無
mu
mu
Emptiness,none, no. In a koan by Master Joshu found in the Mumonkon (a collection of koans) it is reported that a student asked Joshu, "Does a dog have Buddha Nature or not?" Joshu replied "mu". Later another student asked Joshu, "Does a dog have Buddha Nature or not?" and the master replied "U...yes". For someone doing koan work with a teacher in the Rinzai tradition, this brings much confusion. To pass the koan with one's teacher, one must demonstrate an understanding which surpasses the rational mind.
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