During the late Eastern Han Dynasty, there were two scholars named Guan Ning and Hua Xin. They were very close friends and studied together since childhood. However, they had very different personalities. Guan Ning was diligent in his studies and had no desire for wealth or high positions. Hua Xin, on the other hand, was rather frivolous and greatly admired luxury and power.

Gradually, Guan Ning grew to disapprove of Hua Xin's values and conduct. One day, while they were sitting on a shared mat, Guan Ning took a knife and cut the mat into two halves, separating them. From that moment on, they sat apart and Guan Ning officially broke off their friendship.