When you are ignorant of the enemy but know yourself, your chances of winning or losing are equal.

It is a doctrine of war not to assume the enemy will not come, but rather to rely on one's readiness to meet him; not to presume that he will not attack, but rather to make one's self invincible.

The art of war teaches us to rely not on the likelihood of the enemy's not coming, but on our own readiness to receive him; not on the chance of his not attacking, but rather on the fact that we have made our position unassailable.

Attack where he is unprepared; sally forth when he does not expect you.

All warfare is based on deception. Hence, when able to attack, we must seem unable; when using our forces, we must seem inactive; when we are near, we must make the enemy believe we are far away; when far away, we must make him believe we are near.

Those skilled in attack move as from above the nine-fold heavens. Thus they are capable both of protecting themselves and of gaining complete victory.

Hold out baits to entice the enemy. Feign disorder, and crush him.