Wumen Huikai (simplified Chinese: 无门慧开; traditional Chinese: 無門慧開; pinyin: Wúmén Huìkāi; Wade-Giles: Wu-men Hui-k'ai; Japanese: Mumon Ekai) (1183–1260) is a Song period Chán (Japanese: Zen) master most famous as the compiler of and commentator on the 48-koan collection The Gateless Gate (Japanese: Mumonkan). Wumen was at that time the head monk of Longxiang (Wade-Giles: Lung-hsiang; Japanese: Ryusho) monastery.
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