To Overcome the Enemy, First Build Unity
To overcome the enemy, unity in one's camp is of primary importance. This is a proposition made in Basics of Military Strategies and Tactics written by Xu Dong in the Northern Song Dynasty. Unity means the support of the people. The ancient Chinese believed that "favorable weather conditions, geographic advantages, and the unity of the people" were the three factors determining victory and success, and that unity was the most important factor. Military conflict is a contest between two forces, particularly a contest of human strength, thus the importance of unity within the military ranks and the support of the whole population will make one strong and ensure victory. This is similar to the saying that "triumph comes when leaders and follows share the same goal." It also stresses the importance of a basic Chinese value, namely, putting the human factor first.
Favorable weather conditions, geographic advantages, and the unity of the people must all be in place. If not, even a victory will be a very costly one. (Sun Bin's Art of War)
Favorable weather conditions are not as valuable as favorable geographic conditions, and favorable geographic conditions are not as valuable as the unity of the people. (Mencius)
In conducting military operations, planning before battle is essential... To defeat the enemy, it is necessary to unite people around the same goal. (Xu Dong: Basics of Military Strategies and Tactics)