the Daodejing revolve around the nature of Dao, how to attain it and De, the inner power of Dao, as well as the idea of wei wu-wei. Dao is said to be ineffable and accomplishes great things through small, lowly, effortless and "feminine" (yin) ways (which are compared to the behavior of water). Ancient commentaries on the Daodejing are important texts in their own right. Perhaps the oldest one, the Heshang Gong commentary, was most likely written in the 2nd century CE. Other important commentaries include the one from Wang Bi and the Xiang'er commentary. Zhuangzi The Zhuangzi (Book of Master Zhuang, ), named after its supposed author Zhuang Zhou, is a highly influential composite text of multi-vocal writings from various sources and historical periods. The commentator and editor Guo Xiang (c. CE 300) helped establish the text as an important source for Daoist thought. One traditional view is that a sage called Zhuang zhou wrote the first seven chapters (the "inner chapters") and his students and related thinkers were responsible for the other parts (the outer and miscellaneous chapters). However, some modern scholars like Russell Kirkland argue that Guo Xiang is actually the creator of the 33-chapter Zhuangzi text and that there is no solid historical data for the existence of Zhuang zhou himself (other than the sparse and unreliable mentions in Sima Qian). The Zhuangzi uses anecdotes, parables and dialogues to express one of its main themes - avoiding cultural constructs and instead living in a spontaneous way aligned with the natural world. This way of living might be perceived as "useless" by most people who follow their own "common sense" and social and political rules, but this uselessness is actually a wiser alternative, since it is more in accord with reality. Chinese classics Daoism draws on numerous Chinese classics which are not themselves "Daoist" texts but remain important sources for Daoists. Perhaps the most important of these is the ancient divination text called the Yijing (circa 1150 BCE). The divination method in the Yijing and its associated concepts of yin and yang mapped into 64 "hexagrams" - combinations of the 8 trigrams - has influenced Daoism from its inception until today. Daoism also drew on other non-daoist Chinese classic texts including: The Mozi, which was later adopted as a Daoist text by Daoists (who also saw master Mo - Mozi - as a Daoist immortal and included