《智囊(选录)·兵智部·荀罂 伍员》
荀偃说： 应该继续围攻郑国，等到楚国救郑的时候，就可以迎战楚军；如果现在和郑国议和，就不会得到实际的利益。 
荀偃曰： 遂围之，以待楚人之救也，而与之战。不然，无成。 
Xun Yan said: We should continue to besiege the state of Zheng and wait until the state of Chu comes to the rescue of Zheng. Then we can fight the state of Chu. If we make peace with the state of Zheng now, we will not get any real benefits.