兵之所加，如以□①投卵者，虚实是也。
That the impact of your army may be like a grindstone dashed against an egg--this is effected by the science of weak points and strong.

凡战者，以正合，以奇胜。
In all fighting, the direct method may be used for joining battle, but indirect methods will be needed in order to secure victory.

故善出奇者，无穷如天地，不竭如江海。终而复始，日月是也。死而更生，四时是也。
Indirect tactics, efficiently applied, are inexhaustible as Heaven and Earth, unending as the flow of rivers and streams; like the sun and moon, they end but to begin anew; like the four seasons, they pass away to return once more.

声不过五，五声之变，不可胜听也；
There are not more than five musical notes, yet the combinations of these five give rise to more melodies than can ever be heard.

色不过五，五色之变，不可胜观也；
There are not more than five primary colors (blue, yellow, red, white, and black), yet in combination they produce more hues than can ever been seen.

味不过五，五味之变，不可胜尝也；
There are not more than five cardinal tastes (sour, acrid, salt, sweet, bitter), yet combinations of them yield more flavors than can ever be tasted.

战势不过奇正，奇正之变，不可胜穷也。
In battle, there are not more than two methods of attack--the direct and the indirect; yet these two in combination give rise to an endless series of maneuvers.

奇正相生，如循环之无端，孰能穷之哉！
The direct and the indirect lead on to each other in turn. It is like moving in a circle--you never come to an end. Who can exhaust the possibilities of their combination?

激水之疾，至于漂石者，势也；
The onset of troops is like the rush of a torrent which will even roll stones along in its course.

鸷鸟之疾，至于毁折者，节也。
The quality of decision is like the well-timed swoop of a falcon which enables it to strike and destroy its victim.

故善战者，其势险，其节短。
Therefore the good fighter will be terrible in his onset, and prompt in his decision.

势如扩弩，节如发机。
Energy may be likened to the bending of a crossbow; decision, to the releasing of a trigger.

纷纷纭纭，斗乱而不可乱；浑浑沌沌，形圆而不可败。
Amid the turmoil and tumult of battle, there may be seeming disorder and yet no real disorder at all; amid confusion and chaos, your array may be without head or tail, yet it will be proof against defeat.

乱生于治，怯生于勇，弱生于强。
Simulated disorder postulates perfect discipline, simulated fear postulates courage; simulated weakness postulates strength.

治乱，数也；勇怯，势也；强弱，形也。
Hiding order beneath the cloak of disorder is simply a question of subdivision; concealing courage under a show of timidity presupposes a fund of latent energy; masking strength with weakness is to be effected by tactical dispositions.

故善动敌者，形之，敌必从之；予之，敌必取之。
Thus one who is skillful at keeping the enemy on the move maintains deceitful appearances, according to which the enemy will act. He sacrifices something, that the enemy may snatch at it.

以利动之，以卒待之。
By holding out baits, he keeps him on the march; then with a body of picked men he lies in wait for him.

故善战者，求之于势，不责于人故能择人而任势。
The clever combatant looks to the effect of combined energy, and does not require too much from individuals. Hence his ability to pick out the right men and utilize combined energy.

任势者，其战人也，如转木石。木石之性，安则静，危则动，方则止，圆则行。
When he utilizes combined energy, his fighting men become as it were like unto rolling logs or stones. For it is the nature of a log or stone to remain motionless on level ground, and to move when on a slope; if four-cornered, to come to a standstill, but if round-shaped, to go rolling down.

故善战人之势，如转圆石于千仞之山者，势也。
Thus the energy developed by good fighting men is as the momentum of a round stone rolled down a mountain thousands of feet in height. So much on the subject of energy.

【注：】①：“瑕”的“王”旁换“石”旁。

虚实第六
VI. Weak Points and Strong

孙子曰：凡先处战地而待敌者佚，后处战地而趋战者劳。
Sun Tzu said: 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.

故善战者，致人而不致于人。
Therefore the clever combatant imposes his will on the enemy, but does not allow the enemy's will to be imposed on him.

能使敌人自至者，利之也；能使敌人不得至者，害之也。
By holding out advantages to him, he can cause the enemy to approach of his own accord; or, by inflicting damage, he can make it impossible for the enemy to draw near.

故敌佚能劳之，饱能饥之，安能动之。
If the enemy is taking his ease, he can harass him; if well supplied with food, he can starve him out; if quietly encamped, he can force him to move.

出其所必趋，趋其所不意。
Appear at points which the enemy must hasten to defend; march swiftly to places where you are not expected.

行千里而不劳者，行于无人之地也；
An army may march great distances without distress, if it marches through country where the enemy is not.

攻而必取者，攻其所不守也。守而必固者，守其所必攻也。
You can be sure of succeeding in your attacks if you only attack places which are undefended. You can ensure the safety of your defense if you only hold positions that cannot be attacked.

故善攻者，敌不知其所守；善守者，敌不知其所攻。
Hence that general is skillful in attack whose opponent does not know what to defend; and he is skillful in defense whose opponent does not know what to attack.

微乎微乎，至于无形；神乎神乎，至于无声，故能为敌之司命。
O divine art of subtlety and secrecy! Through you we learn to be invisible, through you inaudible; and hence we can hold the enemy's fate in our hands.

进而不可御者，冲其虚也；退而不可追者，速而不可及也。
You may advance and be absolutely irresistible, if you make for the enemy's weak points; you may retire and be safe from pursuit if your movements are more rapid than those of the enemy.