Empress Lü Zhi
Sima Qian's (c. 91 BCE) "Records of the Grand Historian" (26) mentions "bigu" in connection with Zhang Liang (262-189 BCE), or the Marquis of Liu, who served as teacher and strategist for Emperor Gaozu of Han (r. 202-195 BCE). Zhang officially requested "to lay aside the affairs of this world, and join the Master of the Red Pine in immortal sport" (referring to Chisongzi "Master Red Pine", a legendary "xian" who, like Guiguzi, abstained from grains), and the emperor permitted it. Zhang Liang "set about practising dietary restrictions and breathing and stretching exercises to achieve levitation" (namely, "bigu", "daoyin", and "qingshen" "lightening the body"). After Gaozu died, Empress Lü Zhi urged Zhang to eat, saying, "Man's life in this world is as brief as the passing of a white colt glimpsed through a crack in the wall. Why should you punish yourself like this?" Zhang "had no other recourse but to listen to her advice and begin eating again. Eight years later he died." Based upon this account (which is also found in the "Lunheng"), Campany concludes that by the late 2nd and 1st centuries BCE, "the idea that some practitioners were abstaining from grains while practicing methods for consuming, directing, and cultivating "qi" as alternate nourishment was ubiquitous and commonplace."