Of all those in the army close to the commander, none is more intimate than the secret agent.

The expert in battle seeks his victory from strategic advantage and does not demand it from his men.

He who knows things, and in fighting puts his knowledge into practice, will win his battles. He who knows them not, nor practices them, will surely be defeated.

He who wishes to fight must first count the cost

There are routes not to be followed, armies not to be attacked, citadels not to be besieged, territory not to be fought over.

So the principles of warfare are: Do not depend on the enemy not coming, but depend on our readiness against him. Do not depend on the enemy not attacking, but depend on our position that cannot be attacked.

The natural formation of the country is the soldier's best ally; but a power of estimating the adversary, of controlling the forces of victory, and of shrewdly calculating difficulties, dangers and distances, constitutes the test of a great general.