The peak efficiency of knowledge and strategy is to make conflict unnecessary.

Thus it is that in war the victorious strategist only seeks battle after the victory has been won, whereas he who is destined to defeat first fights and afterwards looks for victory.

The sovereign must have full knowledge of the activities of the five sorts of agents. This knowledge must come from the double agents, and therefore it is mandatory that they be treated with the utmost liberality.

The proximity of an army causes prices to go up; and high prices cause people's substance to be drained away. When their substance is drained away, they will be afflicted by heavy exactions. With this loss of substance and exhaustion of strength, the homes of the people will be stripped bare, and their incomes dissipated.

All warfare is based on deception. If your enemy is superior, evade him. If angry, irritate him. If equally matched, fight and if not: split and re-evaluate.

Quickness is the essence of the war.

Hostile armies may face each other for years, striving for the victory which is decided in a single day. This being so, to remain in ignorance of the enemy's condition simply because one grudges the outlay of a hundred ounces of silver in honors and emoluments, is the height of inhumanity.