  The Laozi has been viewed in still other ways. For example, a Tang commentary by Wang Zhen, the Daodejing lunbing yaoyishu (Daozang no. 713), presented to Emperor Xianzong (r. 806–820) in 809, sees the text as a treatise on military strategy (Rand 1979–80; see also Wang Ming 1984 and Mukai 1994). The diversity of interpretation is truly remarkable (see Robinet 1998 for a typological analysis). The Daodejing was given considerable imperial attention, with no fewer than eight emperors having composed or at least commissioned a commentary on the work. These include Emperor Wu and Emperor Jianwen of the Liang dynasty, Xuanzong of the Tang, Huizong of the Song, and Taizu of the Ming dynasty (see Liu Cunren 1969 for a discussion of the last three).