Neo-Daoism is a name commonly given to various developments around the third and fourth centuries C.E. Some scholars suggest that there were two recognizable schools. One was called Secret Mystical Teaching (Xuan xue). According to some interpreters, an important theme was its emphasis on the quest for physical immortality. Earlier Daoist sources had spoken of immortality, but generally of the spiritual rather than the bodily sort. Neo-Daoism recommended exercises in breathing, diet, use of potions, elixirs, and talismans, and sexual activity reminiscent of Hindu and Buddhist Tantric practices. But perhaps more fundamental in this alchemy were intense meditative practices intended to reveal the Dao within the individual. Some scholars interpret Xuan xue as developing out of Confucian rather than Daoist thought. A major feature of the second school, known as Pure Conversation (Qing tan), is its attempts to blend aspects of Daoist, Confucian, and Buddhist thought. Among its proponents were the so-called Seven Sages of the Bamboo Grove, whose penchant for detached philosophical discourse and the cultivation of a Daoist aesthetic were among their hallmarks. On the basis of their reading of the Zhuang Zi and Dao De Jing, they developed a Neo-Daoist interpretation of the so-called Confucian classics. After the fifth century, Buddhist concepts infiltrated the movement to such a degree that Neo-Daoism gradually lost its distinctiveness and identity.