What is the sound of one hand? The koan is Hakuin's, the Zen master who gave it to beginners, and he set it himself: two hands struck together make a sharp sound; one hand raised has neither sound nor scent. It is a question put to a student and meant to be sat with, not answered. The one hand is raised, not clapped; clapping is the English title's word, in print by 1935 and made famous by J. D. Salinger's epigraph, and the four characters say only the sound of one hand. 音声, a sutra word, is read onjō here. It sets a question, and the sitting with it is yours.
Hakuin Ekaku says, in his own tract of 1753, that he began setting the question five or six years earlier, after forty-five years of the older 無字 koan had brought only some dozens of students through; the sound-of-one-hand question is his own device, replacing the older koan rather than translating or adapting an earlier text.
We want you to be as happy with the meaning as you are with Master Takase's art. To learn more, visit Philology of 隻手の音声.