I. Foundations

Part 3: Eight Trigrams (Bagua)

3.3. Pre-Heavenly and Post-Heavenly Eight Trigrams numbers, and He Tu and Luo Shu Five-Element numbers

In I Ching divination, “trigram numbers” are not merely abstract theory. In this section, we will cover several number frameworks that you will repeatedly need in real judgments. These include the Pre-Heavenly Eight Trigrams numbers, the Post-Heavenly Eight Trigrams numbers, and the He Tu and Luo Shu Five-Element numbers.

These number systems matter because many questions in divination are, in essence, “taking numbers.” If the matter involves quantity, such as how many people, how much money, or how far, you can often derive the answer. This is done through these numerical correspondences rather than by vague interpretation.

In the forthcoming Studies on Ancient I Ching Divination Cases (Zhouyi Gushi Kao, 《周易古筮考》), written by Shang Binghe (尚秉和, circa 1880 to 1910 CE) and translated by Wanyan Xuan (完颜璇)1, there are many cases in which taking numbers is essential.

Case 64: Ming – Hu Sen and Yuan Qishan Divine a Lost Gold Cup – 23. Bo to 27. Yi

Ming dynasty. Hu Sen excelled at divination, often hitting marvelously true. Traveling in Jinling with his fellow townsman Yuan Qishan, the two lodged at the Temple of Divine Music. The supervisor Yao Yishan had by chance lost a gold cup and harshly blamed his apprentices. The two took pity and divined, obtaining “Bo to Yi” {first line change}.

At the southwest corner of the dwelling, dig five inches down and you will get it.”
In Bo the upper is Gen ☶, which has the image of an overturned cup; the lower is Kun ☷, which is earth; and Gen signifies stopping, so they knew the cup had stopped within the ground. Also, Kun’s position is the southwest, hence “dig at the southwest corner.” In the Nine Palaces [1] the number of Kun is five. Therefore, “dig five inches.” In 27.Yi, lines two through four and three through five both form mutual-body Kun. Counting down from 27.Yi’s Six-Five reaches the fifth place among Kun’s lines, hence “five inches.”[2]

[Annotation from the Translator (Wanyan Xuan)]
[1] “Nine Palaces numbers” refers to the Luo Shu Nine Palaces (Luo Shu magic square): the placement of 1 to 9 in a 3×3 grid. It links numbers, directions, trigrams, and the Five Elements for image-number work (for example, Flying Stars, Na Jia method, Qimen Dunjia (奇门遁甲).

Note: Some books say “Kun’s number is five,” meaning Earth’s base number is 5 in the He Tu & Luo Shu Five Element Numbers system. This does not refer to the Kun palace index in the Nine Palaces. In the Nine Palaces grid, Kun’s palace is 2.

1

Studies on Ancient I Ching Divination Cases is a rigorous and authoritative case-based classic in the field of I Ching divination. Featuring a total of 170 cases drawn primarily from Chinese historical records, this work compiles divinations recorded across thousands of years of Chinese history. Many of these influenced major political decisions of their time. It builds on the original 139-case edition of Studies on Ancient I Ching Divination Cases. This English edition adds further cases excerpted from Shang Binghe’s other writings to form a fuller and more comprehensive corpus.

Compiled and interpreted by the renowned I Ching scholar Shang Binghe, the book offers comprehensive readings that integrate hexagram texts, line statements, symbolic imagery, and Six Lines (Na Jia) method analysis. For readers unfamiliar with Chinese history, each case includes contextual background to illuminate the historical figures and events involved.

The collection also makes clear the historical influence of I Ching divination in China. It shows how rulers and high officials could employ it fluently to assess national affairs and military campaigns. Additionally, it shows how specific readings became reference points in later tradition.