An institution for the mentally ill arranged for its inmates to attend a baseball game. The director spent days training the patients to obey his commands, so there wouldn't be any trouble.

The day of the game was bright and sunny and the group arrived just before the first pitch. When it was time for the National Anthem, the director yelled, "Up, nuts!" and the inmates immediately rose. When the National Anthem was over, the director yelled, "Down, nuts!" and the inmates sat.

The game proceeded and the inmates were well-behaved. When the home team made a good play, the director yelled, "Clap, nuts!" and the patients applauded just like normal fans.

Things were going so well that the director left his seat to go get a hot dog and a beer. But when he came back, there was a riot going on.

The director finally located his assistant and demanded, "What happened?"

"Everything was fine," the assistant said, "until some guy came over and yelled, 'Pea-nuts'!