Nansen kills the cat

Here is a koan that I quite like called Nansen kills the cat from the Mumonkan or The Gateless Gate. I have taken it from the dewdrop.org.

Once the monks of the eastern and western Zen halls in Master Nansen’s temple were quarrelling about a cat. Nansen held up the cat and said, “You monks! If one of you can say a word, I will spare the cat. If you can’t say anything, I will put it to the sword.” No one could answer, so Nansen finally slew it. In the evening when Joshu returned, Nansen told him what had happened. Joshu thereupon took off his sandals, put them on his head, and walked off. Nansen said, “If you had been there, I could have spared the cat.”