When Nasreddin was a boy, he never did what he was told, so his father always told him to do the opposite of what he wanted him to do.
One day, when the two were bringing sacks of flour home on their donkeys, they had to cross a shallow river. When they were in the middle of it, one of the sacks on Nasreddin's donkey began to slip, so his father said, "That sack is nearly in the water! Press down hard on it!"
His father of course expected that he would do the opposite, but this time Nasreddin did what his father had told him to do. He pressed down on the sack and it went under the water. Of course, the flour was lost.
"What have you done, Nasreddin?" his father shouted angrily.
"Well, Father", said Nasreddin," this time I thought that I would do just what you told me, to show you how stupid your orders always are."