Nan-in, a Zen master, received a university professor who had come to inquire about Zen. When Nan-in served tea, he poured his visitor’s cup full, and then kept on pouring. The professor watched the overflow until he no longer could restrain himself. “It is overfull. No more will go in!” “Like this cup,” Nan-in said, “you are full of your own opinions and speculations. How can I show you Zen unless you first empty your cup?” You can only be filled up with knowledge and rewarding experiences if you allow yourself to be empty.
