《三国志·蜀书·刘彭廖李刘魏杨传》
退下后他告诉别人： 角这个字，是刀下加一个用，头上用刀，是非常凶险的。 
退而告人曰： 角之为字，刀下用也；头上用刀，其凶甚矣。 
After he stepped down, he told others: “The word “角” is a knife with a “用” underneath. Using a knife on the head is very dangerous.”