How many hexagrams are there in the sixty-four hexagrams of the Book of Changes?

Each hexagram has six hexagrams, and one * * * has sixty-four hexagrams.

2x2x2x2x2x2=64

Zhouyi was called the Book of Changes in ancient times. Legend has it that Zhou Wenwang (Ji Chang) was imprisoned by Shang Zhouwang. It was originally used to calculate fate. Because Shang Zhouwang was violent and ruthless, he served as Xibohou at that time. Later, he was chased as a captive of King Wen. He told fortune and escaped the disaster. Its principle is yin-yang theory. Taiji is divided into two instruments (yin and yang), two instruments give birth to four elephants (southeast and northwest), four are eight diagrams and sixty-four hexagrams. It is the Book of Changes that people see today. Its basic mathematical principle is split into two, which is called binary today. This has become the basis of modern advanced mathematics in the western world. This is also the principle behind the operation of contemporary computer networks. With the great development of contemporary science, Zhouyi fever has risen again. No matter how good the translation machine is, it can't compare with a human head.

Old couplet blog post; Zhouyi