Tai-chi can be treated as the driving force of the universe, which generates two poles (Yang, Yin), then evolving the four phases (sky, earth, men, and matter), which then produce the eight sections (sky, earth, men, matter, time, space, material and spirit). They give rise to all kinds of activities in the earth.
Tai Chi is a centuries old Chinese discipline for health, relaxation, balance, flexibility, strength, meditation, self-defense and self-cultivation. It improves circulation, balance, coordination, and helps relax and strengthen the muscular and nervous systems.
The stretching movements make the body limber, tone up muscles, and help release tension. As a meditation, Tai Chi is a way of harmonizing body and mind dynamically. Tai Chi is referred to as moving meditation. The mind should be as still as if you are in sitting meditation, but you should still be able to actively circulate your Chi. You should look centered and calm from the outside, but with in is like a raging sea. When you are attacked you should still be calm and aware. When you have learned this you are able to respond in a calm and natural way to an opponents moves. Tai Chi is change and you should follow and respond naturally to the opponents every subtle move and situation.