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Yijing 易經 or Zhouyi 周易

Jul 24, 2010 © Ulrich Theobald

Zhouyi 周易 "Changes of the Zhou", also called Yijing 易經 "Classic of Changes", or, shortly, Yi 易 "The Changes", is one of the most important Confucian classics. It has not only influenced Confucian and especially Neo-Confucian thinking but is also deeply rooted in the Daoist tradition. It is so important that the discipline of yixue 易學 "Yijing studies" came into being.

The Yijing and Related Texts
易經 Yijing The "Book of Changes"
易緯 Yiwei Apocryphal Texts on the "Changes"
See also non-canonical books on divination (shushu 術數).

Types of Divination

The two most common ancient methods of divination were to produce cracks on the surface of turtle shells (guibu 龜卜, see oracle bones), and to count out milfoil (shi 蓍) stalks (zhanshi 占筮). Using a complex calculation method numbers were produced and transformed into two different types of lines (guaxiang 卦象), of which trigrams, and then hexagrams were composed. The Classic Zhouli 周禮, which describes the various state offices, speaks of three different types to handle the "changes" of auspicious and inauspicious aspects, namely the methods lianshan 連山 "connecting mountains" of the Xia people, guicang 歸藏 "storehouse" of the Shang, and the "changes" method of the Zhou people. The first two methods are unknown, except for a few surviving fragments recorded in Ma Guohan's 馬國翰 collectaneum Yuhanshanfang jiyi shu 玉函山房輯佚書. Some interpreters put forward the argument that the word zhou 周 in the title Zhouyi does not refer to the Zhou dynasty, but to a kind of "circle" that encompassed all sixty-four hexagrams.

Table 1. The Eight Trigrams (bagua 八卦) and their Signification of Natural Elements
Qian the Creative tian Heaven
Kun the Receptive di Earth
Kan the Perilous Pit shui Water
Li the Clinging huo Fire
Zhen Exciting Power lei Thunder
Gen Arresting Movement shan Mountain
Xun Gentle Penetration feng Wind
Dui Joy and Pleasure ze Swamp

Structure of the Text

The Yijing, as it is received, consists of two parts, the classic Zhouyi and a series of comments. The classic (the actual Yijing) was originally a divination book using a prognostication method by which 64 signs or symbols (gua 卦) were generated and interpreted. The 64 so-called hexagrams are each composed of two trigrams (see Table 2). There are eight trigrams in total, the famous bagua 八卦, that are also used in geomancy and other methods of divination. The trigrams consist of three lines that are either solid (the yang 陽, male or strong lines, yangyao 陽爻, represented by the number nine, jiu 九) or divided (the yin 陰, female or weak lines, yinyao 陰爻, represented by the number six, liu 六). The hexagrams are constructed from bottom to top. The hexagram Heng 恒 ䷟, for instance, is described as

Quotation 1. Description of the Composition of Hexagram Heng
Chu liu, jiu er, jiu san, jiu si, liu wu, shang liu.
初六、九二、九三、九四、六五、上六。
"Start: 6 [Yin or broken line], second: 9 [Yang or solid line], third: 9, fourth: 9, fifth: 6, top: 6." [counted from bottom to top]

Concerning the arrangement of the hexagrams, there are two traditions. The first is known from the received text, in which they are divided into two series beginning with Qian 乾 and Kun 坤. The second arrangement was found in the Zhouyi text discovered in the early Han period 漢 (206 BCE-220 CE) tomb of Mawangdui 馬王堆 near Changsha 長沙, Hunan, where the series also begins with Qian, but then continues with Pi 否 and ends with Yi 益. There are also other arrangements in various interpretive texts of the Han period, like Jiao Gan's 焦贛 Jiaoshi yilin 焦氏易林 or Jing Fang's 京房 Jingshi yizhuan 京氏易傳. The change of the particular lines (from 9 to 6 and vice versa; some lines being defined as unchanging), and with these, that of the whole hexagram, was believed to be subject to three factors, namely a natural conversion, human influence, and the supernatural influence of luck or misfortune.

Table 2. The Combined Trigrams or Hexagrams
N.B. Numbers indicate the resulting hexagrams listed in Table 4. Bold numbers identify hexagrams consisting of an identical set of trigrams.
Upper Trigram
Lower Trigram
qian kun kan li zhen gen xun dui
qian 1 11 5 14 34 26 9 43
kun 12 2 8 35 16 23 20 45
kan 6 7 29 64 40 4 59 47
li 13 36 63 30 55 22 37 49
zhen 25 24 3 21 51 27 42 17
gen 33 15 39 56 62 52 53 31
xun 44 46 48 50 32 18 57 28
dui 10 19 60 38 54 41 61 58

The Zhouyi, as the heart of the book, is divided into two parts, the first of which including the first 30 hexagrams, the second one the 34 others. The text on each hexagram is described in four parts: an illustration of the hexagram (guaxiang 卦象, i.e. the six-line diagram), its name (guaming 卦名), the corresponding dictum with an explanation of its meaning (guaci 卦辭), and an explanation of each of its particular lines (yaoci 爻辭). The dictum (guaci) includes direct statement about the auspicious (ji 吉), profitable (li 利), unlucky (jiu 咎) or non-auspicious (xiong 凶) character of a divination result. The guaci of the hexagram Qian and the yaoci of its first (lower) line are, for instance,

Quotation 2. Explanation of the Meaning of Hexagram Qian 乾 ䷀ and the Explanations of its Lines
Explanation of the Meaning (guaci 卦辭) of the Hexagram
元亨,利貞。 Originating (yuan) and penetrating (heng), advantageous (li) and firm (zhen.
Explanations of the Individual Lines (yaoci 爻辭)
初九、潛龍勿用。 In the first [line], Nine: The dragon lies hidden in the deep. It is not time for active doing.
九二:見龍在田,利見大人。 In the second [line], Nine: The dragon appearing in the field. It will be advantageous to meet with the great man.
九三:君子終日乾乾,夕惕若厲。无咎。 In the third [line], Nine: The superior man active and vigilant all the day, and in the evening still careful and apprehensive. [The position is] dangerous, but there will be no mistake.
九四:或躍在淵,无咎。 In the fourth [line], Nine: [The dragon looking] as if he were leaping up, but still in the deep. There will be no mistake.
九五:飛龍在天,利見大人。 In the fifth [line], Nine: The dragon on the wing in the sky. It will be advantageous to meet with the great man.
上九:亢龍,有悔。 In the sixth [line], Nine: The dragon exceeding the proper limits. There will be occasion for repentance.
用九:見群龍无首,吉。 [The lines of this hexagram] are [all] Nine. If the host of dragons [thus] appearing were to divest themselves of their heads, there would be good fortune. [Legge 1882: 57]

A small part of line explanations (yaoci) is not related to divination, but includes philosophical reflections.

The commenting part, the Yizhuan 易傳, is also called the "Great commentary" Yi dazhuan 易大傳 to discern it from later commentaries by students of the Zhouyi. It consists of seven parts, the first three of which being divided into two parts, so that they are called the "ten wings" (shiyi 十翼). These were in ancient times believed to have been written by Confucius 孔子, an assumption that was first doubted by the Song period 宋 (960-1279) scholar Ouyang Xiu 歐陽修 (1007-1072). The ten wings are:

Table 3. Commentaries on the "Changes" (Yizhuan 易傳), also called the "Ten Wings" (shiyi 十翼)
1-2 彖 (彖傳) Tuan (Tuanzhuan) A-B "Structure"
3-4 象 (象傳) Xiang (Xiangzhuan) A-B "Appearance"
5-6 繫辭 (繫辭傳) Xici (Xicizhuan) A-B "About the relationship of the Hexagrams"
7 文言 (文言傳) Wenyan (Wenyanzhuan) "About the characters"
8 說卦 (說卦傳) Shuogua (Shuoguazhuan) "Explaining the Hexagrams"
9 序卦 (序卦傳) Xugua (Xuguazhuan) "The order of the Hexagrams"
10 雜卦 Zagua "Miscellaneous sayings on the Hexagrams"

The Tuan commentary was written as an explanation of each hexagram and its lines. It includes Confucian interpretations of politics, social relations and personal cultivation. The xiang, divided into the "lesser" (xiaoxiang 小象) and the "greater appearance" (daxiang 大象) explains the wordings of this Classic, with a focus on the position of the ruler. The Xici commentary gives an overview of the position and the meaning of the Yijing in the world order and human life, and the meaning of Yin and Yang as factors creating a changing yet eternal universe. Because of its general meaning it is also called dazhuan 大傳 "Great commentary". The Wenyan commentary explains the general meaning of the first two hexagrams, Qian and Kun, which represent Heaven and Earth. The Shuogua explains how each hexagram could turn into another and how this change was related to the realms of Heaven, Earth and Man. It also explains which objects the hexagrams could be identified with. The Xugua is a mnemonic aid to the sequence of the hexagrams. The last commentary, Zagua, identifies similar or opposite hexagrams and highlights their relationship to each other. The tuan, xiang and wenyan commentaries are embedded in the texts about the individual hexagrams, and the xici, shuogua, xugua and zagua commentaries constitute individidual chapters in the second part of the book.

Quotation 3. Commentaries on the Hexagram Qian
Tuan 彖 Commentary
大哉「乾元」,萬物資始,乃統天。雲行雨施,品物流形。大明終始,六位時成。時乘六龍以御天。乾道變化,各正性命。保合大和,乃「利貞」。首出庶物,萬國咸寧。 Vast is the "great and originating [power]" indicated by Qian! All things owe to it their beginning: it contains all the meaning belonging to [the name] heaven. The clouds move and the rain is distributed; the various things appear in their developed forms. [The sages] grandly understand [the connexion between] the end and the beginning, and how [the indications of] the six lines [in the hexagram] are accomplished, [each] in its season. [Accordingly] they mount [the carriage] drawn by those six dragons at the proper times, and drive through the sky. The method of Qian is to change and transform, so that everything obtains its correct nature as appointed [by the mind of Heaven]; and [thereafter the conditions of] great harmony are preserved in union. The result is "what is advantageous, and correct and firm". [The sage] appears aloft, high above all things, and the myriad states all enjoy repose.
Xiang 象 Commentary
天行健,君子以自強不息。 Heaven, in its motion, [gives the idea of] strength. The superior man, in accordance with this, nerves himself to ceaseless activity.
1 「潛龍勿用」、陽在下也。 "The dragon lies hid in the deep"—the strong and undivided line's being in the lowest place.
2 「見龍在田」、德施普也。 "The dragon appears in the field"—the diffusion of virtuous influence has been wide.
3 「終日乾乾」、反復道也。 "Active and vigilant all the day"—the treading of the [proper] path over and over again.
4 「或躍在淵」、進「无咎」也。 "He seems to be leaping up, but is still in the deep"—if he advance, there will be no error.
5 「飛龍在天」、「大人」造也。 "The dragon is on the wing in the sky"—the great man rouses himself to his work.
6 「亢龍有悔」、盈不可久也。「用九」、天德不可為首也。 "The dragon exceeds the proper limits; there will be occasion for repentance"—a state of fulness, that is, should not be indulged in long.
「用九」,天德不可为首也。 "The same nine [undivided] is used" [in all the places of this hexagram], but the attribute of heaven [thereby denoted] should not [always] take the foremost place.
Wenyan 文言 Commentary
「元」者、善之長也,「亨」者、嘉之會也,《利》者、義之和也,「貞」者、事之幹也。 What is called "the great and originating" (yuan 元) is [in man] the first and chief quality of goodness; what is called "the penetrating" (heng 亨) is the assemblage of excellences; what is called "the advantageous" (li 利) is the harmony of all that is right; and what is called "the correct and firm" (zhen 貞) is the faculty of action.
君子體仁足以長人,嘉會足以合禮,利物足以和義,貞固足以幹事。君子行此四德者,故曰「乾、元、亨、利、貞」。 The superior man, embodying benevolence, is fit to preside over men; presenting the assemblage of excellences, he is fit to show in himself the union of all propriety; benefiting [all] creatures, he is fit to exhibit the harmony of all that is right; correct and firm, he is fit to manage [all] affairs. The fact that the superior man practises these four virtues justifies the application to him of the words "Qian represents what is great and originating, penetrating, advantageous, correct and firm." [Legge XXX]
「潛龍勿用」,何謂也?子曰:「龍、德而隱者也。不易乎世,不成乎名,遯世无悶,不見是而无悶。樂則行之,憂則違之,確乎其不可拔,潛龍也。」 What is the meaning of the words "The dragon lies hid - it is not the time for active doing?" The Master said: "There he is, with the powers of the dragon, and yet lying hid. The influence of the world would make no change in him; he would do nothing [merely] to secure his fame. He can live, withdrawn from the world, without regret; he can experience disapproval without trouble of mind. Rejoicing [in opportunity], he carries his principles into action; sorrowing [for want of opportunity], he keeps with them in retirement. Yes, he is not to be torn from his root [in himself]." This is "the dragon lying hid."
[...] [...]

History of the Text

The origin of the book is uncertain. Traditionally the invention of the trigrams is acribed to the mythical ruler Fu Xi 伏羲. King Wen 周文王 (r. beginning 11th cent. BCE) of the Zhou is said to have permuted the trigrams into hexagrams and was the first to arrange them in a certain pattern or sequence. A different sequence of the hexagrams was later ascribed to Fu Xi. The ten commentaries are ascribed to Confucius. The Han period scholar Ma Rong 馬融 (79–176) and the Tang period 唐 (618-907) commentator Kong Yingda 孔穎達 (574-648) thought the guaci had been compiled or at least developed by King Wen, the yaoci by his son, the Duke of Zhou 周公. All these statements are unbelievable, but what is sure is that different parts of the book were compiled over a long period of time by different groups of persons. Early parts must have been compiled in the late Western Zhou period 西周 (11th cent. - 770 BCE), and the final shape evolved during the Warring States 戰國 (5th cent. - 221 BCE).

Han period scholars divided up the Xiang and Wenyan commentaries and directly attached them to the corresponding hexagrams. This is the case in the commentaries by Zheng Xuan 鄭玄 (127-200) and Wang Bi 王弼 (226-249), the latter from the Three Kingdoms period 三國 (220-280).

During the Former Han period 前漢 (206 BCE-8 CE) there were four different traditions of the Zhouyi for which "professorships" (held by boshi 博士 "erudites") were created at the National University (taixue 太學): the lines of Shi Chou 施讎, Meng Xi 孟喜, Liangqiu He 梁丘賀, and Jing Fang 京房 (all living during the 1st cent. BCE). There was also a fifth tradition not taught at the National University, namely that of Fei Zhangweng 費長翁. The versions of Meng and Jing soon dominated over the others but were themselves overshadowed at the end of the Han period by those commented by Zheng Xuan and Wang Bi. The version of Shi Chou and Liangqiu He were lost during the Jin period 晉 (265-420).

Philosophical and Literary Meaning

Confucian influence plays a considerable role, but traits of Daoist philosophy, of correlative thinking and Yin-Yang theory can also be found. The sequence of the commentaries largely reflect its date of composition, the Tuan being the oldest part, the Xugua and Zagua the youngest.

The aristocracy of the Zhou period—and also that of their predecessors, the Shang dynasty 商 (17th-11th cent. BCE)—used to forecast a plethora of important political and social activities, like sacrifices, war, birth, voyages, marriages, or about natural disasters that threatened the harvest. Statements about such events or about internal quarrels at the court and among the nobility can also be found in the Zhouyi. Yet all these statements are expressed in a very concise way which is far from easy to understand and has therefore to be explained with the help of commentaries. The hexagram Kui 睽, for example, speaks about travelling, the hexagram Bi 賁 about marriage, and the hexagram Jing 井 about the problems governing a village. The world view of the Yijing is a bipolar one, in which Yin and Yang, the "great man" (daren 大人) and the "small man" (xiaoren 小人), fortune and misfortune, obtaining and loosing, increase and decrease, peace and stagnation, completion and lack, are opposed to each other and may in the course of time and under certain conditions transform into each other. This can also be seen in the statements about pairs hexagrams that are opposed to each other like Tai 泰 and Pi. In Tai it is said Xiao wang da lai 小往大來。 "The little gone and the great coming." (Legge 1882: 81), and in Pi: Da wang xiao lai 大往小來。 "The great gone and the little coming." (Legge 1882: 84.) Such a world view is not very far from the philosophy of the Daoist Zhuangzi 莊子 who stressed that a constant change and uncertainty befalls human life.

The text of the Zhouyi is written in very short lines or verses that often rhyme. A third of the old text can therefore be called a type of poetry. The rhyme patterns are not regular but often more composed according to need, like in the hexagram Guimei 歸妹, where it is said

Quotation 4.
女承筐,無實;Nü cheng kuang, wu shi;
士刲羊,無血。shi kui yang, wu xue.
The young lady bearing a basket, but without anything in it;
the gentleman slaughtering the sheep, but without blood flowing from it. (Legge 1882: 182)

or in the hexagram Dazhuang 大壯, which says that

Quotation 5.
羝羊觸藩,Diyang chu fan,
不能退,不能遂。bu neng tui, bu neng sui.
The ram butting against the fence,
and unable neither to retreat, or to advance. (Legge 1882: 130)

The hexagram Tun 屯 includes the verse

Quotation 6.
屯如,皤如,Tun ru bo ru,
白馬翰如;bai ma han ru,
匪寇,婚媾。fei kou, hun gou.
Distressed and obliged to return.
The horses of her chariot also seem to be retreating—
not by a spoiler, but by one who seeks her to be his wife. (Legge 1882: 62)

The first two examples refer to the life of shepherds, the third one to the preparation of a wedding. They can easily be compared with the "folk songs" in the Classic Shijing 詩經 "Book of Songs". Some paragraphs in the Zhouyi are comparable to the literary genre of fu 賦 "rhapsody" that found its early forerunners in descriptive texts, often of travels, as in the text to the hexagram Kui. The poetic genre of xing 興 "introducing atmosphere" (referring to the first verse of a poem) is represented by verses of the hexagram Jian 漸, like

Quotation 7.
鴻漸于陸,Hong jian yu lu,
夫征不復,fu zheng bu fu,
婦孕不育。fu yun bu yu.
Gradually advancing into the dry plains.
A husband who goes on an expedition from which he does not return,
and a wife who is pregnant but will not nourish her child. (Legge 1882: 179)

or such of the hexagram Mingyi 明夷:

Quotation 8.
明夷于飛,Mingyi yu fei,
垂其翼;chui qi yi,
君子于行,junzi yu xing,
三日不食。san ri bu shi.
Mingyi [darkening of the light] flying,
but with drooping wings;
When the superior man goes away,
he may be for three days without eating. (Legge 1882: 135)

The genre of bi 比 "Comparison" or "Parable" is to be found in the verses of the hexagram 履:

Quotation 9.
眇能視,Miao neng shi,
跛能履。bo neng lü,
履虎尾,lü hu wei,
咥人,凶。die. ren, xiong.
A one-eyed man can see;
a lame man can walk well;
one who treads on the trail of a tiger
is bitten. Ill fortune for man! (Legge 1882: 79)

From the viewpoint of linguistics, the text of the Zhouyi is very interesting for its wide use of grammatical particles, synonyms and rhyme binomes.

Commentaries

There are countless commentaries on and interpretations of the "Book of Changes". They can be divided into two great schools. The first one used the as a book for divination, in combination with phenomena of universe and nature. This tradition lived on in the Neo-Confucian interpretation of the Yijing by Liu Mu 劉牧 (1011-1064) and Shao Yong 邵雍 (1011-1077). Many Daoist masters were interested in the Yijing, like Chen Tuan 陳摶 (trad. 872-989) from the Tang period. Other Neo-Confucian scholars studying the Yijing were Hu Yuan 胡瑗 (993-1059), Cheng Yi 程頤 (1033-1107), Li Guang 李光 (1078-1159) and Yang Wanli 楊萬里 (1127-1206). From the Han period two such books are preserved, namely fragments of apocryphal texts subsumed under the name Yiwei 易緯 and Jing Fang's Jingshi yizhuan 京氏易傳. Many Qing period 清 (1644-1911) scholars interpreted these two writings, for example Hui Dong 惠棟 (1697-1758; Yi Han xue 易漢學, Zhouyi shu 周易述), Jiang Fan 江藩 (1761-1831; Zhouyi shubu 周易述補) or Zhang Huiyan 張惠言 (1761-1802; Zhouyi Yushi yi 周易虞氏義, Yiyi bielu 易義別錄).

The second school interpreted the Yijing on a philosophical background, making it part of the tradition of Confucian thought. This interpretation was introduced by Zheng Xuan and Wang Bi and continued by the Jin period scholar Han Kangbo 韓康伯 (332-380) and the Song period Neo-Confucians, in first place Cheng Yi (Chengshi yizhuan 程氏易傳). There were also commentators who are not easily classified as members of the one or the other of the two schools, like the Tang period scholars Kong Yingda (Zhouyi zhengyi 周易正義) and Li Dingzuo 李鼎祚 (8./9. cent.; Zhouyi jijie 周易集解), as well as the Great Southern Song period Neo-Confucian Zhu Xi 朱熹 (1130-1200; Zhouyi benyi 周易本義). Modern scholars have contributed new approaches to the study and interpretation of the , especially the connection between the book and conditions prevailing in history, like Guo Moruo 郭莫若 (1892-1978), Wen Yiduo 聞一多 (1899-1946), or Hu Pu'an 胡樸安 (1878-1947). The most important modern commentaries to the Yijing are Gao Heng's 高亨 (1900-1986) Zhouyi gujing jinzhu 周易古經今注, Li Jingchi's 李鏡池 (1902-1975) Zhouyi tongyi 周易通義 and Wen Yiduo's Zhouyi yizheng leizuan 周易義證類纂.

Table 4. The 64 Hexagrams (liushisi gua 六十四卦)
N.B. Translations According to Legge 1882.
First series, Shangjing 上經
1 Qian The Creative
2 Kun The Receptive,Resting in Firmness
3 Zhun (!) Initial Difficulty
4 Meng Youthful Folly, Obscurity
5 Xu Waiting, Nourishment
6 Song Conflict
7 Shi The Army, Group Action
8 Bi Holding Together, Union
9 小畜 Xiaoxu The Taming Force, Small Restraint
10 Treading Carefully
11 Tai Peace
12 Pi (!) Stagnation
13 同人 Tongren Union of Men
14 大有 Dayou Great Possession, Abundance
15 Qian Modesty
16 Yu Harmony, Joy, Enthusiasm
17 Sui Following
18 Gu Arresting Decay
19 Lin Approach, Advance
20 Guan Contemplation
21 噬嗑 Shihe Biting Through
22 Bi Adornment
23 Bo Falling Apart
24 Fu Returning
25 無妄 Wuwang Correctness, Innocence
26 大畜 Daxu The Great Taming Force
27 Yi Correctness, Innocence
28 大過 Daguo Excess
29 Kan The Perilous Pit
30 Li The Clinging; Brightness
Second series, Xiajing 下經
31 Xian Influence
32 Heng Preseverance, Duration
33 Dun Retreat
34 大壯 Dazhuang The Power of the Great
35 Jin Progress
36 明夷 Mingyi Darkening of the Light
37 家人 Jiaren The Family
38 Kui Disunion, Mutual Alienation
39 Jian Arresting Movement
40 Jie Removing Obstacles
41 Sun Decrease
42 Yi Increase
43 Guai Removing Obstruction, Breaking Through
44 Gou Encountring
45 Cui Gathering Together
46 Sheng Ascending
47 Kun Oppression
48 Jing A Well
49 Ge Revolution
50 Ding The Cauldron
51 Zhen Thunder, Exciting Power
52 Gen Mountain, Arresting Movement
53 Jian Gradual Progress, Growth
54 歸妹 Guimei The Marrying Maiden; Propriety
55 Feng Abundance, Prosperity
56 Travelling Stranger
57 Xun Gentle Penetration
58 Dui Joy, Pleasure
59 Huan Dispersion
60 Jie Regulation, Restraining
61 中孚 Zhongfu Inmost Sincerity
62 小過 Xiaoguo Small Excesses
63 既濟 Jiji Completion
64 ䷿ 未濟 Weiji Before Completion

Sources:
Cao Chuji 曹礎基 (1986), "Zhouyi 周易", in Zhongguo da baike quanshu 中國大百科全書, Zhongguo wenxue 中國文學 (Beijing/Shanghai: Zhongguo da baike quanshu chubanshe), Vol. 2, pp. 1297-1298.
Zhong Zhaopeng 鍾肇鵬 (1992), "Zhouyi 周易", in Zhongguo da baike quanshu 中國大百科全書, Zhongguo lishi 中國歷史 (Beijing/Shanghai: Zhongguo da baike quanshu chubanshe), Vol. 3, pp. 1607-1608.
Zhu Bokun 朱伯崑 (1987), "Yijing 易經", in Zhongguo da baike quanshu 中國大百科全書, Zhexue 哲學 (Beijing/Shanghai: Zhongguo da baike quanshu chubanshe), Vol. 2, pp. 1091-1092.
Translations according to James Legge (1882), The Sacred Books of China: the Texts of Confucianism - the Yi King (Oxford: Clarendon).
Further reading:
Edward Hacker, Steve Moore, Lorraine Patsco, ed. I Ching: An Annotated Bibliography (New York/London: Routledge, 2002).
Nylan, Michael (2001). The Five "Confucian" Classics (New Haven: Yale University Press).