The Art of War by active 6th century B.C. Sunzi

Kung-wu says that he was impelled to write a new commentary on Sun Tzŭ because Ts’ao Kung’s on the one hand was too obscure and subtle, and that of Tu Mu on the other too long-winded and diffuse. Ou-yang Hsiu, writing in the middle of the 11th century, calls Ts’ao Kung, Tu Mu and Ch’en Hao the three chief commentators on Sun Tzŭ, and observes that Ch’en Hao is continually attacking Tu Mu’s shortcomings. His commentary, though not lacking in merit, must rank below those of his predecessors.