Sun-Tzu: The Art of War:
Planning The Attack
Master Sun said:
The art of warfare is this:
It is best to keep one's own state intact; to crush the enemy's state is only a second best. It is best to keep one's own army, battalion, company, or five-man squad intact; to crush the enemy's army, battalion, company, or five-man squad is only a second best. So to win a hundred victories in a hundred battles is not the highest excellence; the highest excellence is to subdue the enemy's army without fighting at all.
Therefore, the best military policy is to attack strategies; the next to attack alliances; the next to attack soldiers; and the worst to assault walled cities.
Resort to assaulting walled cities only when there is no other choice. To construct siege screens and armored personnel vehicles and to assemble all of the military equipment and weaponry necessary will take three months, and to amass earthen mounds against the walls will take another three months. And if your commander, unable to control his temper, sends your troops swarming at the walls, your casualties will be one in three and still you will not have taken the city. This is the kind of calamity that befalls you in laying siege.
Therefore, the expert in using the military subdues the enemy's forces without going to battle, takes the enemy's walled cities without launching an attack, and crushes the enemy's state without a protracted war. He must use the principel of keeping himself intact to compete in the world. Thus, his weapons will not be blunted and he can keep his edge intact. This then is the art of planning the attack.
Therefore the art of using troops is this:
When ten times the enemy strength, surround him; when five times, attack him; when double, engage him; when you and the enemy are equally matched, be able to divide him; when you are inferior in numbers, be able to take the defensive; and when you are no match for the enemy, be able to avoid him. Thus what serves as secure defense against a small army will only be captured by a large one.
The commander is the side-guard on the carriage of state. Where this guard is in place, the state will certainly be strong; where it is defective, the state will certainly be weak.
There are three ways in which the ruler can bring grief to his army:
To order an advance, not realizing the army is in no position to do so, or to order a retreat, not realizing the army is in no position to withdraw - this is called "hobbling the army."
To interfere in the administration of the army while being ignorant of its internal affairs will confuse officers and soldiers alike.
To interfere in military assignments while being ignorant of exigencies will lose him the confidence of his men.
Once his army has become confused and he has lost the confidence of his men, aggression from his neighboring rulers will be upon him. This is called sowing disorder in your own ranks and throwing away the victory.
Therefore ther are five factors in anticipating which side will win:
The side that knows when to fight and when not to will take the victory.
The side that understands how to deal with numerical superiority and inferiority in the deployment of troops will take the victory.
The side that has superiors and subordinates united in purpose will take the victory.
The side that fields a fully prepared army against one that is not will take the victory.
The side on which the commander is able and the ruler does not interfere will take the victory.
These five factors are the way (tao) of anticipating victory.
Thus it is said:
He who knows the enemy and himself
Will never in a hundred battles be at risk;
He who does not know the enemy but knows himself
Will sometimes win and sometimes lose;
He who knows neither the enemy nor himself
Will be at risk in every battle.