The preparation of mantlets, movable shelters, and various implements of war, will take up three whole months;
[It is not quite clear what the Chinese word, here translated as "mantlets", described. Ts'ao Kung simply defines them as "large shields," but we get a better idea of them from Li Ch'uan, who says they were to protect the heads of those who were assaulting the city walls at close quarters. This seems to suggest a sort of Roman TESTUDO, ready made. Tu Mu says they were wheeled vehicles used in repelling attacks, but this is denied by Ch'en Hao. See supra II. 14. The name is also applied to turrets on city walls. Of the "movable shelters" we get a fairly clear description from several commentators. They were wooden missile-proof structures on four wheels, propelled from within, covered over with raw hides, and used in sieges to convey parties of men to and from the walls, for the purpose of filling up the encircling moat with earth. Tu Mu adds that they are now called "wooden donkeys."]
and the piling up of mounds over against the walls will take three months more.
[These were great mounds or ramparts of earth heaped up to the level of the enemy's walls in order to discover the weak points in the defense, and also to destroy the fortified turrets mentioned in the preceding note.]
5. The general, unable to control his irritation, will launch his men to the assault like swarming ants,
[This vivid simile of Ts'ao Kung is taken from the spectacle of an army of ants climbing a wall. The meaning is that the general, losing patience at the long delay, may make a premature attempt to storm the place before his engines of war are ready.]
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.
[We are reminded of the terrible losses of the Japanese before Port Arthur, in the most recent siege which history has to record.]
6. Therefore the skillful 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.
[Chia Lin notes that he only overthrows the Government, but does no harm to individuals. The classical instance is Wu Wang, who after having put an end to the Yin dynasty was acclaimed "Father and mother of the people."]
7. With his forces intact he will dispute the mastery of the Empire, and thus, without losing a man, his triumph will be complete.
[Owing to the double meanings in the Chinese text, the latter part of the sentence is susceptible of quite a different meaning: "And thus, the weapon not being blunted by use, its keenness remains perfect."]
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;
[Straightway, without waiting for any further advantage.]
if twice as numerous, to divide our army into two.
[Tu Mu takes exception to the saying; and at first sight, indeed, it appears to violate a fundamental principle of war. Ts'ao Kung, however, gives a clue to Sun Tzu's meaning: "Being two to the enemy's one, we may use one part of our army in the regular way, and the other for some special diversion." Chang Yu thus further elucidates the point: "If our force is twice as numerous as that of the enemy, it should be split up into two divisions, one to meet the enemy in front, and one to fall upon his rear; if he replies to the frontal attack, he may be crushed from behind; if to the rearward attack, he may be crushed in front." This is what is meant by saying that 'one part may be used in the regular way, and the other for some special diversion.' Tu Mu does not understand that dividing one's army is simply an irregular, just as concentrating it is the regular, strategical method, and he is too hasty in calling this a mistake."]
9. If equally matched, we can offer battle;
[Li Ch'uan, followed by Ho Shih, gives the following paraphrase: "If attackers and attacked are equally matched in strength, only the able general will fight."]
if slightly inferior in numbers, we can avoid the enemy;
[The meaning, "we can WATCH the enemy," is certainly a great improvement on the above; but unfortunately there appears to be no very good authority for the variant. Chang Yu reminds us that the saying only applies if the other factors are equal; a small difference in numbers is often more than counterbalanced by superior energy and discipline.]
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.
[As Li Ch'uan tersely puts it: "Gap indicates deficiency; if the general's ability is not perfect (i.e. if he is not thoroughly versed in his profession), his army will lack strength."]
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.
[Li Ch'uan adds the comment: "It is like tying together the legs of a thoroughbred, so that it is unable to gallop." One would naturally think of "the ruler" in this passage as being at home, and trying to direct the movements of his army from a distance. But the commentators understand just the reverse, and quote the saying of T'ai Kung: "A kingdom should not be governed from without, and army should not be directed from within." Of course it is true that, during an engagement, or when in close touch with the enemy, the general should not be in the thick of his own troops, but a little distance apart. Otherwise, he will be liable to misjudge the position as a whole, and give wrong orders.]
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.
[Ts'ao Kung's note is, freely translated: "The military sphere and the civil sphere are wholly distinct; you can't handle an army in kid gloves." And Chang Yu says: "Humanity and justice are the principles on which to govern a state, but not an army; opportunism and flexibility, on the other hand, are military rather than civil virtues to assimilate the governing of an army"—to that of a State, understood.]
15. (3) By employing the officers of his army without discrimination,
[That is, he is not careful to use the right man in the right place.]
through ignorance of the military principle of adaptation to circumstances. This shakes the confidence of the soldiers.
[I follow Mei Yao-ch'en here. The other commentators refer not to the ruler, as in SS. 13, 14, but to the officers he employs. Thus Tu Yu says: "If a general is ignorant of the principle of adaptability, he must not be entrusted with a position of authority." Tu Mu quotes: "The skillful employer of men will employ the wise man, the brave man, the covetous man, and the stupid man. For the wise man delights in establishing his merit, the brave man likes to show his courage in action, the covetous man is quick at seizing advantages, and the stupid man has no fear of death."]
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.
[Chang Yu says: If he can fight, he advances and takes the offensive; if he cannot fight, he retreats and remains on the defensive. He will invariably conquer who knows whether it is right to take the offensive or the defensive.]
(2) He will win who knows how to handle both superior and inferior forces.
[This is not merely the general's ability to estimate numbers correctly, as Li Ch'uan and others make out. Chang Yu expounds the saying more satisfactorily: "By applying the art of war, it is possible with a lesser force to defeat a greater, and vice versa. The secret lies in an eye for locality, and in not letting the right moment slip. Thus Wu Tzu says: 'With a superior force, make for easy ground; with an inferior one, make for difficult ground.'"]
(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.
[Tu Yu quotes Wang Tzu as saying: "It is the sovereign's function to give broad instructions, but to decide on battle it is the function of the general." It is needless to dilate on the military disasters which have been caused by undue interference with operations in the field on the part of the home government. Napoleon undoubtedly owed much of his extraordinary success to the fact that he was not hampered by central authority.]
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.
[Li Ch'uan cites the case of Fu Chien, prince of Ch'in, who in 383 A.D. marched with a vast army against the Chin Emperor. When warned not to despise an enemy who could command the services of such men as Hsieh An and Huan Ch'ung, he boastfully replied: "I have the population of eight provinces at my back, infantry and horsemen to the number of one million; why, they could dam up the Yangtsze River itself by merely throwing their whips into the stream. What danger have I to fear?" Nevertheless, his forces were soon after disastrously routed at the Fei River, and he was obliged to beat a hasty retreat.]
If you know neither the enemy nor yourself, you will succumb in every battle.
[Chang Yu said: "Knowing the enemy enables you to take the offensive, knowing yourself enables you to stand on the defensive." He adds: "Attack is the secret of defense; defense is the planning of an attack." It would be hard to find a better epitome of the root-principle of war.]
IV. TACTICAL DISPOSITIONS
[Ts'ao Kung explains the Chinese meaning of the words for the title of this chapter: "marching and countermarching on the part of the two armies with a view to discovering each other's condition." Tu Mu says: "It is through the dispositions of an army that its condition may be discovered. Conceal your dispositions, and your condition will remain secret, which leads to victory,; show your dispositions, and your condition will become patent, which leads to defeat." Wang Hsi remarks that the good general can "secure success by modifying his tactics to meet those of the enemy."]
1. Sun Tzu 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.
[That is, of course, by a mistake on the enemy's part.]
3. Thus the good fighter is able to secure himself against defeat,
[Chang Yu says this is done, "By concealing the disposition of his troops, covering up his tracks, and taking unremitting precautions."]
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.
[I retain the sense found in a similar passage in ss. 1-3, in spite of the fact that the commentators are all against me. The meaning they give, "He who cannot conquer takes the defensive," is plausible enough.]
6. Standing on the defensive indicates insufficient strength; attacking, a superabundance of strength. 7. The general who is skilled in defense hides in the most secret recesses of the earth;
[Literally, "hides under the ninth earth," which is a metaphor indicating the utmost secrecy and concealment, so that the enemy may not know his whereabouts."]
he who is skilled in attack flashes forth from the topmost heights of heaven.
[Another metaphor, implying that he falls on his adversary like a thunderbolt, against which there is no time to prepare. This is the opinion of most of the commentators.]
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.
[As Ts'ao Kung remarks, "the thing is to see the plant before it has germinated," to foresee the event before the action has begun. Li Ch'uan alludes to the story of Han Hsin who, when about to attack the vastly superior army of Chao, which was strongly entrenched in the city of Ch'eng-an, said to his officers: "Gentlemen, we are going to annihilate the enemy, and shall meet again at dinner." The officers hardly took his words seriously, and gave a very dubious assent. But Han Hsin had already worked out in his mind the details of a clever stratagem, whereby, as he foresaw, he was able to capture the city and inflict a crushing defeat on his adversary."]
9. Neither is it the acme of excellence if you fight and conquer and the whole Empire says, "Well done!"
[True excellence being, as Tu Mu says: "To plan secretly, to move surreptitiously, to foil the enemy's intentions and balk his schemes, so that at last the day may be won without shedding a drop of blood." Sun Tzu reserves his approbation for things that "the world's coarse thumb And finger fail to plumb."]
10. To lift an autumn hair is no sign of great strength;
["Autumn" hair" is explained as the fur of a hare, which is finest in autumn, when it begins to grow afresh. The phrase is a very common one in Chinese writers.]
to see the sun and moon is no sign of sharp sight; to hear the noise of thunder is no sign of a quick ear.
[Ho Shih gives as real instances of strength, sharp sight and quick hearing: Wu Huo, who could lift a tripod weighing 250 stone; Li Chu, who at a distance of a hundred paces could see objects no bigger than a mustard seed; and Shih K'uang, a blind musician who could hear the footsteps of a mosquito.]
11. What the ancients called a clever fighter is one who not only wins, but excels in winning with ease.
[The last half is literally "one who, conquering, excels in easy conquering." Mei Yao-ch'en says: "He who only sees the obvious, wins his battles with difficulty; he who looks below the surface of things, wins with ease."]
12. Hence his victories bring him neither reputation for wisdom nor credit for courage.
[Tu Mu explains this very well: "Inasmuch as his victories are gained over circumstances that have not come to light, the world as large knows nothing of them, and he wins no reputation for wisdom; inasmuch as the hostile state submits before there has been any bloodshed, he receives no credit for courage."]
13. He wins his battles by making no mistakes.
[Ch'en Hao says: "He plans no superfluous marches, he devises no futile attacks." The connection of ideas is thus explained by Chang Yu: "One who seeks to conquer by sheer strength, clever though he may be at winning pitched battles, is also liable on occasion to be vanquished; whereas he who can look into the future and discern conditions that are not yet manifest, will never make a blunder and therefore invariably win."]
Making no mistakes is what establishes the certainty of victory, for it means conquering an enemy that is already defeated. 14. Hence the skillful fighter puts himself into a position which makes defeat impossible, and does not miss the moment for defeating the enemy.
[A "counsel of perfection" as Tu Mu truly observes. "Position" need not be confined to the actual ground occupied by the troops. It includes all the arrangements and preparations which a wise general will make to increase the safety of his army.]
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.
[Ho Shih thus expounds the paradox: "In warfare, first lay plans which will ensure victory, and then lead your army to battle; if you will not begin with stratagem but rely on brute strength alone, victory will no longer be assured."]
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.
[It is not easy to distinguish the four terms very clearly in the Chinese. The first seems to be surveying and measurement of the ground, which enable us to form an estimate of the enemy's strength, and to make calculations based on the data thus obtained; we are thus led to a general weighing-up, or comparison of the enemy's chances with our own; if the latter turn the scale, then victory ensues. The chief difficulty lies in third term, which in the Chinese some commentators take as a calculation of NUMBERS, thereby making it nearly synonymous with the second term. Perhaps the second term should be thought of as a consideration of the enemy's general position or condition, while the third term is the estimate of his numerical strength. On the other hand, Tu Mu says: "The question of relative strength having been settled, we can bring the varied resources of cunning into play." Ho Shih seconds this interpretation, but weakens it. However, it points to the third term as being a calculation of numbers.]
19. A victorious army opposed to a routed one, is as a pound's weight placed in the scale against a single grain.
[Literally, "a victorious army is like an I (20 oz.) weighed against a SHU (1/24 oz.); a routed army is a SHU weighed against an I." The point is simply the enormous advantage which a disciplined force, flushed with victory, has over one demoralized by defeat." Legge, in his note on Mencius, I. 2. ix. 2, makes the I to be 24 Chinese ounces, and corrects Chu Hsi's statement that it equaled 20 oz. only. But Li Ch'uan of the T'ang dynasty here gives the same figure as Chu Hsi.]
20. The onrush of a conquering force is like the bursting of pent-up waters into a chasm a thousand fathoms deep.
1. Sun Tzu 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.
[That is, cutting up the army into regiments, companies, etc., with subordinate officers in command of each. Tu Mu reminds us of Han Hsin's famous reply to the first Han Emperor, who once said to him: "How large an army do you think I could lead?" "Not more than 100,000 men, your Majesty." "And you?" asked the Emperor. "Oh!" he answered, "the more the better."]
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 maneuvers direct and indirect.
[We now come to one of the most interesting parts of Sun Tzu's treatise, the discussion of the CHENG and the CH'I." As it is by no means easy to grasp the full significance of these two terms, or to render them consistently by good English equivalents; it may be as well to tabulate some of the commentators' remarks on the subject before proceeding further. Li Ch'uan: "Facing the enemy is CHENG, making lateral diversion is CH'I. Chia Lin: "In presence of the enemy, your troops should be arrayed in normal fashion, but in order to secure victory abnormal maneuvers must be employed." Mei Yao-ch'en: "CH'I is active, CHENG is passive; passivity means waiting for an opportunity, activity beings the victory itself." Ho Shih: "We must cause the enemy to regard our straightforward attack as one that is secretly designed, and vice versa; thus CHENG may also be CH'I, and CH'I may also be CHENG." He instances the famous exploit of Han Hsin, who when marching ostensibly against Lin- chin (now Chao-i in Shensi), suddenly threw a large force across the Yellow River in wooden tubs, utterly disconcerting his opponent. [Ch'ien Han Shu, ch. 3.] Here, we are told, the march on Lin-chin was CHENG, and the surprise maneuver was CH'I." Chang Yu gives the following summary of opinions on the words: "Military writers do not agree with regard to the meaning of CH'I and CHENG. Wei Liao Tzu [4th cent. B.C.] says: 'Direct warfare favors frontal attacks, indirect warfare attacks from the rear.' Ts'ao Kung says: 'Going straight out to join battle is a direct operation; appearing on the enemy's rear is an indirect maneuver.' Li Wei-kung [6th and 7th cent. A.D.] says: 'In war, to march straight ahead is CHENG; turning movements, on the other hand, are CH'I.' These writers simply regard CHENG as CHENG, and CH'I as CH'I; they do not note that the two are mutually interchangeable and run into each other like the two sides of a circle [see infra, ss. 11]. A comment on the T'ang Emperor T'ai Tsung goes to the root of the matter: 'A CH'I maneuver may be CHENG, if we make the enemy look upon it as CHENG; then our real attack will be CH'I, and vice versa. The whole secret lies in confusing the enemy, so that he cannot fathom our real intent.'" To put it perhaps a little more clearly: any attack or other operation is CHENG, on which the enemy has had his attention fixed; whereas that is CH'I," which takes him by surprise or comes from an unexpected quarter. If the enemy perceives a movement which is meant to be CH'I," it immediately becomes CHENG."]
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.
[Chang Yu says: "Steadily develop indirect tactics, either by pounding the enemy's flanks or falling on his rear." A brilliant example of "indirect tactics" which decided the fortunes of a campaign was Lord Roberts' night march round the Peiwar Kotal in the second Afghan war. 
6. Indirect tactics, efficiently applied, are inexhausible as Heaven and Earth, unending as the flow of rivers and streams; like the sun and moon, they end but to begin anew; like the four seasons, they pass away to return once more.
[Tu Yu and Chang Yu understand this of the permutations of CH'I and CHENG." But at present Sun Tzu is not speaking of CHENG at all, unless, indeed, we suppose with Cheng Yu-hsien that a clause relating to it has fallen out of the text. Of course, as has already been pointed out, the two are so inextricably interwoven in all military operations, that they cannot really be considered apart. Here we simply have an expression, in figurative language, of the almost infinite resource of a great leader.]
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 colors (blue, yellow, red, white, and black), yet in combination they produce more hues than can ever been seen. 9 There are not more than five cardinal tastes (sour, acrid, salt, sweet, bitter), yet combinations of them yield more flavors than can ever be tasted. 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 maneuvers. 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.
[The Chinese here is tricky and a certain key word in the context it is used defies the best efforts of the translator. Tu Mu defines this word as "the measurement or estimation of distance." But this meaning does not quite fit the illustrative simile in ss. 15. Applying this definition to the falcon, it seems to me to denote that instinct of SELF RESTRAINT which keeps the bird from swooping on its quarry until the right moment, together with the power of judging when the right moment has arrived. The analogous quality in soldiers is the highly important one of being able to reserve their fire until the very instant at which it will be most effective. When the "Victory" went into action at Trafalgar at hardly more than drifting pace, she was for several minutes exposed to a storm of shot and shell before replying with a single gun. Nelson coolly waited until he was within close range, when the broadside he brought to bear worked fearful havoc on the enemy's nearest ships.]
14. Therefore the good fighter will be terrible in his onset, and prompt in his decision.
[The word "decision" would have reference to the measurement of distance mentioned above, letting the enemy get near before striking. But I cannot help thinking that Sun Tzu meant to use the word in a figurative sense comparable to our own idiom "short and sharp." Cf. Wang Hsi's note, which after describing the falcon's mode of attack, proceeds: "This is just how the 'psychological moment' should be seized in war."]
15. Energy may be likened to the bending of a crossbow; decision, to the releasing of a trigger.
[None of the commentators seem to grasp the real point of the simile of energy and the force stored up in the bent cross- bow until released by the finger on 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.
[Mei Yao-ch'en says: "The subdivisions of the army having been previously fixed, and the various signals agreed upon, the separating and joining, the dispersing and collecting which will take place in the course of a battle, may give the appearance of disorder when no real disorder is possible. Your formation may be without head or tail, your dispositions all topsy-turvy, and yet a rout of your forces quite out of the question."]
17. Simulated disorder postulates perfect discipline, simulated fear postulates courage; simulated weakness postulates strength.
[In order to make the translation intelligible, it is necessary to tone down the sharply paradoxical form of the original. Ts'ao Kung throws out a hint of the meaning in his brief note: "These things all serve to destroy formation and conceal one's condition." But Tu Mu is the first to put it quite plainly: "If you wish to feign confusion in order to lure the enemy on, you must first have perfect discipline; if you wish to display timidity in order to entrap the enemy, you must have extreme courage; if you wish to parade your weakness in order to make the enemy over-confident, you must have exceeding strength."]
18. Hiding order beneath the cloak of disorder is simply a question of subdivision;
[See supra, ss. 1.]
concealing courage under a show of timidity presupposes a fund of latent energy;
[The commentators strongly understand a certain Chinese word here differently than anywhere else in this chapter. Thus Tu Mu says: "seeing that we are favorably circumstanced and yet make no move, the enemy will believe that we are really afraid."]
masking strength with weakness is to be effected by tactical dispositions.
[Chang Yu relates the following anecdote of Kao Tsu, the first Han Emperor: "Wishing to crush the Hsiung-nu, he sent out spies to report on their condition. But the Hsiung-nu, forewarned, carefully concealed all their able-bodied men and well-fed horses, and only allowed infirm soldiers and emaciated cattle to be seen. The result was that spies one and all recommended the Emperor to deliver his attack. Lou Ching alone opposed them, saying: "When two countries go to war, they are naturally inclined to make an ostentatious display of their strength. Yet our spies have seen nothing but old age and infirmity. This is surely some ruse on the part of the enemy, and it would be unwise for us to attack." The Emperor, however, disregarding this advice, fell into the trap and found himself surrounded at Po-teng."]
19. Thus one who is skillful at keeping the enemy on the move maintains deceitful appearances, according to which the enemy will act.
[Ts'ao Kung's note is "Make a display of weakness and want." Tu Mu says: "If our force happens to be superior to the enemy's, weakness may be simulated in order to lure him on; but if inferior, he must be led to believe that we are strong, in order that he may keep off. In fact, all the enemy's movements should be determined by the signs that we choose to give him." Note the following anecdote of Sun Pin, a descendent of Sun Wu: In 341 B.C., the Ch'i State being at war with Wei, sent T'ien Chi and Sun Pin against the general P'ang Chuan, who happened to be a deadly personal enemy of the later. Sun Pin said: "The Ch'i State has a reputation for cowardice, and therefore our adversary despises us. Let us turn this circumstance to account." Accordingly, when the army had crossed the border into Wei territory, he gave orders to show 100,000 fires on the first night, 50,000 on the next, and the night after only 20,000. P'ang Chuan pursued them hotly, saying to himself: "I knew these men of Ch'i were cowards: their numbers have already fallen away by more than half." In his retreat, Sun Pin came to a narrow defile, with he calculated that his pursuers would reach after dark. Here he had a tree stripped of its bark, and inscribed upon it the words: "Under this tree shall P'ang Chuan die." Then, as night began to fall, he placed a strong body of archers in ambush near by, with orders to shoot directly they saw a light. Later on, P'ang Chuan arrived at the spot, and noticing the tree, struck a light in order to read what was written on it. His body was immediately riddled by a volley of arrows, and his whole army thrown into confusion. [The above is Tu Mu's version of the story; the SHIH CHI, less dramatically but probably with more historical truth, makes P'ang Chuan cut his own throat with an exclamation of despair, after the rout of his army.] ]
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.
[With an emendation suggested by Li Ching, this then reads, "He lies in wait with the main body of his troops."]
21. The clever combatant looks to the effect of combined energy, and does not require too much from individuals.
[Tu Mu says: "He first of all considers the power of his army in the bulk; afterwards he takes individual talent into account, and uses each men according to his capabilities. He does not demand perfection from the untalented."]
Hence his ability to pick out the right men and utilize combined energy. 22. When he utilizes combined energy, his fighting men become as it were like unto rolling logs or stones. For it is the nature of a log or stone to remain motionless on level ground, and to move when on a slope; if four-cornered, to come to a standstill, but if round-shaped, to go rolling down.
[Ts'au Kung calls this "the use of natural or inherent power."]
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.
[The chief lesson of this chapter, in Tu Mu's opinion, is the paramount importance in war of rapid evolutions and sudden rushes. "Great results," he adds, "can thus be achieved with small forces."]
 "Forty-one Years in India," chapter 46.
VI. WEAK POINTS AND STRONG
[Chang Yu attempts to explain the sequence of chapters as follows: "Chapter IV, on Tactical Dispositions, treated of the offensive and the defensive; chapter V, on Energy, dealt with direct and indirect methods. The good general acquaints himself first with the theory of attack and defense, and then turns his attention to direct and indirect methods. He studies the art of varying and combining these two methods before proceeding to the subject of weak and strong points. For the use of direct or indirect methods arises out of attack and defense, and the perception of weak and strong points depends again on the above methods. Hence the present chapter comes immediately after the chapter on Energy."]
1. Sun Tzu said: Whoever is first in the field and awaits the coming of the enemy, will be fresh for the fight; whoever is second in the field and has to hasten to battle will arrive exhausted. 2. Therefore the clever combatant imposes his will on the enemy, but does not allow the enemy's will to be imposed on him.
[One mark of a great soldier is that he fight on his own terms or fights not at all.  ]
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.
[In the first case, he will entice him with a bait; in the second, he will strike at some important point which the enemy will have to defend.]
4. If the enemy is taking his ease, he can harass him;
[This passage may be cited as evidence against Mei Yao- Ch'en's interpretation of I. ss. 23.]
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.
[Ts'ao Kung sums up very well: "Emerge from the void [q.d. like "a bolt from the blue"], strike at vulnerable points, shun places that are defended, attack in unexpected quarters."]
7. You can be sure of succeeding in your attacks if you only attack places which are undefended.
[Wang Hsi explains "undefended places" as "weak points; that is to say, where the general is lacking in capacity, or the soldiers in spirit; where the walls are not strong enough, or the precautions not strict enough; where relief comes too late, or provisions are too scanty, or the defenders are variance amongst themselves."]
You can ensure the safety of your defense if you only hold positions that cannot be attacked.
[I.e., where there are none of the weak points mentioned above. There is rather a nice point involved in the interpretation of this later clause. Tu Mu, Ch'en Hao, and Mei Yao-ch'en assume the meaning to be: "In order to make your defense quite safe, you must defend EVEN those places that are not likely to be attacked;" and Tu Mu adds: "How much more, then, those that will be attacked." Taken thus, however, the clause balances less well with the preceding—always a consideration in the highly antithetical style which is natural to the Chinese. Chang Yu, therefore, seems to come nearer the mark in saying: "He who is skilled in attack flashes forth from the topmost heights of heaven [see IV. ss. 7], making it impossible for the enemy to guard against him. This being so, the places that I shall attack are precisely those that the enemy cannot defend.... He who is skilled in defense hides in the most secret recesses of the earth, making it impossible for the enemy to estimate his whereabouts. This being so, the places that I shall hold are precisely those that the enemy cannot attack."]
8. Hence that general is skillful in attack whose opponent does not know what to defend; and he is skillful in defense whose opponent does not know what to attack.
[An aphorism which puts the whole art of war in a nutshell.]
9. O divine art of subtlety and secrecy! Through you we learn to be invisible, through you inaudible;
[Literally, "without form or sound," but it is said of course with reference to the enemy.]
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.
[Tu Mu says: "If the enemy is the invading party, we can cut his line of communications and occupy the roads by which he will have to return; if we are the invaders, we may direct our attack against the sovereign himself." It is clear that Sun Tzu, unlike certain generals in the late Boer war, was no believer in frontal attacks.]
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.
[This extremely concise expression is intelligibly paraphrased by Chia Lin: "even though we have constructed neither wall nor ditch." Li Ch'uan says: "we puzzle him by strange and unusual dispositions;" and Tu Mu finally clinches the meaning by three illustrative anecdotes—one of Chu-ko Liang, who when occupying Yang-p'ing and about to be attacked by Ssu-ma I, suddenly struck his colors, stopped the beating of the drums, and flung open the city gates, showing only a few men engaged in sweeping and sprinkling the ground. This unexpected proceeding had the intended effect; for Ssu-ma I, suspecting an ambush, actually drew off his army and retreated. What Sun Tzu is advocating here, therefore, is nothing more nor less than the timely use of "bluff."]
13. By discovering the enemy's dispositions and remaining invisible ourselves, we can keep our forces concentrated, while the enemy's must be divided.
[The conclusion is perhaps not very obvious, but Chang Yu (after Mei Yao-ch'en) rightly explains it thus: "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."]
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;
[Sheridan once explained the reason of General Grant's victories by saying that "while his opponents were kept fully employed wondering what he was going to do, HE was thinking most of what he was going to do himself."]
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.
[In Frederick the Great's INSTRUCTIONS TO HIS GENERALS we read: "A defensive war is apt to betray us into too frequent detachment. Those generals who have had but little experience attempt to protect every point, while those who are better acquainted with their profession, having only the capital object in view, guard against a decisive blow, and acquiesce in small misfortunes to avoid greater."]
18. Numerical weakness comes from having to prepare against possible attacks; numerical strength, from compelling our adversary to make these preparations against us.
[The highest generalship, in Col. Henderson's words, is "to compel the enemy to disperse his army, and then to concentrate superior force against each fraction in turn."]
19. Knowing the place and the time of the coming battle, we may concentrate from the greatest distances in order to fight.
[What Sun Tzu evidently has in mind is that nice calculation of distances and that masterly employment of strategy which enable a general to divide his army for the purpose of a long and rapid march, and afterwards to effect a junction at precisely the right spot and the right hour in order to confront the enemy in overwhelming strength. Among many such successful junctions which military history records, one of the most dramatic and decisive was the appearance of Blucher just at the critical moment on the field of Waterloo.]
20. 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 furthest portions of the army are anything under a hundred LI apart, and even the nearest are separated by several LI!
[The Chinese of this last sentence is a little lacking in precision, but the mental picture we are required to draw is probably that of an army advancing towards a given rendezvous in separate columns, each of which has orders to be there on a fixed date. If the general allows the various detachments to proceed at haphazard, without precise instructions as to the time and place of meeting, the enemy will be able to annihilate the army in detail. Chang Yu's note may be worth quoting here: "If we do not know the place where our opponents mean to concentrate or the day on which they will join battle, our unity will be forfeited through our preparations for defense, and the positions we hold will be insecure. Suddenly happening upon a powerful foe, we shall be brought to battle in a flurried condition, and no mutual support will be possible between wings, vanguard or rear, especially if there is any great distance between the foremost and hindmost divisions of the army."]
21. Though according to my estimate the soldiers of Yueh exceed our own in number, that shall advantage them nothing in the matter of victory. I say then that victory can be achieved.
[Alas for these brave words! The long feud between the two states ended in 473 B.C. with the total defeat of Wu by Kou Chien and its incorporation in Yueh. This was doubtless long after Sun Tzu's death. With his present assertion compare IV. ss. 4. Chang Yu is the only one to point out the seeming discrepancy, which he thus goes on to explain: "In the chapter on Tactical Dispositions it is said, 'One may KNOW how to conquer without being able to DO it,' whereas here we have the statement that 'victory' can be achieved.' The explanation is, that in the former chapter, where the offensive and defensive are under discussion, it is said that if the enemy is fully prepared, one cannot make certain of beating him. But the present passage refers particularly to the soldiers of Yueh who, according to Sun Tzu's calculations, will be kept in ignorance of the time and place of the impending struggle. That is why he says here 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.
[An alternative reading offered by Chia Lin is: "Know beforehand all plans conducive to our success and to the enemy's failure."
23. Rouse him, and learn the principle of his activity or inactivity.
[Chang Yu tells us that by noting the joy or anger shown by the enemy on being thus disturbed, we shall be able to conclude whether his policy is to lie low or the reverse. He instances the action of Cho-ku Liang, who sent the scornful present of a woman's head-dress to Ssu-ma I, in order to goad him out of his Fabian tactics.]
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.
[Cf. IV. ss. 6.]
25. In making tactical dispositions, the highest pitch you can attain is to conceal them;
[The piquancy of the paradox evaporates in translation. Concealment is perhaps not so much actual invisibility (see supra ss. 9) as "showing no sign" of what you mean to do, of the plans that are formed in your brain.]
conceal your dispositions, and you will be safe from the prying of the subtlest spies, from the machinations of the wisest brains.
[Tu Mu explains: "Though the enemy may have clever and capable officers, they will not be able to lay any plans against us."]
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.
[I.e., everybody can see superficially how a battle is won; what they cannot see is the long series of plans and combinations which has preceded the battle.]
28. Do not repeat the tactics which have gained you one victory, but let your methods be regulated by the infinite variety of circumstances.
[As Wang Hsi sagely remarks: "There is but one root- principle underlying victory, but the tactics which lead up to it are infinite in number." With this compare Col. Henderson: "The rules of strategy are few and simple. They may be learned in a week. They may be taught by familiar illustrations or a dozen diagrams. But such knowledge will no more teach a man to lead an army like Napoleon than a knowledge of grammar will teach him to write like Gibbon."]
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.
[Like water, taking the line of least resistance.]
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;
[That is, as Wang Hsi says: "they predominate alternately."]
the four seasons make way for each other in turn.
[Literally, "have no invariable seat."]
There are short days and long; the moon has its periods of waning and waxing.
[Cf. V. ss. 6. The purport of the passage is simply to illustrate the want of fixity in war by the changes constantly taking place in Nature. The comparison is not very happy, however, because the regularity of the phenomena which Sun Tzu mentions is by no means paralleled in war.]
 See Col. Henderson's biography of Stonewall Jackson, 1902 ed., vol. II, p. 490.
1. Sun Tzu said: In war, the general receives his commands from the sovereign. 2. Having collected an army and concentrated his forces, he must blend and harmonize the different elements thereof before pitching his camp.
["Chang Yu says: "the establishment of harmony and confidence between the higher and lower ranks before venturing into the field;" and he quotes a saying of Wu Tzu (chap. 1 ad init.): "Without harmony in the State, no military expedition can be undertaken; without harmony in the army, no battle array can be formed." In an historical romance Sun Tzu is represented as saying to Wu Yuan: "As a general rule, those who are waging war should get rid of all the domestic troubles before proceeding to attack the external foe."]
3. After that, comes tactical maneuvering, than which there is nothing more difficult.
[I have departed slightly from the traditional interpretation of Ts'ao Kung, who says: "From the time of receiving the sovereign's instructions until our encampment over against the enemy, the tactics to be pursued are most difficult." It seems to me that the tactics or maneuvers can hardly be said to begin until the army has sallied forth and encamped, and Ch'ien Hao's note gives color to this view: "For levying, concentrating, harmonizing and entrenching an army, there are plenty of old rules which will serve. The real difficulty comes when we engage in tactical operations." Tu Yu also observes that "the great difficulty is to be beforehand with the enemy in seizing favorable position."]
The difficulty of tactical maneuvering consists in turning the devious into the direct, and misfortune into gain.
[This sentence contains one of those highly condensed and somewhat enigmatical expressions of which Sun Tzu is so fond. This is how it is explained by Ts'ao Kung: "Make it appear that you are a long way off, then cover the distance rapidly and arrive on the scene before your opponent." Tu Mu says: "Hoodwink the enemy, so that he may be remiss and leisurely while you are dashing along with utmost speed." Ho Shih gives a slightly different turn: "Although you may have difficult ground to traverse and natural obstacles to encounter this is a drawback which can be turned into actual advantage by celerity of movement." Signal examples of this saying are afforded by the two famous passages across the Alps—that of Hannibal, which laid Italy at his mercy, and that of Napoleon two thousand years later, which resulted in the great victory of Marengo.]
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.
[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 Lien 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 whole—and the pluckier one will win!" So he left the capital with his army, but had only gone a distance of 30 LI when he stopped and began throwing up entrenchments. For 28 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 arrive 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.]
5. Maneuvering with an army is advantageous; with an undisciplined multitude, most dangerous.
[I adopt the reading of the T'UNG TIEN, Cheng Yu-hsien and the T'U SHU, since they appear to apply the exact nuance required in order to make sense. The commentators using the standard text take this line to mean that maneuvers may be profitable, or they may be dangerous: it all depends on the ability of the general.]
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.
[Some of the Chinese text is unintelligible to the Chinese commentators, who paraphrase the sentence. I submit my own rendering without much enthusiasm, being convinced that there is some deep-seated corruption in the text. On the whole, it is clear that Sun Tzu does not approve of a lengthy march being undertaken without supplies. Cf. infra, ss. 11.]
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,
[The ordinary day's march, according to Tu Mu, was 30 LI; but on one occasion, when pursuing Liu Pei, Ts'ao Ts'ao is said to have covered the incredible distance of 300 li within twenty-four hours.]
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.
[The moral is, as Ts'ao Kung and others point out: Don't march a hundred LI to gain a tactical advantage, either with or without impedimenta. Maneuvers of this description should be confined to short distances. Stonewall Jackson said: "The hardships of forced marches are often more painful than the dangers of battle." He did not often call upon his troops for extraordinary exertions. It was only when he intended a surprise, or when a rapid retreat was imperative, that he sacrificed everything for speed.  ]
9. 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.
[Literally, "the leader of the first division will be TORN AWAY."]
10. If you march thirty LI with the same object, two-thirds of your army will arrive.
[In the T'UNG TIEN is added: "From this we may know the difficulty of maneuvering."]
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.
[I think Sun Tzu meant "stores accumulated in depots." But Tu Yu says "fodder and the like," Chang Yu says "Goods in general," and Wang Hsi says "fuel, salt, foodstuffs, etc."]
12. We cannot enter into alliances until we are acquainted with the designs of our neighbors. 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 advantage to account unless we make use of local guides.
[ss. 12-14 are repeated in chap. XI. ss. 52.]
15. In war, practice dissimulation, and you will succeed.
[In the tactics of Turenne, deception of the enemy, especially as to the numerical strength of his troops, took a very prominent position.  ]
16. Whether to concentrate or to divide your troops, must be decided by circumstances. 17. Let your rapidity be that of the wind,
[The simile is doubly appropriate, because the wind is not only swift but, as Mei Yao-ch'en points out, "invisible and leaves no tracks."]
your compactness that of the forest.
[Meng Shih comes nearer to the mark in his note: "When slowly marching, order and ranks must be preserved"—so as to guard against surprise attacks. But natural forest do not grow in rows, whereas they do generally possess the quality of density or compactness.]
18. In raiding and plundering be like fire,
[Cf. SHIH CHING, IV. 3. iv. 6: "Fierce as a blazing fire which no man can check."]
in immovability like a mountain.
[That is, when holding a position from which the enemy is trying to dislodge you, or perhaps, as Tu Yu says, when he is trying to entice you into a trap.]
19. Let your plans be dark and impenetrable as night, and when you move, fall like a thunderbolt.
[Tu Yu quotes a saying of T'ai Kung which has passed into a proverb: "You cannot shut your ears to the thunder or your eyes to the lighting—so rapid are they." Likewise, an attack should be made so quickly that it cannot be parried.]
20. When you plunder a countryside, let the spoil be divided amongst your men;
[Sun Tzu wishes to lessen the abuses of indiscriminate plundering by insisting that all booty shall be thrown into a common stock, which may afterwards be fairly divided amongst all.]
when you capture new territory, cut it up into allotments for the benefit of the soldiery.
[Ch'en Hao says "quarter your soldiers on the land, and let them sow and plant it." It is by acting on this principle, and harvesting the lands they invaded, that the Chinese have succeeded in carrying out some of their most memorable and triumphant expeditions, such as that of Pan Ch'ao who penetrated to the Caspian, and in more recent years, those of Fu-k'ang-an and Tso Tsung-t'ang.]
21. Ponder and deliberate before you make a move.
[Chang Yu quotes Wei Liao Tzu as saying that we must not break camp until we have gained the resisting power of the enemy and the cleverness of the opposing general. Cf. the "seven comparisons" in I. ss. 13.]
22. He will conquer who has learnt the artifice of deviation.
[See supra, SS. 3, 4.]
Such is the art of maneuvering.
[With these words, the chapter would naturally come to an end. But there now follows a long appendix in the shape of an extract from an earlier book on War, now lost, but apparently extant at the time when Sun Tzu wrote. The style of this fragment is not noticeable different from that of Sun Tzu himself, but no commentator raises a doubt as to its genuineness.]
23. The Book of Army Management says:
[It is perhaps significant that none of the earlier commentators give us any information about this work. Mei Yao- Ch'en calls it "an ancient military classic," and Wang Hsi, "an old book on war." Considering the enormous amount of fighting that had gone on for centuries before Sun Tzu's time between the various kingdoms and principalities of China, it is not in itself improbable that a collection of military maxims should have been made and written down at some earlier period.]
On the field of battle,
[Implied, though not actually in the Chinese.]
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 focused on one particular point.
[Chang Yu says: "If sight and hearing converge simultaneously on the same object, the evolutions of as many as a million soldiers will be like those of a single man."!]
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.
[Chuang Yu quotes a saying: "Equally guilty are those who advance against orders and those who retreat against orders." Tu Mu tells a story in this connection of Wu Ch'i, when he was fighting against the Ch'in State. 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. 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.
[Ch'en Hao alludes to Li Kuang-pi's night ride to Ho-yang at the head of 500 mounted men; they made such an imposing display with torches, that though the rebel leader Shih Ssu-ming had a large army, he did not dare to dispute their passage.]
27. A whole army may be robbed of its spirit;
["In war," says Chang Yu, "if a spirit of anger can be made to pervade all ranks of an army at one and the same time, its onset will be irresistible. Now the spirit of the enemy's soldiers will be keenest when they have newly arrived on the scene, and it is therefore our cue not to fight at once, but to wait until their ardor and enthusiasm have worn off, and then strike. It is in this way that they may be robbed of their keen spirit." Li Ch'uan and others tell an anecdote (to be found in the TSO CHUAN, year 10, ss. 1) of Ts'ao Kuei, a protege of Duke Chuang of Lu. The latter State was attacked by Ch'i, and the duke was about to join battle at Ch'ang-cho, 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 afterwards 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." Wu Tzu (chap. 4) puts "spirit" first among the "four important influences" in war, and continues: "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!"]
a commander-in-chief may be robbed of his presence of mind.
[Chang Yu says: "Presence of mind is the general's most important asset. It is the quality which enables him to discipline disorder and to inspire courage into the panic- stricken." The great general Li Ching (A.D. 571-649) has a saying: "Attacking does not merely consist in assaulting walled cities or striking at an army in battle array; it must include the art of assailing the enemy's mental equilibrium."]
28. Now a soldier's spirit is keenest in the morning;
[Always provided, I suppose, that he has had breakfast. At the battle of the Trebia, the Romans were foolishly allowed to fight fasting, whereas Hannibal's men had breakfasted at their leisure. See Livy, XXI, liv. 8, lv. 1 and 8.]
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 bait offered by the enemy.
[Li Ch'uan and Tu Mu, with extraordinary inability to see a metaphor, take these words quite literally of food and drink that have been poisoned by the enemy. Ch'en Hao and Chang Yu carefully point out that the saying has a wider application.]
Do not interfere with an army that is returning home.
[The commentators explain this rather singular piece of advice by saying that 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. Chang Yu quotes the words of Han Hsin: "Invincible is the soldier who hath his desire and returneth homewards." A marvelous tale is told of Ts'ao Ts'ao's courage and resource in ch. 1 of the SAN KUO CHI: In 198 A.D., he was besieging Chang Hsiu in Jang, when Liu Piao sent reinforcements with a view to cutting off Ts'ao's retreat. The latter was obliged to draw off his troops, only to find himself hemmed in between two enemies, who were guarding each outlet of a narrow pass in which he had engaged himself. In this desperate plight Ts'ao waited until nightfall, when he bored a tunnel into the mountain side and laid an ambush in it. As soon as the whole army had passed by, the hidden troops fell on his rear, while Ts'ao himself turned and met his pursuers in front, so that they were thrown into confusion and annihilated. Ts'ao Ts'ao said afterwards: "The brigands tried to check my army in its retreat and brought me to battle in a desperate position: hence I knew how to overcome them."]
36. When you surround an army, leave an outlet free.
[This does not mean that the enemy is to be allowed to escape. The object, as Tu Mu puts it, is "to make him believe that there is a road to safety, and thus prevent his fighting with the courage of despair." Tu Mu adds pleasantly: "After that, you may crush him."]
Do not press a desperate foe too hard.
[Ch'en Hao quotes the saying: "Birds and beasts when brought to bay will use their claws and teeth." Chang Yu says: "If your adversary has burned his boats and destroyed his cooking-pots, and is ready to stake all on the issue of a battle, he must not be pushed to extremities." Ho Shih illustrates the meaning by a story taken from the life of Yen-ch'ing. That general, together with his colleague Tu Chung-wei was surrounded by a vastly superior army of Khitans in the year 945 A.D. The country was bare and desert-like, 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 darkening the air with dense clouds of sandy dust. To 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.]
37. Such is the art of warfare.
 See Col. Henderson, op. cit. vol. I. p. 426.
 For a number of maxims on this head, see "Marshal Turenne" (Longmans, 1907), p. 29.
VIII. VARIATION IN TACTICS
[The heading means literally "The Nine Variations," but as Sun Tzu does not appear to enumerate these, and as, indeed, he has already told us (V SS. 6-11) that such deflections from the ordinary course are practically innumerable, we have little option but to follow Wang Hsi, who says that "Nine" stands for an indefinitely large number. "All it means is that in warfare we ought to very our tactics to the utmost degree.... I do not know what Ts'ao Kung makes these Nine Variations out to be, but it has been suggested that they are connected with the Nine Situations" - of chapt. XI. This is the view adopted by Chang Yu. The only other alternative is to suppose that something has been lost—a supposition to which the unusual shortness of the chapter lends some weight.]
1. Sun Tzu said: In war, the general receives his commands from the sovereign, collects his army and concentrates his forces.
[Repeated from VII. ss. 1, where it is certainly more in place. It may have been interpolated here merely in order to supply a beginning to the chapter.]
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.
[The last situation is not one of the Nine Situations as given in the beginning of chap. XI, but occurs later on (ibid. ss. 43. q.v.). Chang Yu defines this situation as being situated across the frontier, in hostile territory. Li Ch'uan says it is "country in which there are no springs or wells, flocks or herds, vegetables or firewood;" Chia Lin, "one of gorges, chasms and precipices, without a road by which to advance."]
In hemmed-in situations, you must resort to stratagem. In desperate position, you must fight. 3. There are roads which must not be followed,
["Especially those leading through narrow defiles," says Li Ch'uan, "where an ambush is to be feared."]
armies which must be not attacked,
[More correctly, perhaps, "there are times when an army must not be attacked." Ch'en Hao says: "When you see your way to obtain a rival advantage, but are powerless to inflict a real defeat, refrain from attacking, for fear of overtaxing your men's strength."]
towns which must not be besieged,
[Cf. III. ss. 4 Ts'ao Kung gives an interesting illustration from his own experience. When invading the territory of Hsu-chou, he 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. Chang Yu says: "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 intaking it, it will be no great feat of arms; whereas if I fail, I shall make myself a laughing-stock." In the seventeenth century, sieges still formed a large proportion of war. It was Turenne who directed attention to the importance of marches, countermarches and maneuvers. He said: "It is a great mistake to waste men in taking a town when the same expenditure of soldiers will gain a province."  ]
positions which must not be contested, commands of the sovereign which must not be obeyed.
[This is a hard saying for the Chinese, with their reverence for authority, and Wei Liao Tzu (quoted by Tu Mu) is moved to exclaim: "Weapons are baleful instruments, strife is antagonistic to virtue, a military commander is the negation of civil order!" The unpalatable fact remains, however, that even Imperial wishes must be subordinated to military necessity.]
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.
[Literally, "get the advantage of the ground," which means not only securing good positions, but availing oneself of natural advantages in every possible way. Chang Yu says: "Every kind of ground is characterized by certain natural features, and also gives scope for a certain variability of plan. How it is possible to turn these natural features to account unless topographical knowledge is supplemented by versatility of mind?"]
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.
[Chia Lin tells us that these imply five obvious and generally advantageous lines of action, namely: "if a certain road is short, it must be followed; if an army is isolated, it must be attacked; if a town is in a parlous condition, it must be besieged; if a position can be stormed, it must be attempted; and if consistent with military operations, the ruler's commands must be obeyed." But there are circumstances which sometimes forbid a general to use these advantages. For instance, "a certain road may be the shortest way for him, but if he knows that it abounds in natural obstacles, or that the enemy has laid an ambush on it, he will not follow that road. A hostile force may be open to attack, but if he knows that it is hard-pressed and likely to fight with desperation, he will refrain from striking," and so on.]
7. Hence in the wise leader's plans, considerations of advantage and of disadvantage will be blended together.
["Whether in an advantageous position or a disadvantageous one," says Ts'ao Kung, "the opposite state should be always present to your mind."]
8. If our expectation of advantage be tempered in this way, we may succeed in accomplishing the essential part of our schemes.
[Tu Mu says: "If we wish to wrest an advantage from the enemy, we must not fix our minds on that alone, but allow for the possibility of the enemy also doing some harm to us, and let this enter as a factor into our calculations."]
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.
[Tu Mu says: "If I wish to extricate myself from a dangerous position, I must consider not only the enemy's ability to injure me, but also my own ability to gain an advantage over the enemy. If in my counsels these two considerations are properly blended, I shall succeed in liberating myself.... For instance; if I am surrounded by the enemy and only think of effecting an escape, the nervelessness of my policy will incite my adversary to pursue and crush me; it would be far better to encourage my men to deliver a bold counter-attack, and use the advantage thus gained to free myself from the enemy's toils." See the story of Ts'ao Ts'ao, VII. ss. 35, note.]
10. Reduce the hostile chiefs by inflicting damage on them;
[Chia Lin enumerates several ways of inflicting this injury, some of which would only occur to the Oriental mind:—"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 amongst 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." Chang Yu (after Wang Hsi) makes a different interpretation of Sun Tzu here: "Get the enemy into a position where he must suffer injury, and he will submit of his own accord."]
and make trouble for them,
[Tu Mu, in this phrase, in his interpretation indicates that trouble should be make for the enemy affecting their "possessions," or, as we might say, "assets," which he considers to be "a large army, a rich exchequer, harmony amongst the soldiers, punctual fulfillment of commands." These give us a whip-hand over the enemy.]
and keep them constantly engaged;
[Literally, "make servants of them." Tu Yu says "prevent the from having any rest."]
hold out specious allurements, and make them rush to any given point.
[Meng Shih's note contains an excellent example of the idiomatic use of: "cause them to forget PIEN (the reasons for acting otherwise than on their first impulse), and hasten in our direction."]
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;
["Bravery without forethought," as Ts'ao Kung analyzes it, which causes a man to fight blindly and desperately like a mad bull. Such an opponent, says Chang Yu, "must not be encountered with brute force, but may be lured into an ambush and slain." Cf. Wu Tzu, chap. IV. ad init.: "In estimating the character of a general, men are wont to pay exclusive attention to his courage, forgetting that courage is only one out of many qualities which a general should possess. The merely brave man is prone to fight recklessly; and he who fights recklessly, without any perception of what is expedient, must be condemned." Ssu-ma Fa, too, make the incisive remark: "Simply going to one's death does not bring about victory."]
(2) cowardice, which leads to capture;
[Ts'ao Kung defines the Chinese word translated here as "cowardice" as being of the man "whom timidity prevents from advancing to seize an advantage," and Wang Hsi adds "who is quick to flee at the sight of danger." Meng Shih gives the closer paraphrase "he who is bent on returning alive," this is, the man who will never take a risk. But, as Sun Tzu knew, nothing is to be achieved in war unless you are willing to take risks. T'ai Kung said: "He who lets an advantage slip will subsequently bring upon himself real disaster." In 404 A.D., Liu Yu pursued the rebel Huan Hsuan up the Yangtsze and fought a naval battle with him at the island of Ch'eng-hung. The loyal troops numbered only a few thousands, while their opponents were in great force. But Huan Hsuan, fearing the fate which was in store for him should be 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. Chang Yu tells a somewhat similar story of Chao Ying-ch'i, a general of the Chin State who during a battle with the army of Ch'u in 597 B.C. had a boat kept in readiness for him on the river, wishing in case of defeat to be the first to get across.]
(3) a hasty temper, which can be provoked by insults;
[Tu Mu tells us that Yao Hsing, when opposed in 357 A.D. 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 as far as San-yuan by the enemy's pretended flight, and finally attacked and slain.]
(4) a delicacy of honor which is sensitive to shame;
[This need not be taken to mean that a sense of honor is really a defect in a general. What Sun Tzu condemns is rather an exaggerated sensitiveness to slanderous reports, the thin-skinned man who is stung by opprobrium, however undeserved. Mei Yao- ch'en truly observes, though somewhat paradoxically: "The seek after glory should be careless of public opinion."]
(5) over-solicitude for his men, which exposes him to worry and trouble.
[Here again, Sun Tzu does not mean that the general is to be careless of the welfare of his troops. All he wishes to emphasize is the danger of sacrificing any important military advantage to the immediate comfort of his men. This is a shortsighted policy, because 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. A mistaken feeling of pity will often induce a general to relieve a beleaguered city, or to reinforce a hard-pressed detachment, contrary to his military instincts. It is now generally admitted that our repeated efforts to relieve Ladysmith in the South African War were so many strategical blunders which defeated their own purpose. And in the end, relief came through the very man who started out with the distinct resolve no longer to subordinate the interests of the whole to sentiment in favor of a part. An old soldier of one of our generals who failed most conspicuously in this war, tried once, I remember, to defend him to me on the ground that he was always "so good to his men." By this plea, had he but known it, he was only condemning him out of Sun Tzu's mouth.]
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.
 "Marshal Turenne," p. 50.
IX. THE ARMY ON THE MARCH
[The contents of this interesting chapter are better indicated in ss. 1 than by this heading.]
1. Sun Tzu 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 neighborhood of valleys.
[The idea is, not to linger among barren uplands, but to keep close to supplies of water and grass. Cf. Wu Tzu, ch. 3: "Abide not in natural ovens," i.e. "the openings of valleys." Chang Yu tells the following anecdote: Wu-tu Ch'iang was a robber captain in the time of the Later Han, 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."]
2. Camp in high places,
[Not on high hills, but on knolls or hillocks elevated above the surrounding country.]
facing the sun.
[Tu Mu takes this to mean "facing south," and Ch'en Hao "facing east." Cf. infra, SS. 11, 13.
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.
["In order to tempt the enemy to cross after you," according to Ts'ao Kung, and also, says Chang Yu, "in order not to be impeded in your evolutions." The T'UNG TIEN reads, "If THE ENEMY crosses a river," etc. But in view of the next sentence, this is almost certainly an interpolation.]
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.
[Li Ch'uan alludes to the great victory won by Han Hsin over Lung Chu at the Wei River. Turning to the CH'IEN HAN SHU, ch. 34, fol. 6 verso, we find the battle described as follows: "The two armies were drawn up on opposite sides of the river. In the night, Han Hsin ordered his men to take some ten thousand sacks filled with sand and construct a dam higher up. Then, leading half his army across, he attacked Lung Chu; but after a time, pretending to have failed in his attempt, he hastily withdrew to the other bank. Lung Chu was much elated by this unlooked-for success, and exclaiming: "I felt sure that Han Hsin was really a coward!" he pursued him and began crossing the river in his turn. Han Hsin now sent a party to cut open the sandbags, thus releasing a great volume of water, which swept down and prevented the greater portion of Lung Chu's army from getting across. He then turned upon the force which had been cut off, and annihilated it, Lung Chu himself being amongst the slain. The rest of the army, on the further bank, also scattered and fled in all directions.]
5. If you are anxious to fight, you should not go to meet the invader near a river which he has to cross.
[For fear of preventing his crossing.]
6. Moor your craft higher up than the enemy, and facing the sun.
[See supra, ss. 2. The repetition of these words in connection with water is very awkward. Chang Yu has the note: "Said either of troops marshaled on the river-bank, or of boats anchored in the stream itself; in either case it is essential to be higher than the enemy and facing the sun." The other commentators are not at all explicit.]
Do not move up-stream to meet the enemy.
[Tu Mu says: "As water flows downwards, we must not pitch our camp on the lower reaches of a river, for fear the enemy should open the sluices and sweep us away in a flood. Chu-ko Wu- hou has remarked that 'in river warfare we must not advance against the stream,' which is as much as to say that our fleet must not be anchored below that of the enemy, for then they would be able to take advantage of the current and make short work of us." There is also the danger, noted by other commentators, that the enemy may throw poison on the water to be carried down to us.]
So much for river warfare. 7. In crossing salt-marshes, your sole concern should be to get over them quickly, without any delay.
[Because of the lack of fresh water, the poor quality of the herbage, and last but not least, because they are low, flat, and exposed to attack.]
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.
[Li Ch'uan remarks that the ground is less likely to be treacherous where there are trees, while Tu Mu says that they will serve to protect the rear.]
So much for operations in salt-marches. 9. In dry, level country, take up an easily accessible position with rising ground to your right and on your rear,
[Tu Mu quotes T'ai Kung as saying: "An army should have a stream or a marsh on its left, and a hill or tumulus on its right."]
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
[Those, namely, concerned with (1) mountains, (2) rivers, (3) marshes, and (4) plains. Compare Napoleon's "Military Maxims," no. 1.]
which enabled the Yellow Emperor to vanquish four several sovereigns.
[Regarding the "Yellow Emperor": Mei Yao-ch'en asks, with some plausibility, whether there is an error in the text as nothing is known of Huang Ti having conquered four other Emperors. The SHIH CHI (ch. 1 ad init.) speaks only of his victories over Yen Ti and Ch'ih Yu. In the LIU T'AO it is mentioned that he "fought seventy battles and pacified the Empire." Ts'ao Kung's explanation is, that the Yellow Emperor was the first to institute the feudal system of vassals princes, each of whom (to the number of four) originally bore the title of Emperor. Li Ch'uan tells us that the art of war originated under Huang Ti, who received it from his Minister Feng Hou.]
11. All armies prefer high ground to low.
["High Ground," says Mei Yao-ch'en, "is not only more agreement and salubrious, but more convenient from a military point of view; low ground is not only damp and unhealthy, but also disadvantageous for fighting."]
and sunny places to dark. 12. If you are careful of your men,
[Ts'ao Kung says: "Make for fresh water and pasture, where you can turn out your animals to graze."]
and camp on hard ground, the army will be free from disease of every kind,
[Chang Yu says: "The dryness of the climate will prevent the outbreak of illness."]
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 utilize 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,
[The latter defined as "places enclosed on every side by steep banks, with pools of water at the bottom.]
[Defined as "natural pens or prisons" or "places surrounded by precipices on three sides—easy to get into, but hard to get out of."]
[Defined as "places covered with such dense undergrowth that spears cannot be used."]
[Defined as "low-lying places, so heavy with mud as to be impassable for chariots and horsemen."]
[Defined by Mei Yao-ch'en as "a narrow difficult way between beetling cliffs." Tu Mu's note is "ground covered with trees and rocks, and intersected by numerous ravines and pitfalls." This is very vague, but Chia Lin explains it clearly enough as a defile or narrow pass, and Chang Yu takes much the same view. On the whole, the weight of the commentators certainly inclines to the rendering "defile." But the ordinary meaning of the Chinese in one place is "a crack or fissure" and the fact that the meaning of the Chinese elsewhere in the sentence indicates something in the nature of a defile, make me think that Sun Tzu is here speaking of 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 neighborhood 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.
[Chang Yu has the note: "We must also be on our guard against traitors who may lie in close covert, secretly spying out our weaknesses and overhearing our instructions."]
18. When the enemy is close at hand and remains quiet, he is relying on the natural strength of his position.
[Here begin Sun Tzu's remarks on the reading of signs, much of which is so good that it could almost be included in a modern manual like Gen. Baden-Powell's "Aids to Scouting."]
19. When he keeps aloof and tries to provoke a battle, he is anxious for the other side to advance.
[Probably because we are in a strong position from which he wishes to dislodge us. "If he came close up to us, says Tu Mu, "and tried to force a battle, he would seem to despise us, and there would be less probability of our responding to the challenge."]
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.
[Ts'ao Kung explains this as "felling trees to clear a passage," and Chang Yu says: "Every man sends out scouts to climb high places and observe the enemy. If a scout sees that the trees of a forest are moving and shaking, he may know that they are being cut down to clear a passage for the enemy's march."]
The appearance of a number of screens in the midst of thick grass means that the enemy wants to make us suspicious.
[Tu Yu's explanation, borrowed from Ts'ao Kung's, is as follows: "The presence of a number of screens or sheds in the midst of thick vegetation is a sure sign that the enemy has fled and, fearing pursuit, has constructed these hiding-places in order to make us suspect an ambush." It appears that these "screens" were hastily knotted together out of any long grass which the retreating enemy happened to come across.]
22. The rising of birds in their flight is the sign of an ambuscade.
[Chang Yu's explanation is doubtless right: "When birds that are flying along in a straight line suddenly shoot upwards, it means that soldiers are in ambush at the spot beneath."]
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.
["High and sharp," or rising to a peak, is of course somewhat exaggerated as applied to dust. The commentators explain the phenomenon by saying that horses and chariots, being heavier than men, raise more dust, and also follow one another in the same wheel-track, whereas foot-soldiers would be marching in ranks, many abreast. According to Chang Yu, "every army on the march must have scouts some way in advance, who on sighting dust raised by the enemy, will gallop back and report it to the commander-in-chief." Cf. Gen. Baden-Powell: "As you move along, say, in a hostile country, your eyes should be looking afar for the enemy or any signs of him: figures, dust rising, birds getting up, glitter of arms, etc."  ]
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.
[Chang Yu says: "In apportioning the defenses for a cantonment, light horse will be sent out to survey the position and ascertain the weak and strong points all along its circumference. Hence the small quantity of dust and its motion."]
24. Humble words and increased preparations are signs that the enemy is about to advance.
["As though they stood in great fear of us," says Tu Mu. "Their object is to make us contemptuous and careless, after which they will attack us." Chang Yu alludes to the story of T'ien Tan of the Ch'i-mo against the Yen forces, led by Ch'i Chieh. In ch. 82 of the SHIH CHI we read: "T'ien Tan openly said: 'My only fear is that the Yen army may cut off the noses of their Ch'i prisoners and place them in the front rank to fight against us; that would be the undoing of our city.' The other side being informed of this speech, at once acted on the suggestion; but those within the city were enraged at seeing their fellow-countrymen thus mutilated, and fearing only lest they should fall into the enemy's hands, were nerved to defend themselves more obstinately than ever. Once again T'ien Tan sent back converted spies who reported these words to the enemy: "What I dread most is that the men of Yen may dig up the ancestral tombs outside the town, and by inflicting this indignity on our forefathers cause us to become faint-hearted.' Forthwith the besiegers dug up all the graves and burned the corpses lying in them. And the inhabitants of Chi-mo, witnessing the outrage from the city-walls, wept passionately and were all impatient to go out and fight, their fury being increased tenfold. T'ien Tan knew then that his soldiers were ready for any enterprise. But instead of a sword, he himself too a mattock in his hands, and ordered others to be distributed amongst his best warriors, while the ranks were filled up with their wives and concubines. He then served out all the remaining rations and bade his men eat their fill. The regular soldiers were told to keep out of sight, and the walls were manned with the old and weaker men and with women. This done, envoys were dispatched to the enemy's camp to arrange terms of surrender, whereupon the Yen army began shouting for joy. T'ien Tan also collected 20,000 ounces of silver from the people, and got the wealthy citizens of Chi-mo to send it to the Yen general with the prayer that, when the town capitulated, he would allow their homes to be plundered or their women to be maltreated. Ch'i Chieh, in high good humor, granted their prayer; but his army now became increasingly slack and careless. Meanwhile, T'ien Tan got together a thousand oxen, decked them with pieces of red silk, painted their bodies, dragon-like, with colored stripes, and fastened sharp blades on their horns and well-greased rushes on their tails. When night came on, he lighted the ends of the rushes, and drove the oxen through a number of holes which he had pierced in the walls, backing them up with a force of 5000 picked warriors. The animals, maddened with pain, dashed furiously into the enemy's camp where they caused the utmost confusion and dismay; for their tails acted as torches, showing up the hideous pattern on their bodies, and the weapons on their horns killed or wounded any with whom they came into contact. In the meantime, the band of 5000 had crept up with gags in their mouths, and now threw themselves on the enemy. At the same moment a frightful din arose in the city itself, all those that remained behind making as much noise as possible by banging drums and hammering on bronze vessels, until heaven and earth were convulsed by the uproar. Terror-stricken, the Yen army fled in disorder, hotly pursued by the men of Ch'i, who succeeded in slaying their general Ch'i Chien.... The result of the battle was the ultimate recovery of some seventy cities which had belonged to the Ch'i State."]