In warfare, there are no constant conditions. He who can modify his tactics in relation to his opponent will succeed and win.

If not in the interests of the state, do not act. If you cannot succeed, do not use troops. If you are not in danger, do not fight.

No ruler should put troops into the field merely to gratify his own spleen; no general should fight a battle simply out of pique. If it is to your advantage, make a forward move; if not, stay where you are. Anger may in time change to gladness; vexation may be succeeded by content. But a kingdom that has once been destroyed can never come again into being; nor can the dead ever be brought back to life.

When the general is weak and without authority; when his orders are not clear and distinct; when there are no fixed duties assigned to officers and men, and the ranks are formed in a slovenly haphazard manner, the result is utter disorganization.

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

A sovereign of high character and intelligence must be able to know the right man, should place the responsibility on him, and expect results.

Should the enemy strengthen his van, he will weaken his rear; should he strengthen his rear, he will weaken his van; should he strengthen his left, he will weaken his right; should he strengthen his right, he will weaken his left. If he sends reinforcements everywhere, he will everywhere be weak.