The Art of War

The Art of War is probably the most famous military treatise in the world. It has traditionally been ascribed to the Chinese general and strategist Sun Wu, who lived approximately 2,500 years ago during China’s Spring and Autumn period. The work places particular emphasis on large-scale infantry manoeuvres and is known for its canny, realistic approach to warfare. Its author views open war as a highly disruptive, economically draining endeavour to be resorted to only when other means have failed. Since war is so bad, then, the work focuses on winning as quickly, easily, and decisively as possible, with minimal detriment to the state’s resources. It is above all a practical rather than a philosophical guide.

The Art of War has had a significant influence on much military thinking through the years, and continues to be held in high regard by militaries (and businesses) in our own era.

I personally recommend The Art of War as a good introductory text for students of classical Chinese, because of its concision, straightforward grammar and vocabulary, and practical applicability.

Chapter 1: Strategy

Master Sun said:

Warfare is a matter of great importance to the state. It is the ground of life and death, the road to survival or destruction; it cannot be left unexamined. Take, then, these five factors as your doctrine, keeping them in your plans as you analyse each situation: first, Morality; second, Heaven; third, Earth; fourth, Generalship; and fifth, Law.

Morality aligns the people with their ruler; it makes them ready to die with him, to live with him, and to fear no danger. Heaven refers to night and day, cold and heat, and seasonal changes. Earth deals with distance and closeness, danger and ease, space and tightness, death and life. Generalship covers wisdom, trustworthiness, benevolence, courage, and discipline. Law refers to order, administration, and logistics.

No general may be ignorant of these five factors. Those who know them will win; those who do not know them will not win. Keep them in your plans as you analyse each situation, asking: which ruler is moral? Which general is more capable? Which side has the advantages of weather and terrain? Which side is better ordered? Which army is stronger? Which side has better trained officers and men? Which side is more transparent in dealing out rewards and punishments? From these things I can predict either victory or defeat.

The general who listens to my strategies will prevail when sent into battle; retain him. The general who does not listen to my strategies will be defeated when sent into battle; dismiss him.

Listen to effective strategies and make the most of any opportunities beyond them. Act for advantage when doing this, that you might control the balance of power.

Warfare is the way of deception. So when you are capable, pretend that you are incapable; when you deploy your troops, pretend that you are not deploying them; when you are close by, pretend that you are far away, and when you are far away, pretend that you are close by. When the enemy holds an advantage, lure him away; when his troops are in disorder, capture him; when he is strong and capable, be prepared to meet him; when he is powerful, avoid him; when he is angry, provoke him further; when he looks down on you, increase his arrogance; when he is well rested, tire him; when his forces are cohesive, sow dissent. Attack where he is ill-prepared; strike where he does not expect it. These tactics of military victory must not be divulged beforehand.

Those who plan much in the temple before battle will be victorious, and those who plan little in the temple before battle will not be victorious. Those who plan much will win, and those who plan little will not win — even more so when they do not plan at all! By observing these matters, I can foresee both victory and defeat.

Chapter 2: Doing Battle

Master Sun said:

Generally speaking, military operations require one thousand fast four-horse chariots, one thousand heavy chariots, one hundred thousand suits of armour, and supplies to be transported a thousand miles. Also, expenses at home and abroad — for the entertainment of guests and emissaries, the purchase of glue and paint, and the maintenance of chariots and armour — will cost one thousand pieces of gold a day. Only then may an army of one hundred thousand soldiers be raised.

When using such an army in battle, long-delayed victories will dull your weapons and lower your morale, assaults on walled cities will exhaust your strength, and an army engaged in a long campaign will drain the state’s resources beyond what it can cope with. And once your weapons have been dulled and your morale lowered, your strength exhausted and your resources depleted, other warlords will seize the chance to profit from your weakness, and then even the wisest advisors will not be able to make the outcome good. Thus, though you may hear of military campaigns that, though clumsy, were swift, you will never see a skilfully managed campaign which is also protracted. There has never been an instance when a state has benefited from prolonged warfare.

He who does not fully comprehend the dangers of warfare will also be unable to fully comprehend the advantages that may be obtained in war. Those who are skilled at warfare will not have to raise a second draft or transport their provisions more than twice, for, though their weapons and equipment come from their home country, their food supplies come from the enemy. In this way their armies remain adequately provisioned.

A country can be made poor because its army requires supplies to be transported long distances, for when supplies must be transported long distances the common people will be impoverished. Wherever an army goes, prices will rise; when prices rise the common people’s wealth will be used up, and when their wealth is used up taxes will be harsher. When your strength has been used up and your wealth has been depleted, each household within the state will also have been emptied, and the common people’s income will have been reduced by seventy percent; while the state’s coffers, due to the destruction and loss of broken chariots, worn-out horses, breastplates, helmets, arrows, bows, halberds, shields, protective mantles, oxen, and heavy carts, will have been reduced by sixty percent. The wise general thus takes his food from the enemy. One cartload of the enemy’s provisions is equivalent to twenty cartloads of your own, and one picul of the enemy’s fodder is equivalent to twenty piculs of your own.

To kill the enemy, anger is needful, and to take the enemy’s resources, rewards are necessary. Thus, in a chariot battle, reward the first person to capture ten or more chariots. Then, replacing their banners with yours, use the captured chariots alongside your own. Also, treat captured soldiers well and provide for them; this is called conquering the enemy and becoming stronger.

Value victory in war, not long campaigns. For the general who understands warfare is the arbiter of the fate of the people, and it is he who controls the security or peril of the state.

Chapter 3: Strategic Attacks

Master Sun said:

In military operations, intact countries are best; broken ones are not as good. Intact armies are best; broken ones are not as good. Intact battalions are best; broken ones are not as good. Intact companies are best; broken ones are not as good. Intact squads are best; broken ones are not as good. Because of this, the highest merit does not lie in winning a hundred victories in a hundred battles; rather, the highest merit lies in vanquishing the enemy without fighting.

Thus, the most excellent method of warfare involves countering the enemy’s schemes, the next best involves thwarting his alliances, and the next after that involves engaging his army. The worst thing to do, however, is to attack a walled city.

Attack walled cities only when you have no other choice. It will take at least three months to prepare protective shields, armoured chariots, and other equipment besides; on top of that, it will take another three months to pile up earthen ramps against the walls. If a general is unable to control his temper and sends his men to swarm the walls like ants, a third of his soldiers will be killed, and even then the city will remain unconquered. Such are the disastrous consequences of siege warfare.

So those who are skilled at warfare vanquish enemy troops without fighting, take enemy cities without attacking them, and destroy enemy states without protracted campaigns. Keeping their forces intact, they compete for the world; in this way their troops will not be worn out, and their gains can be complete. Such is the way of strategic attacks.

This is how you should use your troops: with ten times the enemy’s strength, surround him; with five times the enemy’s strength, attack him; with twice the enemy’s strength, divide him; if evenly matched, make sure you can engage him; if fewer in numbers, make sure you can escape him; if completely outmatched, make sure you can evade him. For however resilient a small force is, a larger force will always capture it.

The general is a pillar of the state. If that pillar is whole, the state will be strong, and if that pillar is fractured, the state will be weak. Now there are three ways by which a ruler may bring disaster on his army. First, he may order an advance, not knowing that the army is in no position to advance, or he may order a retreat, not knowing that the army is in no position to retreat. This is called entangling the army. Second, he may attempt to administer the army while being ignorant of military affairs, thus unsettling the minds of both officers and men. Third, he may violate established authority, being unaware of military hierarchy; this causes both officers and men to become agitated. Now when an army is unsettled and agitated, other warlords are certain to create trouble, and thus it is said: an army in chaos leads the enemy to victory.

There are five ways to know if one will be victorious. He who knows when he can fight and when he cannot fight will be victorious; he who understands how to deploy both large and small forces will be victorious; he whose officers and men share a single purpose will be victorious; he who, ready for battle, awaits an unprepared enemy will be victorious; and finally, the capable general who does not have to deal with his ruler’s interference will be victorious. These five considerations are the way to determine victory.

Thus it is said that he who understands both himself and his opponent will not be defeated in a hundred battles; he who understands himself but not his opponent will lose one battle for each battle he wins; and he who understands neither himself nor his opponent is bound to lose every battle.

Chapter 4: Positioning Your Troops

Master Sun said:

In ancient times, those who were skilled at battle first made themselves impossible to conquer before waiting for opportunities to defeat the enemy. It lies in our own hands to become undefeatable, but opportunities for victory come from the enemy. So while those who are skilled at battle can make themselves impossible to conquer, they cannot make the defeat of the enemy inevitable. Thus it is said: although you might know how to win, you cannot force victory.

Those who cannot win should defend; those who can win should attack. If you lack resources, defend; if your resources are abundant, attack. Skilful defenders conceal themselves in the earth’s most secret depths; skilful attackers bring to bear more inventiveness than the heavens. In this way, they keep themselves safe while obtaining total victory.

The highest merit does not lie in foreseeing a victory that anyone else could have foretold; nor does the highest merit lie in being praised by the whole world for your victories in battle. It doesn’t take much strength to lift an autumn hair; it doesn’t take clear eyes to see the sun and moon; it doesn’t take sharp ears to hear the rolling thunder. Instead, those whom the ancients called skilful in battle conquered where it was easy to conquer. Their victories gained them neither fame for their wisdom nor credit for their courage, and they won their battles without making mistakes. Those who make no mistakes have policies which naturally lead to victory, and they prevail over those who are already in positions of defeat. Indeed, those who are skilled at battle position themselves where they cannot be defeated while squandering no opportunity to defeat the enemy. A victorious army makes sure of victory before going into battle; a losing army fights before making sure of victory.

Those who are skilled at warfare preserve morality and uphold discipline. Thus they can be governors of victory and defeat.

This is the method of warfare. First, consider how difficult the campaign will be; second, consider the scale of operations required; third, consider how many troops you will need; fourth, consider how your forces compare against those of the enemy; and fifth, consider your chances of victory. The terrain will help you to assess how difficult the campaign will be; the difficulty of the campaign will help you to establish the scale of operations required; the scale of operations will tell you how many troops you will need; the size of your forces can then be compared against those of the enemy, and that comparison will then allow you to determine your chances of victory. A victorious army is like a ton against an ounce; a losing army is like an ounce against a ton. And the soldiers of a victorious commander are like the bursting forth of a mountain torrent plunging down a thousand feet; such is their form.

Chapter 5: Force

Master Sun said:

Managing a large force is like managing a small one; it is a matter of how you organize your numbers. Controlling a large force is like controlling a small one; it is a matter of formation and signals. The entire army can be made to withstand enemy attacks without being defeated; this is a matter of combining orthodox and unorthodox tactics. And for its power to increase until it becomes like a grindstone hurled against an egg — this is a matter of weak and strong points.

In battle, use orthodox tactics to engage and unorthodox tactics to conquer. Those who are skilled at devising unorthodox tactics are as rich as heaven and earth, as ceaseless as the rivers, setting and rising like the sun and moon, passing and returning like the four seasons. There are no more than five musical tones, but yet it is impossible to hear every combination of these; there are no more than five primary colours, but yet it is impossible to see every combination of these; and there are no more than five flavours, but yet it is impossible to taste every combination of these. In battle all tactics are either unorthodox or orthodox, but yet it is impossible to exhaust every combination of these. Unorthodox and orthodox arise together, circling endlessly like a ring; who indeed can exhaust them?

The strength of torrential waters rolling boulders along — that is force; the keenness of a raptor breaking its prey beneath it — that is timing. Those who are skilled at battle are deadly in force and precise in timing; their force is like a crossbow stretched, their timing like the trigger-pull.

Amid turmoil and disorder, master the chaos and give it no rein; amid confusion and disarray, stay nimble and you cannot be defeated. For chaos may arise from order, cowardice may arise from courage, and weakness may arise from strength. Order and chaos are a matter of organization; courage and cowardice are a matter of force; strength and weakness are a matter of positioning.

So those who are skilled at manipulating the enemy move in such a way that the enemy must follow, offering bait in such a way that the enemy must take it. Lure him with prizes, but await him with troops.

Those who are skilled at battle seek to maximize force, without depending too much on men; thus, selecting the right men, they can exploit force. The fighting men of those who exploit force are like rolling logs and stones. This is how logs and stones are: on flat ground they stay still, on steep ground they move; if square-shaped they stop, if round they roll on. And the force of those who are skilled at battle is like that of round boulders rolling off a thousand-foot cliff. That is force.

Chapter 6: Weakness and Strength

Master Sun said:

Those who arrive at the battleground early and await the enemy there will be well rested; those who arrive at the battleground late and have to rush into battle will be tired out. Thus those who are skilled at battle control others instead of being controlled by others.

By holding out advantages you can make the enemy approach on his own, and by threatening harm you can deter the enemy from approaching. When the enemy is well-rested, you can tire him; when he has fed well, you can starve him; and when he is in a comfortable spot, you can force him to move. Threaten those places he must rush to defend; move swiftly to places where he does not expect you.

Those who travel a thousand miles without trouble travel through deserted places; those who always conquer when they attack attack that which is undefended; and those who always stand firm in defence defend that which cannot be attacked. And so against those who are skilled at attacking the enemy does not know how to defend, and against those who are skilled at defending the enemy does not know how to attack. Subtle to the point where they seem to have no form, mysterious to the point where they seem to make no sound, they can thus become arbiters of the fate of the enemy.

Those who cannot be resisted when they advance charge into empty space; those who cannot be pursued when they retreat travel at unmatchable speed.

And so when I wish to do battle, even if the enemy has high walls and deep trenches, he has no choice but to engage me, for I attack those places he must rescue. And when I do not wish to do battle, even if I merely draw a line on the ground for defence, the enemy has no way to engage me, and is obedient to my will.

If I know how the enemy has positioned his forces while my own go undiscovered, I can keep my forces compact while his disperse; my forces stay united while his scatter into ten parts, and so I can attack with a ratio of ten against one. My forces will be strong while his will be weak, and, since I will be attacking weakness with strength, those I encounter in battle will be overcome easily.

The place where I intend to do battle must not be divulged, for if it cannot be found out the enemy must defend at many places; and, if the enemy must defend at many places, he will be weak when I encounter him in battle. If he defends his front, his rear will be weak; if he defends his rear, his front will be weak; if he defends his left flank, his right will be weak; if he defends his right flank, his left will be weak; if he defends at every place, he will be weak at every place. Weakness comes from trying to defend against others; strength comes from making others defend against you.

And so, if you know the place and date of battle, you can travel a thousand miles and still be battle-ready; and if he does not know the place or date of battle, his left will not be able to rescue his right, his right will not be able to rescue his left, his front will not be able to rescue his rear, his rear will not be able to rescue his front, and to make matters worse his most distant forces might be ten miles away while even his closest reinforcements might be a few miles away!

The way I see it, Yue might have many troops, but why should that advantage them in matters of victory or defeat? I say: victory can be created. For even if the enemy has numbers, he can be prevented from using them.

Plot, then, that you might know his plans and their likelihood of success. Provoke him, that you might learn the reasons behind his movement or stillness. Identify his positions, that you might ascertain the advantages and disadvantages of the terrain. And compare your strength against his, that you might find out where he is strong or weak.

The height of military formation is to be without form, for without form even the deepest spy cannot find you out and even the wise will not be able to plot against you. Though I employ winning formations and tactics in the sight of all, the masses cannot understand them; everyone knows which formations I used to secure victory, but no one understands how I used them to bring victory about. For each victory is unique, and the formations I can deploy are endless.

Warfare is like water. Water avoids high places and hurries downward; so in war, avoid what is strong and attack what is weak. Water’s course is shaped according to the nature of the terrain, and in war victories are shaped according to the circumstances of the enemy. There are no constant situations in war, just as water has no constant shape. And those who can achieve victory by adapting to the enemy’s own changes are said to be like gods.

None of the five elements is dominant all the time; none of the four seasons remains forever. There are short days and long days, and the moon too wanes and waxes.

Chapter 7: Manoeuvring

Master Sun said:

In military operations the general takes his orders from the ruler, assembling the troops and gathering the people, harmonizing them together. But nothing is more difficult than manoeuvring.

The difficulty in manoeuvring lies in turning the circuitous into the direct and the troublesome into the advantageous. Taking the indirect route, enticing the enemy with advantage, setting off after he does yet arriving before him — all these imply knowledge of the strategies of crooked and straight.

One manoeuvres for advantage, but manoeuvring contains danger. If you raise an army before pursuing advantage you may be too late, but if you send a light detachment forward in pursuit of advantage it will have to leave behind its supplies and stores. If your troops bundle up their armour and hurry forward, marching day and night without rest, covering twice the usual distance and travelling a hundred miles in pursuit of some advantage, your three generals will end up captured; the stronger soldiers will be in front, the weaker at the rear, and only a tenth will reach their destination. If you march fifty miles in pursuit of advantage, your lead general will be defeated, and only half your troops will reach their destination. And if you march thirty miles in pursuit of advantage, only two-thirds of your troops will reach their destination. And without supplies and stores, your army will perish; without provisions it will perish, without stockpiles it will perish.

Those who do not know the plans of other warlords cannot enter into alliances with them; those who do not know the conditions of mountain forests, steep paths, and treacherous swamps cannot move troops; and those who do not use local guides cannot gain the advantages of terrain.

Warfare is about using deception to win, moving for advantage, separating and reuniting your forces as you adapt to each situation. Be swift as the wind, yet calm as the forest; be like a fire when you raid and like a mountain when encamped; be inscrutable as the darkness, but move like thunder and lightning. When looting villages, share the spoils with the men; when occupying captured territory, share the gains. Consider these things before you move. He who knows beforehand the strategies of crooked and straight will win; this is the art of manoeuvring.

The Book of Military Organization says: “Words can be hard to hear, so use cymbals and drums; it can be hard to see, so use banners and flags.” Cymbals, drums, banners, and flags serve to unite ears and eyes as one. United as one, the brave will not advance alone, and the cowardly will not retreat alone. This is the art of using large numbers.

When fighting at night use more torches and drums and when fighting by day use more banners and flags, that you might affect the eyes and ears of the enemy. Thus their three divisions can be robbed of spirit, and their generals can be robbed of morale.

Men’s spirits are sharp in the morning, but by noon they flag and at evening they retire. So those who are good at using troops avoid those keen of spirit, attacking instead the sluggish and retiring. This is the way to deal with morale. Use order to tame chaos and calm to deal with clamour; this is the way to manage the spirit. Use troops at hand to deal with those from afar; set the rested against the tired, the well-fed against the hungry. This is how to manage strength. And do not assault orderly banners or attack organized formations; this is how to manage uncertainty.

In military operations, do not advance against high ground; do not oppose those coming down from the peaks; do not pursue those feigning retreat; do not attack elite troops; do not swallow enemy bait; do not intercept those returning home; when surrounding an army, leave an escape route; and do not chase down the desperate. This is how to use your troops.

Chapter 8: Tactical Variation

Master Sun said:

In military operations the general takes his orders from the ruler, assembling the troops and gathering the people.

Do not camp on treacherous ground; make alliances on intersecting ground; do not linger on isolating ground; on encircled ground, you must strategize; and on death ground, you must fight.

Some roads cannot be taken, some armies cannot be attacked, some cities cannot be assaulted, some ground cannot be contested, and some orders cannot be obeyed.

The general who deeply understands how to vary his tactics for advantage can truly manage war, and the general who does not deeply understand how to vary his tactics for advantage cannot leverage terrain even if he knows the lie of the land. Commanders who do not know the art of tactical variation cannot get the most out of their men even if they understand the five advantages.

This is why the considerations of the wise must take into account all advantages and dangers. By taking the advantages into account one can act with confidence, and by taking the dangers into account one can resolve any crises.

Weaken other warlords with danger; wear them down with trouble; cause them to rush in pursuit of advantage.

In military operations, do not rely on the enemy’s not coming, but rely on your ability to meet him; do not depend on the enemy’s not attacking, but depend on your ability to be unassailable.

The general faces five dangers: if he is reckless, he can be killed; if he tries to preserve his life, he can be captured; if he is hot-tempered, he can be provoked; if he is honourable and upright, he can be shamed; if he loves the people, he can be troubled. These five faults in a general lead to calamity in warfare. The annihilation of the army and the death of the general are caused by these five dangers, which cannot be left unexamined.

Chapter 9: Troop Movement

Master Sun said:

When encamping your troops and observing the enemy, cross over the peaks and keep to the valleys; face the sun, occupy the high ground, and do not ascend to battle an enemy above you. This is how to manage your army in the mountains.

After crossing water, get far away from it. When the enemy comes crossing the water, do not encounter him in the midst of the water; it is more advantageous to let half his troops cross before you attack. If you wish to do battle, do not meet the enemy by the waterside. Stay above them, facing the sun; do not face upstream. This is how to manage your army on water.

After crossing marshes, get away quickly and do not linger. If you encounter an army in the marshes, keep to the reeds with your back to the forest. This is how to manage your army in the marshes.

On flat ground, take a position where you can move easily, and keep your right flank and rear on high ground. In this way, even if your van dies, your rear lives. This is how to manage your army on flat ground.

These were the four positions of military advantage by which the Yellow Emperor was able to conquer four rulers.

Generally speaking, armies prefer high ground and detest low ground; they value sunlit positions and avoid the shadows; they nourish themselves and occupy fertile areas. An army without disease is an army that will win.

In hilly areas, occupy the sunny side and keep your right flank and rear there. Such an army is advantaged by the terrain.

When it rains upstream, the river will foam; if you desire to cross, first wait for the water to subside.

Some regions contain treacherous gullies and naturally-occurring wells, prisons, nets, traps, and crevasses; get away from all these quickly and do not go close to them. For when I am far from them, the enemy is near to them, and when I am facing them the enemy has his back to them.

Close to your army there may be steep paths, grassy ponds, marshes, dense forests, and thick scrub; these must be carefully scouted, as ambushes or spies may lurk there.

When the enemy is silent and close by, he is relying on difficult terrain; when he tries to goad you into battle from a distance, he wants you to advance; if he encamps on easy terrain, he is baiting you; when there is movement among the trees, he is advancing; if many obstacles are hidden in the grass, he wants to make you suspicious; if birds take off suddenly, there are ambushes waiting; and if animals are startled, the main force of the enemy is at hand. When the dust rises high in columns, chariots are advancing; if it rises low and broad, foot soldiers are advancing; if it scatters in different directions, he is gathering firewood; and if a little dust comes and goes, his army is encamping.

If his words are humble but yet he makes preparations, he is going to advance; if he speaks harshly and threatens to attack, he is going to retreat. When his light chariots come out first and take up position on the flanks, his lines are forming up; if he asks for a truce without any prior indication, he is scheming; when there is much running about and soldiers are falling into rank, the hour has come; and if half his troops advance while the other half retreat, he is trying to lure you. If his troops stand leaning on their weapons, they are hungry; when those assigned to collect water drink first, they are thirsty; if he sees advantage but does not move to take it, he is exhausted; if birds gather, there is no one in the camp; and if there are cries at night, his troops are fearful.

If the army is disorderly, the general’s command is weak; if his banners keep moving around, his forces are in disarray; if his officers are angry, they are tired; if his troops kill their horses and eat them, they have run out of provisions; when the cooking pots are no longer hung where they ought to be, he is desperate; and if his troops gather in small groups and murmur among themselves, the general has lost their support.

If he gives rewards too frequently, he is out of resources; if he gives punishments too frequently, he is facing difficulties. If he is harsh at first but then begins to fear his troops, he truly lacks intelligence; and if he comes to you with praises and gifts, he desires a rest. And if his army comes fiercely to meet you but does not engage even after a long time — and yet it does not withdraw — it must be monitored carefully.

Warfare is not just a matter of numbers. Do not advance based solely on your strength; instead concentrate your forces, weigh up the enemy, and seek to capture him. For indeed he who fails to assess the situation and thus underestimates his enemy will end up being captured himself.

If you punish your troops before gaining their affection, they will become disobedient, and if they are disobedient it will be difficult to employ them. But if, after gaining their affection, you do not enforce punishment, they cannot be employed either. So unite them with doctrine and bring them in line with discipline; this is certain victory.

If you use commands consistently when training your soldiers, they will be obedient; and if you do not use commands consistently when training your soldiers, they will not be obedient. All will mutually benefit from the consistent use of commands.

Chapter 10: Terrain

Master Sun said:

These are the types of terrain: accessible ground, entrapping ground, disadvantageous ground, constricted ground, steep ground, and distant ground.

Accessible ground can be entered freely by both myself and my opponent. On such ground, be the first to occupy the high and sunny side, and give priority to your supply lines. This will give you the advantage in battle.

Entrapping ground is easy to enter but difficult to retreat from. On entrapping ground, it is easy to overcome an ill-prepared enemy; however, if the enemy is well-prepared and your assault fails, it will be difficult for you to retreat. This is not advantageous.

Disadvantageous ground is of no use to either myself or the enemy. On disadvantageous ground, even if the enemy lures me with bait, I will not take it; instead I will retreat, and when half of the enemy’s forces have been drawn out I will counterattack. This is advantageous.

If I can be the first to occupy constricted ground, I will fortify it completely and await the enemy there. But if the enemy has occupied it first, I will not attack if he has managed to fortify it completely. If he has not, however, I will attack.

If I can be the first to occupy steep ground, I will await the enemy on the high and sunny side. But if the enemy has occupied it first, I will draw him away and will not attack.

When forces are evenly matched on distant ground, it will be difficult to enter combat, and combat indeed will not be advantageous.

These six are the principles of terrain. They are the highest responsibility of the general, and cannot be left unexamined.

An army may flee, or be insubordinate, or collapse, or fall apart, or be disorganized, or be routed; these six disasters are not brought about by heaven and earth, but by the failures of the general.

All else being equal, when one is set against ten, the result will be flight; if the soldiers are strong but the officers are weak, there will be insubordination; and if the officers are strong but the soldiers are weak, the army will collapse.

If the senior officers are angry and noncompliant to the point where they will encounter the enemy in anger on their own — even before their general has established whether battle is indeed possible — the army will fall apart.

If a general is weak and fails to enforce discipline — if his instructions are unclear, his officers and men inconstant, and his battle-lines messy — that is disorganization.

If a general is unable to properly size up the enemy — so that he assaults large forces with small ones, attacks strength with weakness, and does not have picked soldiers in the van — the result will be rout.

These six are the principles of defeat. They are the highest responsibility of the general, and cannot be left unexamined.

Terrain is an aid to the army. But assessing the enemy, bringing about victory, weighing up dangers and distances — these are the proper concerns of the superior general. He who understands these and uses them in battle will win; he who does not understand these or use them in battle will be defeated. So if the principles of battle indicate victory, you must fight even if the sovereign commands you not to; and if the principles of battle do not indicate victory, no combat is possible even if the sovereign commands it.

He who does not seek fame when advancing, who does not attempt to evade punishment in retreat, who seeks only to defend the people and to benefit his lord — such a one is the treasure of the kingdom.

Look on your soldiers as your infants, and they will follow you through the deepest ravines; look on your soldiers as your beloved sons, and they will die with you. But if you coddle them until they cannot be governed, love them until they cannot be commanded, or let them run rampant until they cannot be managed, they will be like spoilt children, and useless.

If I know that my troops are ready to attack but I do not know that the enemy is in an unassailable position, I only have half a chance of victory; if I know that the enemy is open to attack but I do not know that my own troops are in no position to attack, I only have half a chance of victory; and if I know that the enemy is open to attack and I know that my troops are ready to attack, but I do not know that the terrain makes it impossible to fight, I only have half a chance of victory. But he who knows how to make war moves without becoming confused, taking action without ever running out of options.

So it is said: if I know the enemy and I know myself, I will win and will not be defeated; and if I know the weather and terrain, I can have total victory.

Chapter 11: The Nine Battlegrounds

Master Sun said:

In military operations, we have dispersive ground, trivial ground, contentious ground, open ground, intersecting ground, momentous ground, treacherous ground, encircled ground, and death ground.

Dispersive ground means that a warlord is doing battle on his own territory.

Trivial ground is territory that one has not penetrated deeply.

Contentious ground is territory that can be of advantage to either myself or my opponent.

Open ground is territory where both I and my opponent can move freely.

Intersecting ground refers to places where the territories of three warlords meet, and where the first occupier will be acknowledged as such by the rest of the world.

Momentous ground is territory that one has deeply penetrated, with many walled cities and towns behind him.

Treacherous ground refers to mountain forests, steep paths, marshes, and all country that is hard to traverse.

Encircled ground refers to places arrived at through narrow passes and which can be left only by tortuous paths, and where a small enemy force can gain an advantage over my own larger forces.

Death ground is any place where you must fight desperately in order to survive, and where not fighting will result in your destruction.

Do not fight on dispersive ground; do not halt on trivial ground; do not attack on contentious ground; do not get cut off on open ground; make alliances on intersecting ground; plunder the enemy on momentous ground; on treacherous ground, keep moving; on encircled ground, strategize and scheme; and on death ground, fight.

In ancient times, those who were skilled at warfare could keep the enemy’s front and rear apart, could keep his large and small forces from relying on one another, could keep his nobles and peasants from saving one another, and could keep his upper and lower ranks from working together. Thus when the enemy’s troops were dispersed they could not be assembled, and when his troops were united they could not be set in order.

Move only when there is advantage to be gained. Remain still when there is no such advantage.

You ask: “How should I await an enemy that is great in number, well-organized, and advancing?” I answer: “First seize what he loves, and then he will listen to you.”

Speed is the essence of war. Take advantage of the enemy’s unpreparedness, use routes that he does not have in mind, and attack where he does not expect you.

This is how you should invade: penetrate deeply, that your forces might be concentrated and that defenders might not be able to overcome you; plunder fertile fields, that your army might have enough to eat; nourish your men wisely, and do not tire them out. Focus your breath, and build up your strength. And, when you are moving troops and making schemes, seek to be unfathomable.

Cast your troops where they can find no escape and they will die before fleeing, for in the face of death officers and men will use their utmost strength. Soldiers in desperate straits lose their sense of fear. If there is nowhere to run, they will stand firm; if they are deep within enemy territory, they will keep themselves in check; and if they have no other choice, they will fight. Such troops thus stay alert without needing to be reminded, they give you what you want without your asking for it, they remain loyal without needing to be controlled, and they can be trusted to do their jobs without being ordered to do so. Banish superstition and rumour, and they will face death without a thought.

My troops are not rich, but not because they scorn wealth; they are not long-lived, but not because they scorn long life. When the day comes for them to be sent out those troops sitting down will soak their garments with tears, while those lying down will drench their cheeks. Yet let them be cast where they can find no escape, and they will be as courageous as Zhuan Zhu or Cao Gui.

Those who are skilled at warfare can be compared to the shuairan. The shuairan is a serpent of the Chang Mountains; if you strike at its head, its tail will attack you; if you strike at its tail, its head will attack you; and if you strike at its middle, both head and tail will attack you. You ask: “Can an army be made like the shuairan?” I answer: “It can.” The men of Wu and Yue hate one another, but if they are in the same boat in the midst of a storm they will save one another like left and right hands. It is not enough to count on tying up your horses and burying your chariot wheels. Making your troops one in courage is a matter of organization, and getting the most out of both the strong and the weak is a matter of understanding the battleground. Those who are skilled at warfare lead as if they were leading just one person by the hand. There is no other way.

The general’s task is to be silent and solitary, impartial in governing. He confounds the ears and eyes of his soldiers, so that they might know nothing; he alters his plans and changes his schemes, so that none might see through them; and he varies his encampments and takes circuitous routes, so that none might understand his thoughts. When the right moment comes, the commander is as one who has climbed high and kicked away the ladder; he has penetrated deep into enemy territory and opened fire, he has burned his boats and smashed his cooking pots. Like one driving a flock of sheep he drives his men first one way and then another, none knowing the reason why. For the task of the general is to muster an army and then cast it into peril.

The nine battlegrounds, the advantages of defence and attack, and the principles of human nature — all these cannot be left unexamined.

This is how you should invade: penetrate deeply that your forces might be compact, for if you penetrate shallowly your forces will scatter.

Once an army has left its own country to cross the border into another, it is on isolating ground; if it can be approached on all four sides, it is on intersecting ground; if it has penetrated deeply, it is on momentous ground; if it has penetrated shallowly, it is on trivial ground; if it has enemy strongholds behind it and narrow passes ahead, it is on encircled ground; and if it has no way out, it is on death ground.

On dispersive ground, the general must unite the will of the army; on trivial ground, he must keep his forces together; on contentious ground, he must hurry the troops in the rear; on open ground, he must be vigilant in defence; on intersecting ground, he must strengthen his alliances; on momentous ground, he must ensure that his army is kept supplied; on treacherous ground, he must keep advancing; on encircled ground, he must seal off the openings; and on death ground, he must demonstrate that he does not wish to live. For the nature of the soldier is to resist when he is surrounded, to fight when he has no other choice, and to obey when he is under pressure.

When attacking a large state, the army of a mighty king ensures that enemy forces cannot join together; by overwhelming the enemy, it also ensures that his allies cannot come together. So do not compete to form alliances with the rest of the world, and do not cultivate the rulers of other states. Trust in your own secret counsels and overwhelm the enemy. In this way other cities can be uprooted, and other states can be cast down.

Bestow rewards that do not conform to custom, issue orders not in line with established rules, and command the whole army as if you were instructing just one man. Order your troops to act, but do not tell them why; order them to seize advantage, but do not tell them the dangers; cast them upon doomed ground and they will survive; plunge them onto death ground and they will live. For it is precisely when your troops are in peril that they will be able to bring about victory.

The art of managing an army lies in going along with the enemy’s desires, then concentrating your strength on a single target and killing his general a thousand miles away. This is called accomplishing your objective through cunning and skill.

On the day war is declared, close all your borders, cancel all travel permits, and do not allow any emissaries to pass. Enforce security in the temple and execute your plans. As soon as the enemy presents an opening, you must move in swiftly. Move first against what he loves, conceal your dates and times, and adapt your plans to the circumstances of the enemy in order that you might fight decisively. Begin with the reserve of a maiden, but, once the enemy presents an opening, bring the end with the speed of an escaping hare, so that the enemy will not be able to defend himself in time.

Chapter 12: Attacking with Fire

Master Sun said:

There are five ways to attack with fire. The first is to burn men, the second is to burn provisions, the third is to burn equipment, the fourth is to burn storehouses, and the fifth is to burn supply routes.

To employ fire, one must have the necessary tools. These must be kept ready at all times.

There is a proper time to launch incendiary attacks, and there are proper days on which to start fires. The proper time is when the weather is dry, and the proper days are when the moon is in the constellations of the Winnowing Basket, the Wall, the Wings, or the Chariot. These four stellar mansions mark days of rising wind.

In incendiary attacks, you must use the five types of fire in response to circumstances. When fire breaks out in the enemy camp, respond swiftly from outside it; if the fire is burning but the soldiers are calm, bide your time and do not attack; and when the fire reaches its height, attack if you can and stay put if you cannot.

Fire can also be used outside the camp of the enemy. There is no need to wait till the burning has entered the enemy camp; instead, use fire depending on the circumstances of the moment.

When the fire is upwind, do not attack from downwind. And winds might last long during the day, but they cease at night.

The army must know the five types of fire, and must plan and defend accordingly.

Those who enhance their attacks with fire are wise, and those who enhance their attacks with water are strong. But though water can cut an enemy off, it cannot ravage him.

Woe to those who conquer and are victorious, but do not exploit their gains! For this is but waste and delay. Thus it is said: the enlightened ruler considers things carefully, while the capable general makes the most of them. He does not move without seeking advantage, does not attack unless he can profit by it, and does not do battle unless some danger threatens.

A ruler must not raise an army out of anger, and a general must not do battle out of rage. Move only when there is advantage to be gained, and remain still when there is no such advantage. For anger can revert to happiness and fury return to joy, but a nation once ruined cannot be restored and the dead cannot return to life. So the wise prince is careful, and the good general stays alert; in this way the nation is kept at peace, and the army is kept whole.

Chapter 13: Using Spies

Master Sun said:

Raising an army of a hundred thousand men and marching it a thousand miles will reduce the common people’s income, drain the state’s coffers, and cost one thousand pieces of gold a day. It will cause disruption at home and abroad, exhaust men on the roads, and interfere with the affairs of seven hundred thousand families. Yet armies may face each other for years in pursuit of a single day’s victory. Thus, if you remain ignorant of the enemy’s situation because you are loath to bestow ranks and rewards worth a hundred gold pieces, that is the height of inhumanity, and you will be no general of men, no help to your ruler, and no master of victory.

Wise princes and worthy generals have foreknowledge, that they might conquer when they move and achieve successes beyond the powers of most men. But foreknowledge cannot be acquired from ghosts and spirits, from studying similar situations, or from astrological reckoning. Instead, it must be acquired from men acquainted with the enemy’s situation.

One may employ five kinds of spy: the local agent, the inside agent, the double agent, the doomed spy, and the live spy. When all five are used at once and no one knows how they all fit together, this is called the divine web, the treasure of the sovereign.

Local agents are people from the enemy’s country in our employ; inside agents are enemy officials in our employ; double agents are enemy spies in our employ; doomed spies are given misinformation and sent to the enemy for purposes of deception; and live spies return to us with reports.

No one in the entire military should be kept closer than the spy. No one should be rewarded more greatly, and no matter should be kept more secret than espionage. But without wisdom, spies cannot be used; without morals, spies cannot be managed; and without subtlety, one cannot get the truth from their reports. So be subtle, be subtle! For there is no place where spies cannot be used.

If matters of espionage come to light before they are set in motion, the spy and everyone he told things to must die.

If you wish to attack an army, to besiege a walled city, or to assassinate someone, you must first know the identities of the defending general, his aides-de-camp, and his attached advisors, gate guards, and attendants. Command your spies to inquire into these.

Enemy agents who have come to spy on you must be ferreted out. Then bribe them, instruct them, and house them comfortably, that you might obtain and employ double agents. Through their knowledge, local agents and inside agents can be obtained and employed; through their knowledge, doomed spies can carry misinformation to the enemy; and through their knowledge, live spies can be used as planned. A ruler must know how to employ the five kinds of spy, but the information that makes this possible ultimately comes from double agents. Thus double agents must be rewarded greatly.

In ancient times, the Yin Dynasty came to power because Yi Yin had served the Xia Dynasty, and the Zhou Dynasty came to power because Lu Ya had served the Yin Dynasty. Thus the wise prince and the worthy general use their most intelligent people as spies, and thus they accomplish great things.

Spies are essential to warfare, and the whole army relies on them in order to move.