宋代沈括所著《梦溪笔谈·权智》中,讲了这样一个故事:北宋名将曹玮有一次率军与吐蕃军队作战,初战告胜,敌军溃逃。曹玮故意命令士兵驱赶着缴获的一大群牛羊往回走。牛羊走得很慢,落在了大部队后面。有人向曹玮建议,“牛羊用处不大,又会影响行军速度,不如将它们扔下,我们能安全 SONG GUO SONG GUO “Meng Xi Bi Tan rights”, tells the story of a famous leader of the Northern Song Dynasty Cao Wei led troops to fight with the Tubo army, the initial victory, the enemy fled. Cao Wei deliberately ordered the soldiers to drive away the seized fleet of cattle and sheep. Cattle and sheep go very slowly, fell behind the large forces. Someone suggested to Cao Wei that "if cattle and sheep are of little use, their march speed will be affected. It is better to throw them off and we can safely