The Art of War

by Sun Tzu

  By discovering the enemy’s dispositions and remaining invisible ourselves, we can keep our forces concentrated, while the enemy’s must be divided. If the enemy’s dispositions are visible, we can make for him in one body; whereas, our own dispositions being kept secret, the enemy will be obliged to divide his forces in order to guard against attack from every quarter. We can form a single united body, while the enemy must split up into fractions. Hence there will be a whole pitted against separate parts of a whole, which means that we shall be many to the enemy’s few. And if we are able thus to attack an inferior force with a superior one, our opponents will be in dire straits.

  The spot where we intend to fight must not be made known, for then the enemy will have to prepare against a possible attack at several different points; and his forces being thus distributed in many directions, the numbers we shall have to face at any given point will be proportionately few.

  For should the enemy strengthen his van, he will weaken his rear; should he strengthen his rear, he will weaken his van; should he strengthen his left, he will weaken his right; should he strengthen his right, he will weaken his left. If he sends reinforcements everywhere, he will everywhere be weak.

  Numerical weakness comes from having to prepare against possible attacks; numerical strength from compelling our adversary to make these preparations against us. Knowing the place and the time of the coming battle, we may concentrate from the greatest distances in order to fight. But if neither time nor place be known, then the left wing will be impotent to succor the right, the right equally impotent to succor the left, the van unable to relieve the rear, or the rear to support the van. How much more so if the farthest portions of the army are almost a hundred li apart, and even the nearest are separated by several li!

  Though the enemy be stronger in numbers, we may prevent him from fighting. Scheme so as to discover his plans and the likelihood of their success. Rouse him, and learn the principle of his activity or inactivity. Force him to reveal himself, so as to find out his vulnerable spots. Carefully compare the opposing army with your own, so that you may know where strength is superabundant and where it is deficient.

  In making tactical dispositions, the highest pitch you can attain is to conceal them; conceal your dispositions, and you will be safe from the prying of the subtlest spies, from the machinations of the wisest brains.

  What the multitude cannot comprehend is how victory may be produced for them out of the enemy’s own tactics.

  All men can see the individual tactics necessary to conquer, but almost no one can see the strategy out of which total victory is evolved. Military tactics are like unto water; for water in its natural course runs away from high places and hastens downward. So in war, the way is to avoid what is strong and to strike at what is weak. Water shapes its course according to the nature of the ground over which it flows; the soldier works out his victory in relation to the foe whom he is facing.

  Therefore, just as water retains no constant shape, so in warfare there are no constant conditions. The five elements—water, fire, wood, metal, earth—are not always equally predominant; the four seasons make way for each other in turn. There are short days and long; the moon has its periods of waning and waxing. He who can modify his tactics in relation to his opponent, and thereby succeed in winning, may be called a heaven-born captain.

  VII

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  MANEUVERING

  Without harmony in the state, no military expedition can be undertaken; without harmony in the army, no battle array can be formed.

  In war, the general receives his commands from the sovereign. Having collected an army and concentrated his forces, he must blend and harmonize the different elements thereof before pitching his camp.

  After that comes tactical maneuvering, and there is nothing more difficult. The difficulty consists in turning the devious into the direct, and misfortune into gain. Thus, to take a long and circuitous route after enticing the enemy out of the way, and though starting after him to contrive to reach the goal before him, shows knowledge of the artifice of deviation.

  Tu Mu cites the famous march of Chao She in 270 B.C. to relieve the town of O-yu, which was closely invested by a Ch’in army. The King of Chao first consulted Pien P’o on the advisability of attempting a relief, but the latter thought the distance too great, and the intervening country too rugged and difficult. His Majesty then turned to Chao She, who fully admitted the hazardous nature of the march, but finally said: “We shall be like two rats fighting in a hole—and the pluckier one will win!” So he left the capital with his army, but had only gone a distance of thirty li when he stopped and began throwing up entrenchments. For twenty-eight days he continued strengthening his fortifications, and took care that spies should carry the intelligence to the enemy. The Ch’in general was overjoyed, and attributed his adversary’s tardiness to the fact that the beleaguered city was in the Han state, and thus not actually part of Chao territory. But the spies had no sooner departed than Chao She began a forced march lasting for two days and one night, and arrived on the scene of action with such astonishing rapidity that he was able to occupy a commanding position on the “north hill” before the enemy had got wind of his movements. A crushing defeat followed for the Ch’in forces, who were obliged to raise the siege of O-yu in all haste and retreat across the border.

  Maneuvering with an army is advantageous; with an undisciplined multitude, most dangerous. If you set a fully equipped army to march in order to snatch an advantage, the chances are that you will be too late. On the other hand, to detach a flying column for the purpose involves the sacrifice of its baggage and stores.

  Thus, if you order your men to roll up their buffcoats and make forced marches without halting day or night, covering double the usual distance at a stretch, and doing a hundred li in order to wrest an advantage, the leaders of all your three divisions will fall into the hands of the enemy. The stronger men will be in front, the jaded ones will fall behind, and on this plan only one-tenth of your army will reach its destination. If you march fifty li in order to outmaneuver the enemy, you will lose the leader of your first division, and only half your force will reach the goal. If you march thirty li with the same object, two-thirds of your army will arrive. An army without its baggage train is lost; without provisions it is lost; without bases of supply it is lost.

  We cannot enter into alliances until we are acquainted with the designs of our neighbors. We are not fit to lead an army on the march unless we are familiar with the face of the country—its mountains and forests, its pitfalls and precipices, its marshes and swamps. We shall be unable to turn natural advantages to account unless we make use of local guides.

  In war, practice dissimulation and you will succeed. Move only if there is a real advantage to be gained. Whether to concentrate or to divide your troops must be decided by circumstances. Let your rapidity be that of the wind, your compactness that of the forest. In raiding and plundering be like fire, in immovability like a mountain.

  Let your plans be dark and impenetrable as night, and when you move, fall like a thunderbolt. When you plunder a countryside, let the spoil be divided among your men; when you capture new territory, cut it up into allotments for the benefit of the soldiery.

  Ponder and deliberate before you make a move. He will conquer who has learned the artifice of deviation. Such is the art of maneuvering.

  For as the ancient Book of Army Management says: On the field of battle, the spoken word does not carry far enough; hence the institution of gongs and drums. Nor can ordinary objects be seen clearly enough; hence the institution of banners and flags. Gongs and drums, banners and flags, are means whereby the ears and eyes of the host may be focused on one particular point. The host thus forming a single united body, it is impossible either for the brave to advance alone, or for the cowardly to retreat alone.

  Tu Mu tells a story in this connection of Wu Ch’i, when he was fighting against the Ch’in state, approximately 200 B.
C. Before the battle had begun, one of his soldiers, a man of matchless daring, sallied forth by himself, captured two heads from the enemy, and returned to camp. Wu Ch’i had the man instantly executed, whereupon an officer ventured to remonstrate, saying: “This man was a good soldier, and ought not to have been beheaded.” Wu Ch’i replied: “I fully believe he was a good soldier, but I had him beheaded because he acted without orders.”

  This is the art of handling large masses of men.

  In night fighting, then, make much use of signal fires and drums, and in fighting by day, of flags and banners, as a means of influencing the ears and eyes of your army.

  A whole army may be robbed of its spirit; a commander in chief may be robbed of his presence of mind.

  Li Ch’uan tells an anecdote of Ts’ao Kuei, a protégé of Duke Chuang of Lu. The latter state was attacked by Ch’i, and the duke was about to join battle after the first roll of the enemy’s drums, when Ts’ao said: “Not just yet.” Only after their drums had beaten for the third time did he give the word for attack. Then they fought, and the men of Ch’i were utterly defeated. Questioned afterward by the duke as to the meaning of his delay, Ts’ao Kuei replied: “In battle, a courageous spirit is everything. Now the first roll of the drum tends to create this spirit, but with the second it is already on the wane, and after the third it is gone altogether. I attacked when their spirit was gone and ours was at its height. Hence our victory. The value of a whole army—a mighty host of a million men—is dependent on one man alone: such is the influence of spirit!”

  Now a soldier’s spirit is keenest in the morning; by noonday it has begun to flag; and in the evening, his mind is bent only on returning to camp. A clever general, therefore, avoids an army when its spirit is keen, but attacks it when it is sluggish and inclined to return. This is the art of studying moods. Disciplined and calm, he awaits the appearance of disorder and hubbub among the enemy. This is the art of retaining self-possession.

  To be near the goal while the enemy is still far from it, to wait at ease while the enemy is toiling and struggling, to be well fed while the enemy is famished—this is the art of husbanding one’s strength. To refrain from intercepting an enemy whose banners are in perfect order, to refrain from attacking an army drawn up in calm and confident array—this is the art of studying circumstances.

  It is a military axiom not to advance uphill against the enemy, nor to oppose him when he comes downhill. Do not pursue an enemy who simulates flight; do not attack soldiers whose tempers are keen. Do not swallow a bait offered by the enemy.

  Do not interfere with an army that is returning home because a man whose heart is set on returning home will fight to the death against any attempt to bar his way, and is therefore too dangerous an opponent to be tackled.

  When you surround an army, leave an outlet free. This does not mean that the enemy is to be allowed to escape. The object is to make him believe that there is a road to safety, and thus prevent his fighting with the courage of despair.

  For you should not press a desperate foe too hard.

  Ho Shih illustrates with a story taken from the life of Fu Yen-ch’ing. That general was surrounded by a vastly superior army of Khitans in the year A.D. 945. The country was bare and desertlike, and the little Chinese force was soon in dire straits for want of water. The wells they bored ran dry, and the men were reduced to squeezing lumps of mud and sucking out the moisture. Their ranks thinned rapidly, until at last Fu Yen-ch’ing exclaimed: “We are desperate men. Far better to die for our country than to go with fettered hands into captivity!” A strong gale happened to be blowing from the northeast and darkened the air with dense clouds of sandy dust. Tu Chung-wei was for waiting until this had abated before deciding on a final attack; but luckily another officer, Li Shou-cheng by name, was quicker to see an opportunity, and said: “They are many and we are few, but in the midst of this sandstorm our numbers will not be discernible; victory will go to the strenuous fighter, and the wind will be our best ally.” Accordingly, Fu Yen-ch’ing made a sudden and wholly unexpected onslaught with his cavalry, routed the barbarians, and succeeded in breaking through to safety.

  Such is the art of warfare.

  VIII

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  VARIATION OF TACTICS

  When in difficult country, do not encamp. In country where high roads intersect, join hands with your allies. Do not linger in dangerously isolated positions. In hemmed-in situations, you must resort to stratagem. In a desperate position, you must fight.

  There are roads that must not be followed, towns that must not be besieged.

  Almost twenty-two centuries ago, when invading the territory of Hsu-chou, Ts’ao Kung ignored the city of Hua-pi, which lay directly in his path, and pressed on into the heart of the country. This excellent strategy was rewarded by the subsequent capture of no fewer than fourteen important district cities. “No town should be attacked which, if taken, cannot be held, or if left alone, will not cause any trouble.” Hsun Ying, when urged to attack Pi-yang, replied: “The city is small and well fortified; even if I succeed in taking it, it will be no great feat of arms; whereas if I fail, I shall make myself a laughingstock. It is a great mistake to waste men in taking a town when the same expenditure of soldiers will gain a province.”

  There are armies that must not be attacked, positions that must not be contested, commands of the sovereign that must not be obeyed.

  The general who thoroughly understands the advantages that accompany variation of tactics knows how to handle his troops. The general who does not understand these may be well acquainted with the configuration of the country, yet he will not be able to turn his knowledge to practical account.

  In A.D. 404, Liu Yu pursued the rebel Huan Hsuan up the Yangtze and fought a naval battle with him at the island of Ch’eng-hung. The loyal troops numbered only a few thousand, while their opponents were in great force. But Huan Hsuan, fearing the fate that was in store for him should he be overcome, had a light boat made fast to the side of his war junk, so that he might escape, if necessary, at a moment’s notice. The natural result was that the fighting spirit of his soldiers was utterly quenched, and when the loyalists made an attack from windward with fireships, all striving with the utmost ardor to be first in the fray, Huan Hsuan’s forces were routed, had to burn all their baggage, and fled for two days and nights without stopping.

  In the wise leader’s plans, considerations of advantage and of disadvantage will be blended together. If our expectation of advantage be tempered in this way, we may succeed in accomplishing the essential part of our schemes. If, on the other hand, in the midst of difficulties we are always ready to seize an advantage, we may extricate ourselves from misfortune.

  Reduce the hostile chiefs by inflicting damage on them; make trouble for them, and keep them constantly engaged; hold out specious allurements, and make them rush to any given point.

  Chia Lin adds to this section several ways of inflicting this injury: “Entice away the enemy’s best and wisest men, so that he may be left without counselors. Introduce traitors into his country, that the government policy may be rendered futile. Foment intrigue and deceit, and thus sow dissension between the ruler and his ministers. By means of every artful contrivance, cause deterioration among his men and waste of his treasure. Corrupt his morals by insidious gifts leading him into excess. Disturb and unsettle his mind by presenting him with lovely women.”

  The art of war teaches us to rely not on the likelihood of the enemy’s not coming, but on our own readiness to receive him; not on the chance of his not attacking, but rather on the fact that we have made our position unassailable.

  There are five dangerous faults that may affect a general, of which the first two are: recklessness, which leads to destruction; and cowardice, which leads to capture.

  Next there is a delicacy of honor, which is sensitive to shame; and a hasty temper, which can be provoked by insults.

  Yao Hsiang, when opposed in A.D. 357 by Huang
Mei, Teng Ch’iang, and others, shut himself up behind his walls and refused to fight. Teng Ch’iang said: “Our adversary is of a choleric temper and easily provoked; let us make constant sallies and break down his walls, then he will grow angry and come out. Once we can bring his force to battle, it is doomed to be our prey.” This plan was acted upon, Yao Hsiang came out to fight, was lured on as far as San-yuan by the enemy’s pretended flight, and finally attacked and slain.

  The last of such faults is oversolicitude for his men, which exposes him to worry and trouble, for in the long run the troops will suffer more from the defeat, or at best, the prolongation of the war, which will be the consequence.

  These are the five besetting sins of a general, ruinous to the conduct of war. When an army is overthrown and its leader slain, the cause will surely be found among these five dangerous faults. Let them be a subject of meditation.

  IX

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  THE ARMY ON THE MARCH

  He who exercises no forethought but makes light of his opponents is sure to be captured by them. When encamping the army, pass quickly over mountains, and keep in the neighborhood of valleys.

  Wu-tu Ch’iang was a robber captain in the time of the Later Han, approximately 50 A.D., and Ma Yuan was sent to exterminate his gang. Ch’iang having found a refuge in the hills, Ma Yuan made no attempt to force a battle, but seized all the favorable positions commanding supplies of water and forage. Ch’iang was soon in such a desperate plight for want of provisions that he was forced to make a total surrender. He did not know the advantage of keeping in the neighborhood of valleys.