Emblems and Numbers
This refers to the emblems and numbers used in divination. Emblems are cracks in baked tortoise shells, and numbers are inferred from stalks used in divination. Emblems and numbers are the basis of foretelling the future. In The Book of Changes, emblems are divination symbols and the things they represent, and numbers refer to the odd and even numbers of yin and yang and the numbers secured from the divination stalks. Some interpreters of The Book of Changes advocate using emblems and numbers to deduce the changes in all things in the universe.
The cracks in baked tortoise shells are emblems, and the divination stalks represent numbers. The appearance of things produces emblems; as emblems increase, so do numbers. (Zuo’s Commentary on The Spring and Autumn Annals)
The lines of a hexagram are signs of change; the odd and even numbers alternate and combine. By understanding the changes that occur in the lines of the hexagrams, we achieve an understanding of all the patterns in the world. When all possible numerical combinations have been exhausted, the images of things in the world have been determined. (The Book of Changes)