Ancient Chinese military books. Xu Dong, a native of Wu County in the Northern Song Dynasty (now Wuxian County, Jiangsu Province), took four years to compile it in the first year of Jingde (1004). It has 20 volumes and 210 articles, discussing 210 issues. The main purpose of the "Tiger Signal Sutra" is to talk about people's plans at the top, geographical advantages in the middle, and weather and timing at the bottom. It also covers the wind and angles to predict weather conditions, people and horses to provide medical care, etc. Xu Dong believed that the relationship between heaven, earth, and humans should be "human first, earth second, and heaven next", and he valued the role of humans in war. Generals are required to "observe the enemy's movements" and use their troops flexibly, so as to "respond to the enemy with hypocrisy". Although the weather may be good or bad, the terrain may be dangerous, and the battle situation may be favorable, if you can see the bad in the good, the good in the bad, the easy in the easy, the easy in the dangerous, the bad in the good, and the good in the bad, you can use your troops to make the most of it. He also believed that to win, one must "take grain storage as the basis and strategy as a tool." Before fighting, you must "plan first": if you want to use troops, first plan to secure the people; if you want to attack the enemy, first plan to provide food; if you want to plan to spread out the enemy, first plan for geographical advantages; if you want to plan to defeat the enemy, first plan for peace; if you want to plan for defense, first plan for savings; if you want to plan for strong troops, first plan for rewards and punishments, etc. After the battle, first, we must be good at "seizing advantage", including seizing air, seizing passes, seizing courage, etc.; Second, we must be good at "attacking the weak," using feints to lure the enemy into attacking his weak point; third, we must "allow the situation", taking advantage of the opportunity to attack the enemy's slack, setting up an ambush to surprise the enemy, and taking advantage of victory to expand the results of the battle. The book also emphasizes "reverse application of ancient methods" and "advantage lies in flexibility." The book collects military-related knowledge on astronomy, calendar, timekeeping, and identification of directions, many of which were rarely found in military books in the past. In addition, the book also collects many formations and created formations such as Fei Ou and Chang Hong. In terms of style, the book is organized into categories and elaborated according to categories, which has been used as a reference for many military books of later generations.
