The I Ching is Chinese and the oldest of all the classical systems, from around 800 BCE. It is a great universal model and one of the oldest books in the world. It is based on simple binary (what our computers are built on) with 64 themes. In its original form it guides through the ways of nature, and provides wisdom for contemplation and insightful answers to questions. The 64 hexagrams is a useful tool for exploring something as complex as the spectrum of human consciousness. Looking at the spectrum of consciousness through 8 primary themes makes it simpler to see a larger perspective while appreciating the subtle essence of each.