If you are strong, appear weak. But if you are weak, appear strong.

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

Let your plans be dark and impenetrable as night.

It is ten thousand times cheaper to pay the best spies lavishly than even a tiny army poorly.

And therefore those skilled in war bring the enemy to the field of battle and are not brought there by him.

The ultimate in disposing one's troops is to be without ascertainable shape. Then the most penetrating spies cannot pry in nor can the wise lay plans against you.

He who knows his enemy and himself well will not be defeated easily.