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Bi (Pi; disc)


Artwork Details

Bi (Pi; disc)
771 BCE - 256 BCE
cloudy light green nephrite with black and brown mottling
5 5/8 in x 5 5/8 in x 1/8 in (14.3 cm x 14.3 cm x 0.3 cm);5 5/8 in x 5 5/8 in x 1/8 in (14.3 cm x 14.3 cm x 0.3 cm);7 11/16 in x 7 11/16 in x 1 9/16 in (19.5 cm x 19.5 cm x 4 cm);5 1/2 in x 3 1/8 in x 1/8 in (14 cm x 8 cm x 0.3 cm);5 1/2 in x 2 1/2 in x 1/8 in (14 cm x 6.3 cm x 0.3 cm)
Museum purchase for the James Marshall Plumer Memorial Collection


The froms of the bi (circle) and cong (square) date back to the stone age in China but their original meaning, function, and names are unknown. In the succeeding Bronze Age cultures of the Shang (ca. 1600-1050 BCE) and early Zhou dynasty, cong and bi are rarely found. Unearthed in greater numbers in later Zhou sites, they gained importance in the following Han dynasty, where they were at the core of the earliest Chinese books on philosophy, cosmology, and metaphysics. The Zhou Li (Book of Rites), an ancient Chinese book, compiled by the Zhou dynasty and amended during the Han dynasty (206 BCE- 220 CE), describes the cong as a symbol of earth (square) and the bi as the symbol of heaven (circle).
(Label for UMMA Chinese Gallery Opening Rotation, March 2009)

Subject Matter:

The “bi” disk originated among China’s Liangzhu culture around 3,000-2,500 B.C.E. The function and meaning of these disks are unknown. As late as the Han dynasty (206 B.C.–A.D. 220), jade disks performed a ritual function in aristocratic burials, where they were placed above the head, below the feet, and on the chest of the deceased. They were also depicted on painted burial shrouds of the second century B.C. In these paintings two dragons thread their way through a jade disk, going on their way from the nether world to the celestial realm. This suggests that jade disks may have been intended to help the deceased's soul in its journey to heaven. Although it is not certain that the disks functioned in this way in Neolithic times, the enormous labor involved in perfecting their abstract shape and lustrous finish is striking testimony to the reverence accorded them and their importance as a ceremonial object.

Physical Description:

Large, flat disk made of gray and green jade with touches of black and brown with a hole in the center. Incised circle around outer edge of disk and around edge of interior hole.

Usage Rights:

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