《战国策·燕二·或献书燕王》
以上三件事，是常人所能做到的，山东各国的国君却不能领悟，这是臣下为山东各国感到遗憾的。
三物者，人之所能为也，山东之主遂不悟，此臣之所为山东苦也。
The three things mentioned above are within the capabilities of ordinary people. However, the rulers of Shandong cannot understand them, which the subjects of Shandong regret.