TL;DR: Jing Fang was an I Ching scholar of the Western Han dynasty, credited by tradition with laying the foundation for the methods of najia, the eight palaces, the ruling and responding lines, and fei and fu in the Jingshi Yizhuan. He did not invent the I Ching; he turned the 64 hexagrams into a system that operates through the heavenly stems and earthly branches, the five elements and the six relations. This way of reading later became the backbone of Liu Yao divination and of many schools of I Ching divination.
Who was Jing Fang, and why is his name tied to najia?
Jing Fang (京房, courtesy name Junming) was an I Ching scholar of the Western Han dynasty, a native of Dunqiu in Dongjun commandery, who studied the I Ching under Jiao Yanshou (焦延壽) of the state of Liang. The Book of Han records that he was originally surnamed Li, was appointed by Emperor Yuan of Han as Grand Administrator of Wei Commandery in the second year of the Jianzhao era (37 BCE), and was later accused by the Palace Secretary Shixian and executed at the age of 41, meaning he was born around 77 BCE[3]. He is famous for a system that arranges the 64 hexagrams into eight palaces, attaching heavenly stems and earthly branches, the five phases, shi and ying, and fei and fu to each line. His name is tied to najia because that very system turned a hexagram from a pure diagram into an operating table that can be looked up, cross-checked against dates and hours, and used to judge affairs. In other words, Jing Fang did not rewrite the I Ching; he created a method of reading the I Ching with the tools of calendrical science and the five phases.
The book Jingshi Yizhuan (京氏易傳) has been transmitted under Jing Fang's name, originally in Han-era Chinese, and survives today on Wikisource[1]. This is a public-domain primary text, not a modern research work. So when we read it, we learn how Jing Fang's system was presented; we cannot treat every sentence in it as a verified historical fact.
At the opening of the Qian hexagram, the book says: "Qian, pure yang in operation, its image matches Heaven, it belongs to metal, with Kun as fei and fu, it occupies the shi"[1]. In a single sentence, the author has bound the hexagram to the five phases, to the fei-fu relation, and to the position of shi. That is exactly the mode of thought Jing Fang left behind: each hexagram is no longer an abstract diagram but a structure with properties, a position, and relations to other hexagrams.
How do the eight palaces and najia operate?
The core principle of the eight palaces is to take the eight pure hexagrams as eight palaces, then from each pure hexagram change one line at a time to generate the seven remaining hexagrams in that palace. Each palace consists of one pure hexagram and seven changed hexagrams; eight palaces make 64 hexagrams, both closed and ordered. That order lets the reader know which palace a hexagram belongs to, what the five phases of that palace are, and from there infer the generating and overcoming relations among the lines.
The summary section printed at the end of the book defines the concepts clearly. This section connects with the words of Jingyu (景迂, that is, Chao Shuozhi of the Song dynasty) and mentions Wang Bi, Guan Lu, and Shao Kangjie, so it is a summary by a Song-era person rather than by Jing Fang: "their advance and retreat follow the trigger, and the one that is the master of a hexagram is called shi; when triggers pair with one another, raising the second from the first, and it becomes the counterpart of the master, it is called ying"[1]. That is, the ruling line of a hexagram is called shi, and the line that corresponds to it is called ying. The book also says: "what shi occupies, and the four of yin and yang, is called fei; what yin and yang summon as their counterpart, yet never escapes its root, using the hidden and manifest to aid the divine clarity, is called fu"[1]. Fei is the manifest side, fu is the hidden side; the two sides always travel as a pair.
On how to place stems and branches on each line, the book records under the Qian hexagram: "Jia and Ren pair the inner and outer two images," with the note "Qian is the head of Heaven and Earth; Jia and Ren are divided into the Qian position"[1]. The lower volume lists all eight hexagrams: Qian and Kun pair with Jia, Yi, Ren, and Gui; Zhen and Xun pair with Geng and Xin; Kan and Li pair with Wu and Ji; Gen and Dui pair with Bing and Ding, with notes such as "Geng yang enters Zhen, Xin yin enters Xun"[1]. That is, yang hexagrams receive yang stems, yin hexagrams receive yin stems; only Qian and Kun each receive two stems, divided between the inner and outer trigrams.
The book also binds the five stars and the twenty-eight lunar mansions to the hexagrams. For example, under the Qian hexagram: "the five stars start from the position of Zhen star," "the Shen mansion starts from the position of Renxu"[1]. This is the astronomical layer of the system, showing that Jing Fang wanted to link the I Ching hexagrams to the sky and to calendrical science, not just to the five phases alone.
Table of core concepts
| Concept | Content according to the Jingshi Yizhuan | Role in judgment |
|---|---|---|
| Shi | The ruling line of the hexagram | Determines the central position of the affair |
| Ying | The line corresponding to shi | Determines the counterpart side, the circumstances |
| Fei | The manifest side of the hexagram | What is laid out before one's eyes |
| Fu | The side hidden beneath the hexagram | What is still latent, not yet revealed |
| Jian | Starting from shi, counted by month | The time marker of the hexagram |
| Ji | Counted by day, extending endlessly | The continuous cycle of movement |
| Najia | Assigning stems and branches to the six lines | Links the hexagram to calendrical science and the five phases |
| Five stars, twenty-eight mansions | Binding stars and constellations to the hexagram | The astronomical layer of the system |
Did Jing Fang invent najia?
There is not enough evidence to assert that Jing Fang was the first to conceive of najia. The Book of Han only records that his doctrine "flourished in disasters and anomalies," dividing the 64 hexagrams to take turns on duty, using wind, rain, heat, and cold as verification, and does not mention najia or the eight palaces[3]; najia, the eight palaces, shi and ying, and fei and fu are known through the Jingshi Yizhuan, a book transmitted under his name. The elements of stems and branches and the five phases already existed in Han-era thought; Jing Fang's contribution lies in fitting them together into a machine that could operate across all 64 hexagrams.
The I Ching tradition usually credits Jing Fang with founding the "Jing school" and holds that it was passed down through generations of students. However, the surviving primary text is only a small part of what ancient bibliographies record. The extant Jingshi Yizhuan has an appendix quoting Chao Gongwu of the Song dynasty, saying that most of the Jing school's books were lost, with only about a tenth remaining[1]. Therefore, any claim that Jing Fang "invented" or "fully transmitted" something should be read with caution.
In the summary section, the book also speaks of how to calculate numbers: "their empty number is twenty-eight, their full number is thirty-six"[1]. These numbers 28 and 36 appear repeatedly in the hexagrams, showing that Jing Fang's system has a fairly rigorous numerical layer, not merely image assignment. This is the point that makes the Jing school be seen as the "image and number" branch of I Ching studies, distinct from the "meaning and principle" branch inclined toward ethics and philosophy.
What traces did najia and the eight palaces leave in the art of Liu Yao?
The clearest traces are the method of placing stems and branches on the six lines, the method of determining shi and ying, and the use of the five phases and six relations to judge. These methods all originate from Jing Fang's system, then were supplemented and refined over many generations. The book Zengshan Buxi (增刪卜易) by Lord Yeh of the Qing dynasty, in the edition expanded by Li Wenhui, has chapters on the Eight Palaces, Huntian jiazi, and Shi and Ying that teach placing hexagrams according to that framework[2]. The Wikisource edition also prints at the front several formulas added by modern editors ("Najia ge," "Qiliu shen jue," "An shi ying yaoling"); these are not the words of Lord Yeh.
The "Najia ge" added by the editor summarizes the rule: "Qian inner Jia outer Ren, three sons Bing Wu Geng; Kun inner Yi outer Gui, three daughters Ding Ji Xin"[2]. Compared with the Jingshi Yizhuan, the phrasing is much more compact, but the principle is still to assign yang stems to yang hexagrams and yin stems to yin hexagrams. This is an example of how an ancient rule can be transmitted through many generations while keeping its core.
On shi and ying, the chapter on Shi and Ying lists the Qian palace as a model: the Qian hexagram has shi on the sixth line, Gou on the first line, Dun on the second, Pi on the third, Guan on the fourth, Bo on the fifth, Jin (a youhun hexagram) on the fourth, and Dayou (a guihun hexagram) retreating to the third; the line two positions away from the shi line is the ying line[2]. This order matches the eight palaces in the Jingshi Yizhuan: the pure hexagram, five hexagrams from the first shi to the fifth shi, then youhun and guihun. In other words, Qing-era Liu Yao still walks the road Jing Fang opened.
At what level should today's student read Jing Fang?
One should read Jing Fang at two levels: the textual level, to know what he actually wrote, and the technical level, to understand how the methods of placing hexagrams took shape. The textual level requires cross-checking the original Han-era Chinese, because translations can deviate. The technical level requires practicing placing hexagrams, because only when you yourself assign stems and branches to each line do you see the logic of the system.
The Jingshi Yizhuan also records a noteworthy sentence on the principle of movement: "rising and descending, reversing and returning, they cannot remain long in one place; a thousand changes and ten thousand transformations, hence it is called Yi; Yi means change" (升降反復，不能久處，千變萬化，故稱乎易。易者，變也), meaning that rising and falling, turning back and forth, not staying still for long, transforming in myriad ways, it is called Yi; Yi is change[1]. This sentence reminds us that in Jing Fang's system, hexagrams do not stand still but always move from one palace to another, from one shi to another, in a cycle that can be calculated. This is the difference between reading by image and number and reading by meaning and principle: one looks at the structure of movement, the other at moral teaching.
A suggestion from Nhật Nguyệt: if you are new to the I Ching, read the summary section of the Jingshi Yizhuan first, because that is where the Song-era editor summarizes the whole system. Only then read each hexagram to see how those rules are applied. For those already familiar with Liu Yao, reading Jing Fang helps you understand why each line carries a particular stem and branch, instead of merely memorizing the table of hexagram placement.
Why is Jing Fang still mentioned today?
Jing Fang is mentioned because he is the link between the classical I Ching and the systematic art of I Ching divination. Before him, the I Ching was mainly read as a philosophical and divinatory text. After him, the I Ching gained a set of tools for lookup, calculation, and judgment by date and hour. This is the turning point that made image-and-number I Ching studies a methodical tradition, not just oral teaching.
That appendix also records Jingyu's words that his edition had "characters reversed and erroneous" (文字顛倒舛訛), requiring correction by tracing image and number, and records that Liu Xiang once suspected Jing Fang of borrowing the name of the Meng family (劉向亦疑京托之孟氏)[1]. This reminds the reader that what we have today is only a part of a tradition that was once much larger. Therefore, when studying Jing Fang, one must distinguish between what the surviving text actually says and what later tradition adds.
By the Qing dynasty, Lord Yeh in Zengshan Buxi had systematized the methods of placing hexagrams and emphasized practicality[2]. The methods in the book (eight palaces, shi and ying, placing earthly branches on the six lines) all follow the framework of the Jing school. This is evidence that Jing Fang's influence lies not in the names mentioned, but in the rules that have become common standards.
In short, Jing Fang is regarded by tradition as the founder of najia and the eight palaces in image-and-number I Ching studies. His contribution is not in writing the I Ching, but in turning the I Ching into a system that can operate by stems and branches, the five phases, and calendrical science. That system is still alive today through Liu Yao and many other branches of I Ching divination.
