Actually it is not complete. should have the applique on each segment becoming something like this :
http://www.professionalfengshui.com/...09/i-ching.gif
The I Ching is a very ancient "divination" method. Actually to me is more like a philosophy. It is called The Book of changes. I have to say that Oriental culture is really focused on this topic. Nothing stays the same...even temples usually are rebuild and change very often ( of course it doesn't count the very ancient and historical ones).
The Tao actually has a slight different meaning: It symbolize Ying and Yang ( a dualism that can refer both in energy kind like female and male energy or good and evil and so on) . Basically it means that there is a balance between the opposite ( there is a little bit of one in the bigger part of the other)