《史记·七十列传·苏秦列传》
燕王说： 齐国本来就是我的仇敌，是要讨伐的国家，只是担心国家衰弱，没有足够的力量。
王曰： 夫齐者固寡人之雠，所欲伐也，直患国敝力不足也。
King Yan said: Qi was originally my enemy, a state that must be punished. It's simply that I'm worried that my state is too weak, and lacks the strength.