Xushi — the empty and the full虛實篇

力有餘也。

There is strength to spare.

先處形勝之地以待敵者，則有備豫，士馬閑逸。

Take the ground that lies better first and wait for the enemy, and your preparation is made beforehand, so that men and horses are at leisure and at ease.

杜佑同賈林《註》。

Du You's (杜佑) note is the same as Jia Lin's (賈林).

王晳同曹操《註》。

Wang Xi's (王晳) note is the same as Cao Cao's (曹操).

形勢之地，我先據之，以待敵人之來，則士馬閑逸，而力有餘。

When I take ground that lies well first and wait for the enemy to come, men and horses are at leisure and at ease, and there is strength to spare.

力不足也。《太一遁甲》云︰「彼來攻我，則我爲主，彼爲客，主易客難也。」是以《太一遁甲》言其定計之義，故知勞佚事不同，先後勢異。

Because their strength falls short. The *Taiyi Dunjia* (太一遁甲) says, "When they come and strike me, I am the host and they are the guest; the host has it easy and the guest has it hard." It is in this that the *Taiyi Dunjia* speaks of the meaning of settling a plan, and from it one can know that toil and ease are not the same business, and that coming first and coming after differ in their momentum.

後周遣將，帥突厥之衆逼齊，齊將段韶禦之。時大雪之後，周人以步卒爲前鋒，從西而下，去城二里。諸將欲逆擊之，韶曰︰「步人氣力勢自有限，今積雪旣厚，逆戰非便，不如陳以待之；彼勞我佚，破之必矣。」旣而交戰，大破之，前鋒盡殪，自餘遁矣。

The Later Zhou (後周) sent a general to lead the host of the Tujue (突厥) and press Qi (齊), and Duan Shao (段韶), a general of Qi, blocked him. It was after a great snow, and the men of Zhou put their foot soldiers in the van and came down from the west until they were two li from the city. The generals wished to go out and meet them, but Duan Shao said, "The spirit and strength of men on foot have a limit of their own by the nature of things. The snow is piled thick already, and going out to meet them is not convenient. Better to draw up our lines and wait for them. They toil and we are at ease, so breaking them is certain." Soon they closed and broke them utterly: the van was killed to the last man and the rest fled away.

敵處便利，我則不往，引兵別據，示不敵其軍；敵謂我無謀，必來攻襲。如此，則反令敵倦，而我不勞。

If the enemy takes the easeful ground, I do not go to him but draw my troops off and take ground apart, showing that I cannot stand against his host. The enemy takes me for a man without a plan and is sure to come and strike and fall upon me. Do this, and it is the enemy who is worn out instead, while I do not toil.

若敵已處便勢之地，己方赴利，士馬勞倦，則不利矣。

If the enemy has already taken the ground that lies easeful, and only then do I run after the advantage, men and horses are worn out and there is no gain in it.

先至待敵則力完，後至趨戰則力屈。

Arrive first and wait for the enemy, and your strength is whole; arrive after and hurry into the fight, and your strength is broken.

戰國秦師伐韓，圍閼與，趙遣將趙奢救之。軍士許歷曰︰「秦人不意趙師至此，其來氣盛。將軍必厚集其陳以待之，不然必敗。」又曰︰「先據北山者勝，後至者敗。」趙奢卽發萬人趨之。秦兵後至，爭山，不得上。趙奢縱兵擊之，大破秦軍，遂解閼與之圍。後漢初，諸將征隗囂，爲囂所敗。光武令悉軍栒邑。未及至，隗囂乘勝使其將王元、行巡將二萬餘人下隴，因分遣巡取栒邑。漢將馮異卽馳馬欲先據之。諸將皆曰︰「虜兵盛而新乘勝，不可與爭，宜止軍便地，徐思方略。」異曰︰「虜兵方盛臨境，狃忲小利，遂欲深入；若得栒邑，三輔動搖，是吾憂也。夫攻者不足，守者有餘，今先據城，以佚待勞，非所以爭鋒也。」遂潛往，閉城，偃旗鼓。行巡不知，馳赴之。異乘其不意，卒擊鼓建旗而出，巡軍驚亂奔走，追而大破之。東魏將齊神武伐西魏，軍過蒲津，涉洛，至許原。西魏將周文帝軍至沙苑。齊神武聞周文至，引軍來會。詰朝，候騎告齊神武軍且至，周文步將李弼曰︰「彼衆我寡，不可平地置陳；此東十里有渭曲，可先據以待之。」遂軍至渭曲，背水東西爲陳。合戰，大破之。

In the age of the Warring States the troops of Qin (秦) struck Han (韓) and ringed Yanyu (閼與) about, and Zhao (趙) sent its general Zhao She (趙奢) to the rescue. The soldier Xu Li (許歷) said, "The men of Qin never reckoned that Zhao's troops would come this far, so the force of their coming is full. The general must gather his lines thick and wait; if he does not, he is sure to be beaten." He said also, "Whoever takes the North Hill (北山) first wins, and whoever comes to it after is beaten." Zhao She at once sent ten thousand men to run for it. The Qin troops came after and fought for the hill but could not climb it. Zhao She loosed his troops and struck, broke the Qin army utterly, and so raised the siege of Yanyu. Early in the Later Han (後漢) several generals struck Wei Ao (隗囂) and were beaten by him, and Guangwu (光武) had all the troops placed at Xunyi (栒邑). Before they arrived, Wei Ao rode the force of his victory and had his generals Wang Yuan (王元) and Xing Xun (行巡) lead more than twenty thousand men down to Long (隴), and then sent Xing Xun off to take Xunyi. The Han general Feng Yi (馮異) at once rode to take it first. The generals all said, "The barbarian troops are full and ride a fresh victory; we cannot contend with them. We should halt the army on easy ground and think out a plan at leisure." Feng Yi said, "The barbarian troops are at their fullest and have come close upon the border; they are used to small gains and mean at last to come in deep. If they get Xunyi, the Three Capital Districts (三輔) are shaken, and that is my care. In general the striker falls short and the holder has to spare; now I take the city first so as to wait upon their toil with my ease, and it is not a race for a day." So he went secretly, shut the gates of the city and hid his flags and drums. Xing Xun knew nothing of it and rode up. Feng Yi took him at unawares, suddenly beat his drums, raised his flags and went out; Xing Xun's troops were startled and fled in confusion, and he gave chase and broke them utterly. When Qi Shenwu (齊神武), general of the Eastern Wei (東魏), struck the Western Wei (西魏), his troops passed Pujin (蒲津), crossed the Luo (洛水) and came to Xuyuan (許原). Zhou Wendi (周文帝), general of the Western Wei, had his troops come as far as Shayuan (沙苑). Qi Shenwu heard that Zhou Wendi had come and led his troops out to meet him. Early in the morning the scouting horsemen reported that Qi Shenwu's troops were about to arrive, and Li Bi (李弼), Zhou Wendi's general of foot, said, "They are many and we are few, and we cannot draw up our lines on level ground. Ten li east of here is Weiqu (渭曲), and it is worth taking first and waiting there." So the troops came to Weiqu, put the water at their backs and drew up their lines east and west. They closed and broke them utterly.

便利之地，彼已據之，我方趨彼以戰，則士馬勞倦，而力不足。或謂所戰之地，我宜先到，立陳以待彼，則己佚矣。彼先結陳，我後至，則我勞矣。若宋人已成列，楚師未旣濟之類。

When the ground that is easeful and advantageous has already been taken by them, and only then do I run to fight them, men and horses are worn out and strength falls short. Some say instead: on the ground of battle I ought to arrive first, set up my lines and wait for them, and then I am at ease; if they knit their lines first and I come after, then I toil. It is like the men of Song (宋) having formed their ranks already while the troops of Chu (楚) had not all crossed over.

故能致人之勞，不致人之佚也。

And so he can make others toil and does not let others be at ease.

致令敵來就我，我當蓄力待之，不就敵人，恐我勞也。後漢張步將費邑分遣其弟敢守巨里。耿弇進兵，先脅巨里，使多伐樹木，揚言以填坑壍。數日，有降者言︰邑聞弇欲攻巨里，謀來救之。弇乃嚴令軍中趨修攻具，宣勒諸部，後三日當悉力攻巨里城。陰緩生口，令得亡歸。歸者以弇期告邑。至日，果自將精兵三萬餘人來救之。弇喜謂諸將曰︰「吾修攻具者，欲誘致邑耳；今來，適其所求也。」卽分三千人守巨里，自引精兵上岡阪，乘高大破之，遂臨陳斬費邑。

It is to make the enemy come and draw near me, while I pile up strength and wait and do not draw near him, because I fear that I shall toil. In the time of the Later Han, Fei Yi (費邑), a general of Zhang Bu (張步), sent his younger brother Gan (敢) off to hold Juli (巨里). Geng Yan (耿弇) brought his troops out, pressed Juli first, and had a great deal of timber cut, giving it out loudly that he would fill the pits and trenches with it. A few days later a man who came over said that Fei Yi, hearing that Geng Yan meant to strike Juli, had laid a plan to come to its rescue. Geng Yan then gave strict order through the camp to make the engines of attack ready in haste, and let it be known among all the units that in three days he would strike the walls of Juli with all his strength. He quietly let his watch on a captive slacken so that the man ran back, and the man who went back told Fei Yi the day Geng Yan had named. When the day came, Fei Yi did indeed lead more than thirty thousand picked men to the rescue. Geng Yan was glad and said to his generals, "My making the engines ready was to lure Fei Yi into coming. Now that he has come, it is just what I wished." He then told off three thousand men to hold Juli, led his picked troops up the hill himself, and from the high ground broke them utterly, and in the end cut Fei Yi down before his own lines.

言兩軍相遠，彊弱俱敵，彼可使歷險而來，我不可歷險而往；必能引致敵人，己不往從也。

It means that when the two armies are far apart and strong and weak are evenly matched, I can make them come across the broken ground but must not go across it myself. I must be able to draw the enemy in, and not go and follow after him.

能令敵來，則敵勞；我不往就，則我佚。

If I can make the enemy come, the enemy toils; if I do not go and draw near him, I am at ease.

致人者，以佚乘其勞；致於人者，以勞乘其佚。

The side that makes another come rides his toil with its own ease; the side that is drawn in by another rides his ease with its own toil.

令敵自來。

He makes the enemy come of himself.

致敵來戰，則彼勢常虛；不往赴戰，則我勢常實。此乃虛實彼我之術也。耿弇先逼巨里以誘致費邑，近之。

Make the enemy come and fight, and their momentum is always empty; do not go forward into the fight, and my momentum is always full. This is just the way of handling the empty and the full (虛實) on their side and mine. Geng Yan's pressing Juli first so as to lure Fei Yi into coming comes near to this.

誘之以利也。

This means luring them with the prospect of gain.

以利誘之，敵則自遠而至也。趙將李牧誘匈奴，則其義也。

Lure them with gain and the enemy comes of himself from far off. Li Mu (李牧), the general of Zhao, luring the Xiongnu (匈奴) is just this meaning.

李牧大縱畜牧，人衆滿野，匈奴小入，佯北不勝，以數千人委之。單于大喜，率衆來入，牧大破之，殺匈奴十萬騎。單于奔走，歲餘不敢犯邊也。

Li Mu let the herding of beasts go out widely, so that men filled the fields. When the Xiongnu came in a little way, he feigned a defeat as though he could not win, and left several thousand men behind. The Chanyu (單于) was greatly pleased and led his host in, and Li Mu broke them utterly and killed a hundred thousand Xiongnu horsemen. The Chanyu fled, and for more than a year he did not dare come over the border.

何能自來？示之以利。

How does one make them come of themselves? By showing them gain.

以利誘之而來，我佚敵勞。

Lure them with gain so that they come, and I am at ease while the enemy toils.

所以能致敵之來者，誘之以利耳。李牧佯北以致匈奴，楊素毁車以誘突厥是也。

The reason one can make the enemy come is nothing but that one lures him with gain. Li Mu feigning defeat to make the Xiongnu come, and Yang Su (楊素) breaking up his wagons to lure the Tujue, are this.

出其所必趨，攻其所必救。

Advance where the enemy must rush, and strike where the enemy must come to the rescue.

害其所急，彼必釋我而自固也。魏人宼趙邯鄲，乞師於齊。齊將田忌欲救趙，孫臏曰︰「夫解紛者不控捲，救鬬者不搏撠；批亢擣虛，形格勢禁，則自解爾。今二國相持，輕銳竭於外，疲老殆於內，我襲其虛，彼必解圍而奔命，所謂一舉存趙而弊魏也。」後魏果釋趙而奔大梁，遭齊人於馬陵，魏師敗績。

Harm what they are pressed for and they are sure to let go of me and look to making themselves firm. The men of Wei (魏) struck Handan (邯鄲) of Zhao, and Zhao begged troops of Qi. When Tian Ji (田忌), the general of Qi, meant to go to Zhao's rescue, Sun Bin (孫臏) said, "He who unties a tangle does not pull at it with his fist, and he who parts a fight does not trade blows. Draw back from where they are firm and strike where they are empty, so that their shape is blocked and their momentum caught, and it comes undone of itself. Now the two states stand against each other: their light and nimble troops are spent abroad and the worn and the old are in peril at home. If we fall upon their empty place, they are sure to raise the siege and run to save their lives. This is what is called saving Zhao and wearing Wei down at one stroke." Afterwards Wei did indeed let Zhao go and ran for Daliang (大梁), but met the men of Qi at Maling (馬陵), and the troops of Wei were beaten.

曹公攻河北，師次頓丘，黑山賊于毒等攻武陽。曹公乃引兵西入山，攻毒本屯。毒聞之，棄武陽還。曹公要擊於內，大破之也。

When Lord Cao (曹公) struck Hebei (河北), his troops were halted at Dunqiu (頓丘), and Yu Du (于毒) and the rest, bandits of Heishan (黑山), struck Wuyang (武陽). Lord Cao then led his troops west into the hills and struck Yu Du's own camp. Yu Du heard of it, abandoned Wuyang and came back; and Lord Cao met him from within and broke him utterly.

子胥疲楚師，孫臏走魏將之類也。

It is like Zixu (子胥) wearing down the troops of Chu, or Sun Bin putting the general of Wei to flight.

致其所必走，攻其所必救，能守其險害之要路，敵不得自至。故王子曰︰「一猫當穴，萬鼠不敢出；一虎當溪，萬鹿不敢過。」言守之上也。

Draw him to the place he must flee to and strike the place he must rescue; and if you can hold the vital roads that are broken and harmful, the enemy cannot come of himself. So the Prince (王子) said, "Let one cat block the hole and ten thousand rats dare not come out; let one tiger block the stream and ten thousand deer dare not pass." He was speaking of the first thing in holding ground.

敵不得來，當制之以害。

If you would keep the enemy from coming, you should press him down with harm.

以害形之，敵患之而不至。

Make a shape out of harm, and the enemy worries over it and does not come.

所以能令敵人必不得至者，害其所顧愛耳。孫臏直走大梁，而解邯鄲之圍是也。

The reason one can keep the enemy from coming is nothing but that one harms what they look to and hold dear. Sun Bin running straight for Daliang and so raising the siege of Handan is this.

以事煩之。

Stir up affairs to burden them.

攻其不意，使敵疲於奔命。

Strike where they do not look for it, so that the enemy is worn out with running to save his life.

高熲言平陳之策於隋祖曰︰「江北地寒，田收差晚。江南土熱，水田早熟。量彼收穫之際，微徵士馬，聲言掩襲，彼必屯兵禦守，足得廢其農時。彼旣聚兵，我便解甲。」於是，陳人始病。

Gao Jiong (高熲) laid before Gaozu (高祖) of Sui (隋) his plan for settling Chen (陳): "North of the river the ground is cold and the field harvest is late; south of the river the soil is warm and the paddy ripens early. Reckon the season when they gather in, call up a few troops and horses and give it out loudly that we will fall on them and strike; they are sure to gather troops to block and hold, and we can readily make them give up their farming season. When they gather troops, we at once take off our armor." With this the men of Chen began to sicken.

撓之，使不得休息。

Stir them up so that they get no rest.

巧致之也。

It is drawing them in by craft.

春秋時，吳王闔閭問於伍員曰︰「伐楚何如？」對曰︰「楚執政衆，莫適任患，若爲三師以肄焉︰一師至，彼必皆出；彼出則歸，彼歸則出，彼必道弊。亟肄以疲之，多方以誤之；旣罷而後，以三軍繼之，必大克之。」闔閭從之，楚於是乎始病。吳遂入郢。

In the age of the Spring and Autumn, King Helü (闔閭) of Wu (吳) asked Wu Yuan (伍員), "How would it be to strike Chu?" He answered, "In Chu there are many who hold the government, and not one of them takes its cares properly upon himself. Make three armies to harass them in turn, and when one army comes up they are sure to come out in full. When they come out we go back, and when they go back we go out, and they are sure to be worn down upon the road. Harass them often so that they are worn out, and lead them into error along many ways; and when they are worn out already, follow after them with the three armies, and a great victory is certain." Helü followed his word, and Chu then began to sicken, and Wu entered Ying (郢) in the end.

爲多方以誤之之術，使其不得休息。或曰︰彼若先處戰地以待我，則是彼佚也，我不可趨而與之戰。我旣不往，彼必自來，卽是變佚爲勞也。

He uses the way of leading them into error along many ways, so that they get no rest. Some say instead: if they have taken the ground of battle first and wait for me, then they are at ease, and I must not run and fight them. If I do not go, they are sure to come of themselves, and this is just turning ease into toil.

絶糧道以饑之。

Cut the grain road to starve them.

焚其積聚，芟其禾苗，絶其糧道。

Burn what they have stored up, cut the standing grain, and cut the road of their food.

我爲主，敵爲客，則可以絶糧道而饑之。如我爲客，敵爲主，則如之何？答曰︰饑敵之術，非止絶糧道，但能饑之則是。隋高熲平陳之策曰︰「江南土薄，舍多茅竹，有畜積，皆非地窖。密遣人因風縱火，待敵修立，更復燒之，不出數年，自可財力俱盡。」遂行其策，由是陳人益困。三國時，諸葛誕、文欽據壽春。及招吳請援，司馬景王討之，謂諸將曰︰「彼當突圍，決一朝之命；或謂大軍不能久，省食減口，冀有他變。料賊之情，不出此二者。當多方以亂之。」因命合圍，遣羸疾寄穀淮北廩，軍士豆人三升。誕、欽聞之，果喜。景王愈羸形以示之。誕等益寬，恣食。俄而城中糧盡，攻而拔之。隋末，宇文化及率兵攻李密於黎陽，密知化及糧少，因僞和之，以弊其衆。化及大喜，恣其兵食，冀密饋之。其後食盡，其將王智略、張童仁等率所部兵歸於密，前後相繼，化及以此遂敗。

If I am the host and the enemy the guest, I can cut the road of his food and starve him. And if I am the guest and the enemy the host, what then? I answer: the way of starving the enemy does not stop at cutting the road of his food; if only you can make him starve, that is it. Gao Jiong of Sui said, in his plan for settling Chen, "South of the river the soil is thin, and the houses have much thatch and bamboo, and what is stored up is none of it in earth-pits. Send men secretly to set fires with the wind, and wait till the enemy builds again and burn it once more; and in not many years his goods and his strength will come to nothing of themselves." The plan was carried out in the end, and by it the men of Chen were the more distressed. In the age of the Three Kingdoms, Zhuge Dan (諸葛誕) and Wen Qin (文欽) held Shouchun (壽春) and called upon Wu to come to their rescue. Sima Jingwang (司馬景王) struck them, and said to his generals, "They ought to break the ring and stake all upon a single morning. Or some may say that a great army cannot hold out long, and so cut down their eating and spare their mouths, hoping for some other turn. Reckon up the enemy's mind and it does not go beyond these two, and so we should throw them into disorder along many ways." He therefore ordered the ring closed, sent the lean and the sick to leave their grain in the storehouses north of the Huai (淮), and gave the soldiers three sheng of beans a man. Zhuge Dan and Wen Qin heard of it and were indeed pleased. Jingwang showed himself leaner still, and Zhuge Dan and the rest grew slacker and ate as they pleased. Soon the food within the walls was spent, and he struck and took the place. At the end of Sui, Yuwen Huaji (宇文化及) led troops and struck Li Mi (李密) at Liyang (黎陽). Li Mi knew that Yuwen Huaji's food was short and feigned a peace with him, so wearing his host down. Yuwen Huaji was greatly pleased, let his army eat as it pleased, and looked for Li Mi to send him grain. Afterwards his food ran out, and his generals Wang Zhilüe (王智略) and Zhang Tongren (張童仁) and the rest brought over the troops they led and went back to Li Mi, one after another; and by this Yuwen Huaji was beaten in the end.

饑敵之術，在臨事應機。

The way of starving the enemy lies in coming to the business and answering the signs of it.

要其糧，使不得饋。

Block his food so that it cannot be sent through.

謂敵人足食，我能使之饑乏耳。曹公曰︰「絶其糧道。」晳謂︰火積亦是也。

It means that though the enemy have food enough, I can make him starve and fall short. Lord Cao said, "Cut the road of his food." Wang Xi says that burning up what he has stored is this too.

如吳楚反，周亞夫曰︰「楚丘剽輕，難與爭鋒，願以梁委之，絶其食道，乃可制也。」亞夫會兵滎陽，吳攻梁，梁急，請救。亞夫引兵東北，走昌邑，深壁而守，使輕騎弓高侯等絶吳、楚兵後食道。兵乏糧，饑，欲退，數挑戰，終不出，乃引兵去。精兵追擊，大破之。王莽末，天下亂，光武兄伯升起兵討莽，爲莽將甄阜、梁丘賜所敗，復收會兵衆，還保於棘陽。阜、賜乘勝留輜重於藍鄉，引精兵十餘萬人南渡，橫臨沘水。阻兩山間爲營，絶後橋，示無還心。伯升於是大饗軍士，設盟約，休卒三日，爲六部，潛師夜起，襲取藍鄉，盡獲其輜重。明晨，自南攻甄阜，下江兵自東南攻梁丘賜。乏食陳潰，遂斬阜、賜。唐輔公祏遣其僞將馮惠亮、陳當世領水軍屯於博望山。陳正通、徐紹宗率步騎軍於青州山。河間王孝恭至，堅壁不與鬬，使奇兵斷其糧道。賊漸餒，夜薄我營，孝恭安卧不動。明日，縱羸兵以攻賊壘，使盧祖尚率精騎列陳以待之。俄而攻壘者敗走，出追，奔數里，遇祖尚軍，與戰，大敗之，正通棄營而走。

When Wu and Chu rose in revolt, Zhou Yafu (周亞夫) said, "The troops of Chu are nimble and light, and it is hard to match them for a day. Leave Liang (梁) to them and cut the road of their eating, and then they can be held down." Zhou Yafu gathered his troops at Xingyang (滎陽); and when Wu struck Liang, Liang was hard pressed and begged rescue. Zhou Yafu led his troops northeast to Changyi (昌邑), made his ramparts deep and held them, and sent the light horsemen under the Marquis of Gonggao (弓高侯) and the rest to cut the road of eating behind the troops of Wu and Chu. The enemy's troops fell short of grain and starved and meant to draw off; several times they offered battle, but he would never come out, and in the end they led their troops away. He gave chase with light troops and struck them and broke them utterly. At the end of Wang Mang's (王莽) time the realm was in disorder, and Bosheng (伯升), the elder brother of Guangwu, raised troops and struck Wang Mang, but was beaten by Wang Mang's generals Zhen Fu (甄阜) and Liangqiu Ci (梁丘賜); he gathered his troops again and went back to hold Jiyang (棘陽). Zhen Fu and Liangqiu Ci rode the force of their victory, left their baggage at Lanxiang (藍鄉), and led more than a hundred thousand picked men south across the country until they came up against the Bi (沘水). They barred the space between two hills and drew up their lines, and cut the bridge behind them to show that they had no mind to go back. Bosheng then fed his troops well, took an oath with them and let them rest three days; then he split them into six bodies, raised them secretly by night, fell upon Lanxiang and took it, and got all their baggage. At dawn the next day he struck Zhen Fu himself from the south, while the troops of Xiajiang (下江) struck Liangqiu Ci from the southeast. Their food was short and their lines broke, and so he cut down Zhen Fu and Liangqiu Ci. Fu Gongshi (輔公祏) of Tang (唐) sent his pretended generals Feng Huiliang (馮惠亮) and Chen Dangshi (陳當世) to lead the water forces and halt at Mount Bowang (博望山), and set Chen Zhengtong (陳正通) and Xu Shaozong (徐紹宗) with the foot and the horse at Mount Qingzhou (青州山). Xiaogong (孝恭), Prince of Hejian (河間王), came up, made his ramparts firm and would not contend, and had a surprise force (奇兵, troops brought out where they are not looked for) cut the road of their food. The enemy grew hungry little by little and came up to our lines at night, but Xiaogong lay at ease and did not stir. The next day he loosed his lean troops to strike the enemy's ramparts, and had Lu Zushang (盧祖尚) lead the light horse, draw up his lines and wait. Soon those who struck the ramparts were beaten and fled, and the enemy came out and gave chase for some li, but met Lu Zushang's troops and fought and were utterly beaten, and Chen Zhengtong abandoned his lines and fled.

我先舉兵，則我爲客，彼爲主。爲客，則食不足；爲主，則飽有餘。若奪其畜積，掠其田野，因糧於彼，館穀於敵，則我反飽，彼反饑矣，則是變客爲主也。不必焚其積聚，廢其農時，然後能饑敵矣。或彼爲客，則絶其糧道，廣武君欲請奇兵以遮絶韓信軍後是也。

If I raise troops first, I am the guest and they are the host. Be the guest and food falls short; be the host and you are full and have to spare. If I take what they have stored and plunder their fields and wilds, getting my grain from them and eating the enemy's crop, then I am full instead and they starve instead, and this is turning the guest into the host. It is not that one must burn what they have stored and make them give up the farming season before the enemy can be starved. Or if they are the guest, cut the road of their food: the Lord of Guangwu (廣武君) asking for a surprise force to bar and cut the road behind Han Xin's (韓信) troops is this.

攻其所必愛，出其所必趨，則使敵不得不相救也。

Strike what the enemy must hold dear and advance where the enemy must rush, and you leave them no choice but to go to one another's rescue.

出其所必趨，擊其所不意，攻其所必愛，使不得不救也。

Come out where he must run, strike where he does not look for it, and strike what he must hold dear, so that he cannot help coming to the rescue.

司馬宣王攻公孫文懿於遼東，阻遼水以拒魏軍。宣王曰︰「賊堅營高壘以老我師，攻之正入其計。古人云︰敵雖高壘，不得不與我戰者，攻其所必救。我今直指襄平，則人懷內懼，懼而求戰，破之必矣。」遂整陳而過。賊見兵出其後，果來邀之，乃縱擊，大破之，竟平遼東。

When Sima Xuanwang (司馬宣王) struck Gongsun Wenyi (公孫文懿) in Liaodong (遼東), the enemy barred the Liao (遼水) and stood against the troops of Wei. Xuanwang said, "The enemy makes his lines firm and his ramparts high, meaning to wear our troops out; to strike them is to walk straight into his plan. The men of old said that what makes an enemy unable to help fighting you, though he raise his ramparts high, is striking the place he must rescue. If I now point straight at Xiangping (襄平), men will bear fear in their hearts; and when they fear, they will seek battle, and breaking them is certain." So he put his lines in order and marched past. The enemy, seeing troops come out behind him, did indeed come to block him, and he then loosed his men and struck and broke them utterly, and so settled Liaodong.

《左傳》楚伐宋，宋告急於晉。晉先軫曰︰「我執曹君，而分曹、衞之田以賜宋人，楚愛曹、衞，必不許也。喜賂怒頑，能無戰乎？」遂破楚師。

In the *Zuo Commentary* (左傳), when Chu struck Song, Song told Jin (晉) of its straits. Xian Zhen (先軫) of Jin said, "If we take the ruler of Cao (曹) and divide the fields of Cao and Wei (衞) and give them to the men of Song, Chu holds Cao and Wei dear and is sure not to allow it. One side is glad at what it has got and the other angry at being withstood; could they then not fight?" And so they broke the troops of Chu.

孟氏《註》同曹操。

Meng's (孟氏) note is the same as Cao Cao's.

趨其所顧，使不得止。

Run to the place they look to, so that they cannot stay still.

王晳同李筌《註》。

Wang Xi's note is the same as Li Quan's (李筌).

攻其所愛，豈能安視而不動哉？

Strike what he holds dear, and how should he look on at ease and not stir?

彼方安守，以爲自固之術，不欲速戰，則當攻其所必救，使不得已而須出。臾駢堅壁，秦伯挑其裨將，遂皆出戰是也。

When they are keeping quiet and making that their way of holding themselves firm, and will not fight soon, you should strike the place they must rescue, so that they have no choice but to come out. Yu Pian (臾駢) making his ramparts firm, and the Earl of Qin (秦伯) challenging his second general so that they all came out and fought in the end, is this.

使敵不得相往而救之也。

This is to keep the enemy from going back and forth to rescue one another.

令敵人須應我。

He makes the enemy answer him of necessity.

出空擊虛，避其所守，擊其不意。

Go out into the empty ground and strike where they are empty; avoid what they guard and strike where they do not expect it.

出敵無備，從孤擊虛，何人之有？

Come out where the enemy is not prepared, follow the out-of-the-way places and strike where he is empty: what men would there be?

梁元帝時，西蜀稱帝，率兵東下，將攻元帝。西魏大將周文帝曰︰「平蜀制梁，在茲一舉。」諸將多有異同。文帝謂將軍尉遲迥曰︰「伐蜀之事，一以委公。然計將安出？」迥曰︰「蜀與中國隔絶百餘年矣，恃其山川險阻，不虞我師之至，宜以精甲銳騎星夜奔襲之。平路則倍道兼行，險途則緩兵漸進。出其不意，衝其腹心，必向風不守。」竟以平蜀。言不勞者，空虛之地，無敵人之虞，行止在我，故不勞也。

In the time of Emperor Yuan (元帝) of Liang, Western Shu (西蜀) took the title of sovereign and meant to lead troops down east and strike Emperor Yuan. Zhou Wendi, the great general of the Western Wei, said, "Settling Shu (蜀) and holding Liang down lies in this one stroke." The generals were of different minds. Wendi said to the general Yuchi Jiong (尉遲迥), "The striking of Shu I leave wholly to you. But how will you lay the plan?" Yuchi Jiong said, "Shu has been cut off from the Middle Kingdom a hundred years and more; it trusts only in the broken ground of its hills and streams and does not trouble that our troops might come. We should go with stout armor and light horse, riding through the night to fall upon them. On level roads we make two days' march in one; on broken roads we slow the troops and go forward little by little. Come out where they do not look for it and stab at their belly and breast, and they are sure to be swept as by the wind and unable to hold." And by this he settled Shu in the end. Not worn out means that the ground is empty, so that there is no care from the enemy and the going and the halting are in my own hands; and so one does not toil.

夫言空虛者，非止爲敵人不備也。但備之不嚴，守之不固，將弱兵亂，糧少勢孤，我整軍臨之，彼必望風自潰。是我不勞苦，如行無人之地。

In general, empty does not mean only that the enemy is unprepared. If only his preparation is not strict and his holding not firm, his general weak, his troops in disorder, his food scant and his momentum lonely, then when I put my troops in order and come up he is sure to fall apart of himself at the sight of the wind. This is the same as my going through ground where no one is without toil.

出所不意。

He comes out where they do not look for it.

曹公北征烏桓，謀臣郭嘉曰︰「兵貴神速，今千里襲人，輜重多，難以趨利。且彼聞之，得以爲備。不如留輜重，輕兵兼道以出，掩其不意。」公乃密出盧龍塞，直指單于庭。虜卒聞公至，惶怖合戰，大破之，斬蹋頓及名王已下。又，唐吐谷渾宼邊，以李靖爲西海道行軍大總管，輕途二千里，行空虛之地，平吐谷渾而還。故太宗曰︰「且李靖三千輕騎，深入虜庭，克復定襄，古今未有也。」

When Lord Cao struck the Wuhuan (烏桓) in the north, Guo Jia (郭嘉), his minister of plans, said, "Troops prize swiftness like a spirit's. Now we are to fall upon men a thousand li off, and with much baggage it is hard to run for the advantage. Besides, if they hear of it they can make their preparation. Better to leave the baggage behind and go with light troops, making two days' march in one, and fall upon them where they do not look for it." Lord Cao then went out secretly by the Lulong Pass (盧龍塞) and pointed straight at the Chanyu's court. The barbarians suddenly heard that Lord Cao had come, and in fear they closed with him; and he broke them utterly and cut down Tadun (蹋頓) and the named kings and those below them. Again, in the time of Tang, when the Tuyuhun (吐谷渾) came over the border, Li Jing (李靖) was made marching commander-in-chief of the Xihai road, went lightly two thousand li through empty ground, settled the Tuyuhun and came back. And so Taizong (太宗) said, "And Li Jing's going deep into the barbarian court with three thousand light horse and winning Dingxiang (定襄) back is a thing that has not been from of old until now."

掩其空虛，攻其無備，雖千里之征，人不疲勞。若鄧艾伐蜀，由陰平之徑，行無人之地七百餘里是也。

Fall upon the empty place and strike where he is unprepared, and though it be a battle of a thousand li the men are not worn out. Deng Ai (鄧艾), in striking Shu, going more than seven hundred li through ground where no one was along the narrow road of Yinping (陰平), is this.

無虞易取。

What is not troubled over is easy to take.

警其東，擊其西；誘其前，襲其後。後漢張步都劇，使弟藍守西安，又令別將守臨淄，去臨淄四十里，耿弇引軍營其間。弇視西安城小而堅，藍兵又精；臨淄名雖大，其實易攻。弇令軍吏治攻具，後五日攻西安，縱生口令歸。藍聞之，晨夜守城。至期，夜半，弇勒諸將蓐食，及明，至臨淄城下。護軍荀梁等爭之，以爲宜速攻西安。弇曰︰「西安聞吾欲攻，日夜爲備；臨淄出其不意，至必驚擾，吾攻之，一日必拔。拔臨淄，卽西安勢孤。所謂擊一得兩。」盡如其策。後漢末，朱雋擊黃中賊帥韓忠於宛。雋作長圍，起土山，以臨其城內。因鳴鼓攻其西南，賊悉衆赴之；雋自將精兵五千，掩其東北，乘城而入。忠乃退保小城，惶懼乞降。

Startle the east and strike the west; lure the front and fall upon the rear. In the time of the Later Han, Zhang Bu made Ju (劇) his capital and set his younger brother Zhang Lan (張藍) to hold Xi'an (西安), and set another general to hold Linzi (臨淄), forty li away. Geng Yan led his troops and drew up his lines between them. Geng Yan saw that Xi'an, though its wall was small, was firm, and that Zhang Lan's troops were nimble too, while Linzi was great in name but in truth easy to strike. Geng Yan had his officers make the engines of attack ready and said that in five days he would strike Xi'an, and let a captive go free to return. Zhang Lan heard of it and held his wall morning and evening. When the day came, in the middle of the night Geng Yan pressed his generals to eat at their places, and at daybreak he came beneath the wall of Linzi. Xun Liang (荀梁), the protector of the army (護軍), and the rest argued that Xi'an should be struck quickly. Geng Yan said, "Xi'an has heard that I mean to strike it and has made ready night and day; Linzi is where they do not look for it, and when I come they are sure to be startled into confusion, so that if I strike I shall take it in a day for certain. Take Linzi, and the momentum of Xi'an is at once left lonely. This is what is called striking one and getting two." And it all fell out by his plan. At the end of the Later Han, Zhu Jun (朱雋) struck Han Zhong (韓忠), chief of the Yellow Turban (黃巾) bandits, at Wan (宛). Zhu Jun drew a long ring about the place and raised an earthen hill to look down into the walls. Then he sounded his drums and struck the southwest, and the bandits ran there with their whole host. Zhu Jun himself led five thousand picked men, fell upon the northeast, climbed the wall and went in. Han Zhong then drew back to hold the inner wall, and in fear begged to surrender.

國家征上黨，王宰知劉稹恃天井之險，不爲固守之計。宰悉力攻奪而後守，稹失其險，終陷其巢穴也。

When the state struck Shangdang (上黨), Wang Zai (王宰) knew that Liu Zhen (劉稹) trusted only in the broken ground of Tianjing (天井) and had laid no plan to hold it firm. Wang Zai struck with all his strength and took it and then held it, and Liu Zhen, having lost his broken ground, saw his lair fall in the end.

言擊其南，實攻其北。

It means making as if to strike the south while in truth striking the north.

攻其虛也，謂將不能、兵不精、壘不堅、備不嚴、救不及、食不足、心不一爾。

It is striking where he is empty: that is, the general not able, the troops not nimble, the ramparts not firm, the preparation not strict, the rescue not coming up, the food not enough, and the heart not one.

善攻者，動於九天之上，使敵人莫之能備；莫之能備，則吾之所攻者，乃敵之所不守也。耿弇之克臨淄，朱雋之討黃巾，但其一端耳。

He who strikes well moves above the ninth heaven, so that the enemy cannot prepare. When he cannot prepare, the place I strike is just the place the enemy does not hold. Geng Yan's winning Linzi and Zhu Jun's striking the Yellow Turbans are only one corner of it.

不攻尚守，何況其所攻乎？漢太尉周亞夫擊七國於昌邑也，賊奔壁東南陬，亞夫使備其西北。俄而賊精卒攻西北，不得入，因遁走，追破之。

Even the place he does not strike is held; how much more the place he does strike. When Zhou Yafu, Grand Commandant of Han (漢), struck the seven states from Changyi, the enemy rushed at the southeast corner of his ramparts, and Zhou Yafu had the northwest made ready. Soon the enemy's picked troops struck the northwest but could not get in, and then fled; and he gave chase and broke them.

無慮敵不攻，慮我不守。無所不攻，無所不守，乃用兵之計備也。

Do not worry that the enemy will not strike; worry that I shall not be able to hold. That there is no place he does not strike and no place I do not hold is just the plan and the preparation of using troops.

賊擊我西，亦備乎東。

Though the enemy strike my west, I make the east ready as well.

守以實也。謂將能、兵精、壘堅、備嚴、救及、食足、心一爾。

It is holding with what is full: that is, the general able, the troops nimble, the ramparts firm, the preparation strict, the rescue coming up, the food enough, and the heart one.

善守者，藏於九地之下，使敵人莫之能測；莫之能測，則吾之所守者，乃敵之所不攻也。周亞夫擊東南而備西北，亦是其一端也。

He who holds well hides beneath the ninth earth, so that the enemy cannot reckon him. When he cannot reckon, the place I hold is just the place the enemy does not strike. Zhou Yafu's making the northwest ready against an enemy striking the southeast is also one corner of it.

情不泄也。

It means that nothing within leaks out.

善攻者，器械多也，東魏高歡攻鄴是也；善守，謹備也，周韋孝寬守晉州是也。

He who strikes well has many engines, and Gao Huan (高歡) of the Eastern Wei striking Ye (鄴) is this; holding well is being careful in preparation, and Wei Xiaokuan (韋孝寬) of Zhou (周) holding Jinzhou (晉州) is this.

攻取備禦之情不泄也。

The purpose of striking and taking, of preparing and blocking, does not leak out.

教令行，人心附，備守堅固，微隱無形，敵人猶豫，智無所措也。

When teaching and command are carried out, men's hearts cleave to you, preparation and holding are firm, and all is hidden and without shape, then the enemy hesitates and has nowhere to put his wits to use.

善攻者，機密不泄；善守者，周備不隙。

He who strikes well does not let the secret leak; he who holds well is ready all round and leaves no gap.

善攻者，待敵有可勝之隙，速而攻之，則使其不能守也；善守者，常爲不可勝，則使其不能攻也。云不知者，攻守之計不知所出耳。

He who strikes well waits for a gap to open in the enemy by which he may be beaten, and strikes quickly, so that he cannot hold. He who holds well keeps himself always such that he cannot be beaten, so that the enemy cannot strike. The saying "does not know" means only that he does not know where to lay his plan of striking and holding.

言攻守之謀，令不可測。

It means making the plan of striking and holding past reckoning.

夫守則不足，攻則有餘。所謂不足者，非力弱也，蓋示敵以不足，則敵必來攻，此是敵不知其所攻也；所謂有餘者，非力彊也，蓋示敵以有餘，則敵必自守，此是敵不知其所守也。情不外泄，積乎攻守者也。

In general, holding is falling short and striking is having to spare. What is called falling short is not weakness of strength: show the enemy that you fall short and the enemy is sure to come and strike, and this is the enemy not knowing where to strike. What is called having to spare is not strength of force: show the enemy that you have to spare and the enemy is sure to hold himself, and this is the enemy not knowing where to hold. That one's purpose does not leak outward is what is stored up in striking and holding.

言二遁用兵之奇正，攻守微妙，不可形於言說也。微妙神乎，敵之死生，懸形於我，故曰「司命」。

It means that the two Dunjia (二遁) cannot put into words the subtlety of the surprise and the straight (奇正) in using troops, or of striking and holding. It is subtle and wondrous, and the enemy's death and life hang upon me; and so he said *siming* (司命), the one who has life in his charge.

微者，靜也；神者，動也。靜者守，動者攻，敵之死生，悉懸於我，故如天之司命。

The hidden is stillness and the wondrous is movement. What is still is holding and what moves is striking. The enemy's death and life hang wholly upon me, and so it is as though Heaven had the charge of their lives.

言其微妙，所不可見也。言變化之形，倐忽若神，故能料敵死生，若天之司命也。

It means that his subtlety is what cannot be seen. The shapes of his changing come so suddenly that it seems wondrous, and so it means that he can reckon the enemy's death and life, as though Heaven had the charge of their lives.

無形則微密，不可得而窺；無聲則神速，不可得而知。

Where there is no shape he is hidden and seamless and cannot be spied out; where there is no sound he is wondrous and swift and cannot be known.

微密則難窺，神速則難應，故能制敵之命。

Hidden and seamless, he is hard to spy out; wondrous and swift, he is hard to answer; and so he can hold the enemy's life down.

武論虛實之法，至於神微，而後見成功之極也。吾之實，使敵視之爲虛；吾之虛，使敵視之爲實。敵之實，吾能使之爲虛；敵之虛，吾能知其非實。蓋敵不識吾虛實，而吾能審敵之虛實也。吾欲攻敵也，知彼所守者爲實，而所不守者爲虛，吾將避其堅而攻其脆，批其亢而擣其虛。敵欲攻我也，知彼所攻者爲不急，而所不攻者爲要。吾將示敵之虛，而鬬吾之實。彼示形在東，而吾設備於西。是故，吾之攻也，彼不知其所當守；吾之守也，敵不料其所當攻。攻守之變，出於虛實之法。或藏九地之下，以喻吾之守；或動九天之上，以比吾之攻。滅跡而不可見，韜聲而不可聞。若從地出天下，倐出間入，星耀鬼行，入乎無間之域，旋乎九泉之淵。微之微者，神之神者，至於天下之明目不能窺其形之微，天下之聦耳不能聽其聲之神。有形者至於無形，有聲者至於無聲。非無形也，敵人不能窺也；非無聲也，敵人不能聽也，虛實之變極也。善學兵者，通於虛實之變，遂可以入於神微之奧；不善者，案然尋微窮神，而泥其用兵之跡，不能泯其形聲，而至於聞見者，是不知神微之妙固在虛實之變也。三軍之衆，百萬之師，安得無形與聲哉？但敵人不能窺聽耳。

Sun Wu (孫武), discussing the way of the empty and the full, shows the end of achieving a work only after he has come to what is wondrous and hidden. He makes the enemy see my full as empty and my empty as full. He can make the enemy's full empty, and he can know that the enemy's empty is not full. For the enemy does not know my emptiness and fullness, while I can look into his. When I would strike the enemy, I know that the place he holds is full and the place he does not hold is empty, and so I avoid where he is firm and strike where he is soft, draw back from where he is strong and knock where he is empty. When the enemy would strike me, I know that the place he strikes is not the pressing one and that the place he does not strike is the vital one. I show the enemy an empty place and contend with my full. If he shows a shape in the east, I set my preparation in the west. And so when I strike, he does not know the place he ought to hold; and when I hold, the enemy cannot reckon the place he ought to strike. The changes of striking and holding come out of the way of the empty and the full. Hiding beneath the ninth earth is the figure of my holding; moving above the ninth heaven is the match for my striking. He wipes out his traces so that they cannot be seen, and covers his sound so that it cannot be heard. As though coming out of the earth and going beneath the heavens, he appears of a sudden and enters by a gap; he shines like the stars and walks like a spirit, entering where there is no gap and circling the deep pool of the ninth spring. It is the hidden of the hidden and the wondrous of the wondrous, until it comes to this, that the clearest eyes in the world cannot spy out the hiddenness of his shape and the clearest ears in the world cannot hear the wondrousness of his sound. What has shape comes to having no shape, and what has sound comes to having no sound. It is not that there is no shape, but that the enemy cannot spy it out; not that there is no sound, but that the enemy cannot hear it: the change of the empty and the full is at its utmost. He who learns troops well goes through the changes of the empty and the full and so can enter at last into the deep place of the wondrous and the hidden. He who learns them ill searches quietly for the hidden and digs for the wondrous, and yet is bound to the traces of using troops: he cannot wipe out his shape and his sound, and it comes to men hearing and seeing them. This is not knowing that the wonder of the wondrous and the hidden lies from the first in the change of the empty and the full. How should the host of the three armies and a million soldiers be without shape and sound? It is only that the enemy cannot spy them out or hear them.

攻守之術，微妙神密，至於無形之可覩，無聲之可聞，故敵人死生之命，皆主於我也。

The way of striking and holding is subtle and wondrous and seamless, until it comes to having no shape that may be seen and no sound that may be heard; and so the enemy's lives, their death and life alike, hang wholly upon me.

卒往進攻其虛懈，退又疾也。

Advance all at once and strike where they are empty and slack; and in withdrawing, be swift as well.

進者，襲空虛懈怠；退者，必輜重在先，行遠而大軍始退，是以不可追。後趙王石勒兵在葛陂，苦雨，欲班師於鄴，懼晉人躡其後。用張賓計，令輜重先行，遠而不可及也。此筌以「速」字爲「遠」者也。

Advancing is falling upon what is empty and slack; falling back is putting the baggage first without fail, and only after it has gone far does the main army begin to draw off, so that it cannot be chased. When Shi Le (石勒), king of the Later Zhao (後趙), had his troops at Gebei (葛陂), he was distressed by the long rains and meant to turn his army back to Ye, but feared that the men of Jin would follow on his heels. He used Zhang Bin's (張賓) plan and sent the baggage ahead, so that it was too far to be reached. Here Li Quan read the character for swift (速) as far (遠).

旣攻其虛，敵必敗；敗喪之後，安能追我？我故得以疾退也。

Once I have struck his empty place, the enemy is sure to be beaten; and beaten and undone, how should he chase me? And so I can draw off swiftly.

杜說非也。曹公之圍張繡也，城未拔、力未屈而去之，繡兵出襲其後，賈詡止之，繡不聽，果被曹公所敗。繡謂詡曰︰「公旣能知其敗，必能知其勝。」詡曰︰「復以敗卒襲之。」繡從之，曹公果敗，豈是敗喪之後不能追之哉？蓋言乘虛而進，敵不知所禦；逐利而退，敵不知所追也。

Du Mu's (杜牧) word is wrong. When Lord Cao had Zhang Xiu (張繡) ringed about, he left without having taken the wall and without having had his strength broken. Zhang Xiu meant to send troops out and fall upon his rear, and Jia Xu (賈詡) forbade it; but Zhang Xiu would not listen, and was indeed beaten by Lord Cao. Zhang Xiu said to Jia Xu, "Since you knew we should be beaten, you must know how we may win as well." Jia Xu said, "Fall upon him again with the beaten troops." Zhang Xiu followed his word, and Lord Cao was indeed beaten. How then should it be that one cannot be chased only after being beaten and undone? It means that when one advances riding the empty place the enemy does not know where to block, and when one draws off following the advantage the enemy does not know where to chase.

衝突其虛空也。

It is stabbing and dashing at the place where he is empty.

進乘其虛，則莫我禦；退因其弊，則莫我追。

Advance riding his empty place and there is none to block me; in drawing off, follow upon his wearing down and there is none to chase me.

兵進則衝虛，兵退則利速。我能制敵，而敵不能制我也。

When troops advance they stab at the empty place, and when they draw off swiftness is the advantage. I can hold the enemy down, and the enemy cannot hold me down.

對壘相持之際，見彼之虛隙，則急進而擣之，敵豈能禦我也？獲利而退，則速還壁以自守，敵豈能追我也？兵之情主速，風來電往，敵不能制。

When ramparts face each other and the two stand opposed, if I see a gap where they are empty I advance in haste and knock at it, and how should the enemy block me? When I have got the advantage and draw off, I go back swiftly to my ramparts and hold myself, and how should the enemy chase me? The purpose of troops makes swiftness first: come like the wind and go like the lightning, and the enemy cannot hold you down.

絶其糧道，守其歸路，攻其君主也。

Cut their grain road, hold the road of their return, and strike at their ruler.

我爲主，敵爲客，則絶其糧食，守其歸路；若我爲客，敵爲主，則攻其君主。司馬宣王攻遼東，直指襄平是也。

If I am the host and the enemy the guest, I cut the enemy's grain and hold the road of his going back. If I am the guest and the enemy the host, I strike his ruler. Sima Xuanwang, striking Liaodong, heading straight for Xiangping is this.

攻其要害。

He strikes the vital place.

曹公曰︰「絶糧道，守歸路，攻君主也。」晳謂敵若堅守，但能攻其所必救，則與我戰矣。若耿弇欲攻巨里以致費邑亦是也。

Lord Cao said, "Cut the road of his grain, hold the road of his going back, and strike his ruler." As I see it, though the enemy hold firm, if you can strike the place he must rescue he comes to fight you. Geng Yan's meaning to strike Juli and so drawing Fei Yi out is this too.

如魏將司馬宣王征公孫文懿，汎舟潛濟遼水，作長圍，忽棄賊而向襄平。諸將言︰「不攻賊，而作長圍，非所以示衆也。」宣王曰︰「賊堅營高壘，欲以老吾兵也。古人言曰︰敵雖高壘，不得不與我戰者，攻其所必救也。賊大衆在此，則窟穴虛矣。我直指襄平，必人懷內懼；懼而求戰，破之必矣。」遂整陳而過。賊見兵出其後，果邀之。宣王謂諸將曰︰「所以不攻其營，正欲致此，不可失也。」乃縱兵逆擊，大破之。三戰皆捷。唐馬燧討田悅，時軍糧少，悅深壁不戰。燧令諸軍持十日糧，進次倉口，與悅夾洹水而軍。李抱真、李芃問曰︰「糧少而深入，何也？」燧曰︰「糧少，利速戰。兵法︰善於致人，不致於人。今田悅與淄、青、兖三軍爲首尾，計欲不戰，以老我師。若分兵擊其左右，兵少未可必破，悅且來救，是前後受敵也。兵法所謂攻其必救，彼固當戰也。燧爲諸軍合而破之。」燧乃造三橋，道逾洹水，日挑戰。悅不敢出。恒州兵以軍少，懼爲燧所并，引軍合於悅。悅與燧明日復挑戰，乃伏兵萬人，欲邀燧。燧乃引諸軍半夜皆食，先雞鳴時，擊鼓吹角，潛師傍洹水，徑赴魏州，令曰︰「聞賊至，則止爲陳。」又令百騎吹鼓角，皆留於後，仍抱薪持火，待軍畢發，止鼓角，匿其旁，伺悅軍畢渡，焚其橋。軍行十數里，乃率淄、青、兖州步騎四萬餘人，踰橋掩其後，乘風縱火，鼓譟而進。燧乃坐甲，令無動，命前除草、斬荊棘，廣百步以爲陳。募勇力得五千餘人，分爲前列，以俟賊至。比悅軍至，則火止，氣乏，力少衰，乃縱兵擊之，悅軍大敗。悅走橋，橋已焚矣。悅軍亂，赴水，斬首二萬，淄、青軍殆盡。

When Sima Xuanwang, general of Wei, struck Gongsun Wenyi, he floated his boats and crossed the Liao in secret and was raising a long ring of works when he suddenly left the enemy and headed for Xiangping. His generals said, "Not to strike the enemy but only to raise a long ring is not what one should show troops." Xuanwang said, "The enemy has made his lines firm and his ramparts high to wear our troops out. The men of old said, 'What makes an enemy unable to help fighting you, though he raise his ramparts high, is that you strike the place he must rescue.' The enemy's great host is here, so his lair is empty. If I go straight for Xiangping, every man will bear fear in his heart; and when they fear and seek battle, breaking them is certain." So he put his lines in order and marched past. The enemy, seeing troops come out behind them, did indeed come out to meet him. Xuanwang said to his generals, "That I did not strike their lines was just to draw this out, and it must not be let slip"; and he loosed his troops, met them and struck, and broke them utterly. He fought three times and won every time. When Ma Sui (馬燧) of Tang struck Tian Yue (田悅), his grain was scant, and Tian Yue made his walls deep and would not fight. Ma Sui had all his armies carry ten days' food, went forward and halted at Cangkou (倉口), and drew up his lines with Tian Yue along the Huan (洹水). Li Baozhen (李抱眞) and Li Peng (李芃) asked, "Our food is scant; why go in deep?" Ma Sui said, "When food is scant, a quick battle is the advantage. The art of war says, 'Be good at drawing others in, and be not drawn in by others.' Now Tian Yue has made himself head and tail with the three commanderies of Zi (淄), Qing (靑) and Yan (兗), meaning not to fight but to wear our troops out. If I split my troops and strike his left and right, the troops are too few and are sure not to break him, and when Tian Yue comes to the rescue besides, we take the enemy front and rear. What the art of war calls striking the place he must rescue will make him unable not to fight. I shall join all my armies and break him." Ma Sui laid three bridges to open a road and crossed the Huan, and offered battle day after day, but Tian Yue could not come out. The troops of Hengzhou (恒州), being few in number, feared that Ma Sui would swallow them up and led their troops to join Tian Yue. Tian Yue settled to fight Ma Sui again the next day and hid ten thousand men to meet him. Ma Sui fed all his armies in the dead of night, and before the cocks crew beat his drums and blew his horns while he sent his troops secretly along the Huan straight for Weizhou (魏州), with the order, "If you hear that the enemy is coming, halt and draw up your lines." He also had a hundred horsemen beat drums and blow horns, and left them all behind, holding brushwood and carrying fire, to wait until the troops had all gone, then stop the drums and horns, hide beside the road, and watch for Tian Yue's troops to cross over and burn the bridges. When the troops had gone some ten li, Tian Yue led more than forty thousand foot and horse of Zi, Qing and Yan over the bridges and fell upon their rear, setting fires with the wind, beating drums and going forward with a great clamor. Ma Sui had his men sit in their armor and ordered them not to stir, and had the grass in front cut and the thorn trees cleared to make a place for his lines a hundred paces wide. He picked out the nimble and strong, got more than five thousand of them, told them off into the front rank, and waited for the enemy to come. By the time Tian Yue's troops arrived, the fires had died and their spirit was spent, so that their strength was a little broken; and he loosed his troops and struck, and Tian Yue's troops were utterly beaten. Tian Yue fled for the bridges, but the bridges were burnt already. Tian Yue's troops fell into confusion and leapt into the water; twenty thousand heads were taken, and the troops of Zi and Qing were all but wiped out.

我爲客，彼爲主，我兵彊而食少，彼勢弱而糧多，則利在必戰。敵人雖有金城湯池之固，不得守其險，而必來與我戰者，在攻其所顧愛，使之相救援也。若楚人圍宋，晉將救之，狐偃曰︰「楚始得曹，而新婚於衞；若伐曹、衞，楚必救之，則宋免矣。」從之而解。又，晉宣帝討公孫文懿，忽棄賊而走襄平，討其巢穴。賊果出邀之，遂逆擊，三戰皆捷，亦其義也。

If I am the guest and they the host, and my troops are strong but my food scant while they are weak in momentum but have much food, then the advantage lies certainly in fighting. Though the enemy have what is as firm as a wall of iron and a moat of boiling water, he cannot hold his broken ground and must come out to fight me; and this lies in striking the place the enemy looks to and holds dear, so making them go to one another's rescue. When the men of Chu ringed Song about and Jin meant to go to the rescue, Hu Yan (狐偃) said, "Chu has just got Cao and is newly married into Wei; strike Cao and Wei and Chu is sure to come to their rescue, and then Song is freed." They followed his word, and the siege was raised. Again, when Emperor Xuan of Jin (晉宣帝) struck Gongsun Wenyi, he suddenly left the enemy and ran for Xiangping and struck his lair. The enemy did indeed come out to meet him, and he met them at once and struck, and fought three times and won every time; and this too is that meaning.

軍不欲煩也。

It means not wishing to burden the troops.

拒境自守也。若入敵境，則用《天一遁甲》真人閉六戊之法，以刀畫地爲營也。

It is barring the border and holding oneself. When one has entered the enemy's border, one uses the way by which the True Man (眞人) of the *Tianyi Dunjia* (天一遁甲) shuts the Six Wu (六戊), drawing a line on the ground with a sword to make one's lines.

以物畫地而守，喻其易也。蓋我能戾敵人之心，不敢至也。

Drawing a line on the ground with some thing and holding it is said of how easy it is. Because I can turn the enemy's mind athwart, the enemy does not dare to come.

乖，戾也。戾其道，示以利害，使敵疑也。

Guai (乖) means to go athwart. Throw the road they are taking athwart, show them gain and harm, and make the enemy doubt.

乖，異也。設奇異而疑之，是以敵不可得與我戰。漢上谷太守李廣縱馬卸鞍，疑也。

Guai means to go athwart. He spreads out a plan that is not looked for so as to make the enemy doubt, and so the enemy cannot fight him. Li Guang (李廣), Grand Administrator of Shanggu (上谷太守) under Han, turning his horses loose and taking off their saddles is making the enemy doubt.

言敵來攻我，我不與戰，設權變以疑之，使敵人疑惑不決，與初來之心乖戾，不敢與我戰也。曹公爭漢中地，蜀先主拒之。時將趙雲守別屯，將數十騎輕出，卒遇大軍。雲且鬬且却。公軍追至，圍雲。入營，使大開門，偃旗息鼓。曹公軍疑有伏，引去。諸葛武侯屯於陽平，使魏延諸將并兵東下，武侯惟留萬人守城。候白司馬宣王曰︰「亮在城中，兵少力弱。」將士失色，亮時意氣自若，勑軍中悉卧旗息鼓，不得輒出，開四門，掃地却灑。宣王疑有伏，於是引去，趨北山。亮謂參佐曰︰「司馬懿謂吾有設伏，循山走矣。」宣王後知，頗以爲恨。曹公與呂布相持，公軍出收麥，布領衆卒至。公營止有千人出陳，半隱於堤下，呂布遲疑不敢進，曰︰「曹操多詐，勿入伏中。」遂引兵去。

It means that though the enemy come to strike me, I do not fight but spread out a plan of shifting as the moment serves, so as to make the enemy doubt, until he falls into perplexity and cannot decide and goes athwart the mind he came with, and does not dare come out and fight. When Lord Cao was contending for the land of Hanzhong (漢中), the Former Ruler (先主) of Shu stood against him. At that time the general Zhao Yun (趙雲), who was holding another camp, went out lightly with a few score horsemen and suddenly met the great army. Zhao Yun fought as he fell back, and Lord Cao's troops gave chase and ringed Zhao Yun about. Zhao Yun went into his camp, had the gates thrown wide open, laid the flags down and stopped the drums. Lord Cao's troops doubted that there were hidden troops and drew off. When Zhuge Wuhou (諸葛武侯) had drawn up his lines at Yangping (陽平), he had Wei Yan (魏延) and his other generals join their troops and go down east, keeping only ten thousand men himself to hold the city. Spies told Sima Xuanwang, "Zhuge Liang is within the city, but his troops are few and his strength weak." His generals and soldiers lost the color in their faces, but Zhuge Liang's manner was unmoved: he had all the flags in the camp laid down and the drums stopped, forbade any man to go out at will, opened the four gates, and had the ground swept and water sprinkled. Xuanwang doubted that there were hidden troops and drew off and went to the North Hill. Zhuge Liang said to his staff, "Sima Yi took it that I had troops hidden, and fled along the hills." Xuanwang learned of it afterwards and was bitterly sorry. When Lord Cao and Lü Bu (呂布) stood against each other, Lord Cao's troops had gone out to gather wheat, and Lü Bu came up suddenly with his host. There were only a thousand men in Lord Cao's camp; he sent them out and drew up his lines, with half of them hidden beneath the embankment. Lü Bu hesitated and did not dare go forward, and saying, "Cao Cao is full of deceits; do not go in among the hidden troops," he led his troops away.

《左傳》楚令尹子元伐鄭，入自純門，至於逵市，懸門不發。子元曰︰「鄭有人焉。」乃還。

In the *Zuo Commentary*, Ziyuan (子元), the chief minister (令尹) of Chu, struck Zheng (鄭), went in by the Chun Gate (純門) and came to the Kui market (逵市), but the portcullis was not let down. Ziyuan said, "There are men in Zheng," and went back.

置疑兵於敵惡之所，屯營於形勝之地，雖未修壘壍，敵人不敢來攻我也。

Set a doubtful force in the place the enemy shrinks from and draw up your lines on ground that lies well, and though you have not put rampart and moat in order the enemy will not dare come and strike you.

畫地，喻易也。乖其道而示以利，使其疑而不敢進也。

Drawing a line on the ground is said of how easy it is. Turn his road athwart and show him what looks like gain, so that the enemy doubts and does not dare go forward.

畫地，言易，且明制之必有道也。

Drawing a line on the ground is said of how easy it is, and it makes clear besides that there is always a way of holding the enemy down.

我爲主，彼爲客。我糧多而卒寡，彼食少而兵衆，則利在不戰。雖不爲營壘之固，敵必不敢來與我戰者，示以疑形，乖其所往也。若楚人伐鄭，鄭懸門不發，効楚言而出，楚師不敢進而遁。又，司馬懿欲攻諸葛亮，亮偃旗卧鼓，開門却灑，懿疑有伏兵，遂引而去，亦其義也。

If I am the host and they the guest, and my food is much but my troops few while they have scant food but many troops, then the advantage lies in not fighting. Though I have not made my lines and ramparts firm, the enemy does not dare come out and fight me, because I show a doubtful shape and so turn athwart what the enemy means to do. When the men of Chu struck Zheng, Zheng did not let the portcullis down and sent men out in the likeness of Chu's own speech, and the troops of Chu did not dare go forward but fled. Again, when Sima Yi meant to strike Zhuge Liang, Zhuge Liang laid his flags down, put his drums to rest, opened his gates and sprinkled water, and Sima Yi doubted that there were hidden troops and led his troops away; and this too is that meaning.

我專一而敵分散。

I am gathered into one and the enemy is scattered.

他人有形，我形不見，故敵分兵以備我。

The other's shape shows and mine is not to be seen, and so the enemy splits his troops to block me.

吾之正，使敵視以爲奇；吾之奇，使敵視以爲正，形人者也。以奇爲正，以正爲奇，變化紛紜，使敵莫測，無形者也。敵形既見，我乃合衆以臨之；我形不彰，彼必分勢以防備。

Making the enemy see my straight troops as surprise troops and my surprise troops as straight is making him show a shape. Taking the surprise for the straight and the straight for the surprise, and confounding the changes so that the enemy cannot reckon them, is having no shape. Once the enemy's shape has shown, I gather my host and stand against him; and when my shape does not show, they are sure to split their force to block me.

我料見敵形，審其虛實，故所備者少，專爲一屯。以我之專，擊彼之散卒，爲十共擊一也。

Because I measure out the enemy's shape and look into where he is empty and where full, the places I must guard are few, and I gather into a single camp. With my gathered soldiers I strike their scattered soldiers; it is ten striking one together.

離一爲十，我常以十分擊一分。

When the enemy breaks one into ten, I always strike one part with ten parts.

我專爲一，故衆；敵分爲十，故寡。

I am gathered into one and so am many; the enemy is divided into ten and so is few.

見敵虛實，不勞多備，故專爲一屯。彼則不然，不見我形，故分爲十處。是以我之十分，擊敵之一分也。故我不得不衆，敵不得不寡。

When I see where the enemy is empty and where full, I am not put to the trouble of guarding many places, and so I gather into a single camp. They cannot do so, for they do not see my shape, and so they are split into ten places. Thus I strike one part of the enemy with ten parts of my own. Therefore I cannot but be many, and the enemy cannot but be few.

約，猶少也。我深壍高壘，滅跡韜聲，出入無形，攻取莫測。或以輕兵健馬衝其空虛，或以彊弩長弓奪其要害。觸左履右，突後驚前。晝日誤之以旌旗，暮夜惑之以火鼓。故敵人畏懾，分兵防虞。譬如登山瞰城，垂簾視外，敵人分張之勢，我則盡知；我之攻守之方，敵則不測。故我能專一，敵則分離。專一者力全，分離者力寡。以全擊寡，故能必勝也。

Yue (約) is like few. I dig my moats deep and raise my ramparts high, wipe out my tracks and sheathe my sounds, so that my going out and coming in has no shape and my striking and seizing cannot be reckoned. Sometimes with light troops and sturdy horses I thrust at his empty places; sometimes with strong crossbows and long bows I seize the vital ground. I touch his left and tread on his right, thrust at his rear and startle his front. By day I mislead him with banners; by night I confuse him with fires and drums. So the enemy is afraid and divides his troops to stand guard. It is as though I climbed a mountain and looked down into his walls, or looked out from behind a hanging blind: the shape of the enemy's dividing and spreading out I know entirely, while the way of my own striking and guarding the enemy cannot reckon. Therefore I can gather into one and the enemy is divided. Gathered into one, strength is whole; divided, strength is little. Striking little strength with whole strength, I can be sure to win.

言約少而易勝。

This says that those he has to fight are few and so he wins easily.

以專擊分，則我所敵少也。

Striking divided soldiers with gathered soldiers, those I face are few.

多爲之形，使敵備己，其實攻者則無形也，故我專敵分矣。專則衆，分則寡。十攻一者，大約言耳。何氏同杜牧《註》。

He makes many shapes so that the enemy guards against him, while the side that actually strikes has no shape; and so I am gathered and the enemy divided. Gathered, one is many; divided, one is few. Striking one with ten is said only roughly. Master He's (何氏) note is the same as Du Mu's.

夫勢聚則彊，兵散則弱。以衆彊之勢，擊寡弱之兵，則衆力少而成功多矣。

When the situation is gathered one is strong, and when soldiers are scattered one is weak. If with a many and strong position one strikes few and weak soldiers, the strength spent is little and what is accomplished is much.

言舉動微密，情不可見，使彼知所出而不知吾所舉，知所舉而不知吾所集。

This says that his movements are subtle and close, so that his intent cannot be seen: they may know where I have come out but not what I mean to do, and know what I mean to do but not where I am gathering.

無形勢故也。

It is because there is no shape or situation shown.

敵不知，則處處爲備。

When the enemy does not know, he sets a guard in every place.

形藏敵疑，則分離其衆備我也，言少而易擊也。

If I hide my shape and the enemy doubts, they split their host to guard against me; this says that their numbers grow few and are easy to strike.

與敵必戰之地，不可使敵知之；知則并力得拒於我。曹公曰︰「形藏則敵疑。」

The ground where one must fight the enemy must not be let known to the enemy. If he knows it, he can join his strength and block me. Cao Gong said, "Hide the shape and the enemy doubts."

不能測吾車果何出，騎果何來，徒果何從，故分離其衆，所在輒爲備，遂致衆散而弱，勢分而衰，是以吾所與接戰之處，以大衆臨孤軍也。

Because he cannot reckon where my chariots will come out, where my horsemen will come, or where my foot soldiers will follow, the enemy divides his host and sets a guard in every place. So his host is scattered and grows weak and his position is split and declines, and at the place where I join battle I press a lone force with a great host.

言敵之所備者多，則士卒無不分散而少。

This says that when the places the enemy must guard are many, there is nowhere his soldiers are not divided and few.

所備皆寡也。

Every place he guards is short.

上所謂形藏敵疑，則分離其衆，以備我也。

As said above: hide the shape, and when the enemy doubts, they split their host to guard against me.

陳兵之地，不可令敵人知之；彼疑，則謂衆離而備我也。

The ground where troops are drawn up must not be let known to the enemy. This says that when the enemy doubts, he divides his host to guard against me.

所戰之地，不可令敵人知之。我形不泄，則左右、前後、遠近、險易，敵人不知，亦不知我何處來攻，何地會戰，故分兵徹衞，處處防備。形藏者衆，分多者寡，故衆者必勝也，寡者必敗也。

The ground of the fight must not be let known to the enemy. If my shape does not leak out, the enemy does not know my left and right, front and rear, far and near, rough ground and easy; nor does he know where I will come to strike or where we will meet and fight. So he divides his troops and posts them to hold places, guarding in every place. The side that hides its shape grows many, and the side divided into many grows few; the many are sure to win, and the few are sure to lose.

備人則我散，備我則彼分。

Guard against others and I am scattered; make others guard against me and they are divided.

敵分散而少者，皆先備人也；敵所以備己多者，由我專而衆故也。

The enemy is scattered and few because he first guards against others; and the places where the enemy must guard himself are many because I am gathered and many.

使敵愈備，則愈寡也。

The more you make the enemy guard, the fewer he becomes.

左右前後俱備，則俱寡。

Guard left and right, front and rear, and all are short.

何氏同諸《註》。

Master He's note is the same as the other notes.

左右前後，無處不爲備，則無處不兵寡也。所以寡者，爲兵分而廣備於人也；所以衆者，爲勢專而使人備己也。

If there is no place to left or right, front or rear, that he does not guard, then there is no place where his soldiers are not few. He becomes few because his soldiers are divided and he guards broadly against others; he becomes many because his position is gathered and he makes others guard against him.

以度量知空虛會戰之日。

By measuring and reckoning one knows where they are empty and the day of joining battle.

知戰之地，則舟車步騎之所便也。魏武以北土未安，捨鞍馬，仗舟楫，與吳越爭彊，是以有黃蓋之敗。吳王濞驅吳楚之衆，奔馳於梁鄭之間，此不知戰地日者。故《太一遁甲》曰︰「計法三門五將，主客成敗則可知也，於是千里會戰而勝。」

To know the ground of the fight is to know the places suited to boats and chariots, to foot soldiers and horsemen. Emperor Wu of Wei (魏武帝), while the northern lands were not yet settled, cast off saddle and horse and leaned on boats and oars to contend in strength with Wu and Yue (越); and so he suffered defeat at the hands of Huang Gai (黃蓋). King Pi of Wu (吳王濞) drove the hosts of Wu and Chu racing between Liang and Zheng; this is not knowing the ground and the day of the fight. So the *Taiyi Dunjia* says, "Use the method of reckoning by the three gates and the five generals, and the winning and losing of host and guest can be known; then though you meet and fight at a thousand li, you win."

宋武帝使朱齡石伐譙縱於蜀，宋武曰︰「往年，劉敬宣出內水向黃武，無功而退。賊謂我今應從外水來，而料我當出其不意，猶從內水來也。如此，必以重兵守涪城，以備內道，若向黃武，正墮其計。今以大衆自外取成都，疑兵向內水，此則制敵之奇也。」而慮此聲先馳，賊知虛實，別有函書，全封付齡石。函邊書曰︰「至白帝乃開。」諸軍未知處分所由。至白帝，發書曰︰「衆軍悉從外水取成都，臧熹、朱林於中水取廣漢，使羸弱乘高艦十餘，由內水向黃武。」譙縱果以重兵備內水，齡石滅之。

Emperor Wu of Song (宋武帝) sent Zhu Lingshi (朱齡石) to attack Qiao Zong (譙縱) in Shu. Emperor Wu said, "Last year Liu Jingxuan (劉敬宣) went out by the Inner Water (內水) and made for Huangwu (黃武), but withdrew without merit. The enemy will think I ought now to come by the Outer Water (外水), and yet will reckon that, to come out where he does not expect, I will still come by the Inner Water. If so, he is sure to hold Fucheng (涪城) with heavy troops and block the inner road; and to make for Huangwu would be to fall straight into his plan. Now to take Chengdu (成都) with the great host along the Outer Water, and send a feint force up the Inner Water — this is the strange stroke that masters the enemy." But fearing that word of this would run ahead and the enemy learn where he was empty and where full, he had a separate letter put in a box, sealed whole, and given to Zhu Lingshi. On the side of the box was written, "Open it on reaching Baidi (白帝)." The several armies did not know how they were to be divided and moved. On reaching Baidi the letter was opened, and it said, "Let all the armies take Chengdu along the Outer Water; let Zang Xi (臧熹) and Zhu Lin (朱林) take Guanghan (廣漢) by the Middle Water (中水); and let the weak ride ten and more tall warships and make for Huangwu by the Inner Water." Qiao Zong did indeed block the Inner Water with heavy troops, and Zhu Lingshi wiped him out.

杜《註》止言知戰之地，未敘知戰之日。我若伐敵，至期不得與我戰，敵來侵我，我必預備以應之。項羽謂曹咎曰︰「我十五日必定梁地，復與將軍會。」苟不知必戰之日，安能爲約？

Du Mu's note speaks only of knowing the ground of the fight and does not explain knowing the day of the fight. When I attack the enemy, he may not come out to fight me on the appointed day; and if the enemy comes to attack me, I am sure to make ready beforehand and meet him. Xiang Yu (項羽) said to Cao Jiu (曹咎), "In fifteen days I will surely settle the land of Liang and meet you again, General." If one did not know the day on which one must fight, how could one set such a term?

以度量知空虛，先知戰地之形，又審必戰之日，則可千里期會，先往以待之。若敵已先至，可不往以勞之。

By measuring and reckoning he knows where the enemy is empty; and if he first knows the shape of the ground of the fight and also looks into the day on which he must fight, then even at a thousand li he can set a day to meet, go first, and wait for the enemy. If the enemy has already arrived first, he can wear the enemy out by not going.

夫善戰者，必知戰之日，知戰之地。度道設期，分軍雜卒，遠者先進，近者後發，千里之會，同時而合，若會都市。其會地之日，無令敵知，知之則所備處少，不知則所備處多。備寡則專，備多則分。分則力散，專則力全。

One who is good at war always knows the day of the fight and the ground of the fight. He measures the roads and fixes the day, and divides and parcels out his troops: those far off set out first and those near set out later, so that their meeting at a thousand li is like gathering at one moment in a great market. The place and day of that meeting must not be let known to the enemy. If he knows, the places the enemy must guard are few; if he does not, they are many. When the places to guard are few he is gathered, and when they are many he is divided. Divided, his strength is scattered; gathered, his strength is whole.

若能度必戰之地，必戰之日，雖千里之遠，可剋期而與戰。

If he can reckon the ground where he must fight and the day on which he must fight, then though it be a thousand li away he can fix a day and fight.

必先知地利敵情，然後以兵法之度量，計其遠近，知其空虛，審敵趣應之所及戰期也。如是，則雖千里可會戰而破敵矣。故曹公曰「以度量知虛空會戰之日」者是也。

One must first know the advantage of the ground and the enemy's intent, and then, by the art of measuring and reckoning in the way of war, count the far and the near and know where he is empty, and look into the ground the enemy will hasten to meet him on and the day of the fight. Do this, and though it be a thousand li one can meet and fight and break the enemy. So what Cao Gong said, "By measuring and reckoning one knows where they are empty and the day of joining battle," is just this.

凡舉兵伐敵，所戰之地，必先知之。師至之日，能使敵人如期而來，以與我戰。知戰地日，則所備者專，所守者固，雖千里之遠可以赴戰。若蹇叔知晉人禦師必於崤，是知戰地也；陳湯料烏孫圍兵五日必解，是知戰日也。又若孫臏要龐涓於馬陵，度日暮必至是也。

Whenever troops are raised to attack an enemy, the ground of the fight must be known first. On the day the army arrives, he can make the enemy come as appointed and fight with him. Knowing the ground and the day of the fight, his guarding is gathered in one place and his holding is firm, so that though it be a thousand li away he can go forward to the fight. Jian Shu (蹇叔) knowing that the men of Jin would surely block the army at Xiao (崤) was knowing the ground of the fight; Chen Tang (陳湯) reckoning that the siege by the Wusun (烏孫) would surely be lifted in five days was knowing the day of the fight. So too was Sun Bin waiting for Pang Juan (龐涓) at Maling and reckoning that he would surely arrive at dusk.

《管子》曰︰「計未定而出兵，則戰而自毁也。」

The *Guanzi* (管子) says, "Send out troops before the reckoning is settled, and you will fight and bring yourself to ruin."

敵已先據形勢之地，己方趣利欲戰，則左右前後疑惑進退，不能相救，況數十里之間也？

If the enemy has already taken ground of good lie first and I would chase advantage and fight, then left and right, front and rear fall into doubt whether to advance or withdraw and cannot save one another. How much more so across tens of li?

不能救者，寡也。左右前後尚不能救，況遠乎？

They cannot save one another because they are few. If even left and right, front and rear cannot save one another, how much less the far parts?

不知敵人何地會兵，何日接戰，則所備者不專，所守者不固；忽遇勍敵，則倉遽而與之戰，左右前後猶不能相援，又況首尾相去之遼乎？

If he does not know in what place the enemy gathers his troops and on what day they will close, his guarding is not gathered in one place and his holding is not firm. Meeting a strong enemy of a sudden, he fights in a flurry, and left and right, front and rear cannot help one another; how much less when head and tail are far apart?

越人相聚，紛然無知也。或曰︰吳、越，讎國也。

The men of Yue are gathered together, but they are in disorder and know nothing. Some say instead: Wu and Yue were enemy states.

越，過也。不知戰地及戰日，兵雖過人，安能知其勝敗乎？

Yue (越) means to exceed. If one does not know the ground of the fight and the day of the fight, then though his soldiers exceed another's in number, how can he know his winning or losing?

孫子爲吳王闔閭論兵，吳與越讎，故言越；謂過人之兵，非義也。

Sunzi (孫子) was discoursing on war to King Helü of Wu, and Wu was the enemy of Yue, and so he spoke of Yue. To take it as meaning soldiers more numerous than another's does not fit the sense.

不知戰地，不知戰日，士衆雖多，不能制勝敗之政，亦何益也？

If one does not know the ground of the fight and does not know the day, then however many his soldiers he cannot master the matter of winning and losing; so what does it add?

吳、越，敵國也。言越人雖多，亦當爲我分之而寡也。

Wu and Yue were enemy states. This says that however many the men of Yue, if I divide them they become few.

此武相時料敵也。言越兵雖多，苟不善相救，亦無益於勝敗之數。

This is Sun Wu looking at the time and reckoning the enemy. It says that however many the soldiers of Yue, if they are not good at saving one another they add nothing to the count of winning and losing.

「吾」字作「吳」，字之誤也。吳、越鄰國，數相侵伐，故下文云「吳人與越人相惡也」。言越國之兵雖曰衆多，但不知戰地、戰日，當分其勢而弱也。

Writing the character "I" (吾) as "Wu" is a mistake in the character. Wu and Yue were neighboring states and often attacked each other, and so the text below says, "The men of Wu and the men of Yue hate each other." It says that though the soldiers of the state of Yue be called many, if they do not know the ground and the day of the fight their position will be divided and weak.

爲勝在我，故言可爲也。

Making victory rests with me, and so he says it can be made.

若使敵不知戰地、期日，我之必勝可常有也。

If the enemy is kept from knowing the ground of the fight and the appointed day, I can always have a sure victory.

梅堯臣同杜牧《註》。

Mei Yaochen's (梅堯臣) note is the same as Du Mu's.

王晳、何氏同孟氏《註》。

Wang Xi's and Master He's notes are the same as Master Meng's note.

爲勝在我故也。《形篇》云「勝可知而不可爲」，今言「勝可爲」者何也？蓋《形篇》論攻守之勢，言敵若有備，則不可必爲也，今則主以越兵而言，度越人必不能知所戰之地日，故云「可爲」也。

It is because making victory rests with me. The *Shape* chapter (形篇) says, "Victory can be known but cannot be made," and here it says, "Victory can be made" — why? The *Shape* chapter discusses the situation of attack and defense, and says that if the enemy has made ready it cannot be made a certainty; here he speaks with the soldiers of Yue in view, and reckoned that the men of Yue would surely not be able to know the ground and the day of the fight, and so he says it "can be made."

以下四事度量之，敵兵雖衆，使其不能與我鬬勝也。

Reckoning by the four matters below, however many the enemy's soldiers, they are kept from contending with me for victory.

敵雖多兵，我能多設變詐，分其形勢，使不能併力也。

Though the enemy has many soldiers, I set out many shifting and deceiving stratagems and divide his position, so that he cannot join his strength.

敵雖衆多，不知己之兵情，常使急自備，不暇謀鬬。

However many the enemy, if he does not know the intent of my troops he is always hurriedly guarding himself and has no leisure to plan a fight.

苟能寡，何有鬬？

If one can make them few, what fight is there?

多益不救，奚所恃而鬬？

Though they are many they cannot save one another; on what would they rely to fight?

分散其勢，不得齊力同進，則焉能與我爭？

Scatter his position so that he cannot gather his strength evenly and advance together, and how could he contend with me?

用兵者，取勝之法，可制《太一遁甲》「五將」之計，以定關格掩迫之數，得失可知也。

For one who uses troops, the method of gaining victory is this: use the reckoning of the "five generals" in the *Taiyi Dunjia*, and when the numbers of guan-ge (關格, blocking and barring) and yan-po (掩迫, covering and pressing) are fixed, the gains and losses can be known.

策度敵情，觀其施爲，則計數可知。

Reckon and measure the enemy's intent and watch what he does, and his reckoning can be known.

樽俎帷幄之間，以策籌之，我得彼失之計皆先知也。

Reckoning with counting rods between the wine cup and the carving board, inside the tent, one knows beforehand every plan by which I gain and they lose.

策度敵情，觀其所施，計數可知。

Reckon and measure the enemy's intent and watch what he sets out, and his reckoning can be known.

彼得失之計，我以算策而知。

Their plans of gain and loss I know by reckoning and counting.

策其敵情，以見得失之數。

He reckons the enemy's intent and so sees the number of gains and losses.

籌策敵情，知其計之得失，若薛公料黥布之三計是也。

He reckons the enemy's intent and knows the gains and losses of his plans. Duke Xue (薛公) reckoning the three plans of Ying Bu (黥布) is this.

候望雲氣、風鳥、人情，則動靜可知也。王莽時，王尋征昆陽，有雲氣如壞山，當營而墜，去地數丈，而光武知其必敗。梁王僧辯營上有如堤之氣，侯景知其必勝。風鳥，貪犲之類也。此筌以「作」字爲「候」字者也。

By watching the cloud vapors, the winds and birds, and men's hearts, moving and resting can be known. In Wang Mang's time, when Wang Xun (王尋) attacked Kunyang (昆陽), a cloud vapor like a crumbling mountain fell over the camp and came down to within a few fathoms of the ground, and Guangwu knew that Wang Xun would surely be beaten. When over the camp of Wang Sengbian (王僧辯) of Liang there was a vapor like a dike, Hou Jing (侯景) knew that he himself would surely win. Winds and birds are such things as the tanchai (貪犲). Here Li Quan takes the character "stir" (作) as the character "watch" (候).

作，激作也。言激作敵人，使其應我，然後觀其動靜理亂之形也。魏武侯曰︰「兩軍相當，不知其將，如何？」吳起曰︰「令賤勇者將銳而擊，交合而北，北而勿罰，觀敵進退，一坐一起，其政以理，奔北不追，見利不取，此將有謀。若其悉衆追北，旗幡雜亂，行止縱橫，貪利務得，若此之類，將令不行，擊而勿疑。」

Zuo (作) is stirring up. This says that one stirs the enemy up so that he answers me, and then watches the shape of his moving and resting, his order and his disorder. Marquis Wu of Wei (魏武侯) asked, "When two armies face each other and I do not know their general, what then?" Wu Qi (吳起) said, "Have a man of low rank and daring lead picked troops to strike, and when they have closed let them flee; and do not punish them for fleeing, but watch the enemy's advancing and withdrawing, his sitting down and rising up. If his governance accords with reason, so that he does not chase those who flee and does not take an advantage he sees, then the general has a plan. But if he drives his whole host to chase the fleeing, his flags and banners in confusion, his going and halting at random, coveting advantage and bent on getting it — with such as these the general's orders do not run, so strike him without doubt."

作，爲也。爲之利害，使敵赴之，則知進退之理也。

Zuo is making. Make an advantage and a harm so that the enemy hastens toward it, and one knows the pattern of his advancing and withdrawing.

善覘候者，必知其動靜之理。

One who is good at spying and watching is sure to know the pattern of his moving and resting.

喜怒動作，察其舉止，則情理可得。故知動靜權變，爲其勝負也。

By watching how he bears himself in his joy and anger and his movements, his intent and its pattern can be grasped. So one knows his moving and resting and his shifting with circumstance, and makes of it his winning or losing.

彼動靜之理，因我所發而見。

The pattern of their moving and resting shows itself through what I have stirred.

候其理當動以否。

He watches whether the pattern is such that he ought to move or not.

發作久之，觀其喜怒，則動靜之理可得而知也。若晉文公拘宛春，以怒楚將子玉，子玉遂乘晉軍，是其躁動也。諸葛亮遺巾幗婦人之飾，以怒司馬宣王，宣王終不出戰，此是其安靜也。

Stirring him up over a long while and watching his joy and anger, the pattern of his moving and resting can be known. Duke Wen of Jin (晉文公) held Wan Chun (宛春) in custody to anger Ziyu (子玉), the general of Chu, and Ziyu thereupon fell upon the army of Jin; this was moving in haste. Zhuge Liang (諸葛亮) sent a woman's head cloth and ornaments to anger Sima Xuanwang, but Xuanwang would not come out to fight to the end; this was staying still.

夫破陳設奇，或偃旗鼓，形之以弱；或虛列竈火幡幟，形之以彊。投之以死，致之以生，是以死生因地而成也。韓信下井陘，劉裕過大峴，則其義也。

In breaking a battle line and setting out strange strokes, one may lay down flags and drums to show a shape of weakness, or spread out empty stove fires and banners to show a shape of strength. One may throw them into a place of death or lead them to a place of life, for death and life are brought about according to the ground. Han Xin going down to Jingxing (井陘) and Liu Yu (劉裕) crossing Daxian (大峴) are that meaning.

死生之地，蓋戰地也。投之死地必生，置之生地必死。言我多方誤撓敵人，以觀其應我之形，然後隨而制之，則死生之地可知也。

The ground of death and life is the ground of the fight. Throw them into a place of death and they are sure to live; set them in a place of life and they are sure to die. This says that I mislead and shake the enemy in many ways so as to watch the shape of his answering me, and then press him accordingly; so the ground of death and life can be known.

敵人旣有動靜，則我得見其形。有謀者，所處之地必生；無謀者，所投之地必死也。

Once the enemy moves or rests, I can see his shape. For one who has a plan, the ground he holds is sure to be a place of life; for one who has none, the ground he is thrown into is sure to be a place of death.

形相敵情，觀其所據，則地形勢生死可得而知。

Looking at the enemy's intent by his shape and seeing the place he holds, the shape and lie of the ground and its death and life can be known.

見所理兵形，則可知其死所。

Seeing the shape in which his troops are ordered, one can know his place of death.

彼生死之地，我因形見而識。

Their ground of death and life I know through the showing of a shape.

何氏同杜牧《註》。

Master He's note is the same as Du Mu's.

形之以弱，則彼必進；形之以彊，則彼必退。因其進退之際，則知彼所據之地死與生也。上文云「善動敵者，形之，敵必從之」是也。死地，謂傾覆之地；生地，謂便利之地。

Show a shape of weakness and they are sure to advance; show a shape of strength and they are sure to withdraw. By the moment of their advancing and withdrawing one knows whether the ground they hold is a place of death or of life. What the text above said, "One who is good at moving the enemy shows him a shape, and the enemy is sure to follow it," is this. A place of death means ground where one is overturned; a place of life means ground that is easy and advantageous.

角，量也。

Jiao (角) means to measure.

角，量也。量其力精勇，則虛實可知也。

Jiao is measuring. Measure whether his strength is keen and quick, and where he is empty and where full can be known.

角，量也。言以我之有餘，角量敵人之有餘；以我之不足，角量敵人之不足。《管子》曰︰「善攻者，料衆以攻衆，料食以攻食；食不存不攻，備不存不攻。」司馬宣王伐遼東，司馬陳珪曰︰「昔攻上庸，八部並進，晝夜不息，故能一旬之半，拔堅城，斬孟達；今者遠來，而更安緩，愚切惑焉。」王曰︰「孟達衆少，而食支一年；吾將四倍於達，而糧不淹一月。以一月圖一年，安可不速？以四擊一，正命半解，猶當爲之。是以不計死傷，與糧競也。今賊衆我寡，賊飢我飽，雨水乃爾，功力不設，賊糧垂盡，當示無能以安之。」旣而雨止，晝夜攻之，竟平遼東。

Jiao is measuring. This says that with what I have in excess I measure what the enemy has in excess, and with what I fall short in I measure what the enemy falls short in. The *Guanzi* says, "One who is good at attacking reckons hosts to attack hosts and reckons provisions to attack provisions. If provisions are not in hand he does not attack; if preparations are not in hand he does not attack." When Sima Xuanwang attacked Liaodong, the marshal Chen Gui (陳珪) said, "In the past, in attacking Shangyong, the eight divisions advanced together and did not rest day or night, and so in half of ten days we took a firm walled city and cut down Meng Da (孟達). Now we have come far and yet are the more at ease; I am much bewildered." The prince said, "Meng Da's host was small but his provisions would hold a year, and my troops were four times Da's but our provisions would not last a month. To plan against a year with a month — how could we not be quick? Striking one with four, even losing half we still had to do it. So we did not reckon the dead and wounded, but raced against the provisions. Now the enemy is many and we are few, the enemy hungry and we full; and with the rains as they are, our strength cannot be put forth. The enemy's provisions are running out, and we should show ourselves unable, so as to set him at ease." Presently the rain stopped, and he attacked day and night, and in the end settled Liaodong.

彼有餘不足之處，我以角量而審。

Where they are in excess and where they fall short I look into by testing and measuring.

角，謂相角也。角彼我之力，則知有餘不足之處，然後可以謀攻守之利也。此而上亦所以量敵知戰。

Jiao means testing against each other. Test their strength against mine and one knows where there is excess and where shortfall, and then can plan the advantage of attack and defense. Up to this point, too, is the way of measuring the enemy and knowing the fight.

有餘，彊也；不足，弱也。角量敵形，知彼彊弱之所。唐太宗曰︰「凡臨陳，常以吾彊對敵弱，常以吾弱對敵彊。」苟非角量，安得知之？

Excess is strength and shortfall is weakness. By testing and measuring the enemy's shape one knows the places where he is strong and where weak. Emperor Taizong of Tang said, "Whenever I come to a battle line, I always set my strong against the enemy's weak, and always set my weak against the enemy's strong." Without testing and measuring, how could one know it?

形敵之妙，入於無形。間不可窺，智不可謀，是謂形也。

The subtlety of showing the enemy a shape enters into having no shape. A spy cannot peer in and wisdom cannot plan against it; this is what is called shape.

此言用兵之道，至於臻極，不過於無形。無形，則雖有間者深來窺我，不能知我之虛實。彊弱不泄於外，雖有智能之士，亦不能謀我也。

This says that the way of using troops, carried to its height, goes no further than having no shape. With no shape, though a spy come deep in and peer at me, he cannot know where I am empty and where full. Strength and weakness do not leak outward, so that though there be men of wisdom and ability, they cannot plan against me.

兵本有形，虛實不露，是以無形，此極致也。雖使間者以情釣，智者以謀料，可得乎？

An army has a shape of its own, but where it is empty and where full is not exposed, and so it has no shape; this is reaching the height. Though one set a spy to angle for his intent and a wise man to reckon with plans, could they get it?

制兵形於無形，是謂極致，孰能窺而謀之哉？

He handles the army's shape in having no shape; this is called the height. Who could peer in and plan against it?

行列在外，機變在內，因形制變，人難窺測，可謂神微。

The ranks and files are outside, while shifting with the moment is within; and if one handles his shifting according to shape, men can hardly peer in and reckon him. It may be called divine and subtle.

始以虛實形敵，敵不能測，故其極致，卒歸於無形。旣無形可覩，無迹可求，則間者不能窺其隙，智者無以運其計。

At first he shows the enemy shapes of emptiness and fullness, and the enemy cannot reckon him; so at its height it comes back in the end to having no shape. With no shape to be seen and no track to be sought, a spy cannot peer at his gaps and a wise man has nowhere to work his plans.

因敵形而立勝。

Set up victory according to the enemy's shape.

錯，置也。設形險之勢，因士卒之勇，而取勝焉。軍事尚密，非衆人之所知也。

Cuo (錯) is setting down. He sets out a position of rough shape and gains victory through the daring of his soldiers. Matters of war hold secrecy high, and are not what the crowd can know.

窺形可置勝敗，非智者不能，固非衆人所能得知也。

To peer at a shape and be able to set down winning and losing is not possible but for a wise man, and so is certainly not what the crowd can come to know.

衆知我能置勝矣，不知因敵之形。

The crowd knows that I can set victory down, but does not know that it goes by the enemy's shape.

因敵置勝，衆不能知。

He sets victory down according to the enemy, and the crowd cannot know it.

因敵變動之形以置勝，非衆人所能知。

He sets victory down according to the shape of the enemy's shifting and moving, and it is not what the crowd can know.

不以一形之勝萬形。或曰︰不備知也。制勝者，人皆知吾所以勝，莫知吾因敵形制勝也。

One does not conquer ten thousand shapes with a single shape. Some say instead: it means they do not know it all. As for the one who makes victory, everyone knows how I won, but none knows that I made the victory by following the enemy's shape.

戰勝，人知之；制勝之法幽密，人莫知。

That he won the battle, men know; but the method of making victory is deep and secret, and men do not know it.

言已勝之後，但知我制敵人，使有敗形，本自於我，然後我能勝之也。上文云︰「近而示之遠，遠而示之近，利而誘之，亂而取之，實而備之，彊而避之，怒而撓之，卑而驕之，佚而勞之，親而離之。」斯皆制勝之道，人莫知之也。

This says that after the victory is won, they know only that my pressing the enemy so that he had a shape of defeat began from me, and that only then could I win. The text above said, "When near, show him you are far; when far, show him you are near; lure him with advantage; take him in his disorder; when he is solid, make ready against him; when he is strong, avoid him; anger him and shake him; be humble and make him haughty; when he is at ease, wear him out; when he is close-knit, split him apart." These are all the way of making victory, and men do not know it.

人但知我勝敵之善，不能知我因敵之敗形。

Men know only the excellence with which I beat the enemy, and cannot know that I went by the enemy's shape of defeat.

知得勝之跡，而不知作勝之象。

They know the track by which victory was gained, but not the figure in which victory was made.

若韓信背水拔幟是也。人但見水上軍殊死戰，不可敗；及趙軍驚亂遁走，不知吾能制使之然者以何道也。

Han Xin fighting with the river at his back and pulling up the banners is this. Men saw only that the troops at the water's edge fought to the death and could not be beaten, and that the army of Zhao took fright, fell into disorder and fled; they did not know by what way I was able to make it so.

立勝之迹，人皆知之，但莫測吾因敵形而制此勝也。

The track in which victory was set up, men all know; but they cannot reckon that I made this victory by going with the enemy's shape.

不重復動而應之也。

He does not repeat the same thing over again, but answers each occasion as it comes.

不復前謀以取勝，隨宜制變也。

He does not seek to gain victory again by a stratagem used before, but shifts and handles it as is fitting.

敵每有形，我則始能隨而應之以取勝。

Whenever the enemy comes to have a shape, I can then follow it and answer it and so gain the victory.

死官也。

It is a dead rule.

應敵形而制勝，乃無窮。

Because he answers the enemy's shape and so makes victory, it has no end.

不執故態，應形有機。

He does not hold on to his old bearing, and in answering a shape there is a moment to seize.

夫制勝之理惟一，而所勝之形無窮也。

The principle of making victory is one only, but the shapes by which one wins are without end.

已勝之分，不再用也。敵來斯應，不循前法，故不窮。

The measure by which he has already won he does not use again. When the enemy comes he answers at once, and does not follow the method used before, and so it has no end.

已勝之後，不復更用前謀，但隨敵之形而應之，出奇無窮也。

After he has won, he does not use the stratagem of before again, but answers only according to the enemy's shape; so strange strokes come forth without end.

兵之形勢如水流，遲速之勢無常也。

The shape and lie of an army is like the flow of water: the lie of its slowness and swiftness is never constant.

性也。

It is its inborn nature.

利也。

It is following advantage.

水趨下則順，兵擊虛則利。

When water runs to the low it goes with its course; when an army strikes the empty it gains advantage.

因地之下。

It follows the low places of the ground.

順高下也。

It follows what is high and what is low.

方圓斜直，因地而成形。

Square and round, slanting and straight — it takes its shape from the ground.

不因敵之勢，吾何以制哉？夫輕兵不能持久，守之必敗；重兵挑之必出。怒兵辱之，彊兵緩之，將驕宜卑之，將貪宜利之，將疑宜反間之，故因敵而制勝。

If I do not follow the enemy's shape and disposition, by what shall I set my victory? Light troops cannot hold out long, so if they defend they must lose. Heavy troops, once provoked, must come out. Troops that are angry, shame them; troops that are strong, slacken them; if the general is haughty, bring him low; if the general is greedy, show him advantage; if the general is suspicious, use a fanjian (反間), a spy who sets the enemy apart. Therefore one follows the enemy in setting victory.

因敵之虛也。

It follows the enemy's empty places.

見敵盛衰之形，我得因而立勝。

I look at the shape of the enemy's flourishing and waning, and set up my victory according to it.

言水因地之傾側而制其流，兵因敵之虧闕而取其勝者也。

This says that water follows the slope of the ground in setting its course, and an army follows what is lacking and empty in the enemy in gaining its victory.

隨虛實也。

It follows the empty and the full.

謂隄防疏導之也。

This speaks of damming it with banks and opening a channel to lead it.

因敵彊弱而成功。

He follows the enemy's strength and weakness and so accomplishes his work.

虛實彊弱，隨敵而取勝。

Empty and full, strong and weak — he looks at these according to the enemy and so gains victory.

應敵爲勢。

He answers the enemy and makes that his momentum.

敵有變動，故無常勢。

Because the enemy has its shifting and moving, there is no fixed momentum.

因地爲形。

It follows the ground and makes that its shape.

兵有變化，地有方圓。

An army has its changes, and the ground has its square and its round.

地有高下，故無常形。

Because the ground has high and low, there is no fixed shape.

勢盛必衰，形露必敗，故能因敵變化，取勝若神。

When momentum flourishes it must wane; when the shape is shown it must be defeated. So when one changes with the enemy, the victory seems divine.

能知此道，謂之神兵也。

If one can know this way, it is called a wondrous army.

兵之勢，因敵乃見，勢不在我，故無常勢。如水之形，因地乃有，形不在水，故無常形。水因地之下，則可漂石；兵因敵之應，則可變化如神者也。

The momentum of an army appears according to the enemy, and the momentum is not in me, so there is no fixed momentum. The shape of water too arises according to the ground, and the shape is not in the water, so there is no fixed shape. When water follows the low places of the ground, it can carry stones away; when an army follows the enemy's answering, its changes can reach as far as the wondrous.

隨而變化，微不可測。

He changes according to the enemy, so subtly that it cannot be fathomed.

兵有常理，而無常勢；水有常性，而無常形。兵有常理者，擊虛是也；無常勢者，因敵以應之也。水有常性者，就下是也；無常形者，因地以制之也。夫兵勢有變，則雖敗卒，尚復可使擊勝兵，況精銳乎？

An army has a fixed principle but no fixed momentum; water has a fixed nature but no fixed shape. That an army has a fixed principle means that it strikes the empty; that it has no fixed momentum means that it answers according to the enemy. That water has a fixed nature means that it goes to the low; that it has no fixed shape means that it is settled by the ground. If there is change in an army's momentum, even a beaten army can be made to strike a winning army again — how much more sharp and chosen troops?

行權應變在智略；智略不可測，則神妙者也。

To follow the circumstances and answer their changes rests on scheming and wisdom. When the scheming and the wisdom cannot be fathomed, that is the wondrous.

兵勢已定，能因敵變動，應而勝之，其妙如神。

Even when the army's momentum is already settled, if he can answer the enemy's shifting and moving and so win, his subtlety is as the wondrous.

五行更王。

The five phases flourish each in turn.

迭相克也。

By turns they press one another down.

四時迭用。

The four seasons are used each in turn.

迭相代也。

By turns they give way to one another.

兵無常勢，盈縮隨敵。

Troops have no fixed momentum; their waxing and waning follows the enemy.

五行者，休囚王相遞相勝也。四時者，寒暑往來無常定也。日月者，周天三百六十五度四分度之一。百刻者，春秋二分，則日夜均；夏至之日，晝六十刻、夜四十刻；冬至之日，晝四十刻、夜六十刻，長短不均也。月初爲朔，八日爲上弦，十五日爲望，二十四日爲下弦，三十日爲晦，則死生義也。孫子以爲五行、四時、日月盈縮無常，況於兵之形變，安常定也？

The five phases are xiu (休, resting), qiu (囚, shut in), wang (王, reigning) and xiang (相, assisting), which overcome one another in turn. The four seasons are the coming and going of cold and heat, with nothing fixed in them. The sun and the moon circle the heavens in three hundred sixty-five and a quarter degrees. Of the hundred ke (刻, marks) of a day: at the spring and autumn equinoxes day and night are even; at the summer solstice the day is sixty ke and the night forty; at the winter solstice the day is forty ke and the night sixty — so long and short are not even. The first day of the month is called the new moon (朔), the eighth the upper quarter (上弦), the fifteenth the full moon (望), the twenty-fourth the lower quarter (下弦), and the thirtieth the dark of the moon; this is the meaning of waning and waxing. Sunzi saw that the five phases, the four seasons, and the sun and the moon are not constant in their waxing and waning; how much less can there be anything fixed in the changing of an army's shape?

皆所以象兵之隨敵也。

All of these picture how an army follows the enemy.

皆喻兵之變化非一道也。

All of these are likenesses for how the changes of an army are not of one single way.

言五行之休王，四時之代謝，日月之盈昃，皆如兵勢之無定也。

This says that the waning and flourishing of the five phases, the turning away of the four seasons, and the waxing and waning of the sun and the moon are all like the army's momentum having nothing fixed in it.