According to the four images and eight diagrams, the plane coordinate system is called quadrant, and the spatial three-dimensional coordinate system is called six-hexagram limit.

The divination limit including X-axis positive semi-axis, Y-axis positive semi-axis and Z-axis positive semi-axis is called the first divination limit, which is determined counterclockwise above the xoy plane. The parts below the first, second, third and fourth hexagrams are called the fifth, sixth, seventh and eighth gossip respectively.