South hidden is a Zen master in Meiji era. One day, a university professor to ask him Chan, he only to treat tea. His tea into the guest's cup, until the cup is full, and then continue to inject. The professor looked at tea overflowing cup without rest, until it can no longer be silent, finally said: "have diffuse out, did not fall again!" "You look like this cup," Nan replied, "filled with your own opinions and ideas. You don't put your own mug empty, how to call me to say Buddhist to you?"