Liuyao prediction, also known as "Najia Zhenfa", is the most sophisticated and systematic divination system in ancient China. To understand the Six Yao, one must first examine it within the larger framework of the entire Book of Changes.
"The Book of Changes" was originally a book of divination, which is clearly recorded in "Zhou Li Chunguan": "The three Yi methods of the Great Divination Palm: one is Lianshan, the second is Guizang, and the third is Zhouyi. Its hexagrams are all eight, and their differences are all sixty-four." The "jing hexagrams" here are the eight trigrams, and the "different hexagrams" are the sixty-four hexagrams. The six-yao prediction is based on the sixty-four hexagrams. Through a specific method of starting hexagrams, time, space, and personnel are included in the hexagrams for systematic deduction and analysis.
However, the six-yao method was not the original method of the Zhou Dynasty. The traditional method of making a hexagram in the Book of Changes is based on poaching the hexagrams, and "the changes are made by four camps, and eight out of ten changes are made into a hexagram" ("Xi Ci Zhuang"). Although this method is sacred and solemn, the operation is complicated, and the interpretation of the hexagrams and lines is relatively flexible, and there is a lack of unified judgment standards.
The emergence of Liu Yao Na Jia method was a major change in the history of Yi studies. It incorporates the Heavenly Stems and Earthly Branches into the hexagram
