《周书·列传·卷三十》
对方必然对于通好讲和感到高兴，懈怠而减少防备，然后我们出其不意，举兵一次就可以谋取山东。
彼必于通和，懈而少备，然后出其不意，一举而山东可图。
The other party will be glad to hear about making peace, so they will relax and reduce their guard. Then we can catch them off-guard and send troops to take Shandong in one move.