 From approximately the 7th century, the meditation practices outlined above were largely replaced by methods of contemplation and introspection (Kohn 2010). While their closeness to Buddhism is manifest, their roots also lie in early teachings and practices such as those described in the Neiye (Internal Training), dating from the second half of the 4th century BCE (Kirkland 2004: 39–52; Roth 1999; Graziani 2001), and in the above-mentioned speech of Guangcheng zi to the Yellow Emperor (Zhuangzi, ch. 11; Watson 1968: 118–20).