Both Hands Clap
A monk asked Hakuin, "
What is the sound of one hand clapping?" Hakuin praised the question.
Later, a different monk asked,
"I have heard of your 'one hand' teaching.
But tell me, what is the sound of both hands clapping?" Hakuin immediately clapped his hands together once. "Listen to it," he said.
Reflection
Hakuin's clapping of two hands in response to 'the sound of both hands clapping' exposes the artificiality of the original koan. The monk who asks about both hands is still trapped in conceptual comparison; Hakuin simply demonstrates the sound, showing that the question was already answered by reality. The sound is always available – just listen.