What is the difference between Tai Chi and other qigongs?
Tai Chi has its own way of circulating qi. The qi should start at the dantian. From there it should move out to the extremities, and from there move back. Moreover, if the body moves, the qi moves, and if the qi move, the body moves. If I move part of me an inch, the qi should flow an inch. There are no movements where the body moves without the qi moving, and no movements where the qi moves without the body moving. Moreover the qi moves in the same direction as the physical movement, and in the same vicinity. This is quite different from other styles of qigong, where moving qi from, say your lungs, involves shaking your hand, or where you circulate qi using your mind.