Variation in Tactics

I In war the general takes his commands from the ruler, raises the army, and gathers the men. Then he reads the ground. On broken ground, do not camp. Where the roads cross, link up with your allies. On cut-off ground, do not linger. On hemmed-in ground, scheme your way out. On dead ground, fight. Sunzi said: In the use of troops, the general receives his commands from the ruler, joins the army, and assembles the host. On ground that is hard to cross, do not encamp. On ground where highways meet, join with your allies. On isolated ground, do not stay. On enclosed ground, make a plan. On ground of death, fight.

There are roads you do not take. There are armies you do not strike. There are towns you do not besiege. There is ground you do not fight for. There are orders from the ruler you do not obey. There are roads not to be travelled, armies not to be attacked, walled towns not to be besieged, ground not to be contested, and commands of the ruler not to be obeyed.

The general who can bend with these changes knows how to use troops. The one who cannot, though he has read the terrain, draws nothing from it. Drill an army by fixed rule, blind to variation, and even with the lay of the land in hand you will not get the use of your men. So the general who is versed in the advantages of the nine variations knows how to use troops. The general not versed in those advantages, though he knows the terrain, cannot gain the advantage of the ground. To command troops without knowing the art of the nine variations — though you know the ground's advantage, you cannot get the full use of your men.

“Do not count on the enemy not coming. Count on your own readiness to meet him.”

So the wise commander weighs gain and harm in the same thought. Reckon in the gain, and you can trust the plan to hold. Reckon in the harm, and you can clear the trouble before it lands. Therefore the considerations of the wise are sure to blend gain and harm. Blending in the gain, the task can be made dependable. Blending in the harm, the trouble can be resolved.

Bend a rival power by the harm you can do it. Keep it busy with tasks that wear it down. Set it running with the lure of advantage. And so you bend the other lords with harm, keep them toiling with affairs, and set them rushing with advantage.

So this is the rule of war. Do not count on the enemy not coming. Count on your own readiness to meet him. Do not count on his not attacking. Count on holding a position he cannot break. So the rule in using troops is this: do not rely on the enemy's not coming, but rely on your own readiness for him; do not rely on his not attacking, but rely on having a position that cannot be attacked.

Five faults can wreck a general. Set only on dying, and he can be killed. Set only on living, and he can be taken. Quick to anger, and he can be baited. Too jealous of his honor, and he can be shamed into a blunder. Too tender toward his people, and he can be worn down. So the general has five dangers. Bent on death, he can be killed. Bent on survival, he can be captured. Quick to anger, he can be provoked. Scrupulous about honor, he can be shamed. Loving the people, he can be harassed.

These five are flaws in the man and disaster in the field. When an army is broken and its general killed, the cause will lie among these five. They are not to be left unexamined. These five are faults in a general and calamities in the use of troops. When an army is overthrown and its general slain, it will surely be by these five dangers. They must be examined.

九變 The original Chinese · honored as an artifact

孫子曰：凡用兵之法，將受命於君，合軍聚眾；圮地無舍，衢地合交，絕地無留，圍地則謀，死地則戰。

Opening lines, classical Chinese · The Art of War 孫子兵法