Zen - empty cup

Those who, to begin with, find Zen not only paradoxical and puzzling but annoying, even enraging, might profit from an old story of a certain learned man who came to a Zen master to inquire about this rare philosophy. The master politely invited his visitor to share a cup of ceremonial tea while they discoursed together. When the master had brewed the tea by the strict procedures of the tea ceremony, he began to pour the whisked green liquid into the visitor's cup and continued pouring until the cup had overflowed. Even then he went on pouring until the discomfited guest, unable longer to restrain himself, cried out in agitation, "Sir, my cup is already full, No more will go in." At once the master put down the teapot and remarked, "Like this cup, you are full of your own opinions and speculations. How can I show you Zen unless you first empty your cup?"

- NANCY WILSON ROSS, THE WORLD OF ZEN