Simply keeping the mind clear and calm was, for many post-Tang Daoists, the path to eternal life and freedom. Through sheer serenity, practitioners believed they could attain immunity to hunger, eliminate sexual function, suspend breath and pulse, engage in astral travel, and command spirits and natural forces.In his meticulously researched study, Stephen Eskildsen examines how this perspective informed Daoist internal alchemists after the Tang dynasty (618–907), including prominent representatives of the Quanzhen tradition in the north and the Nanzong in the south. Drawing on a wide array of textual sources, he analyzes the teachings of figures like Qiu Chuji (1143–1227), Yin Zhiping (1169–1251), Zhang Boduan (ca. 984–1082), Bai Yuchan (1194– 1229), Li Daochun (fl. 1288–1292), Yu Yan (ca. 1253–1314), and Wu Shouyang (1574–after 1641), among others. These adepts emphasized passive, straightforward methods that they believed gave rise to spontaneous psychic, sensory, and physiological p