"A koan (pronounced /ko.an/) is a story, dialog, question, or statement in the history and lore of Chan (Zen) Buddhism, generally containing aspects that are inaccessible to rational understanding, yet that may be accessible to intuition."—Zen::Koans

"These koans, or parables, were translated into English from a book called the Shaseki-shu (Collection of Stone and Sand), written late in the thirteenth century by the Japanese Zen teacher Muju (the "non-dweller"), and from anecdotes of Zen monks taken from various books published in Japan around the turn of the 20th century."—Ashidakim Zen Koans