Zongsheng Talks (Zengzi)

周易之書，文王所作；易卦之象，伏羲所制。文王演之以盡其變，是為周易，故卦象一而用二，卦名同而用殊。以伏羲初制為先天象，文王復演為後天象，以此分別，體用斯明。

The book of Zhou Yi was composed by King Wen; the images of the hexagrams were created by Fuxi. King Wen elaborated upon Fuxi's hexagrams, exhausting their transformations, thus forming the Zhou Yi. Therefore, the images of the hexagrams are only one set, yet their functions are divided into two layers; the names of the hexagrams are the same, yet their uses differ. The hexagrams originally created by Fuxi are considered the Earlier Heaven images, while those re-examined and elaborated by King Wen are regarded as the Later Heaven images. By distinguishing them in this way, the relationship between their essence and function becomes clear.

然夫子刪訂六經，獨宗周易，而不及文王以前者，文王之作，足賅各易也。文王之易，雖屬後天，而先天存乎其中。人之生也，神存形中，言形而神在，以神之德，體物不遺也。先天之象亦然，先天以後天用，後天以先天神，先後並行，神用無極。故曰「神無方，易無體」，以體不見，由其而用見也。

However, the Master edited the Six Classics, and alone revered the Zhou Yi, without involving the Yi texts prior to King Wen, because King Wen's work was already sufficient to encompass all other schools of Yi. Although King Wen's Yi belongs to the Later Heaven, the Earlier Heaven exists within it. Just as when a person is alive, the spirit resides within the body; when speaking of the body, the spirit is within it, because the spirit's virtue pervades all things without omission. The images of the Earlier Heaven are also like this: the Earlier Heaven relies on the Later Heaven to manifest its function, and the Later Heaven relies on the Earlier Heaven to reveal its spirit. The two proceed together without contradiction, and the mysterious function has no end. Therefore, the Great Treatise of the Upper Transmission says, "The spirit has no fixed form, and the Yi has no independent form," precisely because the essence is invisible, so it must be revealed through its manifested function.

然體不可見，因而忘之，不可也；先天之象，不用可也，因而蔑之，不可也。故言後天必及先天，原始要終，易之道固如是；推來溯往，易之用亦當然。明乎先天，則知後天所出；明乎後天，則知先天所存。氣數不同，名類異致，雖猶木本與枝、水源與流，一脈所傳，而在既變之後，形神各別，理氣殊途，有一而不一、同而未同者在也。

Although this is the case, if we cannot see the essence, we should not forget it; although the images of the Earlier Heaven may be temporarily set aside, it is also wrong to therefore disregard them. Therefore, when discussing the Later Heaven, we must inevitably involve the Earlier Heaven, investigating the beginning and concluding at the end. The principles of the Book of Changes are inherently like this; inferring from the future and tracing back to the past, the application of the Book of Changes should also be like this. If we understand the Earlier Heaven, we will know where the Later Heaven comes from; if we understand the Later Heaven, we will know where the Earlier Heaven resides. The two differ in terms of qi and numbers, and in their names and categories. Although they are like the trunk and branches, the source of water and its tributaries, originating from the same root and passed down in succession, after transformation, form and spirit become separate, principles and qi take different paths, thus resulting in a situation where they are one yet not one, similar yet not entirely the same.

故言文王之易，必溯以前之易；習文王之卦，必本以前之卦。卦同而異，以用不同；易異而同，以體無異。故雖有同異，而不得不求其合也。合則通，通則神；不合不通，滯於物而失其神，將何以致易之用哉？故學者必將先後天二者氣與數之分，明晰無遺，再將二者之合，通貫無滯，庶可以因文王之作，探伏羲之制，即可由周易包括以前之易也。請將先後天卦象之同異者略述之。

Therefore, to discuss the Yi of King Wen, one must trace back to the earlier Yi; to study the hexagrams of King Wen, one must take the earlier hexagrams as the foundation. Although the forms of the hexagrams are the same, their meanings differ because of different applications; although the books of Yi differ, their essence is the same because their fundamental nature is not different. Therefore, although there are similarities and differences, one must strive to find a way to integrate them. Only when they are integrated can one understand clearly, and only when one understands clearly can one grasp the profound; without integration, one cannot understand clearly, and one remains stuck in specific things, losing the profound essence, and then how can one make use of the Yi? Therefore, those who study the Yi must first clearly understand the differences between the Earlier Heaven and Later Heaven in terms of qi and numbers, and then integrate their convergence without any obstruction, only then can one use King Wen's work to explore Fuxi's system, and also be able to use the Zhou Yi to encompass all previous forms of Yi. Below is a brief explanation of the similarities and differences between the Earlier Heaven and Later Heaven hexagrams.

先天八卦方位次序，與後天異。先天乾坤上下，離坎東西；震居坤左，巽在乾右；艮連坎坤，兌接離乾。此為相對，方位卦象皆相對也。乾陽坤陰，離陰坎陽，震艮皆陽，巽兌同陰；陰下陽上，陰上陽下；一陽與一陰對，二陽與二陰對，無相失也。

The arrangement and order of the Earlier Heaven Trigrams differ from the Later Heaven. In the Earlier Heaven, Qian is at the top and Kun at the bottom, Li is in the east and Kan in the west; Zhen is placed to the left of Kun, and Xun to the right of Qian; Gen is connected with Kan and Kun, while Dui is connected with Li and Qian. This forms a structure where each element is opposite to another. The positions and trigrams are paired oppositely throughout. Qian belongs to Yang, and Kun to Yin. Li has Yang outside and Yin inside, while Kan has Yin outside and Yang inside. Zhen and Gen both belong to Yang, while Xun and Dui both belong to Yin. When Yin is below, Yang is above; when Yin is above, Yang is below. A trigram containing one Yang is opposite to one containing one Yin, and a trigram with two Yangs is opposite to one with two Yins. There is no error in the pairing.

故其數為乾一、兌二、離三、震四，此左之行卦；巽五、坎六、艮七、坤八，此右之下行卦。而其本數，則與河圖同。其式為左右兩行，左則自下數，右則自上數：左為震一、離三、兌七、乾九，右為巽四、坎二、艮八、坤六。

Therefore, the sequence of the trigrams in the Earlier Heaven arrangement is Qian one, Dui two, Li three, Zhen four, which are the trigrams on the left row moving upward; Xun five, Kan six, Gen seven, Kun eight, which are the trigrams on the right row moving downward. As for their original numbers, they correspond with the Yellow River Chart. The diagram is divided into two rows, left and right. On the left, the numbers are counted from bottom to top; on the right, from top to bottom: the left row is Zhen one, Li three, Dui seven, Qian nine; the right row is Xun four, Kan two, Gen eight, Kun six. One should be careful to distinguish between "sequence numbers" and "original numbers": Qian one to Kun eight represent the order of arrangement, while Zhen one to Kun six correspond to the qi numbers assigned by the Yellow River Chart. The left row moves upward from bottom to top, symbolizing the generation of yang qi from the bottom upward, layer by layer; the right row moves downward from top to bottom, symbolizing the descent of yin qi from the top downward, layer by layer. The alternating ascent and descent of the two rows establish the dual opposition structure of the Earlier Heaven arrangement.

九 乾　　巽 四；七 兌　　坎 二；五；三 離　　艮 八；一 震　　坤 六

This is the diagram of the Earlier Heaven Trigrams, divided into five layers, with the trigrams arranged facing each other on the left and right sides. The top layer has Heaven (Qian) with the number nine on the left and Wind (Xun) with the number four on the right. The second layer has Lake (Dui) with the number seven on the left and Water (Kan) with the number two on the right. In the center is the number five alone. The fourth layer has Fire (Li) with the number three on the left and Mountain (Gen) with the number eight on the right. The bottom layer has Thunder (Zhen) with the number one on the left and Earth (Kun) with the number six on the right. The odd numbers on the left side, one, three, seven, and nine, are arranged from bottom to top as yang numbers. The even numbers on the right side, four, two, eight, and six, are arranged from top to bottom as yin numbers. The central number five represents the earth number and is not included in the Eight Trigrams but is hidden at the center of the diagram.

此即先天卦數，合河圖者也。以乾九坤六，為乾坤大用；左為陽數，一三七九，順行而上；右為陰數，四二八六，逆行而下；五在中央。以一合六為水，三合八為木，七合二為火，九合四為金，五為土，以成交互之則。一與四、三與二、七與八、九與六，皆成五，即中央所得之數也。故卦八而數九，中數暗藏，明卦之體不見，而寓於用也。

This is the numerical sequence of the Earlier Heaven hexagrams, in harmony with the Yellow River Chart. The great function of the hexagrams Qian and Kun is represented by the numbers nine and six respectively. On the left side are the yang numbers, one, three, seven, and nine, ascending in order; on the right side are the yin numbers, four, two, eight, and six, descending in order. The number five is in the center. One combines with six to form water, three combines with eight to form wood, seven combines with two to form fire, nine combines with four to form metal, and five itself is earth, thus forming a principle of mutual interaction. Now observe: one and four, three and two, seven and eight, nine and six, each pair differs by five, which is precisely the number in the center. Therefore, although there are eight hexagrams, there are nine numbers, with the central number hidden within. This indicates that the essence of the hexagrams is invisible and only manifests through their functions.

乾用九，坤用六，為用之最大者，以陽極於九，陰終於六。九六為乾坤之用，即全易之用，故以九六代卦之用。九與六合為十五，成中央土數，即體也。體以用見，故乾坤以下各卦之用，皆為五，不違其體；體一而用殊，八卦各有所用，而體則一。

Heavenly Stem Qian uses nine and Earthly Stem Kun uses six, which are the largest numbers among all the numbers used. This is because the yang number reaches its peak at nine, and the yin number ends at six. Nine and six are the numbers used by Qian and Kun, meaning they represent the entire use of the Book of Changes. Therefore, the Book of Changes uses nine and six to represent the application of lines. When nine and six are added together, they total fifteen, which exactly corresponds to the number of the central earth. This is the fundamental essence. The essence becomes evident through its function, so the numbers used in the hexagrams following Qian and Kun all reduce to five, without contradicting this fundamental essence. Although there is only one fundamental essence, the functions differ: each of the eight trigrams has its own function, yet the fundamental essence remains the same.

五在中央，名為中數。中者天下之大本，八卦皆自此出，萬物皆歸於中道，此數之妙，亦氣之所存也。數以紀氣，氣行無垠，周流無息，而不離其宗，即永繫於中也。中之氣，先天之真，八卦之氣，兩儀之象，八卦有物。

Five is located in the center and is called the "central number." The concept of center is the great foundation of the world. The Eight Trigrams all originate from here, and all things ultimately return to the middle path. This is both the profound mystery of numbers and the place where qi resides. Numbers are used to record qi. The movement of qi has no boundaries and flows continuously, yet it never departs from its origin, which is always connected to this central point. The qi located in the center is the true qi of the Earlier Heaven. The qi of the Eight Trigrams is the manifestation of the two principles, and the Eight Trigrams are the embodiment of things in the physical world.

故氣有二，而成生化；有升降消長，而成變化。真氣無形，獨居中央，無動無變；八卦有名有數，中氣無名，而數以用成。此即伏羲本河圖之象，制卦象也。卦八用九，而不以九卦者，為示中氣之先天，而有異乎他物也。然有物，則有此氣；卦雖八，而中氣仍在，其妙義可見矣。

Therefore, qi is divided into yin and yang, enabling the process of generation and transformation. There must be rising and falling, as well as decrease and increase, in order to achieve change. As for true qi, it has no form or trace, resides in the center, remains unmoving and unchanging. Each of the eight trigrams has its own name and number, but the central qi has no name, and only manifests through numbers. This is precisely the reason why Fuxi based the trigrams on the imagery of the Yellow River Chart. Although there are only eight trigrams, the use of numbers involves nine positions. The reason for not including the ninth trigram is to indicate that the central qi belongs to the Earlier Heaven, differing from other tangible things. However, as long as there is something, this qi exists within it. Although there are only eight trigrams, the central qi still exists, and the profound meaning is evident here.

後天八卦之象，方位次序，均與先天異，以先天之已變也。其象本於洛書，而成二五交錯之用，故離上坎下，震東兌西；乾居西北，坤處西南；巽在東南，艮移東北。離陰而在上，坎陽而就下；震木在東，如日之出；兌金在西，如月之升；乾以金而連兌，巽以木而接震，同類相親也。坤以地而守南隅，艮以土而歸北角，土氣分佈也。陰陽皆交互以成生化，五行有生制以為功用，以其後天之象，必由二五之交錯、氣數之升降往來，而後見其生化，成其功用也。

The Later Heaven Trigrams differ in their arrangement and order from the Earlier Heaven Trigrams, because the Earlier Heaven has already changed. The Later Heaven Trigrams are based on the Luo Writing, forming a pattern where yin and yang energies and the Five Phases interact. Thus, Li is at the top, Kan at the bottom, Zhen in the east, Dui in the west; Qian is located in the northwest, Kun in the southwest; Xun is in the southeast, Gen moves to the northeast. Li is originally yin but is placed at the top, Kan is originally yang but is located at the bottom; Zhen, belonging to wood, is in the east, like the sun rising; Dui, belonging to metal, is in the west, like the moon rising in the east; Qian, belonging to metal, is connected to Dui, and Xun, belonging to wood, is connected to Zhen, all showing affinity among similar elements. Kun, representing earth, stays in the southwest corner, and Gen, representing earth, moves to the northeast corner, showing the distribution of earth energy at the two opposite corners. Yin and yang must interact to achieve generation and transformation, and the Five Phases must generate and control each other to function properly. It is precisely because the Later Heaven Trigrams must go through the interaction of yin and yang and the Five Phases, and the rising and falling of energies, that they can manifest generation and achieve their functions.

四 巽　　離 九；三 震　　坤 二；五；八 艮　　兌 七；一 坎　　乾 六

This is the diagram of the Later Heaven Trigrams, also arranged in five layers with left and right facing each other: the topmost layer has Xun four on the left and Li nine on the right; the second layer has Zhen three on the left and Kun two on the right; the central position still has a five; the fourth layer has Gen eight on the left and Dui seven on the right; the lowest layer has Kan one on the left and Qian six on the right. Compared to the Earlier Heaven diagram, the left and right sides are now counted from bottom to top, yin and yang alternate, and the central five remains in the middle position unchanged.

由八卦之序數之，則為乾、坎、艮、震、巽、離、坤、兌，循環以行，牽引以用；而其本數，則為坎一、坤二、震三、巽四、乾六、兌七、艮八、離九，其式仿洛書也。坎為一，自下始，左右皆由下上，陰陽皆交互行，不似先天在左上右下，左陽右陰，兩相對待，而未交合也。

Following the order of the Later Heaven Trigrams, they are arranged as Qian, Kan, Gen, Zhen, Xun, Li, Kun, Dui, circulating and interacting with each other to exert their effects. As for the numerical sequence, it is Kan one, Kun two, Zhen three, Xun four, Qian six, Dui seven, Gen eight, Li nine, with the diagram pattern modeled after the Luo Writing. Kan is assigned the number one, starting from the very bottom, with both left and right sides counted upward from the bottom. Yin and Yang interact with each other in this arrangement, unlike the Earlier Heaven arrangement where the left side goes upward and the right side downward, with all the left side being Yang and all the right side being Yin, opposing each other without merging. The Later Heaven arrangement changes to have both sides moving upward together because all things have already been generated, with Yin containing Yang and Yang containing Yin. The Qi no longer flows separately on each side but is intermingled and rises together. Kan being at the very bottom and assigned the number one also signifies that all generation and transformation in the Later Heaven begin from water, the source.

後天之象，在生化之後，本已交合，故氣為同化，數為連生。自坎至巽，為左之四卦；自乾至離，為右之四卦。其數原以一二三四居左，六七八九居右，而其中二八易位，坤艮易方，故左則坎一、坤八、震三、巽四，右則乾六、兌七、艮二、離九，以成後天之數，合乎洛書者也。

The Later Heaven arrangement arises after the process of generation and transformation, as yin and yang have already combined. Thus, the qi is mutually assimilated, and the numbers are continuously generated. From Kan to Xun, there are four trigrams on the left; from Qian to Li, there are four trigrams on the right. Originally, the numbers should be arranged as one, two, three, and four on the left, and six, seven, eight, and nine on the right. However, the numbers two and eight have exchanged positions, and as a result, the trigrams Kun and Gen have also exchanged their positions. Therefore, the left side becomes Kan one, Kun eight, Zhen three, and Xun four, while the right side becomes Qian six, Dui seven, Gen two, and Li nine. This forms the Later Heaven numbers, which correspond exactly with the Luo Writing.

洛書之數，二在西南，與七連；八在東北，與三接。正符河圖之數。二七為火，轉為金，三八為木也。故後天卦數，下則坎一與乾六合，上則巽四與離九合，金水為橫也；左則坤八震三合，右則艮二與兌七合，木火為縱也。

The numbers of the Luo Shu are arranged so that two is in the southwest and connects with seven; eight is in the northeast and connects with three. This exactly matches the numerical principles of the He Tu: two and seven originally belong to fire, but in the Later Heaven they become metal, while three and eight belong to wood. Therefore, the numbers of the Later Heaven hexagrams have the lower part combining Kan one with Qian six, and the upper part combining Xun four with Li nine, with metal and water running vertically through the top and bottom. On the left side, Kun eight combines with Zhen three, and on the right side, Gen two combines with Dui seven, with wood and fire extending horizontally on both sides.

以在後天金火易位，變為水火上下；金木東西，而巽木仍連震，乾金仍接兌，離與坎對，水火相交；坤與艮偶，土地分化，土為四季之旺，分佈於四行中，故土在後天，得時最多，以成生化之本也。

Because in the Later Heaven the metal and fire have exchanged positions, water and fire now occupy opposite positions; metal and wood are separated east and west, while the wood of Xun remains connected to Zhen, and the metal of Qian remains connected to Dui. Li (fire) and Kan (water) face each other, thus water and fire meet. Kun (earth) and Gen (mountain) form a pair, and the earth splits into the other four elements. Earth is prosperous and strong in all four seasons, distributed among the other four elements, so earth receives the most seasonal influence in the Later Heaven, thus becoming the fundamental source of generation and transformation.

水火既濟，則萬物以生；雷澤歸妹，則萬物以化；有地山之謙，以行其令，厚其德，則萬物以成，而後後天之用可見也。且以乾六與巽四合十，則天風姤之象，示氣之媾遇也；以坎一與離九合十，則水火即濟之象，示氣之交濟也。

Water and fire combine to form the hexagram of "Perfect Union," from which all things are born; thunder and marsh combine to form the hexagram of "Return of the Wife," from which all things are transformed; further, earth and mountain combine to form the hexagram of "Humility," used to regulate the seasons and accumulate virtue, from which all things are formed. Only then is the function of Later Heaven fully revealed. Furthermore, in terms of numbers: the number six of Heaven and the number four of Wind add up to ten, which is the image of the hexagram "Meeting," indicating the meeting and union of qi; the number one of Water and the number nine of Fire add up to ten, which is the image of "Perfect Union," indicating the mutual assistance of qi.

震三兌七亦合十，坤八艮二亦合十，則謙與歸妹之象，示氣之通貫和好也。氣皆交和，用乃宏大；數皆錯列，功乃周密。而體以用見，神以功名，則中數之五與十，仍存其中矣。此後天八卦之象，全本乎洛書者也。

The trigram Zhen three and Dui seven add up to ten, and Kun eight and Gen two also add up to ten, which corresponds exactly to the images of the hexagrams Qian and Guimiao, indicating the flow and harmony of qi. When qi is fully integrated and harmonious, its function can be great; when numbers are interwoven, their effects can be thorough. The essence is revealed through function, and the marvelous is known through effect. Thus, the middle number five and ten remain hidden within all of this. This is the image of the Later Heaven Trigrams, fully based on the Luo Writing.

周易一書，文王所本於連山、歸藏者，而復推衍其變，以與伏羲之作相證也。故卦象不異，而序異焉。文王六十四卦序，雖參伍錯綜，往復循環，與本宮本卦之序異，而仍不變其宗。宗者伏羲八卦之序是也，伏羲八卦為各易根本，無論何易，皆由其序而推衍之，故連山、歸藏、周易三者，其所宗皆同。

The book of Zhou Yi was composed by King Wen based on the two earlier books of Lian Shan and Gui Cang, and he further elaborated on their transformations to verify the old system of Fuxi. Therefore, the hexagrams themselves remained unchanged, only their order was altered. Although the order of the sixty-four hexagrams in King Wen's arrangement is complex and interwoven, differing from both the original sequence of the trigrams and the sequence of the primary hexagrams, its main principle has not changed. This main principle refers to the sequence of the eight trigrams of Fuxi. The eight trigrams of Fuxi are the foundation of all schools of Yi. No matter which school of Yi, it is derived from this sequence. Therefore, the three books of Lian Shan, Gui Cang, and Zhou Yi all revere the same main principle.

即本宮本卦，及六日七分、十二闢卦之序，亦自伏羲卦序所變，初無異也，其所異者，為其用耳。用者合于時宜，孚於人事，本於天道，翕於鬼神，而無間隔也。故夏有連山，商有歸藏，周有周易，時之殊也。

Even the sequence of the primary hexagrams, the order of the primary hexagram, the method of six days and seven parts, and the sequence of the twelve trigrams are all derived from the sequence of Fuxi's hexagrams, and their origins are fundamentally the same. The difference lies only in their respective applications. What is meant by application is to conform to the needs of the times and the actual circumstances of human affairs, to take the heavenly way as the foundation, and to harmonize with the principles of the spirits and ghosts in the unseen realm, without any barrier. Therefore, the Shang dynasty had the "Lianshan" (Continuous Mountains), the Zhou dynasty had the "Guicang" (Return to the Hidden), and the Zhou dynasty had the "Zhouyi" (Book of Changes), which resulted from differences in the times.

有天地之序，日月之度，歲時之歷，人物之生，幽明之道，不相侔者，則卦用以變。故有本宮、本卦、六日七分、闢卦之異，及夫納甲、納辰、納音、運氣、占候之差也。蓋卦以象物事，物事不一，則卦用不同；而卦之為卦，仍止六十四，其應於變者，唯有異其序。序異則用殊，雖卦同，而為象不同。

The order of heaven and earth, the measured movement of sun and moon, the calendar of the seasons, the growth of things and beings, and the principles between the hidden and the manifest—all these differ from one another. Therefore, the use of hexagrams must adapt accordingly. Hence there are differences such as the sequence of the primary hexagram, the sequence of the original hexagram, the six days and seven parts, and the distinction of hexagrams. There are also various methods such as "Najia," "Nachen," "Nayin," "Guqi," and "Zhanhou." Hexagrams are originally used to symbolize things, and since things are not all the same, their applications naturally differ. However, there are only sixty-four hexagrams. To deal with these changes, the order of the hexagrams must be altered. When the sequence changes, their function also changes: although the hexagrams remain the same, the images they represent have become different.

故各序皆有其象，以致其用，非重複也，亦別有他易，而異於伏羲文王之制也。制羲之制最古，時世簡樸，事物純省，故為序者少異例，以不用也，遞降而時移世易，物繁事多，則必推其變，以窮其用。而後序之異例日加，為易亦日眾，此自然之理也。苟有賢者，能通其變，則卦序猶可推衍之以應於用，亦如文王之變連歸為周易也。

Therefore, each type of ordering has its own symbolic meaning and is used for its particular function, not redundant work. It can also be said to form another kind of Book of Changes, distinct from the old systems of Fuxi and King Wen. Fuxi's system was the most ancient, when the world was simple and things were straightforward, so there were few variations in the ordering, as they were not needed. As time passed and the world changed, things became more complex and numerous, and affairs more complicated, it became necessary to elaborate on their changes in order to exhaust their uses. After that, variations in the ordering increased day by day, and the books of Changes also grew in number day by day, which is a natural development. If there were a wise person who could understand these changes, the order of the hexagrams could continue to be extended to meet new needs, just as King Wen transformed the books of "Lianshan" and "Guicang" into the "Zhou Changes."

故周易，文王之制，周代之作，為孚有周政教之用，應當時事物之變也。三代之政教極於周，故夫子刪訂以周易為主。周鑑二代，崇五帝，明周之作，即足概以上之制；取周易，足以窺各易之用也。然周易之序，序周時之政教，即足概以上之制；取周易，足以窺各易之用也。然周易之序，序周時之政教，應事物之變者，以後有所傳者、亦可輔周易而廣其用。

Therefore, the Zhou Yi was composed by King Wen and is a product of the Zhou dynasty, intended to meet the needs of the political and educational policies of the Zhou dynasty and to deal with the changes of things at that time. The political and educational systems of the Xia, Shang, and Zhou dynasties reached their peak in the Zhou dynasty, so when the Master edited the classics, he took the Zhou Yi as the main text. The Zhou dynasty drew lessons from the Xia and Shang dynasties and revered the Five Emperors, showing that the works of the Zhou people were sufficient to encompass the systems of previous dynasties. Taking the Zhou Yi alone is enough to see the methods used in the various schools of the Yi. The order of the Zhou Yi reflects the political and educational policies of the Zhou dynasty and responds to the changes of things. If there were other transmitted versions later on, they could also assist the Zhou Yi and expand its applications. (This passage has repetitions, caused by transmission and copying in old editions, and is kept as it was.)

非僅限於周易也，故於各序之列，有由來者，亦宜習之，以廣易道，而神變化，此固夫子之微意也。本宮之序，以乾、坤、坎、離、震、巽、艮、兌相對之卦次。如乾本宮卦，一世為姤，二世為遯，三世為否，則變於坤，四世為觀，五世為剝，皆坤卦所變；六世游魂為晉，則乾附於坤；七世歸魂為大有，則乾反於乾。

It is evident that one need not limit oneself to the book of The Zhou Changes. Therefore, all sequences that have a source should be studied, to broaden the path of divination and enhance the transformations within it. This was the profound meaning that the Master did not explicitly state. The order of this system is arranged according to the pairs of trigrams: Qian and Kun, Kan and Li, Zhen and Xun, Gen and Dui. For example, in the Qian trigram section: the main trigram is Qian, the first generation trigram is Gou, the second is Dun, the third is Pinyin, and at this point it transitions into the domain of Kun. The fourth generation trigram is Guan, the fifth is Bo, both derived from Kun. The sixth generation is the wandering soul trigram Jin, at which point Qian has become attached to Kun. The seventh generation is the returning soul trigram Da You, and Qian returns to Qian.

自本卦至三世，屬本宮所變；自四世至五世，屬對宮所變；六為附於對宮，故曰游魂，言在外也；七為返於本宮，故曰歸魂，言歸本也。此本宮之序例，以本位與對位，相生相變，次第以成。七世而終必有始，往必有復，故三變而易對宮，七變而還本位，與其本卦成一宮。八卦雖屬一宮，已見交錯往還之象，非純一宮卦也。

From the primary hexagram to the third generation hexagram, the changes occur within the same palace; from the fourth generation hexagram to the fifth, the changes occur between the opposing palace. The sixth change is attached to the opposing palace, so it is called "youhun," meaning being away from the original position. The seventh change returns to the original palace, so it is called "guihun," meaning returning to the source. This is the general pattern of the palace sequence: the original position and the opposing position generate and transform each other in sequence. The seventh generation hexagram marks the end. Since there is an end, there must be a beginning; since there is movement, there must be return. Therefore, the change occurs to the opposing palace at the third generation, and returns to the original position at the seventh generation. Together with the primary hexagram, they form a complete palace. Although the eight hexagrams in one palace belong to the same palace, they already show an image of mutual movement and exchange, and are not purely hexagrams within one palace.

蓋既有生化，必有陰陽；陽合於陰，陰交於陽，生化始成；陽還於陽，陰還於陰，循環始見。本來天地萬物生化，固如是也。故卦序象之，其異乎周易者，則所交錯往復，僅限於相對二宮，而不及他卦。故其所象者，先天初化，萬物始生，二氣初調，五行未雜，其數簡，其氣純，與周易之錯雜循環者異矣。

Since there is generation and transformation, there must necessarily be yin and yang: yang and yin come together, yin and yang interact, and thus generation and transformation can take place; yang returns to its place, yin returns to its place, and the cycle becomes evident. The generation and transformation of all things in heaven and earth are originally like this. Therefore, the order of the hexagrams imitates this process; its difference from the Zhou Changes lies in that the alternating and returning movements are confined within the two opposing trigrams, without involving the other hexagrams. Therefore, it symbolizes the stage when the Earlier Heaven is just beginning to transform, when all things are just beginning to emerge, when the two energies of yin and yang first harmonize, and when the Five Phases have not yet become mixed: the numbers are simple, the qualities pure, differing from the complex and intertwined cycles of the Zhou Changes.

且本宮之序為縱，周易之序為橫。本宮八卦，為一宮卦屬，而不連他宮卦。如乾宮各卦，皆屬金，納甲納辰皆同乾卦；唯游魂屬艮，歸魂屬坤，不同乎乾，以其氣變，數亦易也。氣變則改其情，數易則殊其名，此必至者也；然其大用，仍不離其宗。故所取者，仍本宮內之所合卦；如晉取艮，則遯卦之所合；大有取坤，則否之所合，個二世三世之卦也。

In addition, the order of the trigrams in each palace is arranged vertically, while the order of the Zhou Changes is arranged horizontally. The eight trigrams in a single palace belong to the same category and are not connected with trigrams from other palaces. For example, all trigrams in the Qian palace belong to the metal element, and both "Najia" and "Nachen" also correspond to the Qian trigram. Only the "youhun" trigram belongs to Gen and the "guihun" trigram belongs to Kun, which differ from Qian, because when the qi changes, the numbers also change. When the qi changes, the nature of the trigram changes; when the numbers change, the name of the trigram changes, which is a natural occurrence. However, their main use still remains within the main trigram of their palace. Therefore, when taking symbolic meanings, the trigrams within the same palace are still used to match: for example, the hexagram "Jin" takes Gen, which corresponds to the hexagram "Dun"; the hexagram "Dayou" takes Kun, which corresponds to the hexagram "Po" — that is, the two trigrams corresponding to the second and third generations.

夫卦在後天，以下卦為主；而本宮卦以上卦為先。如姤卦乾上巽下，不從巽而屬乾，則以卦之變自下始也。乾之變初爻為陰，則成巽，而姤卦出，故以下卦明變也。二變則為艮，三變則成坤，四以後所變者，上卦各爻，故反以對宮為主，而坤不動也；迄七變歸魂，而始還於本來，

When a hexagram reaches the Later Heaven arrangement, the lower trigram is the main focus; however, the native hexagram takes the upper trigram as the primary element. For example, the hexagram Gou (Encounter) has the trigram Qian (Heaven) as the upper trigram and Xun (Wind) as the lower trigram. It is not classified under the Xun trigram group but under the Qian trigram group, because the change in the hexagram begins from the lower trigram. The first line of the Qian trigram changes from yang to yin, transforming the lower trigram into Xun, and thus the hexagram Gou appears. Therefore, the change is shown through the lower trigram. The second change transforms the lower trigram into Gen (Mountain), the third change transforms it into Kun (Earth); from the fourth change onwards, the changes occur in the lines of the upper trigram, so the opposite trigram group becomes the main focus, and the lower trigram Kun no longer changes. This continues until the seventh change, when it becomes a returning soul hexagram, and then it begins to return to its original form.

而後後天之用見，如大有一卦，乾在下，與前一二三世相孚；而乾卦之氣乃完，生化循環之用乃盡；其序之次第，皆自然而然，亦猶天地生化之序也。乾宮如此，他宮亦然，其例皆同，不待盡述。

Thus the function of the Later Heaven arrangement becomes evident. For example, in the hexagram "Great Possession," the trigram Qian returns to the lower position, harmonizing with the previous hexagrams of the first, second, and third generations. At this point, the energy of Qian is complete, and the cycle of generation and transformation is fulfilled. The order of these sequences is naturally formed, just as the order of generation and transformation in heaven and earth. This is the case with the Qian trigram, and similarly applies to all other trigrams, following the same pattern, so there is no need to elaborate further.

本卦之序，有方圓二圖，即世傳之先天六十四卦方圓圖，宋人所得於道家者，實古人所留傳也。其序一依伏羲八卦位次之數，既乾一、兌二、離三、震四、巽五、坎六、艮七、坤八，全與河圖數合。乾與坤對，一始一終；離與坎對，一來一往；餘卦順序，分陰分陽，以明氣之升降、數之消長也。

The sequence of the primary hexagram has two forms: the square diagram and the circular diagram, which are the well-known Earlier Heaven sixty-four hexagram square and circular diagrams. These were obtained by people of the Song dynasty from Daoism, but in reality they are remnants passed down from ancient times. The order follows entirely the numerical positions of the Eight Trigrams as arranged by Fuxi. That is, Qian is first, Dui second, Li third, Zhen fourth, Xun fifth, Kan sixth, Gen seventh, and Kun eighth. This sequence corresponds completely with the numbers of the Yellow River Chart. Qian and Kun are opposite to each other, one being the beginning and the other the end; Li and Kan are opposite, one coming and the other going; the rest of the hexagrams are arranged in order, divided into yin and yang, to indicate the rising and falling of qi and the waxing and waning of numbers.

自乾卦始，為一之一，屬乾卦者則為夬、大有、大壯、小畜、需、大畜、泰八卦。順序數之，則夬為兌乾合，為一之二；大有為離乾合，為一之三；大壯為震乾合，為一之四；小畜為巽乾合，為一之五；需為坎乾合，為一之六；大畜為艮乾合，為一之七；泰為坤乾合，為一之八。

Starting from the Qian Trigram, the first one is numbered one; the trigrams belonging to Qian are the Gua, Da You, Da Zhuang, Xiao Xu, Xu, Da Xu, and Tai. Following the order, Gua is composed of upper Dui and lower Qian, numbered two; Da You is composed of upper Li and lower Qian, numbered three; Da Zhuang is composed of upper Zhen and lower Qian, numbered four; Xiao Xu is composed of upper Xun and lower Qian, numbered five; Xu is composed of upper Kan and lower Qian, numbered six; Da Xu is composed of upper Gen and lower Qian, numbered seven; and Tai is composed of upper Kun and lower Qian, numbered eight.

是八卦皆屬乾卦所合而生者。乾之所生八卦，凡乾在下者，無論上卦何屬，皆歸乾，其次第則全依先天數；自一至八，一為乾、八為坤，相循環也，故皆相對。其次則兌卦所屬，自履始，為乾兌，為二之一。

These eight trigrams are all derived from the Qian trigram. The eight trigrams generated by Qian, whenever the lower trigram is Qian, regardless of which trigram is the upper one, are all classified under Qian. Their order follows the Earlier Heaven sequence, numbered from one to eight, with one being Qian and eight being Kun, forming a cycle from beginning to end, thus each pair is opposite. Next comes the group associated with the Dui trigram, starting with the Lu hexagram: Lu is upper Qian and lower Dui, numbered as the second trigram.

次為兌卦，為二之二；次為離兌之暌，為二之三；次為震兌歸妹，為二之四；次為巽兌之中孚，為二之五；次為坎兌之節，為二之六；次為艮兌之損，為二之七；次為坤兌之臨，為二之八。

Next is the hexagram "Dui" (Joy), with both lines being Dui, numbered 2.2; below it is the hexagram "Kui" (Strife), with upper Li and lower Dui, numbered 2.3; below that is the hexagram "Gui Mei" (Return of the Wife), with upper Zhen and lower Dui, numbered 2.4; below that is the hexagram "Zhong Fu" (Sincerity), with upper Xun and lower Dui, numbered 2.5; below that is the hexagram "Jie" (Regulation), with upper Kan and lower Dui, numbered 2.6; below that is the hexagram "Sun" (Loss), with upper Gen and lower Dui, numbered 2.7; below that is the hexagram "Lin" (Approach), with upper Kun and lower Dui, numbered 2.8.

是八卦皆屬兌卦所合而生者，故為兌卦屬；而其數以兌屬先天數二，故皆統於二，猶乾所統於一也。以下各卦皆依此例，以迄於坤卦，為八之八，而殿六十四卦焉。

These eight trigrams are all derived from the Dui trigram, so they all belong to the category of Dui; as for their numbering, since Dui is the second in the Earlier Heaven sequence, this group is all classified under number two, just as the Qian trigram group is classified under number one. The following trigrams follow the same pattern, continuing up to the Kun trigram, which is numbered eight within the eighth group, concluding the entire sequence of sixty-four trigrams.

乾始坤終，乾一坤八，氣數相得，而成全易之序，為圖或方或圓皆同也。蓋此卦序，純本先天之象，以明天地物事之序，有所定也。位有定方，至有定時，上下有次，左右有紀，升降有度，往復有制，不相差於黍粒，不相失於毫毛。故其致用不同後天，而異乎周易之序，且不同先天生化之例，而異乎本宮各卦之序。

The trigrams begin with Qian (Heaven) and end with Kun (Earth), with Qian occupying the first position and Kun the eighth. The interaction between qi (vital energy) and numbers establishes the entire sequence of the Yi (I Ching). Whether drawn as a square or circular diagram, the principle remains the same. This sequence of trigrams is purely based on the Earlier Heaven pattern, used to explain the ordered nature of heaven, earth, and all things. Directions have fixed positions, arrival has fixed times, up and down have fixed order, left and right have fixed rules, ascent and descent have fixed measures, and movement and return have fixed limits. There is no deviation as small as a grain of millet or a hair's breadth. Therefore, its application differs from the Later Heaven system, and it differs from the sequence in the Zhou Yi. It does not follow the model of the Earlier Heaven's creation and transformation, so it also differs from the sequence of trigrams within the same palace.

其象之所指，為明先天之物與事，俾知氣數之本源，而得生化之初象。方以象地，圓以象天，天地既立，萬有斯定。故其制為道家所重，實足以探先天之奧，明無為之道，超形跡之上，達天人之源者，惜乎世人未知其用耳。

This diagram illustrates the principles of the Earlier Heaven, explaining the origins of qi and things, so that people may understand the fundamental source of generation and transformation. The square diagram symbolizes the earth, while the circular diagram symbolizes the heaven. Once heaven and earth are established, all things follow accordingly. Therefore, this system is highly valued by Daoists, as it is indeed capable of exploring the mysteries of the Earlier Heaven and elucidating the way of non-action. It can transcend physical forms and directly reach the common origin of heaven and humanity; the regret is that people do not understand its use.

本卦序與本宮序，二者有可印證處。如本卦乾卦所生八卦，夬、大有、大壯、小畜、需、大畜、泰諸卦，合之本宮，則僅本卦之乾，與歸魂之大有，屬乾宮；

The sequence of the primary hexagrams and the sequence of the native hexagrams can be cross-referenced with each other. For example, among the eight trigrams generated from the Qian hexagram in the sequence of primary hexagrams—such as Gua of Guai, Da You, Da Zhuang, Xiao Xu, Xu, Da Xu, and Tai—it is only the primary hexagram Qian and the returning soul hexagram Da You that truly belong to the Qian palace when checked against the sequence of the native hexagrams.

合之本宮，則僅本卦之乾，與歸魂之大有，屬乾宮；其泰、大壯、夬、需四卦，則屬對宮坤宮；其小畜、大畜二卦，則一屬巽宮，一屬艮宮。是八卦分屬四宮也。而所屬者，仍與本宮之例合。如對宮四卦，原由本宮變；乾坤對變，原定例也。

In the "Primary Hexagram Sequence," the eight trigrams generated by the Qian hexagram are compared with the "Primary Palace Sequence." Only the Qian hexagram itself and the returning soul hexagram Dali belong to the Qian palace. The four hexagrams Tai, Da Zhuang, Guai, and Xu are all assigned to the opposite palace, Kun palace. The two hexagrams Xia Xu and Da Xu are assigned to the Xun palace and Gen palace respectively. This shows that these eight trigrams belong to four different palace groups. However, their assignments still conform to the general rule of transformation within the same palace: the four hexagrams that are assigned to the opposite palace were originally generated from their own palace. Qian and Kun are opposite palaces that transform into each other, which is a fixed rule established in the arrangement of the eight palaces.

大小畜二卦，雖非本對宮，而小畜由巽合，即本宮一世之所變；大畜與艮合，即本宮二世之所變。本宮一世為姤，亦變巽也；二世為遯，亦變艮也。卦雖不同，所合之例仍同。

The hexagrams Xiao Xu and Da Xu, although not derived from the opposite trigram of Qian, are formed by the combination of Qian with Xun for Xiao Xu, corresponding to the first generation hexagram of the Qian palace; and by the combination of Qian with Gen for Da Xu, corresponding to the second generation hexagram of the Qian palace. The first generation hexagram of the Qian palace is Gou, whose lower trigram is Xun; the second generation hexagram is Duan, whose lower trigram is Gen. Therefore, although the names of the hexagrams are different, the principle of their combination remains consistent.

故本宮乾宮八卦，由對宮與對宮合變者，亦四卦；與巽艮合變者，亦二卦。是與本卦之變例，異而不異也。坤卦亦然，所屬八卦除本宮外，亦屬乾宮者四卦，屬震兌二者二卦，與本宮之變例皆同。

Therefore, among the eight trigrams governed by the Qian trigram, those transformed through the opposite trigram Kun and those combined with the opposite trigram are exactly four trigrams; those combined with Xun and Gen produce exactly two trigrams. This shows that the rules of change in the "primary hexagram sequence" and the "governed trigram sequence" appear different but are actually the same. The Kun trigram is also the same: among the eight trigrams generated by Kun, excluding those still belonging to the Kun trigram group, four trigrams are assigned to the opposite trigram group Qian, and two trigrams are assigned to the Zhen and Dui trigram groups, which completely conform to the transformation rules of the Kun trigram group.

故卦雖殊，氣之所合不殊也。乾之氣由西下，而與對宮坤合；坤之氣由東上，而與對宮乾合。無論何序，其例不差，蓋天地陰陽之氣，原來如是也。凡本卦各卦，皆以陰陽升降，本對合化，而生各卦，其例不亂，故其序有定，如指與臂；其象有數，如線串珠；無或差池，無少凌亂。

Therefore, although the names of the hexagrams differ, their essential nature remains the same. The energy of Qian comes from the west and descends, thus combining with Kun in the opposite direction; the energy of Kun rises from the east, thus combining with Qian in the opposite direction. No matter which sequence of hexagrams is used, this principle remains correct, because the yin and yang energies of heaven and earth naturally operate in this way. All the hexagrams in the 'Primary Hexagram Sequence' arise through the interaction of yin and yang rising and falling, and the combination of the original hexagram with its opposite. The order is perfectly consistent. Therefore, its sequence is fixed, like fingers connected to the arm in a natural way; its hexagram images are definite, like beads strung on a thread, orderly and without any disorder or confusion.

不過本卦之序，明先天之真，由下而上，以返本復始，故其卦以下卦為主；本宮序則為明後天之象，由內而外，溯源達流，故其卦以上卦為本。一自下而上，一自上而下，其變化次序不同耳。

The "primary hexagram sequence" aims to reveal the truth of the Earlier Heaven, taking the direction of moving upward from the lower to return to the source and start anew, so when arranging the hexagrams, the lower trigram is taken as the main one. The "primary palace sequence" aims to reveal the image of the Later Heaven, taking the direction of moving outward from the inner to the outer, from the source to the end, so when arranging the hexagrams, the upper trigram is taken as the basis. One goes from bottom to top, the other from top to bottom; the difference between them is merely the direction of the order of change.

苟細按之，自得其故。如為人事吉凶，物理變化，則本宮之序，便於用也；如為天道往復，元氣動靜，則本卦之序，得其真也。故術家卜筮，必取本宮飛伏納甲之圖；而道家修恃，必重本卦方圓合數之象。皆易中精妙，非淺識可得；此不過舉其大要，以明其用耳。

As long as one carefully investigates, the underlying reasons will naturally become clear. If one wishes to predict the fortune or misfortune of human affairs or the changes in the principles of things, using the 'Sequence of the Palace' is most convenient. However, if one aims to observe the cyclical movement of heaven's path and the dynamic stillness of the vital energy, then the 'Sequence of the Primary Hexagram' is most accurate. Therefore, in divination, practitioners of numerology and divination must use the 'Flying and Hidden' and 'Najia' diagrams of the Palace. Meanwhile, those engaged in Daoist cultivation must emphasize the hexagrams of the Primary Hexagram, both the square and circular diagrams, which conform to the numerical principles. These are the subtle aspects of the Book of Changes, not something that can be understood by those with shallow insight. Here, only the main points are mentioned to illustrate their respective uses.