5. From a position of this sort, if the enemy is unprepared, you may sally forth and defeat him. But if the enemy is prepared for your coming, and you fail to defeat him, then, return being impossible, disaster will ensue. 6. When the position is such that neither side will gain by making the first move, it is called _temporising_ ground. [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 enemy forestall you in occupying a pass, do not go after him if the pass is fully garrisoned, but only if it is weakly garrisoned. 10. With regard to _precipitous heights_, if you are beforehand with your adversary, you should occupy the raised and sunny spots, and there wait for him to come up. [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. § 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.