Zhang Boduan

The Wuzhen pian (Chinese: 悟真篇; pinyin: Wùzhēn piān; Wade–Giles: Wu-chen p'ien; literally: "Folios on Awakening to Reality/Perfection") is a 1075 Daoist classic on Neidan-style internal alchemy. Its author Zhang Boduan (張伯端; 987?–1082) was a Song dynasty scholar of the Three teachings (Confucianism, Daoism, and Buddhism).

Zhang Boduan, or Zhang Ziyang 張紫陽, was a native of Tiantai 天臺 in present-day Zhejiang. After passing the Imperial examination, he began a career as a civil servant, but was banished to the frontier in Lingnan, where he served as a military commissioner. Zhang was later transferred to Guilin and Chengdu, where in 1069 he allegedly experienced sudden realization from a Daoist Master who instructed him in Neidan internal alchemy. Zhang wrote the Wuzhen pian, its appendices, and a few other texts, including the Jindan sibai zi 金丹四百字 "Four hundred words on the Golden Elixir" (tr. Davis and Chao 1940). He was additionally an authority on Chan Buddhism.

Biographical sources agree that Zhang Boduan died in 1082 CE during the reign of Emperor Shenzong of Song, but disagree whether he was born in 983, 984, or 987. Zhang was honorifically called Ziyang Zhenren 紫陽真人, ranking him as a Daoist zhenren 真人 "real/true/authentic person; perfected/authentic person" (the zhen in the Wuzhen pian), one rank higher than a xian 仙 "transcendent; immortal" in the celestial hierarchy.

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