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Lingqijing (or Ling Ch'i Ching; 靈棋經 lit. "Classic of the Divine Chess") is a Chinese book of divination. It is not known when, nor by whom, it was written, though a legend has spread that strategist Zhang Liang received the book from Huang Shigong (黃石公), a semi-mythological figure in Chinese history. The first commented edition of the work appeared in the Jin Dynasty.
Twelve Xiangqi pieces are used; each piece is a disc with a character on one side, and the other side unmarked. Four have the character for "up" (上, pronounced shang), four have the character for "middle" (中, zhong), and four have the character for "down" (下, xia), representing respectively the Three Realms: Heaven (天, tian), Humanity (人, ren), and Earth (地, di).
These pieces are cast onto a surface, and the text of the Lingqijing the resulting combination is in for what fortune the combination means.
The text of the Lingqijing has an entry for all 125 combinations (i.e., three kinds of pieces, times the five possibilities for each kind: one through four pieces landing face up, or none).
Notes
As can be seen in entry "Xiangqi", none of the characters 下, 中, or 上 occur actually as characters on Xiangqi pieces. The pieces for Lingqijing look like Xiangqi pieces, except for bearing these special characters.
See also
I Ching - the most famous Chinese oracle, much more complex than the Lingqijing