Yun-yen T'an-sheng (d. 841) was sweeping the ground when Reiyu (d. 853) came up and commented, "You are busily employed, are you not?" Yun-yen replied, "There is one who is not at all busily employed." To this Reiyu responded, "In that case you mean to say there is a second moon?" Yun-men then presented his broom and asked, "What number moon is this?"
Reiyu nodded and walked off. But when Hsuan-sha Shih-pei (834-908) heard the story, he said, "This is no other than a second moon!" (Transmission of the Lamp; Studies in Zen; Suzuki)
Before considering what all this bantering might specifically mean, it might be instructive to consider what this kind of bantering in general might mean. It reveals three Zen masters having fun with words. They are playfully probing one another's insight while irreverently bouncing a Zen metaphor back and forth to see how it might hold together. No one won; no one ever intended to do so. No truth was established; none was ever in the offing. The matters at stake might be as serious as death, but what's so serious about death? We do the mondo itself an injustice when we see it as other than they saw it themselves.
"Two moons" is Zen-speak for dualistic perception. There is only this one moon. The pursuit of another 'self' other than the one in pursuit would be to introduce a second moon. Another metaphor often used is that of adding a head, one upon the other. The experience to which Zen aspires is the integration of the totality of experience in this moment. It is being here now. It is not to be of two, or many, minds, but of single mind. When sitting, sit; when sweeping sweep. And yet, paradoxically, this is not a monadic, but an all-encompassing experience.
Thus, Yun-yen, had he given the 'correct' answer, would have agreed that he was busy. Instead, he threw a spanner in the works and apparently suggested that, though he was busy, there was another 'he' that was not. I could speculate on what he might have really meant (perhaps that nothing is really ever done), but the important thing is to realize he knew he was kicking the metaphor on down the road. This seems clear in his second response where he challenged Reiyu to give a number to the broom. He was declaring the metaphor intact, though he had only just carelessly broken it.
Suzuki, in his reply to the criticism of the historian Hu Shih, declared that both he and Hu were "descending into hell" by way of all their verbal sparring, yet he continued on because when transcendent you are free to participate in the mundane. When you know that words are not reality, you can use them to your heart's content. And turn them on their head when it suits you, too. The freedom to play is true freedom.
Then comes Hsuan-sha with his two cents: This is certainly two moons! Yes, indeed. And you make three! Ha, ha, ha. What do you say to a cup of tea?
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