Zen koan

A kōan (公案) (/ˈkoʊ.ɑːn/; Chinese: 公案; pinyin: gōng'àn, [kʊ́ŋ ân]; Korean: 공안 kong'an; Vietnamese: công án) is a story, dialogue, question, or statement, which is used in Zen practice to provoke the "great doubt" and test a student's progress in Zen practice.

The Japanese term kōan is the Sino-Japanese reading of the Chinese word gong'an (Chinese: ; pinyin: gōng'àn; Wade–Giles: kung-an; literally: "public case"). The term is a compound word, consisting of the characters "public; official; governmental; common; collective; fair; equitable" and "table; desk; (law) case; record; file; plan; proposal."

According to the Yuan Dynasty Zen master Zhongfeng Mingben (中峰明本 1263–1323), gōng'àn originated as an abbreviation of gōngfǔ zhī àndú (公府之案牘, Japanese kōfu no antoku—literally the andu "official correspondence; documents; files" of a gongfu "government post"), which referred to a "public record" or the "case records of a public law court" in Tang-dynasty China.Kōan/gong'an thus serves as a metaphor for principles of reality beyond the private opinion of one person, and a teacher may test the student's ability to recognize and understand that principle.

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