The concept of the taiji ("supreme ultimate"), in contrast with wuji ("without ultimate"), appears in both Taoist and Confucian Chinese philosophy, where it represents the fusion or mother of yin and yang into a single ultimate, represented by the taijitu symbol . Tàijíquán theory and practice evolved in agreement with many Chinese philosophical principles, including those of Taoism and Confucianism.
Tai Chi emphasizes breathing and movement that are both flowing and graceful. Though its primary action is in the movement and breathing, this must all be carried out with particular mental focus during Tai Chi. This is why Tai Chi has often been referred to as meditation in motion.
In theory, Tai Chi directly affects qi - the "vital energy" or "life force" of the body - where proper flow of qi is said to be necessary to maintain health. During Tai Chi, this energy flows through the body through a network of 20 pathways (meridians from acupuncture). When these pathways are blocked, qi does not flow properly, and in theory, illness ensues. Tai Chi is thought to stimulate this flow of qi through the body and organs through its movements and breathing. Tai Chi can be seen as acupuncture from the inside.
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