《智囊(选录)·兵智部·耿弇》
耿弇说： 西安县城听说我军将要进攻他们，必定会加强防备，但是我军出其不意地进攻临淄城，临淄的守兵一定会因为没有料到而惊慌失措，因此能立即破城。临淄城一破，西安城就陷入了孤立无援的境地，这也就是为什么只攻一城而得到两城的原因。
弇曰： 西安闻吾攻，必严守具；临淄出不意而至，必自警扰，攻之，必立拔；拔临淄则西安孤，此击一而得二也!
Geng Yan said: The Xi'an county city will definitely strengthen its defence after hearing that our army is going to attack them. However, if our army attacks Linzi city by surprise, the defenders in Linzi city will be panic-stricken because they do not expect it. Therefore, the city can be captured immediately. Once Linzi city is captured, Xi'an city will be isolated and helpless. This is the reason why we only attack one city but get two cities.