I've found category theory to be an exciting, dynamic, and rather mind-bending discipline. When I first began studying it, though, it had a tragic shortcoming: unlike artificial intelligence, category theory didn't have any koans. So in late 1998, I did my clumsy best to correct this by writing the following.
Mac Lane constructed an adjunction between mathematics and religion. Mac Lane then asked the student, "Does category theory have Buddha?"
The student was enlightened.