What's the sound of one hand clapping?

Here is a poem by Zen Buddhist monk Ikkyu (1394-1181). He was eccentric, iconoclastic and a bit of a troublemaker. Oh, and a great poet.

You do this, you do that
You argue left, you argue right
You come down, you go up
This person says no, you say yes
Back and forth
You are happy
You are really happy.