The so-called Taiji is the process of clarifying the universe from no pole to Taiji, to the birth of all things.
Taiji is the state of the universe before the heavens and the earth open up and before the chaos separates yin and yang.
The two yi refers to heaven and earth or yin and yang. Some martial artists have borrowed this term and applied it to boxing, such as martial artist Sun Lutang, who referred to movement as yang and static as yin, and collectively referred to movement and static as the two yin and two yi. On the “two yi”, synthesize the theories of successive generations of Yi school of thought, there are seven said: one for yin and yang, one for heaven and earth, one for odd and even, one for rigid and soft, one for xuanhuang, one for qiankun, one for spring and autumn. But usually refers to yin and yang.