Six Secret Teachings, Dragon Teaching — The Secret Letter六韜 陰書
Wujing Qishu (The Seven Military Classics) — the six besides the Sunzi 武經七書 · Ascribed to Jiang Taigong · ascribed to Huang Shigong · Wei Liao · Wu Qi · Sima Rangju · Li Jing · Warring States to Tang (4th century BC to 7th century AD) · 1 passages · 132 Chinese characters · reading time 0.5 min
Wujing Qishu (The Seven Military Classics) — the six besides the Sunzi Six Secret Teachings The six that remain when the Art of War of Sunzi is taken out of the seven military books the Song set as the texts for examining military officers. The Six Secret Teachings is sixty chapters of questions and answers in which King Wen and King Wu ask Taigong Wang, running from the governing of a state to chariots, cavalry, battle in the open and the crossing of water; the Three Strategies is three short books said to have been given to Zhang Liang by Huang Shigong; the Wei Liaozi is twenty-four chapters setting down in detail the military orders and the squads of five and ten around the time of Qin; the Wuzi is six chapters of Wu Qi's answers to Marquis Wu of Wei; the Methods of the Sima is five chapters handing down the military rites of before the Spring and Autumn period; and Questions and Replies with Li Weigong is three books in which Taizong of Tang and Li Jing go back and forth over the unorthodox and the orthodox, the empty and the full, the frontier peoples and the Han, and attack and defense. "Arms are an instrument of ill omen," "bring the enemy to you and do not be brought to him," and "a thousand chapters and ten thousand phrases do not go beyond that one phrase" all come from here. The remaining six streams of the military school, read after the Art of War, are gathered in one place.
King Wu asked Taigong, "Troops are led deep into the land of the feudal lords, and the ruler and the general wish to join their forces, to work endless changes and to plan for gains beyond reckoning. The matters are many and troublesome, and tallies cannot make them clear. They are far apart from each other, and words do not reach. What should be done?" Taigong said, "When there are hidden matters and great plans, a letter should be used, and not a tally. The ruler sends a letter to the general, and the general asks the ruler by letter. Every letter is joined once and parted twice, and sent three times to be known at one stroke. Parted twice means that the letter is divided into three parts. Sent three times to be known at one stroke means that three men each carry one part, and they match them one against another but do not know the matter between them. This is called a secret letter (陰書). Though the enemy be sagely and wise, none can make it out." King Wu said, "Good."