Verse 4-Wei Liao Zi Art of War Chapter 6
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Verse 4-Wei Liao Zi Art of War Chapter 6
English
If an army of a hundred thousand is encamped beneath the city walls, the reinforcement must break open the siege, and the city’s defenders must go out to attack. When they move forth, they must secure the critical positions along the way. But the reinforcement to the rear of the besiegers should not sever their supply lines, and the forces within and without should respond to each other. This sort of rescue display a half-heated commitment and we can await for the opportunity to topple the attackers. To deal with the reinforcement, the enemy general will put their stalwarts in the rear, and place the old in the forefront. Then the enemy will not be able to advance, nor be able to stop the defenders from breaking out. This is what is meant by the 'tactical balance of power in defense'.
Modern
敌人十万大军兵临城下，援军必须能打开重围，守军也必须能乘机出去，抢占要点。援军也可以只在敌军的后方打开一条通路，使军的粮道不被切断，并与守军互相策应，这是为了表示救援不积极用以迷惑敌人，等待有利战机。敌人为了对付援军，只好把精部队撤到后方控制起来，而把战斗力差的部队配置在攻城前线，这样敌人攻城，就不可能有进展，而守军也可以出去了。这就是守城的权变。
Original
十万之军顿于城下，救必开之，守必出之，据要塞。但救其后，无绝其粮道，中外相应，此救而示之不诚，则倒敌而待之者也。后其壮，前其老，彼敌无前，守不得而止矣。此夺权之谓也。
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From: Wei Liao Zi Art of War Chapter 6