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

When you surround an army, leave an outlet free. Do not press a desperate foe too hard.

In a position of this sort, even though the enemy should offer us an attractive bait, it will be advisable not to stir forth, but rather to retreat, thus enticing the enemy in his turn; then, when part of his army has come out, we may deliver our attack with advantage.

When envoys are sent with compliments in their mouths, it is a sign that the enemy wishes for a truce. If the enemy's troops march up angrily and remain facing ours for a long time without either joining battle or removing demands, the situation is one that requires great vigilance and circumspection. To begin by bluster, but afterward to take fright at the enemy's numbers, shows a supreme lack of intelligence.

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

Agitate him and ascertain the pattern of his movement.

Without local guides, your enemy employs the land as a weapon against you.