Military tactics are like unto water; for water in its natural course runs away from high places and hastens downwards... Water shapes its course according to the nature of the ground over which it flows; the soldier works out his victory in relation to the foe whom he is facing. Therefore, just as water retains no constant shape, so in warfare there are no constant conditions. He who can modify his tactics in relation to his opponent and thereby succeed in winning, may be called a heaven-born captain.
There are five dangerous faults which may affect a general: recklessness, which leads to destruction; cowardice, which leads to capture; a hasty temper, which can be provoked by insults; a delicacy of honour, which is sensitive to shame; over-solicitude for his men, which exposes him to worry and trouble.
Those who excel in war first cultivate their own humanity and and maintain their laws and institutions. By these means they make their governments invincible.
Thus it is that in war the victorious strategist only seeks battle after the victory has been won, whereas he who is destined to defeat first fights and afterwards looks for victory.
The military has no constant form, just as water has no constant shape - adapt as you face the enemy, without letting them know beforehand what you are going to do.
It is only the enlightened ruler and the wise general who will use the highest intelligence of the army for the purposes of spying, and thereby they achieve great results.
If, however, you are indulgent, but unable to make your authority felt; kind-hearted, but unable to enforce your commands; and incapable, moreover, of quelling disorder: then your soldiers must be likened to spoilt children; they are useless for any practical purpose.
Generally, management of many is the same as management of few. It is a matter of organization. And to control many is the same as to control few. This is a matter of formations and signals.
By altering his arrangements and changing his plans, the skillful general keeps the enemy without definite knowledge. By shifting his camp and taking circuitous routes, he prevents the enemy from anticipating his purpose. At the critical moment, the leader of an army acts like one who has climbed up a height and then kicks away the ladder behind him.
Whoever is first in the field and awaits the coming of the enemy, will be fresh for the fight; whoever is second in the field and has to hasten to battle will arrive exhausted.