[The general meaning of the last phrase is doubtlessly, as Tu Yu says, "not to allow the enemy to cut your communications."In view of Napoleon's dictum, "the secret of war lies in the communications," [1] we could wish that Sun Tzu had done more than skirt the edge of this important subject here and in I. ss.
10, VII. ss. 11. Col. Henderson says: "The line of supply may be said to be as vital to the existence of an army as the heart to the life of a human being. Just as the duelist who finds his adversary's point menacing him with certain death, and his own guard astray, is compelled to conform to his adversary's movements, and to content himself with warding off his thrusts, so the commander whose communications are suddenly threatened finds himself in a false position, and he will be fortunate if he has not to change all his plans, to split up his force into more or less isolated detachments, and to fight with inferior numbers on ground which he has not had time to prepare, and where defeat will not be an ordinary failure, but will entail the ruin or surrender of his whole army." [2]
Then you will be able to fight with advantage.
4. Ground which can be abandoned but is hard to re-occupy is called ENTANGLING.
5. From a position of this sort, if the enemy is unprepared, you may sally forth and defeat him. But if the enemy is prepared for your coming, and you fail to defeat him, then, return being impossible, disaster will ensue.
6. When the position is such that neither side will gain by making the first move, it is called TEMPORIZING ground.
[Tu Mu says: "Each side finds it inconvenient to move, and the situation remains at a deadlock."]
7. In a position of this sort, even though the enemy should offer us an attractive bait,[Tu Yu says, "turning their backs on us and pretending to flee." But this is only one of the lures which might induce us to quit our position.]
it will be advisable not to stir forth, but rather to retreat, thus enticing the enemy in his turn; then, when part of his army has come out, we may deliver our attack with advantage.
8. With regard to NARROW PASSES, if you can occupy them first, let them be strongly garrisoned and await the advent of the enemy.
[Because then, as Tu Yu observes, "the initiative will lie with us, and by making sudden and unexpected attacks we shall have the enemy at our mercy."]
9. Should the army forestall you in occupying a pass, do not go after him if the pass is fully garrisoned, but only if it is weakly garrisoned.
10. With regard to PRECIPITOUS HEIGHTS, if you are beforehand with your adversary, you should occupy the raised and sunny spots, and there wait for him to come up.
[Ts`ao Kung says: "The particular advantage of securing heights and defiles is that your actions cannot then be dictated by the enemy." [For the enunciation of the grand principle alluded to, see VI. ss. 2]. Chang Yu tells the following anecdote of P`ei Hsing-chien (A.D. 619-682), who was sent on a punitive expedition against the Turkic tribes. "At night he pitched his camp as usual, and it had already been completely fortified by wall and ditch, when suddenly he gave orders that the army should shift its quarters to a hill near by. This was highly displeasing to his officers, who protested loudly against the extra fatigue which it would entail on the men. P`ei Hsing-chien, however, paid no heed to their remonstrances and had the camp moved as quickly as possible. The same night, a terrific storm came on, which flooded their former place of encampment to the depth of over twelve feet. The recalcitrant officers were amazed at the sight, and owned that they had been in the wrong.
'How did you know what was going to happen?' they asked. P`ei Hsing-chien replied: 'From this time forward be content to obey orders without asking unnecessary questions.' From this it may be seen," Chang Yu continues, "that high and sunny places are advantageous not only for fighting, but also because they are immune from disastrous floods."]
11. If the enemy has occupied them before you, do not follow him, but retreat and try to entice him away.
[The turning point of Li Shih-min's campaign in 621 A.D.
against the two rebels, Tou Chien-te, King of Hsia, and Wang Shih-ch`ung, Prince of Cheng, was his seizure of the heights of Wu-lao, in spike of which Tou Chien-te persisted in his attempt to relieve his ally in Lo-yang, was defeated and taken prisoner.
See CHIU T`ANG, ch. 2, fol. 5 verso, and also ch. 54.]
12. If you are situated at a great distance from the enemy, and the strength of the two armies is equal, it is not easy to provoke a battle,[The point is that we must not think of undertaking a long and wearisome march, at the end of which, as Tu Yu says, "we should be exhausted and our adversary fresh and keen."]
and fighting will be to your disadvantage.
13. These six are the principles connected with Earth.
[Or perhaps, "the principles relating to ground." See, however, I. ss. 8.]
The general who has attained a responsible post must be careful to study them.
14. Now an army is exposed to six several calamities, not arising from natural causes, but from faults for which the general is responsible. These are:(1) Flight; (2)insubordination; (3) collapse; (4) ruin; (5) disorganization; (6)rout.
15. Other conditions being equal, if one force is hurled against another ten times its size, the result will be the FLIGHTof the former.
16. When the common soldiers are too strong and their officers too weak, the result is INSUBORDINATION.
