Questions and Replies between Tang Taizong and Li Weigong

Questions and Replies between Emperor Taizong of Tang and Li Weigong (simplified Chinese: 唐太宗李卫公问对; traditional Chinese: 唐太宗李衛公問對; pinyin: Táng Tàizōng Lǐ Wèi Gōng Wèn Duì) is a dialogue between Emperor Taizong (599-649 AD) of the Tang Dynasty and Li Jing (571-649 AD), a prominent Tang general. It discusses matters of military strategy, and is considered to be one of the Seven Military Classics of China.

The content of Questions and Replies differs strongly from the other six Military Classics. The armies that existed by the time of the Tang dynasty consisted of infantry, crossbowmen, and cavalry. The use of the chariot had long since ceased to have any military application, and weapons were exclusively made from iron and steel. Large number of local, cohesive units provided a great degree of flexibility to large-scale deployments. Professional units were supplemented by disciplined and well-armed conscript forces. Weapons and unit sub-types were highly specialized. The recognition of the military value of speed and mobility was widespread, with flanking and other indirect maneuvers preferred over direct, frontal engagements.

The social and technological realities from which Questions and Replies was written were very different from the other six Military Classics. Rather than claiming to originate its own strategy, Questions and Replies frames itself as a survey of earlier, more widely recognized works, discussing their theories and contradictions according to the writer's own military experience. Because Li Jing was a historically successful general, the tactics and strategies discussed in Questions and Replies must be considered the theoretical product of actions tested and employed in battles critical to the establishment of the Tang dynasty, if it is indeed wholly or even partly the product of Li Jing's thoughts.

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