齐国的晏子出使到楚国，楚王有意当着晏子的面侮辱齐国。
一天，楚王摆了酒席招待晏子。正当他们吃得高兴的时候，两个小官押着一个犯人来见楚王。
楚王故意问道：“这人犯了什么罪?”
小官回答说：“他说一个强盗。”
楚王又问：“他说哪一个国家的人?”
小官回答：“他说齐国人”
楚王回头对晏子说：“原来齐国人惯于当强盗的。”
晏子站起来答道：“大王，我听说生长在淮南的橘树，移植到淮北就会变成枳树。吃外表上看，橘树和枳树的叶子是一样的。但是这两种树的果子的味道却完全不同。我们齐国的老百姓从来不做强盗，一到楚国就干起犯罪的勾当来了。我看，这也许是受这里水土的影响吧!”
楚王听了，羞愧得连一句话都说不出来。
Yan Zi of the state of Qi was sent on a mission to the State of Qi to Yan Zi's face.
One day, the King of Chu gave a banquet for Yan Zi. Just when they were enjoying it, two petty officials brought a convict to the king.
Deliberately the King of Chu asked: "What crime has this man committed?"
One of the petty officials answered: "He robs."
Again the King of Chu asked: "Where is he from"
The petty official answered: "He is from the State of Qi."
The King of Chu turned to Yan Zi and said: "So the people of the State of Qi are used to committing robbery."
Yan Zi stood up and replied: "Your Majesty, I heard that when orange trees grown in the south of the Huai River are transplanted to the north of Huai River, they become trifoliate orange trees. Outwardly the leaves of orange trees and those of trifoliate orange trees look alike, but the tastes of their fruits are entirely different. Our people of the State of Qi never commit robbery, but once they come to the State of Qi never commit robbery, but once they come to the State of Chu, they start to engage in criminal activities. I think, maybe this is the effect of the environment and climate here."
As the King of Chu heard this, he was truck dumb with shame.