Meditation in Movement
It is often said that the practice of tai chi is "meditation in movement". But what does it mean? In meditation you use some technique to absorb your troubled and restless mind for a while. It can be a word (a mantra), a sentence, or an object that you allow to fill you up. In the tai chi practice you concentrate on well-exercised, choreographed movements. Quite a complicated task, but repetitions of movements and practice, practice, practice makes it possible to accomplish a certain automatism where you are carried away by the flow of mostly slow movements.
The ideal is "wu wei", doing non-doing, acting easily and effortlessly as if by second nature, as if it just happens by itself. You can get in a kind of trance because you are taken by the slow flow. Music or sounds of nature may strengthen the feeling of flow. Like a poetic, rhythmical dance.
At the same time you are wide awake, focussed on clear observation of the changes of yin and yang, the details and intricacies of the movements. After years of training you still feel that you are becoming better and better, discovering something new about the movements and the way of the energy.
It is not the easiest way to meditate. We can even meditate just by looking at the clouds drifting across the sky. But the practice of tai chi involves both body and mind in a way that can make you feel like a whole human being improving as you go, gradually feeling at rest and full of energy all along.