CHAPTER XIII. THE USE OF SPIES

I. LAYING PLANS

1. Sun Tzŭ said: The art of war is of vital importance to the State.

2. It is a matter of life and death, a road either to safety or to

ruin. Hence it is a subject of inquiry which can on no account be

neglected.

3. The art of war, then, is governed by five constant factors, to be

taken into account in one’s deliberations, when seeking to determine

the conditions obtaining in the field.

4. These are: (1) The Moral Law; (2) Heaven; (3) Earth; (4) The

Commander; (5) Method and discipline.

5, 6. _The Moral Law_ causes the people to be in complete accord with

their ruler, so that they will follow him regardless of their lives,

undismayed by any danger.

7. Heaven signifies night and day, cold and heat, times and seasons.

8. Earth comprises distances, great and small; danger and security;

open ground and narrow passes; the chances of life and death.

9. The Commander stands for the virtues of wisdom, sincerity,

benevolence, courage and strictness.

10. By _Method and discipline_ are to be understood the marshalling of

the army in its proper subdivisions, the gradations of rank among the

officers, the maintenance of roads by which supplies may reach the

army, and the control of military expenditure.

11. These five heads should be familiar to every general: he who knows

them will be victorious; he who knows them not will fail.

12. Therefore, in your deliberations, when seeking to determine the

military conditions, let them be made the basis of a comparison, in

this wise:—

13. (1) Which of the two sovereigns is imbued with the Moral law?

(2) Which of the two generals has most ability?

(3) With whom lie the advantages derived from Heaven and Earth?

(4) On which side is discipline most rigorously enforced?

(5) Which army is the stronger?

(6) On which side are officers and men more highly trained?

(7) In which army is there the greater constancy both in reward and

punishment?

14. By means of these seven considerations I can forecast victory or

defeat.

15. The general that hearkens to my counsel and acts upon it, will

conquer: let such a one be retained in command! The general that

hearkens not to my counsel nor acts upon it, will suffer defeat:—let

such a one be dismissed!

16. While heeding the profit of my counsel, avail yourself also of any

helpful circumstances over and beyond the ordinary rules.

17. According as circumstances are favourable, one should modify one’s

plans.

18. All warfare is based on deception.

19. Hence, when able to attack, we must seem unable; when using our

forces, we must seem inactive; when we are near, we must make the enemy

believe we are far away; when far away, we must make him believe we are

near.

20. Hold out baits to entice the enemy. Feign disorder, and crush him.

21. If he is secure at all points, be prepared for him. If he is in

superior strength, evade him.

22. If your opponent is of choleric temper, seek to irritate him.

Pretend to be weak, that he may grow arrogant.

23. If he is taking his ease, give him no rest. If his forces are

united, separate them.

24. Attack him where he is unprepared, appear where you are not

expected.

25. These military devices, leading to victory, must not be divulged

beforehand.

26. Now the general who wins a battle makes many calculations in his

temple ere the battle is fought. The general who loses a battle makes

but few calculations beforehand. Thus do many calculations lead to

victory, and few calculations to defeat: how much more no calculation

at all! It is by attention to this point that I can foresee who is

likely to win or lose.

II. WAGING WAR

1. Sun Tzŭ said: In the operations of war, where there are in the field

a thousand swift chariots, as many heavy chariots, and a hundred

thousand mail-clad soldiers, with provisions enough to carry them a

thousand _li_, the expenditure at home and at the front, including

entertainment of guests, small items such as glue and paint, and sums

spent on chariots and armour, will reach the total of a thousand ounces

of silver per day. Such is the cost of raising an army of 100,000 men.

2. When you engage in actual fighting, if victory is long in coming,

the men’s weapons will grow dull and their ardour will be damped. If

you lay siege to a town, you will exhaust your strength.

3. Again, if the campaign is protracted, the resources of the State

will not be equal to the strain.

4. Now, when your weapons are dulled, your ardour damped, your strength

exhausted and your treasure spent, other chieftains will spring up to

take advantage of your extremity. Then no man, however wise, will be

able to avert the consequences that must ensue.

5. Thus, though we have heard of stupid haste in war, cleverness has

never been seen associated with long delays.

6. There is no instance of a country having benefited from prolonged

warfare.

7. It is only one who is thoroughly acquainted with the evils of war

that can thoroughly understand the profitable way of carrying it on.

8. The skilful soldier does not raise a second levy, neither are his

supply-waggons loaded more than twice.

9. Bring war material with you from home, but forage on the enemy. Thus

the army will have food enough for its needs.

10. Poverty of the State exchequer causes an army to be maintained by

contributions from a distance. Contributing to maintain an army at a

distance causes the people to be impoverished.

11. On the other hand, the proximity of an army causes prices to go up;

and high prices cause the people’s substance to be drained away.

12. When their substance is drained away, the peasantry will be

afflicted by heavy exactions.

13, 14. With this loss of substance and exhaustion of strength, the

homes of the people will be stripped bare, and three-tenths of their

incomes will be dissipated; while Government expenses for broken

chariots, worn-out horses, breast-plates and helmets, bows and arrows,

spears and shields, protective mantlets, draught-oxen and heavy

waggons, will amount to four-tenths of its total revenue.

15. Hence a wise general makes a point of foraging on the enemy. One

cartload of the enemy’s provisions is equivalent to twenty of one’s

own, and likewise a single picul of his provender is equivalent to

twenty from one’s own store.

16. Now in order to kill the enemy, our men must be roused to anger;

that there may be advantage from defeating the enemy, they must have

their rewards.

17. Therefore in chariot fighting, when ten or more chariots have been

taken, those should be rewarded who took the first. Our own flags

should be substituted for those of the enemy, and the chariots mingled

and used in conjunction with ours. The captured soldiers should be

kindly treated and kept.

18. This is called, using the conquered foe to augment one’s own

strength.

19. In war, then, let your great object be victory, not lengthy

campaigns.

20. Thus it may be known that the leader of armies is the arbiter of

the people’s fate, the man on whom it depends whether the nation shall

be in peace or in peril.

III. ATTACK BY STRATAGEM

1. Sun Tzŭ said: In the practical art of war, the best thing of all is

to take the enemy’s country whole and intact; to shatter and destroy it

is not so good. So, too, it is better to capture an army entire than to

destroy it, to capture a regiment, a detachment or a company entire

than to destroy them.

2. Hence to fight and conquer in all your battles is not supreme

excellence; supreme excellence consists in breaking the enemy’s

resistance without fighting.

3. Thus the highest form of generalship is to baulk the enemy’s plans;

the next best is to prevent the junction of the enemy’s forces; the

next in order is to attack the enemy’s army in the field; and the worst

policy of all is to besiege walled cities.

4. The rule is, not to besiege walled cities if it can possibly be

avoided. The preparation of mantlets, movable shelters, and various

implements of war, will take up three whole months; and the piling up

of mounds over against the walls will take three months more.

5. The general, unable to control his irritation, will launch his men

to the assault like swarming ants, with the result that one-third of

his men are slain, while the town still remains untaken. Such are the

disastrous effects of a siege.

6. Therefore the skilful leader subdues the enemy’s troops without any

fighting; he captures their cities without laying siege to them; he

overthrows their kingdom without lengthy operations in the field.

7. With his forces intact he will dispute the mastery of the Empire,

and thus, without losing a man, his triumph will be complete. This is

the method of attacking by stratagem.

8. It is the rule in war, if our forces are ten to the enemy’s one, to

surround him; if five to one, to attack him; if twice as numerous, to

divide our army into two.

9. If equally matched, we can offer battle; if slightly inferior in

numbers, we can avoid the enemy; if quite unequal in every way, we can

flee from him.

10. Hence, though an obstinate fight may be made by a small force, in

the end it must be captured by the larger force.

11. Now the general is the bulwark of the State: if the bulwark is

complete at all points; the State will be strong; if the bulwark is

defective, the State will be weak.

12. There are three ways in which a ruler can bring misfortune upon his

army:—

13. (1) By commanding the army to advance or to retreat, being ignorant

of the fact that it cannot obey. This is called hobbling the army.

14. (2) By attempting to govern an army in the same way as he

administers a kingdom, being ignorant of the conditions which obtain in

an army. This causes restlessness in the soldier’s minds.

15. (3) By employing the officers of his army without discrimination,

through ignorance of the military principle of adaptation to

circumstances. This shakes the confidence of the soldiers.

16. But when the army is restless and distrustful, trouble is sure to

come from the other feudal princes. This is simply bringing anarchy

into the army, and flinging victory away.

17. Thus we may know that there are five essentials for victory:

(1) He will win who knows when to fight and when not to fight.

(2) He will win who knows how to handle both superior and inferior

forces.

(3) He will win whose army is animated by the same spirit throughout

all its ranks.

(4) He will win who, prepared himself, waits to take the enemy

unprepared.

(5) He will win who has military capacity and is not interfered with by

the sovereign.

Victory lies in the knowledge of these five points.

18. Hence the saying: If you know the enemy and know yourself, you need

not fear the result of a hundred battles. If you know yourself but not

the enemy, for every victory gained you will also suffer a defeat. If

you know neither the enemy nor yourself, you will succumb in every

battle.

IV. TACTICAL DISPOSITIONS

1. Sun Tzŭ said: The good fighters of old first put themselves beyond

the possibility of defeat, and then waited for an opportunity of

defeating the enemy.

2. To secure ourselves against defeat lies in our own hands, but the

opportunity of defeating the enemy is provided by the enemy himself.

3. Thus the good fighter is able to secure himself against defeat, but

cannot make certain of defeating the enemy.

4. Hence the saying: One may _know_ how to conquer without being able

to _do_ it.

5. Security against defeat implies defensive tactics; ability to defeat

the enemy means taking the offensive.

6. Standing on the defensive indicates insufficient strength;

attacking, a superabundance of strength.

7. The general who is skilled in defence hides in the most secret

recesses of the earth; he who is skilled in attack flashes forth from

the topmost heights of heaven. Thus on the one hand we have ability to

protect ourselves; on the other, a victory that is complete.

8. To see victory only when it is within the ken of the common herd is

not the acme of excellence.

9. Neither is it the acme of excellence if you fight and conquer and

the whole Empire says, “Well done!”

10. To lift an autumn hair is no sign of great strength; to see sun and

moon is no sign of sharp sight; to hear the noise of thunder is no sign

of a quick ear.

11. What the ancients called a clever fighter is one who not only wins,

but excels in winning with ease.

12. Hence his victories bring him neither reputation for wisdom nor

credit for courage.

13. He wins his battles by making no mistakes. Making no mistakes is

what establishes the certainty of victory, for it means conquering an

enemy that is already defeated.

14. Hence the skilful fighter puts himself into a position which makes

defeat impossible, and does not miss the moment for defeating the

enemy.

15. Thus it is that in war the victorious strategist only seeks battle

after the victory has been won, whereas he who is destined to defeat

first fights and afterwards looks for victory.

16. The consummate leader cultivates the moral law, and strictly

adheres to method and discipline; thus it is in his power to control

success.

17. In respect of military method, we have, firstly, Measurement;

secondly, Estimation of quantity; thirdly, Calculation; fourthly,

Balancing of chances; fifthly, Victory.

18. Measurement owes its existence to Earth; Estimation of quantity to

Measurement; Calculation to Estimation of quantity; Balancing of

chances to Calculation; and Victory to Balancing of chances.

19. A victorious army opposed to a routed one, is as a pound’s weight

placed in the scale against a single grain.

20. The onrush of a conquering force is like the bursting of pent-up

waters into a chasm a thousand fathoms deep. So much for tactical

dispositions.

V. ENERGY

1. Sun Tzŭ said: The control of a large force is the same principle as

the control of a few men: it is merely a question of dividing up their

numbers.

2. Fighting with a large army under your command is nowise different

from fighting with a small one: it is merely a question of instituting

signs and signals.

3. To ensure that your whole host may withstand the brunt of the

enemy’s attack and remain unshaken—this is effected by manœuvers direct

and indirect.

4. That the impact of your army may be like a grindstone dashed against

an egg—this is effected by the science of weak points and strong.

5. In all fighting, the direct method may be used for joining battle,

but indirect methods will be needed in order to secure victory.

6. Indirect tactics, efficiently applied, are inexhaustible as Heaven

and Earth, unending as the flow of rivers and streams; like the sun and

moon, they end but to begin anew; like the four seasons, they pass away

but to return once more.

7. There are not more than five musical notes, yet the combinations of

these five give rise to more melodies than can ever be heard.

8. There are not more than five primary colours (blue, yellow, red,

white, and black), yet in combination they produce more hues than can

ever be seen.

9. There are not more than five cardinal tastes (sour, acrid, salt,

sweet, bitter), yet combinations of them yield more flavours than can

ever be tasted.

10. In battle, there are not more than two methods of attack—the direct

and the indirect; yet these two in combination give rise to an endless

series of manœuvers.

11. The direct and the indirect lead on to each other in turn. It is

like moving in a circle—you never come to an end. Who can exhaust the

possibilities of their combination?

12. The onset of troops is like the rush of a torrent which will even

roll stones along in its course.

13. The quality of decision is like the well-timed swoop of a falcon

which enables it to strike and destroy its victim.

14. Therefore the good fighter will be terrible in his onset, and

prompt in his decision.

15. Energy may be likened to the bending of a crossbow; decision, to

the releasing of the trigger.

16. Amid the turmoil and tumult of battle, there may be seeming

disorder and yet no real disorder at all; amid confusion and chaos,

your array may be without head or tail, yet it will be proof against

defeat.

17. Simulated disorder postulates perfect discipline; simulated fear

postulates courage; simulated weakness postulates strength.

18. Hiding order beneath the cloak of disorder is simply a question of

subdivision; concealing courage under a show of timidity presupposes a

fund of latent energy; masking strength with weakness is to be effected

by tactical dispositions.

19. Thus one who is skilful at keeping the enemy on the move maintains

deceitful appearances, according to which the enemy will act. He

sacrifices something, that the enemy may snatch at it.

20. By holding out baits, he keeps him on the march; then with a body

of picked men he lies in wait for him.

21. The clever combatant looks to the effect of combined energy, and

does not require too much from individuals. Hence his ability to pick

out the right men and utilise combined energy.

22. When he utilises combined energy, his fighting men become as it

were like unto rolling logs or stones. For it is the nature of a log or

stone to remain motionless on level ground, and to move when on a

slope; if four-cornered, to come to a standstill, but if round-shaped,

to go rolling down.

23. Thus the energy developed by good fighting men is as the momentum

of a round stone rolled down a mountain thousands of feet in height. So

much on the subject of energy.

VI. WEAK POINTS AND STRONG

1. Sun Tzŭ said: Whoever is first in the field and awaits the coming of

the enemy, will be fresh for the fight; whoever is second in the field

and has to hasten to battle, will arrive exhausted.

2. Therefore the clever combatant imposes his will on the enemy, but

does not allow the enemy’s will to be imposed on him.

3. By holding out advantages to him, he can cause the enemy to approach

of his own accord; or, by inflicting damage, he can make it impossible

for the enemy to draw near.

4. If the enemy is taking his ease, he can harass him; if well supplied

with food, he can starve him out; if quietly encamped, he can force him

to move.

5. Appear at points which the enemy must hasten to defend; march

swiftly to places where you are not expected.

6. An army may march great distances without distress, if it marches

through country where the enemy is not.

7. You can be sure of succeeding in your attacks if you only attack

places which are undefended.You can ensure the safety of your defence

if you only hold positions that cannot be attacked.

8. Hence that general is skilful in attack whose opponent does not know

what to defend; and he is skilful in defence whose opponent does not

know what to attack.

9. O divine art of subtlety and secrecy! Through you we learn to be

invisible, through you inaudible; and hence we can hold the enemy’s

fate in our hands.

10. You may advance and be absolutely irresistible, if you make for the

enemy’s weak points; you may retire and be safe from pursuit if your

movements are more rapid than those of the enemy.

11. If we wish to fight, the enemy can be forced to an engagement even

though he be sheltered behind a high rampart and a deep ditch. All we

need do is attack some other place that he will be obliged to relieve.

12. If we do not wish to fight, we can prevent the enemy from engaging

us even though the lines of our encampment be merely traced out on the

ground. All we need do is to throw something odd and unaccountable in

his way.

13. By discovering the enemy’s dispositions and remaining invisible

ourselves, we can keep our forces concentrated, while the enemy’s must

be divided.

14. 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.

15. And if we are able thus to attack an inferior force with a superior

one, our opponents will be in dire straits.

16. 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.

17. 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.

18. Numerical weakness comes from having to prepare against possible

attacks; numerical strength, from compelling our adversary to make

these preparations against us.

19. Knowing the place and the time of the coming battle, we may

concentrate from the greatest distances in order to fight.

20. But if neither time nor place be known, then the left wing will be

impotent to succour the right, the right equally impotent to succour

the left, the van unable to relieve the rear, or the rear to support

the van. How much more so if the furthest portions of the army are

anything under a hundred _li_ apart, and even the nearest are separated

by several _li!_

21. Though according to my estimate the soldiers of Yüeh exceed our own

in number, that shall advantage them nothing in the matter of victory.

I say then that victory can be achieved.

22. 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.

23. Rouse him, and learn the principle of his activity or inactivity.

Force him to reveal himself, so as to find out his vulnerable spots.

24. Carefully compare the opposing army with your own, so that you may

know where strength is superabundant and where it is deficient.

25. 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.

26. How victory may be produced for them out of the enemy’s own

tactics—that is what the multitude cannot comprehend.

27. All men can see the tactics whereby I conquer, but what none can

see is the strategy out of which victory is evolved.

28. Do not repeat the tactics which have gained you one victory, but

let your methods be regulated by the infinite variety of circumstances.

29. Military tactics are like unto water; for water in its natural

course runs away from high places and hastens downwards.

30. So in war, the way is to avoid what is strong and to strike at what

is weak.

31. 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.

32. Therefore, just as water retains no constant shape, so in warfare

there are no constant conditions.

33. He who can modify his tactics in relation to his opponent and

thereby succeed in winning, may be called a heaven-born captain.

34. 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.

VII. MANŒUVERING

1. Sun Tzŭ said: In war, the general receives his commands from the

sovereign.

2. Having collected an army and concentrated his forces, he must blend

and harmonise the different elements thereof before pitching his camp.

3. After that, comes tactical manœuvering, than which there is nothing

more difficult. The difficulty of tactical manœuvering consists in

turning the devious into the direct, and misfortune into gain.

4. 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_.

5. Manœuvering with an army is advantageous; with an undisciplined

multitude, most dangerous.

6. If you set a fully equipped army in 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.

7. Thus, if you order your men to roll up their buff-coats, and make

forced marches without halting day or night, covering double the usual

distance at a stretch, 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.

8. 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.

9. If you march fifty _li_ in order to outmanœuver the enemy, you will

lose the leader of your first division, and only half your force will

reach the goal.

10. If you march thirty _li_ with the same object, two-thirds of your

army will arrive.

11. We may take it then that an army without its baggage-train is lost;

without provisions it is lost; without bases of supply it is lost.

12. We cannot enter into alliances until we are acquainted with the

designs of our neighbours.

13. 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.

14. We shall be unable to turn natural advantages to account unless we

make use of local guides.

15. In war, practise dissimulation, and you will succeed. Move only if

there is a real advantage to be gained.

16. Whether to concentrate or to divide your troops, must be decided by

circumstances.

17. Let your rapidity be that of the wind, your compactness that of the

forest.

18. In raiding and plundering be like fire, in immovability like a

mountain.

19. Let your plans be dark and impenetrable as night, and when you

move, fall like a thunderbolt.

20. When you plunder a countryside, let the spoil be divided amongst

your men; when you capture new territory, cut it up into allotments for

the benefit of the soldiery.

21. Ponder and deliberate before you make a move.

22. He will conquer who has learnt the artifice of deviation. Such is

the art of manœuvering.

23. The 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.

24. Gongs and drums, banners and flags, are means whereby the ears and

eyes of the host may be focussed on one particular point.

25. The host thus forming a single united body, is it impossible either

for the brave to advance alone, or for the cowardly to retreat alone.

This is the art of handling large masses of men.

26. 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.

27. A whole army may be robbed of its spirit; a commander-in-chief may

be robbed of his presence of mind.

28. 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.

29. 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.

30. Disciplined and calm, to await the appearance of disorder and

hubbub amongst the enemy:—this is the art of retaining self-possession.

31. 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.

32. 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.

33. It is a military axiom not to advance uphill against the enemy, nor

to oppose him when he comes downhill.

34. Do not pursue an enemy who simulates flight; do not attack soldiers

whose temper is keen.

35. Do not swallow a bait offered by the enemy. Do not interfere with

an army that is returning home.

36. When you surround an army, leave an outlet free. Do not press a

desperate foe too hard.

37. Such is the art of warfare.

VIII. VARIATION OF TACTICS

1. Sun Tzŭ said: In war, the general receives his commands from the

sovereign, collects his army and concentrates his forces.

2. 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.

3. There are roads which must not be followed, armies which must be not

attacked, towns which must not be besieged, positions which must not be

contested, commands of the sovereign which must not be obeyed.

4. The general who thoroughly understands the advantages that accompany

variation of tactics knows how to handle his troops.

5. 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.

6. So, the student of war who is unversed in the art of war of varying

his plans, even though he be acquainted with the Five Advantages, will

fail to make the best use of his men.

7. Hence in the wise leader’s plans, considerations of advantage and of

disadvantage will be blended together.

8. If our expectation of advantage be tempered in this way, we may

succeed in accomplishing the essential part of our schemes.

9. If, on the other hand, in the midst of difficulties we are always

ready to seize an advantage, we may extricate ourselves from

misfortune.

10. Reduce the hostile chiefs by inflicting damage on them; and make

trouble for them, and keep them constantly engaged; hold out specious

allurements, and make them rush to any given point.

11. 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.

12. There are five dangerous faults which may affect a general:

(1) Recklessness, which leads to destruction;

(2) cowardice, which leads to capture;

(3) a hasty temper, which can be provoked by insults;

(4) a delicacy of honour which is sensitive to shame;

(5) over-solicitude for his men, which exposes him to worry and

trouble.

13. These are the five besetting sins of a general, ruinous to the

conduct of war.

14. 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. THE ARMY ON THE MARCH

1. Sun Tzŭ said: We come now to the question of encamping the army, and

observing signs of the enemy. Pass quickly over mountains, and keep in

the neighbourhood of valleys.

2. Camp in high places, facing the sun. Do not climb heights in order

to fight. So much for mountain warfare.

3. After crossing a river, you should get far away from it.

4. When an invading force crosses a river in its onward march, do not

advance to meet it in mid-stream. It will be best to let half the army

get across, and then deliver your attack.

5. If you are anxious to fight, you should not go to meet the invader

near a river which he has to cross.

6. Moor your craft higher up than the enemy, and facing the sun. Do not

move up-stream to meet the enemy. So much for river warfare.

7. In crossing salt-marshes, your sole concern should be to get over

them quickly, without any delay.

8. If forced to fight in a salt-marsh, you should have water and grass

near you, and get your back to a clump of trees. So much for operations

in salt-marshes.

9. In dry, level country, take up an easily accessible position with

rising ground to your right and on your rear, so that the danger may be

in front, and safety lie behind. So much for campaigning in flat

country.

10. These are the four useful branches of military knowledge which

enabled the Yellow Emperor to vanquish four several sovereigns.

11. All armies prefer high ground to low, and sunny places to dark.

12. If you are careful of your men, and camp on hard ground, the army

will be free from disease of every kind, and this will spell victory.

13. When you come to a hill or a bank, occupy the sunny side, with the

slope on your right rear. Thus you will at once act for the benefit of

your soldiers and utilise the natural advantages of the ground.

14. When, in consequence of heavy rains up-country, a river which you

wish to ford is swollen and flecked with foam, you must wait until it

subsides.

15. Country in which there are precipitous cliffs with torrents running

between, deep natural hollows, confined places, tangled thickets,

quagmires and crevasses, should be left with all possible speed and not

approached.

16. While we keep away from such places, we should get the enemy to

approach them; while we face them, we should let the enemy have them on

his rear.

17. If in the neighbourhood of your camp there should be any hilly

country, ponds surrounded by aquatic grass, hollow basins filled with

reeds, or woods with thick undergrowth, they must be carefully routed

out and searched; for these are places where men in ambush or insidious

spies are likely to be lurking.

18. When the enemy is close at hand and remains quiet, he is relying on

the natural strength of his position.

19. When he keeps aloof and tries to provoke a battle, he is anxious

for the other side to advance.

20. If his place of encampment is easy of access, he is tendering a

bait.

21. Movement amongst the trees of a forest shows that the enemy is

advancing. The appearance of a number of screens in the midst of thick

grass means that the enemy wants to make us suspicious.

22. The rising of birds in their flight is the sign of an ambuscade.

Startled beasts indicate that a sudden attack is coming.

23. When there is dust rising in a high column, it is the sign of

chariots advancing; when the dust is low, but spread over a wide area,

it betokens the approach of infantry. When it branches out in different

directions, it shows that parties have been sent to collect firewood. A

few clouds of dust moving to and fro signify that the army is

encamping.

24. Humble words and increased preparations are signs that the enemy is

about to advance. Violent language and driving forward as if to the

attack are signs that he will retreat.

25. When the light chariots come out first and take up a position on

the wings, it is a sign that the enemy is forming for battle.

26. Peace proposals unaccompanied by a sworn covenant indicate a plot.

27. When there is much running about and the soldiers fall into rank,

it means that the critical moment has come.

28. When some are seen advancing and some retreating, it is a lure.

29. When the soldiers stand leaning on their spears, they are faint

from want of food.

30. If those who are sent to draw water begin by drinking themselves,

the army is suffering from thirst.

31. If the enemy sees an advantage to be gained and makes no effort to

secure it, the soldiers are exhausted.

32. If birds gather on any spot, it is unoccupied. Clamour by night

betokens nervousness.

33. If there is disturbance in the camp, the general’s authority is

weak. If the banners and flags are shifted about, sedition is afoot. If

the officers are angry, it means that the men are weary.

34. When an army feeds its horses with grain and kills its cattle for

food, and when the men do not hang their cooking-pots over the

camp-fires, showing that they will not return to their tents, you may

know that they are determined to fight to the death.

35. The sight of men whispering together in small knots or speaking in

subdued tones points to disaffection amongst the rank and file.

36. Too frequent rewards signify that the enemy is at the end of his

resources; too many punishments betray a condition of dire distress.

37. To begin by bluster, but afterwards to take fright at the enemy’s

numbers, shows a supreme lack of intelligence.

38. When envoys are sent with compliments in their mouths, it is a sign

that the enemy wishes for a truce.

39. If the enemy’s troops march up angrily and remain facing ours for a

long time without either joining battle or taking themselves off again,

the situation is one that demands great vigilance and circumspection.

40. If our troops are no more in number than the enemy, that is amply

sufficient; it only means that no direct attack can be made. What we

can do is simply to concentrate all our available strength, keep a

close watch on the enemy, and obtain reinforcements.

41. He who exercises no forethought but makes light of his opponents is

sure to be captured by them.

42. If soldiers are punished before they have grown attached to you,

they will not prove submissive; and, unless submissive, then will be

practically useless. If, when the soldiers have become attached to you,

punishments are not enforced, they will still be useless.

43. Therefore soldiers must be treated in the first instance with

humanity, but kept under control by means of iron discipline. This is a

certain road to victory.

44. If in training soldiers commands are habitually enforced, the army

will be well-disciplined; if not, its discipline will be bad.

45. If a general shows confidence in his men but always insists on his

orders being obeyed, the gain will be mutual.

X. TERRAIN

1. Sun Tzŭ said: We may distinguish six kinds of terrain, to wit: (1)

Accessible ground; (2) entangling ground; (3) temporising ground; (4)

narrow passes; (5) precipitous heights; (6) positions at a great

distance from the enemy.

2. Ground which can be freely traversed by both sides is called

_accessible_.

3. With regard to ground of this nature, be before the enemy in

occupying the raised and sunny spots, and carefully guard your line of

supplies. Then you will be able to fight with advantage.

4. Ground which can be abandoned but is hard to re-occupy is called

_entangling_.

5. From a position of this sort, if the enemy is unprepared, you may

sally forth and defeat him. But if the enemy is prepared for your

coming, and you fail to defeat him, then, return being impossible,

disaster will ensue.

6. When the position is such that neither side will gain by making the

first move, it is called temporising ground.

7. In a position of this sort, even though the enemy should offer us an

attractive bait, it will be advisable not to stir forth, but rather to

retreat, thus enticing the enemy in his turn; then, when part of his

army has come out, we may deliver our attack with advantage.

8. With regard to _narrow passes_, if you can occupy them first, let

them be strongly garrisoned and await the advent of the enemy.

9. Should the enemy forestall you in occupying a pass, do not go after

him if the pass is fully garrisoned, but only if it is weakly

garrisoned.

10. With regard to _precipitous heights_, if you are beforehand with

your adversary, you should occupy the raised and sunny spots, and there

wait for him to come up.

11. If the enemy has occupied them before you, do not follow him, but

retreat and try to entice him away.

12. If you are situated at a great distance from the enemy, and the

strength of the two armies is equal, it is not easy to provoke a

battle, and fighting will be to your disadvantage.

13. These six are the principles connected with Earth. The general who

has attained a responsible post must be careful to study them.

14. Now an army is exposed to six several calamities, not arising from

natural causes, but from faults for which the general is responsible.

These are: (1) Flight; (2) insubordination; (3) collapse; (4) ruin; (5)

disorganisation; (6) rout.

15. Other conditions being equal, if one force is hurled against

another ten times its size, the result will be the _flight_ of the

former.

16. When the common soldiers are too strong and their officers too

weak, the result is _insubordination_. When the officers are too strong

and the common soldiers too weak, the result is _collapse_.

17. When the higher officers are angry and insubordinate, and on

meeting the enemy give battle on their own account from a feeling of

resentment, before the commander-in-chief can tell whether or no he is

in a position to fight, the result is _ruin_.

18. When the general is weak and without authority; when his orders are

not clear and distinct; when there are no fixed duties assigned to

officers and men, and the ranks are formed in a slovenly haphazard

manner, the result is utter _disorganisation_.

19. When a general, unable to estimate the enemy’s strength, allows an

inferior force to engage a larger one, or hurls a weak detachment

against a powerful one, and neglects to place picked soldiers in the

front rank, the result must be a _rout_.

20. These are six ways of courting defeat, which must be carefully

noted by the general who has attained a responsible post.

21. The natural formation of the country is the soldier’s best ally;

but a power of estimating the adversary, of controlling the forces of

victory, and of shrewdly calculating difficulties, dangers and

distances, constitutes the test of a great general.

22. He who knows these things, and in fighting puts his knowledge into

practice, will win his battles. He who knows them not, nor practises

them, will surely be defeated.

23. If fighting is sure to result in victory, then you must fight, even

though the ruler forbid it; if fighting will not result in victory,

then you must not fight even at the ruler’s bidding.

24. The general who advances without coveting fame and retreats without

fearing disgrace, whose only thought is to protect his country and do

good service for his sovereign, is the jewel of the kingdom.

25. Regard your soldiers as your children, and they will follow you

into the deepest valleys; look on them as your own beloved sons, and

they will stand by you even unto death.

26. If, however, you are indulgent, but unable to make your authority

felt; kind-hearted, but unable to enforce your commands; and incapable,

moreover, of quelling disorder: then your soldiers must be likened to

spoilt children; they are useless for any practical purpose.

27. If we know that our own men are in a condition to attack, but are

unaware that the enemy is not open to attack, we have gone only halfway

towards victory.

28. If we know that the enemy is open to attack, but are unaware that

our own men are not in a condition to attack, we have gone only halfway

towards victory.

29. If we know that the enemy is open to attack, and also know that our

men are in a condition to attack, but are unaware that the nature of

the ground makes fighting impracticable, we have still gone only

halfway towards victory.

30. Hence the experienced soldier, once in motion, is never bewildered;

once he has broken camp, he is never at a loss.

31. Hence the saying: If you know the enemy and know yourself, your

victory will not stand in doubt; if you know Heaven and know Earth, you

may make your victory complete.

XI. THE NINE SITUATIONS

1. Sun Tzŭ said: The art of war recognises nine varieties of ground:

(1) Dispersive ground; (2) facile ground; (3) contentious ground; (4)

open ground; (5) ground of intersecting highways; (6) serious ground;

(7) difficult ground; (8) hemmed-in ground; (9) desperate ground.

2. When a chieftain is fighting in his own territory, it is dispersive

ground.

3. When he has penetrated into hostile territory, but to no great

distance, it is facile ground.

4. Ground the possession of which imports great advantage to either

side, is contentious ground.

5. Ground on which each side has liberty of movement is open ground.

6. Ground which forms the key to three contiguous states, so that he

who occupies it first has most of the Empire at his command, is ground

of intersecting highways.

7. When an army has penetrated into the heart of a hostile country,

leaving a number of fortified cities in its rear, it is serious ground.

8. Mountain forests, rugged steeps, marshes and fens—all country that

is hard to traverse: this is difficult ground.

9. Ground which is reached through narrow gorges, and from which we can

only retire by tortuous paths, so that a small number of the enemy

would suffice to crush a large body of our men: this is hemmed in

ground.

10. Ground on which we can only be saved from destruction by fighting

without delay, is desperate ground.

11. On dispersive ground, therefore, fight not. On facile ground, halt

not. On contentious ground, attack not.

12. On open ground, do not try to block the enemy’s way. On ground of

intersecting highways, join hands with your allies.

13. On serious ground, gather in plunder. In difficult ground, keep

steadily on the march.

14. On hemmed-in ground, resort to stratagem. On desperate ground,

fight.

15. Those who were called skilful leaders of old knew how to drive a

wedge between the enemy’s front and rear; to prevent co-operation

between his large and small divisions; to hinder the good troops from

rescuing the bad, the officers from rallying their men.

16. When the enemy’s men were scattered, they prevented them from

concentrating; even when their forces were united, they managed to keep

them in disorder.

17. When it was to their advantage, they made a forward move; when

otherwise, they stopped still.

18. If asked how to cope with a great host of the enemy in orderly

array and on the point of marching to the attack, I should say: “Begin

by seizing something which your opponent holds dear; then he will be

amenable to your will.”

19. Rapidity is the essence of war: take advantage of the enemy’s

unreadiness, make your way by unexpected routes, and attack unguarded

spots.

20. The following are the principles to be observed by an invading

force: The further you penetrate into a country, the greater will be

the solidarity of your troops, and thus the defenders will not prevail

against you.

21. Make forays in fertile country in order to supply your army with

food.

22. Carefully study the well-being of your men, and do not overtax

them. Concentrate your energy and hoard your strength. Keep your army

continually on the move, and devise unfathomable plans.

23. Throw your soldiers into positions whence there is no escape, and

they will prefer death to flight. If they will face death, there is

nothing they may not achieve. Officers and men alike will put forth

their uttermost strength.

24. Soldiers when in desperate straits lose the sense of fear. If there

is no place of refuge, they will stand firm. If they are in the heart

of a hostile country, they will show a stubborn front. If there is no

help for it, they will fight hard.

25. Thus, without waiting to be marshalled, the soldiers will be

constantly on the _qui vive;_ without waiting to be asked, they will do

your will; without restrictions, they will be faithful; without giving

orders, they can be trusted.

26. Prohibit the taking of omens, and do away with superstitious

doubts. Then, until death itself comes, no calamity need be feared.

27. If our soldiers are not overburdened with money, it is not because

they have a distaste for riches; if their lives are not unduly long, it

is not because they are disinclined to longevity.

28. On the day they are ordered out to battle, your soldiers may weep,

those sitting up bedewing their garments, and those lying down letting

the tears run down their cheeks. But let them once be brought to bay,

and they will display the courage of a Chu or a Kuei.

29. The skilful tactician may be likened to the _shuai-jan_. Now the

_shuai-jan_ is a snake that is found in the Ch‘ang mountains. Strike at

its head, and you will be attacked by its tail; strike at its tail, and

you will be attacked by its head; strike at its middle, and you will be

attacked by head and tail both.

30. Asked if an army can be made to imitate the _shuai-jan_, I should

answer, Yes. For the men of Wu and the men of Yüeh are enemies; yet if

they are crossing a river in the same boat and are caught by a storm,

they will come to each other’s assistance just as the left hand helps

the right.

31. Hence it is not enough to put one’s trust in the tethering of

horses, and the burying of chariot wheels in the ground.

32. The principle on which to manage an army is to set up one standard

of courage which all must reach.

33. How to make the best of both strong and weak—that is a question

involving the proper use of ground.

34. Thus the skilful general conducts his army just as though he were

leading a single man, willy-nilly, by the hand.

35. It is the business of a general to be quiet and thus ensure

secrecy; upright and just, and thus maintain order.

36. He must be able to mystify his officers and men by false reports

and appearances, and thus keep them in total ignorance.

37. By altering his arrangements and changing his plans, he keeps the

enemy without definite knowledge. By shifting his camp and taking

circuitous routes, he prevents the enemy from anticipating his purpose.

38. At the critical moment, the leader of an army acts like one who has

climbed up a height and then kicks away the ladder behind him. He

carries his men deep into hostile territory before he shows his hand.

39. He burns his boats and breaks his cooking-pots; like a shepherd

driving a flock of sheep, he drives his men this way and that, and none

knows whither he is going.

40. To muster his host and bring it into danger:—this may be termed the

business of the general.

41. The different measures suited to the nine varieties of ground; the

expediency of aggressive or defensive tactics; and the fundamental laws

of human nature: these are things that must most certainly be studied.

42. When invading hostile territory, the general principle is, that

penetrating deeply brings cohesion; penetrating but a short way means

dispersion.

43. When you leave your own country behind, and take your army across

neighbourhood territory, you find yourself on critical ground. When

there are means of communication on all four sides, the ground is one

of intersecting highways.

44. When you penetrate deeply into a country, it is serious ground.

When you penetrate but a little way, it is facile ground.

45. When you have the enemy’s strongholds on your rear, and narrow

passes in front, it is hemmed-in ground. When there is no place of

refuge at all, it is desperate ground.

46. Therefore, on dispersive ground, I would inspire my men with unity

of purpose. On facile ground, I would see that there is close

connection between all parts of my army.

47. On contentious ground, I would hurry up my rear.

48. On open ground, I would keep a vigilant eye on my defences. On

ground of intersecting highways, I would consolidate my alliances.

49. On serious ground, I would try to ensure a continuous stream of

supplies. On difficult ground, I would keep pushing on along the road.

50. On hemmed-in ground, I would block any way of retreat. On desperate

ground, I would proclaim to my soldiers the hopelessness of saving

their lives.

51. For it is the soldier’s disposition to offer an obstinate

resistance when surrounded, to fight hard when he cannot help himself,

and to obey promptly when he has fallen into danger.

52. We cannot enter into alliance with neighbouring princes until we

are acquainted with their designs. 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.

53. To be ignorant of any one of the following four or five principles

does not befit a warlike prince.

54. When a warlike prince attacks a powerful state, his generalship

shows itself in preventing the concentration of the enemy’s forces. He

overawes his opponents, and their allies are prevented from joining

against him.

55. Hence he does not strive to ally himself with all and sundry, nor

does he foster the power of other states. He carries out his own secret

designs, keeping his antagonists in awe. Thus he is able to capture

their cities and overthrow their kingdoms.

56. Bestow rewards without regard to rule, issue orders without regard

to previous arrangements; and you will be able to handle a whole army

as though you had to do with but a single man.

57. Confront your soldiers with the deed itself; never let them know

your design. When the outlook is bright, bring it before their eyes;

but tell them nothing when the situation is gloomy.

58. Place your army in deadly peril, and it will survive; plunge it

into desperate straits, and it will come off in safety.

59. For it is precisely when a force has fallen into harm’s way that is

capable of striking a blow for victory.

60. Success in warfare is gained by carefully accommodating ourselves

to the enemy’s purpose.

61. By persistently hanging on the enemy’s flank, we shall succeed in

the long run in killing the commander-in-chief.

62. This is called ability to accomplish a thing by sheer cunning.

63. On the day that you take up your command, block the frontier

passes, destroy the official tallies, and stop the passage of all

emissaries.

64. Be stern in the council-chamber, so that you may control the

situation.

65. If the enemy leaves a door open, you must rush in.

66. Forestall your opponent by seizing what he holds dear, and subtly

contrive to time his arrival on the ground.

67. Walk in the path defined by rule, and accommodate yourself to the

enemy until you can fight a decisive battle.

68. At first, then, exhibit the coyness of a maiden, until the enemy

gives you an opening; afterwards emulate the rapidity of a running

hare, and it will be too late for the enemy to oppose you.

XII. THE ATTACK BY FIRE

1. Sun Tzŭ said: There are five ways of attacking with fire. The first

is to burn soldiers in their camp; the second is to burn stores; the

third is to burn baggage-trains; the fourth is to burn arsenals and

magazines; the fifth is to hurl dropping fire amongst the enemy.

2. In order to carry out an attack, we must have means available. The

material for raising fire should always be kept in readiness.

3. There is a proper season for making attacks with fire, and special

days for starting a conflagration.

4. The proper season is when the weather is very dry; the special days

are those when the moon is in the constellations of the Sieve, the

Wall, the Wing or the Cross-bar; for these four are all days of rising

wind.

5. In attacking with fire, one should be prepared to meet five possible

developments:

6. (1) When fire breaks out inside the enemy’s camp, respond at once

with an attack from without.

7. (2) If there is an outbreak of fire, but the enemy’s soldiers remain

quiet, bide your time and do not attack.

8. (3) When the force of the flames has reached its height, follow it

up with an attack, if that is practicable; if not, stay where you are.

9. (4) If it is possible to make an assault with fire from without, do

not wait for it to break out within, but deliver your attack at a

favourable moment.

10. (5) When you start a fire, be to windward of it. Do not attack from

the leeward.

11. A wind that rises in the daytime lasts long, but a night breeze

soon falls.

12. In every army, the five developments connected with fire must be

known, the movements of the stars calculated, and a watch kept for the

proper days.

13. Hence those who use fire as an aid to the attack show intelligence;

those who use water as an aid to the attack gain an accession of

strength.

14. By means of water, an enemy may be intercepted, but not robbed of

all his belongings.

15. Unhappy is the fate of one who tries to win his battles and succeed

in his attacks without cultivating the spirit of enterprise; for the

result is waste of time and general stagnation.

16. Hence the saying: The enlightened ruler lays his plans well ahead;

the good general cultivates his resources.

17. Move not unless you see an advantage; use not your troops unless

there is something to be gained; fight not unless the position is

critical.

18. No ruler should put troops into the field merely to gratify his own

spleen; no general should fight a battle simply out of pique.

19. If it is to your advantage, make a forward move; if not, stay where

you are.

20. Anger may in time change to gladness; vexation may be succeeded by

content.

21. But a kingdom that has once been destroyed can never come again

into being; nor can the dead ever be brought back to life.

22. Hence the enlightened ruler is heedful, and the good general full

of caution. This is the way to keep a country at peace and an army

intact.

XIII. THE USE OF SPIES

1. Sun Tzŭ said: Raising a host of a hundred thousand men and marching

them great distances entails heavy loss on the people and a drain on

the resources of the State. The daily expenditure will amount to a

thousand ounces of silver. There will be commotion at home and abroad,

and men will drop down exhausted on the highways. As many as seven

hundred thousand families will be impeded in their labor.

2. Hostile armies may face each other for years, striving for the

victory which is decided in a single day. This being so, to remain in

ignorance of the enemy’s condition simply because one grudges the

outlay of a hundred ounces of silver in honours and emoluments, is the

height of inhumanity.

3. One who acts thus is no leader of men, no present help to his

sovereign, no master of victory.

4. Thus, what enables the wise sovereign and the good general to strike

and conquer, and achieve things beyond the reach of ordinary men, is

_foreknowledge_.

5. Now this foreknowledge cannot be elicited from spirits; it cannot be

obtained inductively from experience, nor by any deductive calculation.

6. Knowledge of the enemy’s dispositions can only be obtained from

other men.

7. Hence the use of spies, of whom there are five classes: (1) Local

spies; (2) inward spies; (3) converted spies; (4) doomed spies; (5)

surviving spies.

8. When these five kinds of spy are all at work, none can discover the

secret system. This is called “divine manipulation of the threads.” It

is the sovereign’s most precious faculty.

9. Having _local spies_ means employing the services of the inhabitants

of a district.

10. Having _inward spies_, making use of officials of the enemy.

11. Having _converted spies_, getting hold of the enemy’s spies and

using them for our own purposes.

12. Having _doomed spies_, doing certain things openly for purposes of

deception, and allowing our own spies to know of them and report them

to the enemy.

13. _Surviving spies_, finally, are those who bring back news from the

enemy’s camp.

14. Hence it is that with none in the whole army are more intimate

relations to be maintained than with spies. None should be more

liberally rewarded. In no other business should greater secrecy be

preserved.

15. Spies cannot be usefully employed without a certain intuitive

sagacity.

16. They cannot be properly managed without benevolence and

straightforwardness.

17. Without subtle ingenuity of mind, one cannot make certain of the

truth of their reports.

18. Be subtle! be subtle! and use your spies for every kind of

business.

19. If a secret piece of news is divulged by a spy before the time is

ripe, he must be put to death together with the man to whom the secret

was told.

20. Whether the object be to crush an army, to storm a city, or to

assassinate an individual, it is always necessary to begin by finding

out the names of the attendants, the aides-de-camp, the door-keepers

and sentries of the general in command. Our spies must be commissioned

to ascertain these.

21. The enemy’s spies who have come to spy on us must be sought out,

tempted with bribes, led away and comfortably housed. Thus they will

become converted spies and available for our service.

22. It is through the information brought by the converted spy that we

are able to acquire and employ local and inward spies.

23. It is owing to his information, again, that we can cause the doomed

spy to carry false tidings to the enemy.

24. Lastly, it is by his information that the surviving spy can be used

on appointed occasions.

25. The end and aim of spying in all its five varieties is knowledge of

the enemy; and this knowledge can only be derived, in the first

instance, from the converted spy. Hence it is essential that the

converted spy be treated with the utmost liberality.

26. Of old, the rise of the Yin dynasty was due to I Chih who had

served under the Hsia. Likewise, the rise of the Chou dynasty was due

to Lü Ya who had served under the Yin.

27. Hence it is only the enlightened ruler and the wise general who

will use the highest intelligence of the army for purposes of spying

and thereby they achieve great results. Spies are a most important

element in war, because on them depends an army’s ability to move.

The Art of War(#17405) · 第 13 / 13 章