Success in warfare is gained by carefully accommodating ourselves to the enemy's purpose.

Rapidity is the essence of war: take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots.

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.

Energy may be likened to the bending of a crossbow; decision, to the releasing of a trigger.

What the ancients called a clever fighter is one who not only wins, but excels in winning with ease.

He who relies solely on warlike measures shall be exterminated; he who relies solely on peaceful measures shall perish.

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.