C1618 Stair concealment(part ii)

What was Yang? Yang was heat, light, transformation, and qi! What was a sword? The sword was the blade, the sword was the edge, the change was the advance!

In Zhou Dunyi's Theory of Tai Chi, there is a paragraph that describes the endless and the tai chi, the tai chi that gives birth to the yang. The sword did not come out of the sheath, but its sharpness was restrained