The Gate "Yin and Yang"

In the taijitu, the circle itself represents a whole, while the black and white areas within it represent interacting parts or manifestations of the whole. The white area represents yang elements, and is generally depicted as rising on the left, while the dark (yin) area is shown descending on the right. The image is designed to give the appearance of movement. Each area also contains a large dot of a differing color at its fullest point to indicate how each will transform into the other.