An Exposition of the Zhou Changes, compiled by Hui Dong.

乾元亨利貞。注：元，始；亨，通；利，和；貞，正也。乾初為道本，故曰元。息至二升坤五，乾坤交，故亨。乾六爻二四上匪正，坤六爻初三五匪正。乾道變化，各正性命，保合大和，乃利貞。傳曰：利貞，剛柔正而位當也。

The text says: Qian, Yuan, Heng, Li, Zhen. Hui Dong's commentary: "Yuan" means the beginning, "Heng" means smooth passage, "Li" means harmony, and "Zhen" means firmness. The first line of the Qian hexagram represents the fundamental principle of the heavenly way, hence it is called "Yuan." Yang energy grows (the "xi" or breath) to the second line, then ascends to occupy the fifth line of the Kun hexagram, which is the position of the heavenly sovereign. Thus, the Qian and Kun hexagrams communicate and interact, hence it is called "Heng." Among the six lines of the Qian hexagram, the second, fourth, and top lines are yang lines in yin positions, which are inappropriate; among the six lines of the Kun hexagram, the first, third, and fifth lines are yin lines in yang positions, which are also inappropriate. The movement and transformation of the heavenly way enable all things to maintain their proper nature and heavenly mandate, nurturing and preserving the great harmony, which is what "Li Zhen" signifies. The "Commentary on the Changes" says: "Li Zhen" refers to both yang and yin lines returning to the correct positions, and all lines being in appropriate positions.

疏：《繋》上曰：「大衍之數五十，其用四十有九。分而為二以象兩，掛一以象三，揲之以四以象四時，歸奇於扐以象閏。」又《繋》下曰：「易有太極，是生兩儀，兩儀生四象，四象生八卦。」虞翻注云：「兩儀，乾坤也。庖羲幽贊於神明而生蓍，演三才五行而為大衍之數五十，其一大極，故用四十有九，即蓍之數也。」

Hui Dong's commentary states: The "Xici Shang Wen" says: "The number of yarrow stalks used in the great derivation is fifty, but only forty-nine are actually used. First, they are split into two groups at random, symbolizing the two principles of heaven and earth. Then one stalk is held between the fingers, symbolizing the three elements of heaven, earth, and humanity. Then they are counted in groups of four, symbolizing the four seasons of spring, summer, autumn, and winter. The remaining number, which is less than four, is placed between the fingers, symbolizing the intercalation method in the calendar." The "Xici Xia Wen" also says: "The Book of Changes contains the Taiji, from which the two principles arise, from which the four images arise, and from which the eight trigrams arise." Yu Fan explained: "The two principles refer to Qian and Kun. Fuxi deeply explored the principles of the divine and created the yarrow stalk divination. By deducing the numbers of the three elements and the Five Phases, he arrived at the number fifty for the great derivation. One stalk represents the unchanging Taiji, so only forty-nine are actually used, which is the number of yarrow stalks used in divination."

大極生兩儀，故分而為二以象兩；又分天象為三才，故掛一以象三；播五行於四時，故揲之以四以象四時；乾坤之筴當期之日，以閏月定四時成歲，故歸奇於扐以象閏，所謂兩儀生四象也。四營而成易，十有八變而成卦，是生八卦而小成，所謂四象生八卦也。引信三才，至萬有一千五百二十而六十四卦備矣。此聖人作八卦之事也。

The Taiji gives rise to the two principles, so the divination stalks are divided into two bundles to symbolize the two principles; the celestial phenomena are divided into the three elements of heaven, earth, and humanity, so one stalk is hung to symbolize the three elements; the five phases are spread throughout the four seasons, so counting by four stalks each time symbolizes the four seasons; the number of the trigram Qian is 216 and that of Kun is 144, together they correspond to the number of days in a year, and with the adjustment of a leap month, the four seasons form a year, so the remaining stalks are held between the fingers to symbolize the leap month—this is called "the two principles give rise to the four images." When the four steps of divination are completed, one change is made; after eighteen changes, one hexagram is formed, and the eight trigrams are first obtained, called "small completion"—this is called "the four images give rise to the eight trigrams." From this, the numbers of the three elements are extended until reaching the number 10,152, and the sixty-four hexagrams are thus complete. The above describes the process by which the sage created the eight trigrams.

乾坤，陰陽之本，故首乾坤。元始、亨通、利和、貞正，子夏義也。元始，《釋詁》文。亨者，乾坤交也。乾天坤地，天地交為泰。《序卦》曰：「泰者，通也。」故知亨為通也。《說文》曰：「利從刀，和然後利，從和省。」《文言》曰：「利者，義之和也。」又曰：「利物足以和義。」故知利和也。貞正也者，《師》彖傳文。

The hexagrams Qian and Kun are the sources of yin and yang, so the Zhou Changes begins with them. The term "Yuan" is interpreted as "beginning," "Heng" as "communication," "Li" as "harmony," and "Zhen" as "correctness," according to Zixia's Commentary on the Changes. The term "Yuan" being interpreted as "beginning" is found in the Er Ya, a dictionary of words. "Heng" is interpreted as "communication" because it refers to the interaction between Qian and Kun. Qian represents Heaven and Kun represents Earth; when Heaven and Earth interact, the hexagram Tai is formed. The Xugua Zhuan says, "Tai means communication," so "Heng" should be interpreted as "communication." The Shuowen Jiezi says, "The character 'Li' is composed of a knife, indicating that after harmony is achieved, there is benefit. The character form takes the abbreviation of 'he.' " The Wenyan Zhuan says, "Li refers to the harmony of principles." It also says, "When all things receive their benefit, it is sufficient for the harmony of principles." Therefore, "Li" should be interpreted as "harmony." As for "Zhen" being interpreted as "correctness," it originates from the Taijue Zhuan of the hexagram Shi.

乾初謂初九也。初，始也；元亦始也。何休注《公羊》曰：「元者，氣也，天地之始。」故傳曰：「大哉乾元，萬物資始。」《說文》曰：「元從一。」故《春秋》一年稱元年。《說文》又曰：「唯初大始，道立於一，造分天地，化生萬物。」董子對策曰：「謂一為元者，視大始而欲正本。」是乾初為道本，故曰元也。初九注云：「大衍之數虛一不用，謂此爻。」故謂之道本。

"The 'Qian Chou' refers to the first line of the Qian hexagram, 'Nine at the Beginning.' 'Chou' means beginning, and 'Yuan' also means beginning. He Xiu's commentary on the 'Spring and Autumn Gongyang Zhuan' says: 'Yuan is the vital energy, the beginning of heaven and earth.' Therefore, the 'Commentary on the Judgment' states: 'How great is Qian Yuan, by which all things have their beginning.' The 'Shuo Wen Jie Zi' says: 'The character Yuan is composed of 'one.' Hence, in the 'Spring and Autumn' chronology, the first year is called 'Yuan Nian.' The 'Shuo Wen' also says: 'Tai Chu is the greatest beginning, the Dao originates from 'one,' thereby distinguishing heaven and earth and nurturing all things.' Dong Zhongshu's response says: 'Calling 'one' as 'Yuan' is focusing on Tai Chu to correct the fundamental principle.' From this we can see that the first line of the Qian hexagram is the fundamental principle of the heavenly way, hence it is called 'Yuan.' Hui Dong in his commentary on the first line says: 'In the great derivation calculation, one root is left unused, referring to this line.' Therefore, it is called 'Dao Ben.' "

乾坤，消息之卦。乾息坤消，息至二當升坤五為天子，乾坤交通，故亨。經凡言亨者，皆謂乾坤交也。「乾六爻二四上匪正，坤六爻初三五匪正」，虞翻義也。二四上以陽居陰，初三五以陰居陽，故皆不正。乾變坤化，六爻皆正，故各正性命。乾為性，巽為命也。乾坤合德，六爻和會，故保合太和。正即貞，和即利，故乃利貞。

Heaven and Earth are the trigrams of "message" or "change": Heaven represents the growth of yang energy (growth), and Earth represents the retreat of yin energy (decline). When yang energy reaches the second line, it should ascend to the fifth line of the Earth trigram, which is the position of the Son of Heaven. Thus, Heaven and Earth communicate, and this is called "smoothness" or "success." Whenever the text mentions "smoothness," it refers to the mutual interaction between Heaven and Earth. Yu Fan said: "In the six lines of Heaven, the second, fourth, and top lines are not properly positioned; in the six lines of Earth, the first, third, and fifth lines are not properly positioned." The second, fourth, and top lines are originally yin positions but are occupied by yang lines, while the first, third, and fifth lines are originally yang positions but are occupied by yin lines, so they are all considered improperly positioned. After the lines of Heaven change and the lines of Earth transform, all six lines return to their proper positions, so it is said "each corrects its nature." Heaven symbolizes innate nature, and Wind symbolizes heavenly mandate. The virtues of Heaven and Earth combine, and the six lines harmonize and gather, so it is said "maintaining the great harmony." "Correct" is equivalent to "贞" (constancy), and "harmony" is equivalent to "利" (beneficial), so it is said "thus it is beneficial to be constant."

傳曰「利貞，剛柔正而位當也」者，《既濟》彖傳文。六爻皆正，故剛柔正而位當。經凡言利貞者，皆爻當位，或變之正，或剛柔相易。經惟《既濟》一卦六爻正而得位，故云剛柔正而位當。乾用九，坤用六，成既濟定，《中庸》所謂「致中和，天地位焉，萬物育焉」是也。此聖人作易之事也。

The Commentary on the Judgment says, "It is advantageous to maintain the correct course, because the yin and yang lines are properly positioned." This is the original text of the Commentary on the Judgment for the Hexagram of Completion. All six lines are in proper position, so it is said that the yang lines and yin lines are each in their correct positions and their positions are appropriate. In the text of the Classic, whenever it speaks of "advantageous to maintain the correct course," it refers to the lines already being in proper position, or lines that have moved from incorrect to correct positions, or the yang and yin lines having exchanged positions. Among the sixty-four hexagrams, only the Hexagram of Completion has all six lines properly positioned and each in its correct place, so it is said, "the yin and yang lines are properly positioned." The use of "All Nines" in the Hexagram of Heaven and "All Sixes" in the Hexagram of Earth, after their transformation, result in the fixed state of the Hexagram of Completion. This is what the Doctrine of the Mean refers to as "when the mean is achieved, heaven and earth are in their proper places and all things are able to flourish." The above discusses the matter of the sage's creation of the Zhou Changes.

初九潛龍勿用。注：易逆數也，氣從下生，以下爻為始，乾為龍，陽藏在下，故曰潛龍。其初難知，故稱勿用。大衍之數虛一不用，謂此爻也。九二見龍在田，利見大人。注：坤為田，大人謂天子。二升坤五，下體離，離為見，故曰見龍在田。群陰應之，故曰利見大人。

The text says: Initial Nine, the dragon is hidden and does not act. Hui Dong's commentary: The Book of Changes counts upwards, so the energy arises from below, hence the first line is taken as the starting point. Qian represents the dragon, and at this time the yang energy is hidden in the lower position, so it is called "the hidden dragon"; it has just begun to emerge, its form is not yet clear, hence it says "not to act." The number of the Great Derivation leaves one line unused, which refers precisely to this line. The text says: Nine in the Second, the dragon appears in the fields, favorable to meet a great person. Hui Dong's commentary: Kun represents the fields, "great person" refers to the Son of Heaven. Nine in the Second rises to the fifth position of Kun, forming the body of Li below, Li symbolizes appearance and meeting, hence it says "the dragon appears in the fields"; all the yin lines of Kun respond to it, hence it says "favorable to meet a great person."

九三君子終日乾乾，夕惕若夤，厲無咎。注：三於三才為人道，有乾德而在人道，君子之象。惕，懼；夤，敬；厲，危也。離為日，坤為夕，以乾接乾，故曰乾乾。四變坎為惕，乾為敬，故夕惕若夤。三多凶，故厲；因時而惕，故無咎。俗本脫夤，今從古。

The text says: Nine in the Third, the gentleman is diligent and unremitting all day, still cautious and respectful by evening, though in a dangerous situation, there is no fault. Hui Dong's commentary: The third line belongs to the human element among heaven, earth, and humanity. It possesses the vigorous virtue of Qian and is in the position of humanity, thus representing the image of the gentleman. "Tì" means caution, "Yín" means respect, and "Lì" means danger. Li symbolizes the daytime, while Kun symbolizes dusk; Nine in the Third is above the outer trigram Qian, so it is Qian supporting Qian, hence called "Qian Qian." The fourth line changes into Kan, which has the image of worry and caution; Qian also has the meaning of respect and caution, thus saying "evening caution as if respectful." The third line is often associated with misfortune, hence called "danger"; but because it is cautious according to the time, it does not bring calamity. The common version omits the character "Yín," here following the ancient text.

九四或躍在淵無咎。注：躍，上也；淵謂初。四失位，故上躍。居五者，欲下居坤初，求陽之正，故無咎。九五飛龍在天，利見大人。注：五體離，離為飛，五在天，故曰飛龍在天。二變應之，故利見大人。虞氏謂文王書經繋庖犧於乾五，造作八卦，備物致用，以利天下，天下之所利見是也。

The text says: Nine in the Fourth, perhaps leaps upward, perhaps remains in the deep abyss, without fault. Hui Dong's commentary states: "Leap" refers to upward movement, and "abyss" refers to the First Line. Nine in the Fourth, being a yang line in a yin position, is out of place, hence it leaps upward; the idea of occupying the fifth position originally meant to descend and occupy the first position of the坤 (Earth) trigram, so that each yang line is in its proper place, thus there is no fault. The text says: Nine in the Fifth, the dragon flies and ascends to the sky, favorable for meeting a great person. Hui Dong's commentary states: Nine in the Fifth is located in the upper trigram, which is Li (Fire), symbolizing flying and rising; Five also occupies the heavenly position, hence it is said "the dragon flies in the sky"; Nine in the Second changes to correspond with it, hence "favorable for meeting a great person." Yu Fan believes that King Wen composed the text, attaching Fuxi to the Nine in the Fifth of the Qian (Heaven) trigram, saying that he created the eight trigrams, perfected objects to their full use, and benefited the world, which is exactly the great person that the people delight in seeing.

上九忼龍有悔。注：窮高曰忼。陽極於上，當下之坤三，失位無應，窮不知變，故有悔。用九。注：九六者，爻之變。坤為用，發揮於剛柔而生爻，立地之道，故稱用也。見群龍無首吉。注：群龍，六龍也。時乘六龍以御天，故曰見群龍。乾為首，坤下承之，故無首吉。象曰：天德不可為首也。

The text says: Upper Nine, a lofty dragon will have regret. Hui Dong's own commentary: reaching the highest point is called "kang." Yang energy rises to the utmost and reaches its limit, it should descend to the third line of the Kun hexagram. Now that it has lost its position and has no responding line, it reaches its limit without knowing change, hence there is regret. The text says: Using Nine. Hui Dong's own commentary: Nine and Six refer to the movement of lines. Kun is "use," it generates lines by acting between yin and yang, establishing the way of the earth, hence it is called "use." The text says: A group of dragons appear, none taking the lead, which is auspicious. Hui Dong's own commentary: "Group of dragons" refers to six dragons. The "Commentary on the Judgment" says riding six dragons in accordance with time to govern the heavenly way, hence it says "seeing a group of dragons." Qian symbolizes the head, Kun is below supporting it, hence "without a head" brings auspiciousness. The "Image Commentary" says: Heavenly Virtue cannot take precedence.

疏：「易逆」至「爻也」。《說卦》云：「易逆數也。」注云：「易氣從下生，故云逆數。」《繋》上曰：「錯綜其數。」虞翻彼注云：「逆上曰錯，卦從下升，故曰錯綜其數。」《乾鑿度》曰：「易氣從下生。」鄭玄注云：「易本無形，自微及著，故氣從下生，以下爻為始」是也。

Hui Dong's commentary on the passage (commentary on the section from "The Book of Changes is counted in reverse order" to "this line") states: The "Say of the Trigrams" says, "The Book of Changes is counted in reverse order." The annotation explains that the energy of the Book of Changes arises from the bottom upwards, hence called "reverse counting." The "Xici Upper Transmission" says, "interweaving and combining its numbers." Yu Fan notes there, "counting upwards in reverse is called '错' (interweaving), and the hexagram grows from the bottom upwards, hence it is said 'interweaving and combining its numbers.'" The "Qianzuo Du" says, "the energy of the Book of Changes arises from below." Zheng Xuan annotates, "the Book of Changes originally has no form, it moves from subtle to manifest, so the energy arises from below, taking the lowest line as the starting point." This is exactly the same principle.

乾為龍，九家《說卦》文。乾之所以取象於龍者，《管子》曰：「伏闇能存而能亡者，蓍龜與龍是也。龜生於水，發之於火，於是為萬物先，為禍福正。龍生於水，被五色而遊，故神。欲小則化如蠶蠋，欲大則藏於天下，欲尚則陵於雲氣，欲下則入於深泉，變化無日，上下無時，謂之神。龜與龍，伏闇能存而能亡者也。」

"The trigram Qian represents the dragon," as stated in the Jiujia version of the "Shu Guan Zhuan." The reason why Qian is associated with the dragon is clearly explained in the "Guanzi": "Those that can exist and disappear in the dark are the yarrow stalks, the tortoise shell, and the dragon. The tortoise lives in water but requires fire to produce omens, thus it can be the first among all things and determine the correctness of fortune and misfortune. The dragon lives in water, adorned with five colors, and thus is extraordinary: it can become small like a silkworm, or large enough to hide throughout the world, or ascend above the clouds, or descend into deep springs. Its transformations are not bound by days, and its ascents and descents are not restricted by time. This is called divine. The tortoise and the dragon are precisely those that can exist and disappear in the dark."

若然，乾之取象於龍，以其能變化也。《荀子》曰：「變化代興，謂之天德。」天德，元也。天之元兼五色，故龍被五色。《文言》曰：「潛龍勿用，下也。」又曰：「陽氣潛藏。」故曰潛龍。「其初難知」，下《繋》文。初尚微，故難知。

Looking at this, the trigram Qian is taken as representing the dragon because it is capable of transformation. The "Xunzi" says: "The alternation and transformation of yin and yang arise, which is called Heavenly Virtue." Heavenly Virtue is also referred to as "Yuan." The Heavenly Principle (Yuan) encompasses the five colors, so the dragon is said to be adorned with five colors. The "Wenyan Zhuan" says: "The hidden dragon is not yet in use, because it is in the lowest position." It also says: "Yang energy is still concealed." Therefore, it is called "the hidden dragon." The phrase "its initial state is difficult to know" comes from the "Xici Zhuan." The phenomenon of the first line is still subtle, so it is hard to see clearly.

荀爽注「大衍之數五十」云：「乾初九潛龍勿用，故用四十九。」初九，元也，即太極也。太極函三為一，故大衍之數虛一不用耳。若然，用九之義六龍皆御，而初獨不用者，但易有六位，乾稱六龍，六位之成、六龍之御皆有其時，初當潛隱，故稱勿用。然萬物所資始，王位在德元，以一持萬，以元用九，吾道之貫、天下之治，皆是物也。

Xun Shuang's commentary on "The Great Derivation Number is Fifty" says: "The first yang line of the Qian hexagram is the hidden dragon that should not be used, so only forty-nine are used." The first yang line is "Yuan," which is the Taiji. The Taiji contains three and returns to one, so one is left out in the Great Derivation Number. According to this, the meaning of "All Nines" should be six dragons jointly governing the heavenly way, so why is the first yang line not used? Because the Book of Changes has six lines, and the Qian hexagram refers to six dragons. The accomplishment of the six positions and the governance of the six dragons each have their own time; the first yang line is at the time of concealment, hence it is said "should not be used." However, all things depend on it for their beginning, and the position of the king is also connected to "De Yuan." Using one to govern all things, using Yuan to manage the nine; Confucius' statement "My way is to be unified through one principle" and the reason why the world is governed well, all refer to the same thing.

「坤為」至「大人」。此荀爽義也。與坤旁通，坤土稱田。《釋言》曰：「土，田也。」《太玄》曰：「觸地而田之。」故曰坤為田也。許慎《五經異義》曰：「《易》孟京說，有君人五號：帝，天稱也；王，美稱也；天子，爵號，三也；大君者，與上行異，四也；大人者，聖明德備，五也。」其說本《乾鑿度》。是大人與天子同在五號之中，故云大人謂天子。王肅謂聖人在位之目，義亦同也。

Hui Dong's commentary (self-commentary from "Kun represents field" to "favorable to see a great man") states: This is Xun Shuang's view. Qian and Kun "mutually communicate," meaning the two trigrams have their six lines entirely opposite in yin and yang, being complementary to each other. Kun represents earth, and earth is called field. The Er Ya says: "Earth is field." The Tai Xuan says: "To touch the land and cultivate it." Therefore, Kun represents field. Xu Shen's Wujing Yiyi says: "The school of Change, the Meng family and Jing family, refer to the ruler with five titles: 'Emperor' is the title matching heaven; 'King' is a respectful term; 'Son of Heaven' is a rank, third; 'Great Lord' differs from the previous ones, being fourth; 'Great Man' refers to a sage with complete virtue, being fifth." This view comes from the Qian Zao Du. Thus, "Great Man" and "Son of Heaven" are both among the five titles, so "Great Man" refers to the Son of Heaven. Wang Su believes "Great Man" is the title of a sage in office, which is consistent with this meaning.

九二陽不正，故當升坤五。五降二體離，《說卦》曰：「相見乎離。」故離為見。二升坤田，故見龍在田。坤群陰應之，故利見大人也。「三於」至「之象」。此鄭玄義也。五爻皆有龍象，三獨稱君子者，以易有三才，三於三才為人道。《文言》曰：「君子行此四德者，故曰乾元亨利貞。」是君子為有乾德而在人道者。經凡言君子皆謂九三也。

Nine two, with a yang line in a yin position and not in the correct place, should ascend to the fifth position of the坤卦. The fifth line of坤 descends to the second position, and the lower trigram becomes the structure of the离卦. The "Sayings of the Trigrams" states, "They meet at the离," so the离 has the image of "seeing." When nine two ascends to the fifth position of坤, it is said, "The dragon appears in the field." The numerous yin lines of坤 all respond, so it is said, "It is beneficial to see the great man." Hui Dong's commentary (self-note from "three in the three realms of heaven, earth, and humanity" to "the image of the gentleman") states: This is Zheng Xuan's view. The other five lines of the乾卦 take the image of the dragon, but only the third line is called "the gentleman," because the Book of Changes divides the three realms of heaven, earth, and humanity. The third line belongs to the realm of humanity in the three realms. The "Discourse on the Changes" says: "The gentleman practices the four virtues of originality, prosperity, benefit, and constancy, hence the乾 is called originality, prosperity, benefit, and constancy." This shows that "the gentleman" refers to a person who possesses the virtue of the乾 and is in the position of humanity. Every time the text mentions "the gentleman," it refers to the nine three.

「惕懼」至「從古」。惕懼，鄭義也。《說文》曰：「夤，敬惕也。」《文言》曰：「雖危無咎。」故知厲為危也。「離為日，坤為夕」，虞翻義也。虞以陽息至三，二變成離，離為日。《繫》上曰：「剛柔者，晝夜之道也。」荀彼注云：「乾為晝，坤為夜。」《說文》：「夜從夕。」襄十三年《春秋傳》曰：「窀夕之事。」杜預注云：「夕，夜也。」是夕與夜同義，故知坤為夕也。

Hui Dong's commentary (self-note: "惕, fear; 冤, reverence" to "now follow the ancient text") says that interpreting "惕" as caution and fear is Zheng Xuan's view. The Shuowen Jiezi says: "Yin means reverence, caution, and vigilance." The Wenyan Zhuan says, "Although dangerous, there will be no mistake," indicating that "厉" should be interpreted as danger. "Li represents the sun, and Kun represents the evening" is Yu Fan's view: Yu Fan believed that when the yang energy reaches the third line, the second line changes to become Li, which then represents the sun. The Xi Ci Shang Wen says: "The interaction of yang and yin is the way of day and night." Xun Shuang commented there: "Qian represents day, and Kun represents night." The Shuowen Jiezi says the character "night" is composed of "xi." The Spring and Autumn Zuo Zhuan, Xianggong 13th year, mentions the term "zhun xi" (funeral matters at night), and Du Yu's commentary says: "Xi means night." Therefore, "xi" and "night" have the same meaning, so we know that Kun can symbolize dusk.

三與外體接，以乾接乾，故曰乾乾。荀氏謂承乾行乾，義亦同也。「坎為惕，乾為敬」，亦虞義也。《說卦》曰：「坎為加憂。」故為惕。乾為天，《周語》曰：「言敬必及天。」又曰：「象天能敬。」韋昭注云：「象天之敬，乾乾不息。」故知乾為敬也。寅本訓敬，今從夕，敬不衰於夕，夕惕之象。

Nine in the Third connects with the outer trigram, so乾 follows乾, hence the phrase '乾乾'. Xun Shuang interprets it as following and practicing the way of乾, which means the same thing. 'Kan represents vigilance, and乾 represents respect' is also Yu Fan's view. The 'Say of the Hexagrams' states 'Kan represents deep worry', so Kan can symbolize vigilance.乾 represents Heaven. The 'Guoyu · Zhouyu' says 'when talking about respect, one must mention Heaven', and also says 'emulating Heaven and being respectful', Wei Zhao's annotation states: 'emulating Heaven's respectful caution is to be strong and unceasing'. Thus, we know that乾 can symbolize respect. The character '寅' originally means respect. The character '夤' adds 'xi' on top of '寅', signifying that the heart of respect and caution does not diminish even at night, which precisely reflects the image of 'xi ti' (night vigilance).

俗本皆脫夤字。《說文》夕部引《易》曰：「夕惕若夤。」案許慎敘曰：「其偁《易》孟氏古文也。」是古文《易》有夤字。虞翻傳其家五世孟氏之學，以乾有夤敬之義，故其注《易》以乾為敬。俗本脫夤，今從古增入也。

The commonly circulated vulgar editions all omit the character 「夤」. The "Sayings of the Classic of Changes" cited under the "Xi" section of the "Shuo Wen Jie Zi" states it as "Xi Ti ruo Yin". According to Xu Shen's own account, "the version of the Classic of Changes cited in the book is the ancient text of the Meng clan." This shows that the ancient text of the Classic of Changes indeed contains the character 「夤」. Yu Fan's family had inherited the Meng clan's school of the Classic of Changes for five generations. Since the Qian trigram has the meaning of reverence and caution, he interpreted the Qian trigram as reverence. Since the vulgar editions have omitted 「夤」, now we restore it back into the text according to the ancient version.

「躍上」至「無咎」。此荀義也。躍，上，《廣雅》文。荀以地下稱淵，故謂淵為初。四本陰位，故非上躍居五者，即欲下居坤初。五與初皆陽之正位，故《文言》曰：「上下無常，非為邪也。」

Hui Dong's commentary (from the note "Jumping, meaning upward" to "Therefore, there is no blame") states that this is Xun Shuang's view. He interprets "jumping" as "upward," based on the Guangya. Xun Shuang believed that what is below the earth is called a deep pool, so he explains "deep pool" as the first line. The fourth line is originally a yin position, so here it is not moving upward to occupy the fifth position, but rather wanting to descend to the first position of the Kun hexagram. Both the fifth and first positions are proper positions for a yang line, so the Wenyan Zhuan says: "Going up and down without fixed direction, does not mean doing perverse things."

荀氏易例：乾在二者當上升坤五，在四者當下居坤初，在上者居坤三；坤在五者當下居乾二，在三者居乾上，在初者居乾四。如是則爻皆得位。乾四當居初，今以或躍為居五者，案乾寳注此經云：「初九，復也；九二，臨也；九三，泰也；九四，大壯也；九五，夬也；上九，乾也。坤初六，遘也；六二，也；六三，否也；六四，觀也；六五，剝也；上六，坤也。」消息十二卦實乾坤十二爻。九四體大壯，經云「藩泆不羸，壯於大轝之腹」，謂居五也，是四亦有居五之義矣。

Xun Shuang's interpretation of the Book of Changes is that the lines of the Qian trigram should move up to the fifth line of the Kun trigram when they are in the second position, and move down to the first line of the Kun trigram when they are in the fourth position, and those in the upper position should move down to the third line of the Kun trigram. Similarly, the lines of the Kun trigram should move down to the second line of the Qian trigram when they are in the fifth position, move up to the upper line of the Qian trigram when they are in the third position, and move up to the fourth line of the Qian trigram when they are in the first position. In this way, each line can return to its proper position. According to this principle, the fourth line of the Qian trigram should originally move down to the first position, but now it is interpreted as being in the fifth position, because Gan Bao's commentary on this passage says: "The initial line of Qian corresponds to the卦 of Fu, the second line corresponds to the卦 of Lin, the third line corresponds to the卦 of Tai, the fourth line corresponds to the卦 of Da Zhuang, the fifth line corresponds to the卦 of Guai, and the upper line corresponds to the卦 of Qian. The initial line of Kun corresponds to the卦 of Gou (i.e., Gou), the second line corresponds to the卦 of Dun (the text here is missing a name of a卦, which should be Dun), the third line corresponds to the卦 of Pi, the fourth line corresponds to the卦 of Guan, the fifth line corresponds to the卦 of Bo, and the upper line corresponds to the卦 of Kun." The twelve message trigrams are actually the twelve lines of Qian and Kun. The fourth line of Da Zhuang corresponds to the fifth position, as the text of the fourth line of Da Zhuang says, "The fence is broken but the ram's horn is not entangled, strength is in the axle of the big cart," which refers to being in the fifth position, showing that the fourth line also has the meaning of being in the fifth position.

「五體」至「是也」。《說文》釋龍曰：「春分而登天，秋分而潛淵。」陽息至五體夬，夬三月卦，龍已登天，故有是象。四變五體離，《說卦》曰：「離為雉。」郭璞《洞林》曰：「離為朱雀。」是離有飛鳥之象，故曰飛。五於三才為天道，又天位也，故飛龍在天。此上虞義也。二已變正應五，故利見大人。

Hui Dong's commentary (self-commentary from "five elements depart" to "this is what the world benefits from") says: The "Shuo Wen Jie Zi" explains the character "long" as meaning "on the spring equinox it ascends to heaven, on the autumn equinox it retreats to the deep abyss." When the yang energy reaches the fifth line, the hexagram becomes "Gua," which is the hexagram of the third month. At this time, the dragon has already ascended to heaven, hence the imagery. When the fourth line changes, the upper trigram where the fifth line is located becomes the trigram Li; the "Shuo Gua Zhuan" says "Li represents the pheasant," and Guo Pu's "Dong Lin" says "Li represents the Vermilion Bird," indicating that Li has the image of flying birds, hence the term "fly." The fifth line belongs to the heavenly aspect in the trinity of heaven, earth, and humanity, and it is also the position of the Son of Heaven, hence the phrase "a dragon flying in the heavens." All of this is according to Yu Fan's interpretation. The nine two has already changed to become correct and corresponds with the nine five, hence "it is advantageous to see a great man."

《乾鑿度》曰：「三畫已下為地，四畫已上為天，物感以動，類相應也。動於地之中則應於天之中，動於地之上則應於天之上。初以四，二以五，三以上，此之謂應。」是言六爻相應之義也。易重當位，其次為應，故彖傳言應者十有七卦。六十四卦之中，有當位而應者，有當位而不應者，有不當位而應者。若皆陰皆陽謂之敵應，《艮》彖傳所謂「上下敵應，不相與」也。

The "Qian Zao Du" says: "Three lines are associated with the earth, and four lines are associated with heaven. Things of the same kind respond to each other. If a movement occurs in the middle position of the earth, it corresponds to the middle position of heaven; if a movement occurs in the upper position of the earth, it corresponds to the upper position of heaven. The first line corresponds to the fourth line, the second line corresponds to the fifth line, and the third line corresponds to the top line. This is called 'response'." This explains the principle of correspondence among the six lines. The "Book of Changes" places great emphasis on the proper position of lines, and only then does it discuss correspondence. Therefore, the Commentary on the Judgment mentions "response" in seventeen hexagrams. Among the sixty-four hexagrams, there are those with proper position and correspondence, those with proper position but no correspondence, and those without proper position but with correspondence. If two corresponding lines are both yin or both yang, it is called "enemy response," which is what the Commentary on the Judgment of the "Gen" hexagram refers to when it says, "the upper and lower lines are in enemy response, and they do not relate to each other."

今乾二五敵應而稱利見大人者，乾用九，坤用六，乾二升五而應坤，坤五降二而應乾，故皆云利見大人。例諸他卦，或兩爻敵應，亦得變而相應也。虞氏以卦辭爻辭皆文王所作，庖犧德合乾五，故繋於九五。《冠禮記》曰：「天下無生而貴者。」《天問》曰：「登立為帝，孰道尚之。」王逸注云：「言伏羲始作八卦，修行道德，萬民登以為帝，誰開道而尚之。」是伏羲亦自下升也。

Now the second and fifth lines of the Qian hexagram are both yang, which normally would be opposing, yet it still says "favorable to see a great man." This is because Qian uses all nines and Kun uses all sixes: when the second line of Qian rises to the fifth position, it corresponds with Kun, and when the fifth line of Kun descends to the second position, it also corresponds with Qian. Therefore, both places say "favorable to see a great man." By the same reasoning, in other hexagrams, even if two lines are originally opposing, they can change positions and become corresponding. Yu Fan believed that both the hexagram statements and the line statements were composed by King Wen. Fuxi's virtue corresponds with the fifth line of Qian, so he is associated with the ninth line of the fifth position. The text in the Book of Rites, "The Ritual of the Adult Ceremony" says: "There is no one born into a position of honor." The "Heavenly Questions" from the Chu Ci asks: "Who guided and promoted him to become emperor?" Wang Yi's commentary says: "It refers to Fuxi who first created the eight trigrams, practiced virtue, and was elected emperor by the people. But who actually guided and promoted him?" This shows that Fuxi also rose from a lower position to a higher one.

象曰：「大人造也。」《文言》曰：「聖人作而萬物覩。」聖人作，是造作八卦也；萬物覩，是利見大人也。「窮高」至「有悔」。窮高曰忼，王肅義也。忼，高也，極也，故曰窮高。「陽極於上，當下之坤三」，此九家義也，荀氏例亦如此。九居上為失位，應在三，三陽爻，故無應。《繋》下曰：「易窮則變。」窮不知變，猶言知進而不知退也，故有悔。京房《見積算》曰：「靜為悔，發為貞。」是有悔為不變之義也。

The Image Commentary says: "A great person initiates something." The Discourse on the Literary Meaning says: "When the sage arises, all things look up to him." What is meant by "the sage initiates" is the creation of the eight trigrams. What is meant by "all things see" is the benefit of seeing the great person. Hui Dong's annotations (with his own note from "when the highest is reached it becomes 'kang'" to "therefore there is regret") say that calling the extreme of high as "kang" is Wang Su's view. "Kang" means high and extreme, so it is called "extreme high." A yang line reaching the highest position and reaching its extreme should descend to the third line of the坤卦, which is the view of the nine schools of the Yi. Xun Shuang's general practice is also like this. A yang line in the upper position is out of place, its responding line is at the third line, and the third line is also a yang line, so there is no correspondence. The Commentary of the Later Wings says, "When the Yi reaches its extreme, it must change." When reaching the extreme without knowing change, it is like knowing only to advance but not to retreat, hence there is regret. Jing Fang's "See Accumulated Calculations" says: "Stillness is called regret, and movement and change is called zhen." Thus, "there is regret" precisely means not knowing change.

「九六」至「用也」。《乾鑿度》曰：「陽動而進，變七之九；陰動而退，變八之六。」是九六者，爻之變也。坤，陰消之卦，起遘終乾，萬物成熟，成熟則給用，故坤為用。六畫稱爻，庖犧分天象為三才，以地兩之，為六畫。爻有剛柔，故發揮於剛柔而生爻。立地之道曰柔與剛，剛柔地道，故稱用也。

Hui Dong's commentary (self-commentary from "Nine and Six are the changes of the lines" to "Therefore it is called 'use'") states: The "Qianzuo Du" says: "When a yang line moves forward, it changes from seven to nine; when a yin line moves backward, it changes from eight to six." This shows that nine and six refer to the changes of the lines. The hexagram of Kun represents the decline of yin energy. It begins with "Gou" and ends with Kun (the original text says "end with Qian"), meaning that all things reach maturity here, and when things are mature, they can be used, so Kun symbolizes "use." The six lines are called "yao": Fuxi divided celestial phenomena into three categories, then doubled the earthly path, resulting in six lines. Yao are divided into yang and yin, so it is said that they are generated through the interaction of yang and yin. The "Shuogua Zhuan" says, "Establishing the earthly path is called yin and yang." Since yang and yin belong to the earthly path, they are called "use."

「群龍」至「首也」。乾六爻皆龍，故曰群龍，是群龍即六龍也。荀注九二見龍云：「見者，居其位。」是見群龍亦謂六龍皆居天位也。但龍之潛、見、惕、躍、飛、忼各有其時，是以彖傳、文言皆云「時乘六龍以御天」。六龍乘時御天，即用九見群龍之義也。乾為首，《說卦》文。乾位天德，坤下承之，故無首吉。《漢書》張竦曰：「德無首者襃不檢。」義與此同。引象傳者，明坤不可為天德之首也。

Hui Dong's commentary (self-commentary from "group of dragons, six dragons" to "heavenly virtue cannot be the leader" section): The six lines of the Qian hexagram all take the image of dragons, so it is called "group of dragons," indicating that "group of dragons" refers to the six dragons. Xu Shuang's commentary on line nine two says: "What is meant by 'seeing the dragon' is that the dragon is in its proper position." According to this, "seeing the group of dragons" means that the six dragons each occupy the heavenly position. However, the dragon's states of being hidden, appearing, alert, leaping, flying, and vigorous occur at different times, so the Commentary on the Judgment and the Discourse on the Image both say "according to time, riding the six dragons to govern the heavenly way." The six dragons riding according to time to govern heaven is exactly the meaning of "seeing the group of dragons" in the use of all nines. "Qian is the leader" comes from the Commentary on the Changes. Since Qian occupies the position of heavenly virtue and Kun is below supporting it, therefore "without a leader" it is auspicious. The words of Zhang Song recorded in the Han Shu say: "If virtue is great enough that no one can be ahead of it, then praising it does not follow the usual pattern." The meaning is similar. Hui Dong cites the Commentary on the Image to show that Kun cannot take the position of the leader of heavenly virtue.

樂出於易，易之乾坤十二爻即樂之十二律也。《周語》伶州鳩論六律六呂之義曰：「為之六間，以揚沈伏而黜散越也。元間大呂，助宣物也。」韋昭注云：「六間，六呂在陽律之間。呂，陰律，所以侶間陽律，成其功。十二月大呂，坤六四也。元，一也。陰繫於陽，以黃鐘為主，故曰元間，以陽為首，不名其初，臣歸功於上之義也。」是言陰無首以陽為首，與用九之義同也。

Music originates from the Yi Classic. In the Yi, the twelve lines of the trigrams Qian and Kun correspond to the twelve tones of music. The Guoyu · Zhou Yu records Ling Zhoujium's explanation of the six tones and six lü (the six yang tones and six yin tones): "Six intervals are established to promote the hidden and subdued energies and to eliminate scattered and chaotic sounds. The first interval is Da Lu, which helps to promote the growth of all things." Wei Zhao's commentary says: "The so-called six intervals are the six yin tones situated between the six yang tones. The yin tones belong to the yin category and are used to accompany and interleave with the yang tones, thus completing the function of the yang tones. The Da Lu of the twelfth month corresponds to the sixth line of the Kun trigram, the 'Yuan' refers to one. Yin depends on yang, with Huangzhong as the main tone, so it is called 'Yuan Jian,' meaning that yang is placed first, and it does not call itself the first — this is exactly the meaning of a minister attributing merit to the sovereign." This shows that yin does not take precedence but places yang first, which is the same as the meaning of "wu shou" (no beginning) in the use of nine.

坤元亨。注：乾流坤形，坤凝乾元，終亥出子，品物咸亨，故元亨。利牝馬之貞，君子有攸往。注：坤為牝，乾為馬，陰順於陽，故利牝馬之貞。乾來據坤，故君子有攸往。先迷後得主，句。利。注：坤為迷，消剝艮為迷復，故先迷。震為主，反剝為復，體震，故後得主。利。

The text says: "Kun, Yuan, Heng." Hui Dong's commentary: The qi of Qian spreads and Kun takes shape, and Kun gathers the original qi of Qian; the yin qi ends at Hai, and the yang qi begins at Zi, so all things become connected, hence it is said "Yuan Heng." The text says: "It is advantageous to be like a female horse that maintains constancy, the gentleman has a direction to go." Hui Dong's commentary: Kun symbolizes the female, Qian symbolizes the horse, and yin follows yang, hence it is said "advantageous to be like a female horse that maintains constancy"; Qian comes to occupy the position of Kun, hence "the gentleman has a direction to go." The text says: "First losing direction, then finding the master (Hui Dong marks a 'ju' character under the character 'zhu', indicating a pause here), advantageous." Hui Dong's commentary: Kun has the appearance of confusion, yin wanes until the hexagram of "Bao" and the upper trigram becomes Gen, which is the appearance of "confusion and returning," hence it is said "first losing direction"; Zhen symbolizes the master, and "Bao" reversed becomes "Fu," with the lower trigram being Zhen, hence it is said "then finding the master," thus it is advantageous.

西南得朋，東北喪朋，安貞吉。注：爻辰初在未，未，西南陰位，故得朋；四在丑，丑，東北陽位，故喪朋。地闢於丑，位在未，未沖丑為地，正承天之義也，故安貞吉。虞氏說此經以納甲，雲此易道陰陽消息大要也，謂陽月三日變而成震出庚，至月八日成兌見丁，庚西丁南，故西南得朋，謂二陽為朋，故兌君子以朋友講習，彖曰「乃與類行」。二十九日消乙入坤，滅藏於癸，乙東癸北，故東北喪朋，謂之以坤滅乾，坤為喪也。

The text says: Going to the southwest will gain friends, going to the northeast will lose friends, and maintaining a steady and upright position brings good fortune. Hui Dong's commentary states: According to the method of "Yao Chen," the first line of the Hexagram坤 (Kun) is at the position of "Wei," which is in the southwest, belonging to the yin position, hence gaining friends; the fourth line is at "Chou," which is in the northeast, belonging to the yang position, hence losing friends. The earth was created at "Chou," and the position of Kun is at "Wei," with "Wei" and "Chou" opposing each other but both belonging to the earth position. This precisely contains the meaning of serving heaven, hence "maintaining a steady and upright position brings good fortune." Yu Fan, on the other hand, explains this passage using "Najia" stem assignment, stating that this is the main outline of the yin and yang changes in the Book of Changes: On the evening of the third day of each month, the moon changes into the trigram Zhen (Thunder), emerging from the direction of Geng; by the eighth day, it becomes the trigram Dui (Lake), appearing in the direction of Ding. Geng is in the west, and Ding is in the south, hence "gaining friends in the southwest" — two yang lines of the same type gathering together is called "friends," so the trigram Dui says that the gentleman associates with friends for study and discussion, and the Commentary on the Judgment says "those with ability go together with their kind." By the twenty-ninth day, the moon's light disappears in the direction of Yi and enters the trigram Kun, becoming hidden and concealed in the direction of Gui; Yi is in the east, and Gui is in the north, hence "losing friends in the northeast" — this is called the trigram Kun extinguishing the trigram Qian, hence the trigram Kun has the image of loss.

疏：「乾流」至「元亨」。此虞義也。坤為形，乾之坤成坎，坎水流坤，是乾流坤形也。坤消乾自初，初為元，坤初六傳曰「陰始凝也」，是坤凝乾元也。坤終於亥，出乾初子，陰陽氣通，品物咸亨，故元亨。

Hui Dong's commentary (self-commentary from "Qian flows Kun shape" to "thus Yuan Heng" section): This is Yu Fan's view. Kun governs form, Qian entering Kun produces Kan, which represents water. Water flows over the land of Kun, which is called "Qian flows Kun shape." The dissolving of Kun over Qian starts from the first line, and the first line is precisely "Yuan." The "Image Commentary" of the first line of the Kun hexagram says "the yin energy begins to gather," which is called "Kun gathers Qian Yuan." The end of Kun's energy is at the亥 position, while the first line of Qian begins at the子 position. Thus, the energies of yin and yang are connected, and all things become harmonious, hence it is said "Yuan Heng."

「坤為」至「攸往」。坤為牝，九家《說卦》文；乾為馬，《說卦》文。坤，順也，故為牝；乾，健也，故為馬。以陰順陽，傳曰「柔順利貞」，故利牝馬之貞也。凡卦辭爻辭言利者，《繋》下云「變動以利言」，故乾坤變動皆言利也。君子謂陽，陰順於陽，陽來據坤初三五之位，故君子有攸往也。

Hui Dong's commentary (self-commentary from "Kun represents the female" to "the gentleman has a destination") states: "Kun represents the female" comes from the Nine Schools version of the "Commentary on the Changes," while "Qian represents the horse" comes from the current version of the "Commentary on the Changes." The virtue of Kun is flexibility and obedience, so it symbolizes the female; the virtue of Qian is strength and vigor, so it symbolizes the horse. Yin follows Yang, and the "Commentary on the Judgment" says "flexible and obedient, it is advantageous to maintain the correct path," hence the statement "advantageous for the female horse to be faithful." Whenever the hexagram statements or line statements mention "advantageous," the "Lower Commentary on the Changes" says "movement is discussed in terms of advantage and disadvantage," so whenever Qian or Kun has movement, it is said to be "advantageous." "The gentleman" refers to the yang line; Yin follows Yang, and the yang line occupies the first, third, and fifth positions, which are originally yang positions in the Kun hexagram, hence the statement "the gentleman has a destination."

「坤為」至「主利」。坤為迷，九家《說卦》文。剝上體艮，消剝為坤。剝上九曰「小人剝廬」，虞注云：「上變滅艮，坤陰迷亂，故小人剝廬。」是消剝為迷復，先迷之象也。《序卦》曰：「主器者莫若長子，故受之以震。」是震為主也。剝窮上反下為復，故反剝復初體震，震為主，故後得主乃利也。

Hui Dong's commentary (self-commentary from "Kun represents confusion" to "thus the later one gains mastery and is beneficial" section): "Kun represents confusion" comes from the Nine Schools version of the "Sayings on the Hexagrams." The upper trigram of the "Bao" hexagram is Gen, and when the yin energy is eliminated to the point of "Bao," it proceeds to become "Kun." The line statement of the upper ninth line of the "Bao" hexagram says, "The petty person loses his dwelling." Yu Fan commented: "When the upper line changes, the Gen image disappears, and the yin energy of Kun becomes confused, hence the petty person loses his dwelling." This shows that when yin energy is eliminated to the point of "Bao," it is exactly "confusion and return," which is the image of "first confusion." The "Sequence of Hexagrams" says: "There is no one more suitable than the eldest son to preside over the ancestral temple and sacrificial vessels, hence using the Zhen hexagram to follow after." This shows that Zhen represents mastery. When "Bao" reaches its upper line and reaches its extreme, it returns to the lower and becomes "Fu." Therefore, from "Bao" reversing to "Fu," the initial line of "Fu" forms the Zhen structure, with Zhen representing mastery, hence saying "the later one gains mastery" and it is beneficial.

「爻辰」至「故也」。此劉歆義，歆說詳《三統暦》也。爻辰者，謂乾坤十二爻所值之辰。乾貞於十一月子，間時而治六辰；坤貞於六月未，亦間時而治六辰。乾左行，坤右行。十一月子，乾初九也；十二月丑，坤六四也；正月寅，乾九二也；二月卯，坤六五也；三月辰，乾九三也；四月己，坤上六也；五月午，乾九四也；六月未，坤初六也；七月申，乾九五也；八月酉，坤六二也；九月戌，乾上九也；十月亥，坤六三也。二卦十二爻而朞一歲。鄭氏說易專用爻辰十二律，取法於此焉。

Hui Dong's commentary (from the note "the yao chen starts at Wei" to "therefore, the virtue of uprightness is auspicious") states that this is Liu Xin's view, which is detailed in the "San Tong Li." The term "yao chen" refers to the twelve earthly branches corresponding to the twelve lines of the Qian and Kun hexagrams. The Qian and Kun hexagrams together have twelve lines, which correspond exactly to the twelve earthly branches and the twelve months. The lines of the two hexagrams alternate and are arranged in sequence, so the Qian hexagram has six yang branches: Zi, Yin, Chen, Wu, Shen, and Xu, while the Kun hexagram has six yin branches: Chou, Mao, Si, Wei, You, and Hai. The Qian hexagram starts with the Zi branch of the eleventh month and governs every other branch, covering six branches in total. The Kun hexagram starts with the Wei branch of the sixth month and also governs every other branch, covering six branches in total. The Qian hexagram moves in a counterclockwise direction, while the Kun hexagram moves in a clockwise direction. The specific matching is as follows: the Zi branch of the eleventh month corresponds to the initial line of Qian (initial nine), the Chou branch of the twelfth month corresponds to the sixth line of Kun (six at the beginning), the Yin branch of the first month corresponds to the second line of Qian (nine in the second), the Mao branch of the second month corresponds to the fifth line of Kun (six in the fifth), the Chen branch of the third month corresponds to the third line of Qian (nine in the third), the Si branch of the fourth month corresponds to the top line of Kun (six at the top), the Wu branch of the fifth month corresponds to the fourth line of Qian (nine in the fourth), the Wei branch of the sixth month corresponds to the first line of Kun (six at the beginning), the Shen branch of the seventh month corresponds to the fifth line of Qian (nine in the fifth), the You branch of the eighth month corresponds to the second line of Kun (six in the second), the Xu branch of the ninth month corresponds to the top line of Qian (nine at the top), and the Hai branch of the tenth month corresponds to the third line of Kun (six in the third). The twelve lines of the two hexagrams cover the entire year. Zheng Xuan's interpretation of the Book of Changes specifically used the yao chen system to match the twelve tones, following exactly this method.

坤初六在未，未值西南，又坤之位，故得朋。六四在丑，丑值東北陽位，故喪朋。《漢書·天文志》曰：「東北，地事天位」是也。子為天正，丑為地正，初在未，四在丑，地正適其始，沖氣相通也。沖猶對也，《淮南·天文》曰：「其對為沖。」天開於子，地闢於丑，承天之義。漢楊震疏曰：「臣聞師言，坤者陰精，當安靜承陽。」彖傳注謂安於承天之正是也。

The initial line of the hexagram Kūn (Earth) is at position Wèi, which is in the Southwest direction, and this is also the original direction of the hexagram Kūn itself, so it is said to "gain companions." The fourth line is at position Chǒu, which is in the Northeast, a yang position, so it is said to "lose companions." The "Book of Han · Records of Astronomy" states, "The Northeast is the position where the earth serves the heavens," which is exactly this meaning. Zi is the first month of the heavens, and Chǒu is the first month of the earth; the initial line of Kūn is at Wèi, and the fourth line is at Chǒu, with Chǒu being the starting point of the earth. Therefore, the opposing energies are connected. "Chōng" means opposition. The "Huainanzi · Records of Astronomy" says, "Opposite positions are called chōng." The heavens begin with Zi, and the earth begins with Chǒu, which contains the meaning of serving the heavens. In his memorial to the court, the Han dynasty official Yang Zhen said, "I have heard from my teacher that Kūn is the essence of yin, which should be quiet and serve yang." The meaning of the commentary on the "Commentary on the Judgment" that it should be content to serve the correct position of the heavens is exactly this.

註釋得喪，正以坤之卦爻皆有承天之義，則此得朋喪朋當指坤之一卦而言，故用劉氏之說，獨以爻辰釋之。後世王弼、崔憬之徒，舍坤象之卦爻，廣求之於方位，尋其歸趣，雖強附於得喪，未見承天之象。今既刋落俗說，唯是易含萬象，所託多塗，虞氏說經獨見其大，故兼採之以廣其義。

Hui Dong's commentary explains "getting a companion" and "losing a companion" in this way precisely because the hexagram of坤 (Earth) contains the meaning of serving Heaven in every line and yao. Therefore, "getting a companion" and "losing a companion" should be understood in relation to the hexagram of坤 itself. Hence, he adopts Liu Xin's approach, using the yao chen exclusively to explain it. Later scholars such as Wang Bi and Cui Jing ignored the hexagram's lines and sought support from directions, investigating their implications. Although their interpretations could loosely connect with the concepts of gain and loss, they failed to recognize the image of serving Heaven. Now that these common interpretations have been discarded, the Book of Changes encompasses all things and has many ways of expressing its meaning. Yu Fan's interpretation of the classics alone grasps the main idea, so it is included here to expand its significance.

虞以易道在天，八卦三爻已括大要，故以得朋喪朋為陰陽消息之義。謂月三日之暮，震象出於庚方；至月八日，二陽成兌，見於丁方。生明於庚，上弦於丁，庚西丁南，故西南得朋，謂兌二陽同類為朋，又兩口對，有朋友講習之象，傳曰「乃與類行」是也。十五日乾體盈甲，六十日旦消乾成巽，在辛二十三日成艮，在丙二十九日消乙，入坤滅藏於癸，乙東癸北，故東北喪朋。坤消乾喪於乙，故坤為喪也。

Yu Fan believed that the principles of the Book of Changes are in Heaven, and the eight trigrams with their three lines already encompass the essential meaning. Therefore, he interpreted "gaining friends and losing friends" as the meaning of yin and yang waxing and waning. He said that on the evening of the third day of each month, the new moon appears as the trigram Zhen (Thunder) in the direction of Geng (West). By the eighth day, two yang lines form the trigram Dui (Lake), appearing in the direction of Ding (South). The moon begins to shine in Geng, and reaches the full moon in Ding. Geng belongs to the West, and Ding to the South, so it is said "gaining friends in the Southwest"—the trigram Dui has two yang lines of the same type, which is the meaning of friends. Dui also represents two mouths facing each other, symbolizing the image of friends discussing together. The Commentary on the Judgment says "those with ability go together with their kind," which is exactly this meaning. On the fifteenth day, the moon is full, and the trigram Qian (Heaven) is complete and receives the stem Geng. On the sixtieth day (the original text says "sixtieth day"), at dawn, the trigram Qian begins to wane and becomes Xun (Wind), receiving the stem Xin. On the twenty-third day, it becomes Gen (Mountain), receiving the stem Bing. On the twenty-ninth day, it wanes completely in the direction of Yi, entering Kun (Earth) and hiding in Gui. Yi belongs to the East, and Gui to the North, so it is said "losing friends in the Northeast." Kun wanes Qian and loses it in the direction of Yi, so Kun has the image of losing.

初六履霜堅冰至。注：初為履霜者，乾之命也。初當之乾四，履乾命令而成堅冰也。六二直方大，不習無不利。注：乾為直，坤為方，故曰直方。陽動直而大生焉，故曰大。習，重也，與襲通，《春秋傳》曰：「卜不襲吉。」三動坎為習，坤善六二，故不習無不利。

The first line says: "Having stepped on frost, firm ice is about to come." Hui Dong's commentary: The first line is called "stepping on frost" because it carries out the command from Qian. The first six originally should have moved to the fourth position of Qian, carrying out the command of Qian and thus forming firm ice. The second line says: "Straight, square, great, there is no need for repeated divination and nothing is unfavorable." Hui Dong's commentary: Qian symbolizes straightness, and Kun symbolizes squareness, hence "straight and square." When the yang energy moves, it becomes straight, hence "great." "Xí" means repetition, and it is related to "xí" (to repeat). When the third line moves, the lower trigram becomes Kan, which has the appearance of repeated actions. The virtue of Kun is most excellent at the second line, hence "without repetition, there is nothing unfavorable."

六三含章可貞，或從王事，無成有終。注：貞，正也。以陰包陽，故含章。三失位，發得正，故可貞。乾為王，坤為事，三之上終乾事，故或從王事，無成有終。《文言》曰：「地道無成而代有終也。」六四括囊，無咎無譽。注：括，結也。謂泰反成否，坤為囊，艮為手，巽為繩，故括囊。在外多咎，得位承五，繫於包桑，故無咎。陰在二多譽，今在四，故無譽。

The text says: Six in the Third, contains virtue and can maintain correctness; or it may engage in the affairs of the king, not claiming success, yet can attain a good ending. Hui Dong's commentary says: "Zhen" means correctness. A yin line encloses a yang line, so it is said "containing virtue." Six in the Third is out of position, but after movement it attains correctness, so it is said "can be correct." Heaven symbolizes the king, Earth symbolizes affairs, and Six in the Third moves to the upper position to complete the Heaven's affairs, so it is said "perhaps following the king's affairs, without success but with a good ending." The "Commentary of the Wenyan" says: "The way of Earth does not claim success, but merely completes the final stage on behalf of Heaven." The text says: Six in the Fourth, tightens the bag, neither having fault nor receiving praise. Hui Dong's commentary says: "Kuo" means to tie up. This refers to the transformation from the Trigram Tai to the Trigram Po: Earth symbolizes the bag, Mountain symbolizes the hand, and Wind symbolizes the rope, so it is said "tightening the bag." Although in the outer trigram, which is often prone to faults, Six in the Fourth is in the correct position and above supports Nine in the Fifth, like being tied to the roots of a mulberry grove, so there is no fault. A yin line in the second position is often praised, but now in the fourth position, so it is said "without praise."

六五黃裳元吉。注：坤為裳，黃，中之色；裳，下之飾。五當之乾二而居下中，故曰黃裳。降二承乾，陰陽位正，故元吉。上六龍戰于野，其血玄黃。注：消息坤在亥，亥乾之位，為其兼於陽也，故稱龍。戰者，接也。《說卦》曰：「戰乎乾。」乾西北之卦，稱野。陰陽相薄，故有是象。血以喻陰也。玄黃，天地之雜，言乾坤合居也。用六利永貞。注：永，長也。陰利居正承陽則永，故用六利永貞。京氏謂六偶承奇是也。

The text says: Six in the Fifth, yellow lower garment, great good fortune. Hui Dong's commentary: The trigram Kun symbolizes the lower garment; yellow is the central color, and the garment is the clothing for the lower body. Six in the Fifth should descend to the second position of Qian and reside in the middle of the lower trigram, hence it is called "yellow garment." It descends to the second position to support the yang of Qian, so yin and yang each occupy their proper positions, hence "great good fortune." The text says: Six at the Top, dragon fighting in the fields, blood flowing with black and yellow mixed. Hui Dong's commentary: According to the sequence of the five elements, Kun ends at Hai, and Hai is also the position of Qian. Since it contains yang, it is called "dragon." "Fighting" refers to meeting. The "Commentary on the Trigrams" says "fighting in Qian," and Qian is the trigram of Northwest, hence it is called "field." The interaction of yin and yang energies causes this image. Blood is used to symbolize yin; black and yellow are the colors of heaven and earth mixed, referring to the union of Qian and Kun. The text says: Using all sixes, it is beneficial to maintain constancy over a long time. Hui Dong's commentary: "Yong" means long. Yin lines are beneficial to reside in the proper position and support yang lines, thus being able to maintain constancy for a long time, hence it is said "using all sixes is beneficial for maintaining constancy." Jing Fang's idea that even numbers support odd numbers is the same principle.

疏：「初為」至「冰也」。爻例，初為足，為趾，為拇。履，踐也，足所以踐，故初為履霜者乾之命也。已下九家義也。乾居西北之地，為寒為冰，是霜與冰皆是乾氣加坤而成者，故曰霜者乾之命也。

Hui Dong's commentary (self-commentary from "initially stepping on frost" to "and then forming hard ice") states: According to the general principle of yao positions, the first line symbolizes the foot, the toe, and the big toe. "Lu" means to step on, and the foot is used for stepping, so the first line is called "stepping on frost," and this frost comes from the command of Qian. According to the Nine Schools of the Book of Changes: Qian resides in the northwest, governing cold and ice, indicating that both frost and ice are formed when the energy of Qian is added to Kun. Therefore, it is said that frost descends by the command of Qian.

劉向《鴻範五行傳》曰：「九月陰至五，通於天位，其卦為剝，剝落萬物，始大殺矣。」明陰從陽命，臣受君令而後殺也。若然，坤之消乾皆順乾命而成者，故《文言》曰「蓋言順也」。君子疾其末則正其本，易繫此爻，正以示戒。

Liu Xiang's "Hong Fan Wu Xing Zhuan" says: "In the ninth month, the yin energy rises to the fifth line, connecting with the Son of Heaven's position, forming the hexagram 'Bo', which causes the shedding of all things, thus bringing great severity and decline." This shows that yin follows the command of yang, and ministers carry out the orders of the sovereign before carrying out punishments. According to this, the decline of Kūn following Qian is accomplished in accordance with the command of Qian, so the "Wen Yan Zhuan" says, "This is probably referring to the concept of 'order' or 'propriety'." The virtuous man detests the consequences of disorder, so he must correct its root. The Zhou Yi attaches this line statement beneath the line "Chu Liu," precisely to serve as a warning.

「乾為」至「不利」。與乾旁通。「乾為直，坤為方」，九家《說卦》文。《繋》上曰「乾其動也直」，故乾為直。《文言》曰：「坤至靜而德方。」虞氏云「陰開為方」，故坤為方。陽動直而大生，陰動闢而廣生，方有廣義，故云直方大。

Hui Dong's commentary (self-commentary from "Qian represents straightness, Kun represents squareness" to "without practice, there is no advantage") states that Kun and Qian are "mutually complementary," meaning the two hexagrams have all six lines completely opposite in yin and yang, and are mutually internal and external. "Qian represents straightness, Kun represents squareness" comes from the Nine Schools version of the "Shuo Gua Zhuan." The "Xiyi Zhuan Shang Wen" says "when Qian is in motion, it is straight," so Qian symbolizes straightness. The "Wenyan Zhuan" says "Kun reaches the extreme of stillness and has a square and upright virtue," Yu Fan says "yin opens up and forms squareness," so Kun symbolizes squareness. Yang is active and straight, "greatness" arises from this; yin is active and opens up, "broadness" arises from this; squareness originally contains the meaning of breadth, so it is said "straight, square, and great."

習者，重襲，故與襲通。《春秋傳》者，哀十年傳文。《禮·表記》曰：「卜筮不相襲。」鄭注《大司徒》云：「故書襲為習。」是習為古文襲。習吉猶重吉也。《士喪禮》曰：「筮者三人。」《公羊傳》曰：「求吉之道三。」故經有初筮、原筮之文。不習者，言不煩再筮也。「坎為習」，虞義也。三可貞，動體坎，故坎為習。乾坤二卦唯九五六二為天地之中、陰陽之正，故云坤善六二，不習無不利也。

"Xí" means repetition and accumulation, so it is related to "xí" (to repeat). The cited text from the "Spring and Autumn Annals" is from the transmission of the tenth year of Duke Ai. The "Book of Rites · Bi Ji" states that "divination and yarrow stalk divination should not be repeated." Zheng Xuan's commentary on the "Rites of Zhou · Da Sizhu" says that "the ancient text used 'xí' to write 'xí'." This shows that "xí" is actually the ancient form of "xí," and "xí jí" means to repeat seeking good fortune. The "Rites of Zhou · Shi Sānguǐ" says that there are three people involved in divination, and the "Gongyang Zhuan" says that there are three ways to seek good fortune. Therefore, the classic text has expressions like "chū shī" (first divination) and "yuán shī" (original divination). "Bù xí" means there is no need to bother with a second divination. Yu Fan's view is that "Kan represents xí": the sixth line in the third position can change to become correct, and one movement of the lower trigram forms Kan, so Kan has the image of repeated practice. Among the trigrams of Qian and Kun, only the ninth line in the fifth position and the sixth line in the second position are in the center of heaven and earth and have the correct yin and yang, so it is said that the virtue of Kun is best with the sixth line in the second position, and "bù xí wú bù lì" (without repetition, there is no disadvantage).

「貞正」至「終也」。此虞義也。貞，正也，釋見上。荀氏云：「六三陽位，下有伏陽，故以陰包陽。」以六居三為失位，象曰「以時發」，故云發得正也。荀氏例坤三當之乾上，蓋六三九四不中不正，故彖象二傳言不當位者，獨詳於此二爻。三凡十四卦，四凡八卦也。

Hui Dong's commentary (from his own note "Zhen, meaning correct" to "no accomplishment but a finality") refers to Yu Fan's view. "Zhen" is interpreted as "correct," as explained earlier. Xun Shuang said: "The sixth line originally occupies a yang position, and there is another yang line hidden below, so it is a yang line enclosed by yin." A yin line in the third position is considered to be in an improper position. The "Image Commentary" says "waiting for the right time to act," so when it acts, it attains correctness. Following Xun Shuang's general approach, the third line of the hexagram of Kūn should be at the upper position of Qian. Generally, the sixth line and the ninth line of the fourth position are not in the center and are not in proper positions, so the "Commentary on the Judgment" and "Image Commentary" elaborate particularly on these two lines regarding improper positions. There are fourteen hexagrams discussing improper positions in the third line, and eight hexagrams discussing improper positions in the fourth line.

《說卦》曰：「乾為君。」又曰：「乾以君之。」故乾為王。坤致役，故為事。荀子曰：「主道知人，臣道知事。」坤，臣道，故坤為事。京房曰：「陰為事也。」三為三公，得從王事。乾立於巳，爻辰上六亦在巳，故云三之上終乾事，又引《文言》為證也。

The *Sayings on the Trigrams* states, "Qian represents the sovereign," and also says, "Qian governs all things with the principles of the sovereign," so Qian symbolizes the king. Kun governs labor and service, so it symbolizes "affairs." Xunzi says, "The way of the sovereign is to know people; the way of the minister is to know affairs." Since Kun represents the minister's path, it symbolizes affairs. Jing Fang says, "Yin is affairs." The third line's position corresponds to the Three Grand Ministers, which is sufficient to engage in the king's affairs. Qian is established at the巳 position, and according to the method of yao chen, the upper sixth line of Kun also corresponds to巳. Therefore, the third line moves to the upper position to conclude Qian's endeavors. Hui Dong also cites the *Discourses on the Hexagram* saying, "The way of the earth is without completion but has a final outcome," as supporting evidence.

「括結」至「無譽」。此虞義也。括，結，《廣雅》文。《說文》曰：「括，絜也。」絜與結古文通，故鄭注《大學》曰：「絜猶結也。」《禮·經解》曰：「絜靜精微，易教也。」絜者括絜，絜靜，坤也；精微，乾也。坤元絜靜，乾元精微，故云易教也。

Hui Dong's commentary (from the note "kuo, meaning to tie up" to "therefore there is no praise") states that this is Yu Fan's view. The term "kuo" is interpreted as "to tie up," based on the "Guangya." The "Shuowen Jiezi" says: "Kuo means to bind." "Xie" and "kuo" are interchangeable in ancient texts, so Zheng Xuan's commentary on the "Da Xue" says: "Xie is like tying up." The "Liji · Jingjie" says: "Pure and quiet, and subtle and refined, is the moral teaching of the Book of Changes." Here, "xie" refers to binding; purity and quietness belong to the Earth trigram, and subtlety and refinement belong to the Heaven trigram. The Earth trigram's original nature is purity and quietness, and the Heaven trigram's original nature is subtlety and refinement. Therefore, this is the moral teaching of the Book of Changes.

坤為囊，九家《說卦》文。坤《文言》曰：「天地閉，賢人隱。」虞彼注云：「謂四泰反成否，故賢人隱也。」艮為手，巽為繩，恆故為繩。以手持繩，括絜嚢口，故曰括嚢。四近五故多咎，五休否，繋於包桑，四居陰得位，上承九五，存不忘亡，故無咎也。《繋》下云：「二與四同功，二多譽，四多懼。」今在四，故無譽也。

"The phrase 'Kun represents a bag' comes from the Jiujia version of the 'Shu Gu Xuanchuan.' The 'Wenyan Zhuan' of the Kun hexagram says: 'Heaven and earth are closed off, and the virtuous retreat.' Yu Fan commented: 'This refers to the fourth line causing the Tai hexagram to reverse into the Po hexagram, hence the retreat of the virtuous.' Gen symbolizes the hand, and Xun symbolizes a rope—Xun is taken for its constant straightness, hence it is called a rope. Using the hand to hold the rope to tie up the bag's mouth, thus it is called 'kuan nang.' The fourth line approaches the ruler's position, hence it incurs many troubles; the nine in the fifth position can stop the closed-off trend, like securing it to the roots of a dense mulberry tree, thus being stable. The six in the fourth line, being yin in a yin position, is in the right place, and it supports the nine in the fifth above, remembering the danger of collapse even while alive, hence it has no faults. The 'Xici Xia Zhuan' says: 'The second and fourth lines have the same function; the second line is often praised, while the fourth line is often feared.' Now being in the fourth position, hence 'no praise.'"

「坤為」至「元吉」。九家《說卦》曰：「乾為衣，坤為裳。」「黃，中之色；裳，下之飾」，昭十二年《春秋傳》文。九家《說卦》曰：「坤為黃。」《文言》曰：「天玄而地黃。」案坤為土，《月令》曰：「中央土。」《郊特牲》曰：「黃者中也。」故云黃，中之色。經凡言黃者，皆謂陰爻居中也。毛萇《詩傳》曰：「上曰衣，下曰裳。」故云裳，下之飾。五居下中，故取象於黃裳也。降二承乾，陰陽位正，故元吉，謂承陽之吉也。

Hui Dong's commentary (self-commentary from "Kun represents the lower garment" to "thus great good fortune") states: The Nine Schools version of the "Discourse on the Hexagrams" says: "Qian represents the upper garment, Kun represents the lower garment." "Yellow is the central color, and the lower garment is the clothing for the lower body," which is the original text from the "Spring and Autumn Annals: Zuo Zhuan" of the twelfth year of Duke Zhao. The Nine Schools version of the "Discourse on the Hexagrams" says "Kun represents yellow," and the "Discourse on the Wings" says "the color of heaven is dark blue and the color of earth is yellow." According to the fact that Kun belongs to earth, the "Rites: Monthly Orders" says "the center belongs to earth," and the "Rites: Sacrificial Animals" says "yellow is the center," thus saying that yellow is the color of the center. Whenever the text refers to "yellow," it refers to the yin line occupying the central position. Mao Chang's "Poetry Commentary" says: "The clothing worn on the upper body is called 'yi,' and the clothing worn on the lower body is called 'shang.'" Thus, 'shang' refers to the clothing for the lower body. The line in the fifth position descends to the central position of the lower trigram, thus taking the image of the yellow lower garment. It descends to the second position to support the Qian yang line, with yin and yang each occupying their proper positions, thus "great good fortune" refers to the good fortune obtained by supporting the yang line.

「消息」至「居也」。坤消卦也，上六在亥，故曰消息在亥。《乾鑿度》曰：「陽始於亥，形於丑。」乾位在西北，陽祖微據始，是以乾位在亥。《文言》曰：「為其兼於陽也。」乾為龍，故稱龍。《說文》曰：「壬位北方，陰極陽生，易曰龍戰于野。」戰者，接也。上六行至亥與乾接，《說卦》「戰乎乾」，謂陰陽相薄也。

Hui Dong's commentary (from the note "the movement and stillness of the Earth in亥" to "speaking of the union of Heaven and Earth") states that the Earth trigram is one of the Yin trigrams, and the sixth line at the top is located in亥, so the sequence of movement and stillness reaches here at亥. The "Qian Zao Du" says: "Yang energy begins to arise in亥 and takes form in丑." The position of Heaven is in the Northwest, where the origin of Yang energy is weak and resides at the beginning, so Heaven is located in亥. The "Wen Yan Zhuan" says, "because it contains Yang." Heaven symbolizes the dragon, so here it is called "dragon." The "Shuo Wen Jie Zi" says: "The position of Ren is in the North, where Yin reaches its extreme and Yang begins to arise. The Book of Changes says, 'the dragon fights in the fields.' " Fighting" means meeting: when the sixth line moves to the position of亥, it meets with Heaven. The "Shuo Gua Zhuan" says, "fighting with Heaven," referring to the mutual pressure between Yin and Yang energies.

卦無傷象，王弼謂與陽戰而相傷，失之。毛萇《詩傳》曰：「郊外曰野。」乾位西北，故為野。血以喻陰，已下九家義也。《文言》曰：「猶未離其類也，故稱血。」焉知血以喻陰也。《乾鑿度》曰：「乾坤氣合戌亥。」故曰合居。

In the trigram images there is no meaning of injury. Wang Bi said that yin and yang fight and injure each other, which is a wrong interpretation. Mao Chang's "Poetry Transmission" says, "Outside the city is called wild." The trigram Qian is located in the northwest, so it symbolizes wild. "Blood is used as a metaphor for yin" is the view of the nine schools of the Book of Changes. The "Wenyan Transmission" says, "Because it has not yet separated from the category of yin, it is called 'blood.'" From this we can see that blood is indeed used as a metaphor for yin. The "Qianzuo Du" says, "The energies of Qian and Kun meet between Xu and Hai." Therefore, it is said "they dwell together."

「永長」至「是也」。永，長，《釋詁》文。《文言》曰：「坤道其順乎，承天而時行。」是坤之六爻皆當居陰位而承乾也。陰承陽則可長，故用六利永貞。京氏者，京房《律術》文。案《律術》一卷，虞翻為之注，其言曰：「陽以圓為形，其性動；陰以方為節，其性靜。動者數三，靜者數二，皆參天兩地，圓蓋方覆，六偶承奇之道」是也。《禮》《易》生人曰偶以承奇，易家用九用六即律家合辰合聲之法也。

Hui Dong's commentary (from his own note "Yong, meaning long" to "Jing Fang said that the six even numbers are supported by the odd ones") says: "Yong" is interpreted as "long," which comes from the Er Ya · Xigǔ. The Wenyan Zhuan says: "The principle of the earth is mainly the character of 'following,' supporting the heavens and moving in accordance with the seasons." This shows that the six lines of the earth trigram should all be in the yin position and support the heaven. Yin supporting yang can bring about longevity, hence the saying "using six is beneficial for enduring uprightness." The term "Jing Shi" refers to the text of Jing Fang's "Lv Shu." According to the "Lv Shu" which is one volume, Yu Fan once made annotations on it, saying: "Yang takes the shape of a circle, its nature being active; yin takes the shape of a square, its nature being still. The number of movement is three, and the number of stillness is two, both taking the meaning of 'three heaven and two earth.' The circle covers the square, which is the way of even numbers supporting odd numbers." This is exactly the meaning. The Li and Yi discuss human generation, also saying that even numbers support odd ones; the use of nine and six in the Yi is equivalent to the method of combining the celestial stems and sounds in the school of music.