TL;DR: Han dynasty Yijing studies (image-number) treated the Yijing as a symbolic system modeling the cosmos, using hexagrams to calculate calendar, climate and anomalies, so Meng Xi, Jiao Yanshou and Jing Fang built na jia, eight palaces, fei fu and gua qi. Wang Bi of Wei rejected that approach, commenting on the Yijing through meaning-principle, with the time and position of each line as the key, and his reading later overshadowed image-number in Confucian scholarship.
Where do Han dynasty I Ching studies and meaning-and-principle I Ching studies differ?
The two ways of reading the I Ching differ in what they take as the centre: image-and-number takes hexagrams, lines, heavenly stems and earthly branches, and seasonal qi as tools of calculation; meaning-and-principle takes the moral meaning, the times, and the position of the line as its focus. Han dynasty I Ching studies (often called Han Yi, the learning of image and number) flourished from the Western Han to the Eastern Han, with figures such as Meng Xi, Jiao Yanshou and Jing Fang. In the Wei dynasty, Wang Bi advocated discarding image and number and emphasising meaning and principle, opening a new way of reading.
This opposition is not a matter of "right or wrong" but of two different conceptions of what the I Ching essentially is. For the image-and-number school, the I Ching is a miniature model of the cosmos, usable to infer astronomy, calendrical method, climate and affairs of state. For Wang Bi, the I Ching is a book discussing human moral principle, to be read with philosophical thought rather than with calculation.
How did Meng Xi and Jiao Yanshou open the path of image and number?
Hui Dong (1696-1758), courtesy name Dingyu, second son of Hui Shiqi, followed his father's manner of learning and carefully examined Han scholarship in order to illuminate the meaning of the Classics[1].
Jiao Yanshou (courtesy name Gong) was a man of the state of Liang, served as magistrate of Xiaohuang county under Emperor Zhao of Han, and studied the I Ching under Meng Xi. Jing Fang is the author of a work of Western Han image-and-number I Ching studies, in which the 64 hexagrams are arranged in eight palaces, with the methods of shi-ying, najia and feifu[4]. Jiao Yanshou's Yilin comprises 16 scrolls; each hexagram transforms into 64 hexagrams, and the 64 hexagrams transform into a total of 4096 sayings, each saying a four-character verse[4].
The Yilin approach does not comment on each character of the I Ching but assigns to each pair of hexagrams a saying that judges a situation, like a table for looking up omens. This is material for later generations to use in divination, not a philosophical text.
How did Jing Fang systematise image and number into the eight palaces and najia?
Jing Fang (1st century BCE) is the one who raised the image and number of the I Ching to the level of a system: arranging the 64 hexagrams into eight palaces, assigning heavenly stems and earthly branches to each line, and establishing the relations of feifu, shi-ying, youhun and guihun. His Jingshi Yizhuan, still extant in the Complete Library of the Four Treasuries, is described as "a work of Western Han image-and-number I Ching studies: arranging the 64 hexagrams by eight palaces, the methods of shi-ying, najia, feifu".
According to the Siku Quanshu Zongmu Tiyao, Jing Fang was originally surnamed Li, gave himself the surname Jing, was a man of Dunqiu in Dongjun, studied the I Ching under Jiao Yanshou, served as Grand Administrator of Wei Commandery under Emperor Yuan of Han, and later died after being slandered. He left many works such as Jingshi Yizhuan in 3 scrolls, Zhouyi Zhangju in 10 scrolls, Zhouyi Tuogua in 7 scrolls, Zhouyi Yaozhan in 12 scrolls, Zhouyi Feihou in 9 scrolls...[4]. Today only the Yizhuan remains, but it is enough to show the massive scale of the image-and-number approach.
Jing Fang's eight-palace structure takes the eight pure hexagrams (Qian, Kan, Gen, Zhen, Xun, Li, Kun, Dui) as eight "palaces", each palace comprising one pure hexagram and seven hexagrams transformed from it in a fixed order, making up the 64 hexagrams. Each line in a hexagram is assigned a heavenly stem and earthly branch, called najia, and each hexagram has "shi" lines (representing the subject) and "ying" lines (representing the object), along with the concepts of feifu, youhun and guihun. This is precisely the foundation of the later Liu Yao method.
Where does najia take its stems and branches from, and what is it used for?
Najia is the method of assigning the ten heavenly stems and twelve earthly branches to the lines of a hexagram, based on the principle of yin and yang and the movement of the moon, in order to infer the generating and overcoming relations of the five phases. This is the way of tying the eight hexagrams to the eight positions of the moon within the month by stem, called "moon-body najia".
The najia method is not only for describing astronomy but also for calculating the generating and overcoming of the five phases among the lines, from which good and ill fortune are judged. For instance, a line belonging to Water overcomes a line belonging to Fire, a line belonging to Wood generates a line belonging to Fire, forming a complex web of relations. Jing Fang also established the concepts of "fu" (hidden line) and "fei" (manifest line), along with "youhun" and "guihun", to explain the transformations of hexagrams. These are the tools that later Liu Yao practitioners used widely.
Why did Wang Bi discard image and number to follow meaning and principle?
The Zhouyi Zhu comprises Wang Bi's commentary on the upper and lower classics and Han Kangbo's Eastern Jin commentary continuing the Xici, Shuogua, Xugua and Zagua, opening the path of meaning and principle: interpreting hexagrams by the meaning of the times and positions, discarding the image and number of the Han Confucians.
In his commentary on the Dun hexagram, Wang Bi wrote: "Dun means withdrawing from within to go outward... In the time of Dun, if one does not go, what disaster is there? But to be the tail of those who withdraw, disaster will come". He did not use stems and branches or the five phases but analysed the positions of the lines, the ying relations, and the meaning of the times. This commentary places its focus on "shi" (the moment, the circumstances) and "wei" (the position of the line in the hexagram), treating each line as a concrete moral situation.
Hui Dong followed his father's manner of learning, specialising in carefully examining Han scholarship to illuminate the meaning of the Classics. Zheng Xuan first studied under Jing Fang, then left to study under Fei Zhi, but Fei Zhi specialised in using Confucius's words to speak of the I Ching, and likewise could not master it without a teacher. That is why Wang Bi's I Ching flourished in the Jin and Tang dynasties[3]. Thus the enthronement of Wang Bi's meaning and principle was partly because Han image and number had lost its successors.
How do the two ways of reading differ within the same hexagram?
To see the difference clearly, one can compare how the two schools handle the same hexagram. The table below summarises the main points:
| Aspect | Han image and number (Meng Xi, Jing Fang) | Wang Bi's meaning and principle |
|---|---|---|
| Unit of analysis | Hexagrams and lines tied to stems and branches, the five phases, seasonal qi | Lines with position, time, ying relations |
| Purpose | Judging good and ill fortune, calamities and anomalies, affairs of state, calendrical method | Understanding moral principle, self-cultivation, conduct in the world |
| Tools | Najia, eight palaces, feifu, gua qi | Commentary on meaning, analysis of situations |
| Basis | Divinatory experience, the Han worldview | Confucian thought, Lao-Zhuang |
| Later influence | Liu Yao, feng shui, calendrical method | Orthodox Confucian learning, philosophical I Ching |
This table shows that the two schools differ not only in method but also in the purpose for which the I Ching is used. One is a tool of prediction, the other a philosophical book.
Why does Han image and number still exert influence today?
Though overshadowed by Wang Bi and the meaning-and-principle current in Confucian circles, Han image and number still survives in practical disciplines such as Liu Yao, feng shui and calendrical method, and became the foundation for many systems of folk divination. Jing Fang's Jingshi Yizhuan is regarded as the origin for the articles on Jing Fang, the eight palaces and najia in Liu Yao. The concepts of shi, ying, fei, fu, youhun and guihun are still used in the Liu Yao method today.
In Vietnam, books on feng shui and choosing days are also influenced by Han image and number, though their origin is not always consciously recognised. For instance, Tìm hiểu Cổ dịch Huyền không học by Hồ Kinh Quốc and colleagues (2001) discusses choosing days by seasonal qi and direction, with principles close to Han gua qi[2]. However, a distinction must be made: this is a later application, not Jing Fang's original text.
How do researchers today assess these two schools?
Some hold that Han image and number is the "correct" reading of the original I Ching, while Wang Bi's meaning and principle is a product of the Wei-Jin era that lost the "divinatory" quality of the I Ching. However, modern researchers do not regard this as a question of right or wrong, but as two different approaches reflecting two different eras. Hui Dong's Yi Han Xue (1696-1758) is a work recovering Han image and number, but Hui Dong himself also acknowledged that many parts had been lost[1].
Trần Trọng Kim notes the Han-learning school of the Qing dynasty, typically Hui Shiqi and Hui Dong; their manner of learning used past and present, far and near to determine right and wrong, and Hui Dong carefully examined Han scholarship to illuminate the meaning of the Classics. This shows that Han image and number was by no means entirely forgotten, but still had people seeking it out.
Nhật Nguyệt's suggestion: which way should one read the I Ching?
Nhật Nguyệt's suggestion: Today's reader need not choose a side. If you want to understand the I Ching as a philosophical and self-cultivating text, Wang Bi's meaning-and-principle approach is the shortest path. If you want to understand the basis of divination, day-choosing and feng shui, then you need to know Han image and number, especially Jing Fang, because that is the root of many practical systems. What matters is being aware of which way you are reading, and not confusing philosophical interpretation with prediction of fate.
Conclusion
Han dynasty I Ching studies, with Meng Xi, Jiao Yanshou and Jing Fang, built a vast system of image and number, turning the I Ching into a tool for modelling the cosmos and for prediction. Wang Bi of the Wei dynasty reversed the direction, bringing the I Ching back to moral principle and philosophy. These two ways of reading are not mutually exclusive but coexist, each meeting a different need of the reader. Understanding this difference helps us avoid both extreme superstition and the attitude that flatly denies the historical value of image and number.
