally constant. Ancient sages calculated the grand cycles of celestial motion by observing the Jade Balance (an ancient astronomical instrument), using these cardinal points to predict future transformations—all derived from this fundamental principle. When asked whether my "Chapter of Mysterious Unity" could fully reveal the patterns of heaven and earth, I replied: "Impossible. For celestial phenomena we have the records of the Imperial Astronomers, for geography we have the Finger-Pointing Atlas, for astrological correspondences we have the research of Monk Yixing from the Tang dynasty, and for water systems we have Li Daoyuan's Commentary on the Water Classic. Yet these merely describe existing phenomena without touching ultimate truth."

As Yang Xiong's Canon of Supreme Mystery states: "To follow the mysterious movement of the celestial bodies is to emulate the endless Way of Heaven." The profound meaning of this mysterious realm truly transcends complete verbal expression.