First learn to become invincible, then wait for your enemy's moment of vulnerability.

With regard to narrow passes, if you can occupy them first, let them be strongly garrisoned and await the advent of the enemy.

Be extremely subtle, even to the point of formlessness. Be extremely mysterious, even to the point of soundlessness. Thereby you can be the director of the opponent's fate.

One need not destroy one's enemy. One need only destroy his willingness to engage.

Do not press an enemy at bay.

Therefore, just as water retains no constant shape, so in warfare there are no constant conditions.

Great results, can be achieved with small forces.