The master summoned Nin before him and gave him a koan to contemplate: “What does the mind think about in-between thoughts?” and then he sent Nin away to meditate on the answer.
Nin meditated for a day then came back to the master and said, “Nothing, the mind does not think between thoughts, that’s a contradiction.”
“Wrong!” said the master, and he gave Nin a sharp smack across the nose and sent him off to try again.
This time Nin meditated on the koan for an entire week. Satisfied, he presented himself before the master and said, “Everything. Without the focusing lens of directed thought, the untethered mind reflects the universe.”
And the master gave him two smacks across the nose before sending him off again.
Nin meditated for a whole month before returning. “There is no answer,” said Nin.
“Wrong!” said the master, and Nin barely dodged a flurry of blows.
“Then what is the answer?” asked Nin.
“I’m not sure,” replied the master. “I haven’t really thought about it. This koan is for you, not me.”
“Then how will you know I’ve found the answer,” asked Nin, “if you don’t even know what the answer is?”
“You seek the truth that lies buried at the heart of world, yes?” asked the master. “How will you know if you’ve found the truth, if you don’t already know what the truth is?” He brought his palms together. “If you can resolve that question, you’ll have no need for koans at all.”