If the enemy strengthen his front, he must weaken his rear; if he strengthen his right, his left is weakened; and if he strengthen his left, his right is weakened.
Everywhere to make preparations, is to be everywhere weak. The enemy is weakened by his extended preparations, and we gain in strength.
Having decided on the place and day of attack, though the enemy be a hundred leagues away, we can defeat him.
If the ground and occasion be not known, the front cannot help the rear; the left cannot support the right, nor the right the left, nor the rear the front. For on occasion, the parts of the army are two score leagues apart, while a distance of four or five leagues is comparatively close.
The soldiers of Wu[10] are less than the soldiers of Yueh; but as superiority in numbers does not of necessity bring victory, I say, then, that we may obtain the victory.
If the enemy be many in number, prevent him from taking advantage of his superiority, and ascertain his plan of operations. Provoke the enemy and discover the state of his troops; feint and discover the strength of his position. Flap the wings, and unmask his sufficiency or insufficiency. By constant feints and excursions, we may produce on the enemy an impression of intangibility, which neither spies nor art can dispel.
The general makes his plans in accordance with the dispositions of the enemy, and puts his hosts in motion; but the multitude cannot appreciate the general’s intention; they see the signs of victory, but they cannot discover the means.
If a victory be gained by a certain stratagem, do not repeat it. Vary the stratagem according to circumstances.
An army may be likened to water.