Mi Heng was recommended to Cao Cao when the latter needed someone to lobby Liu Biao to expand his influence. However, Mi Heng felt slighted and took his anger out on Cao Cao's subordinates.
One day, at a banquet for distinguished guests, Cao Cao ordered Mi Heng to serve as a drummer to humiliate him. Mi Heng arrived dressed in rags. When questioned, he stripped naked and stood proudly before the assembly, causing the guests to avert their eyes in embarrassment.
Cao Cao angrily rebuked him. Mi Heng retorted, "You call me shameless? It is not I, but one who has misled his majesty. Let all witness my clean conscience."
"If you are clean," Cao Cao roared, "then who is dirty?"
"You!" Mi Heng sneered. "Your eyes are dirty for failing to distinguish good from evil. Your mouth is dirty for speaking without knowledge. Your ears are dirty for refusing counsel. Your body is dirty for knowing no history. Your belly is dirty for harboring no tolerance."
Infuriated, Cao Cao sent him to the battlefront, hoping the enemy would kill him.