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One morning Nasreddin left his house with six donkeys to go to the market. After a time, he got tired and got on to one of them. He counted the donkeys, and there were only five, so he got off and went to look for the sixth. He looked and looked but did not find it, so he went back to the donkeys and counted them again. This time there were six, so he got on to one of them again and they all started. After a few minutes he counted the donkeys again, and again there were only five! While