Bertie was a milkmaid. Her brother was a cowherd. One day, her brother said, “Bertie, take the cows out for grazing today. Remember, we have ten cows.” Bertie was a simpleton. She kept counting the cows frequently to ensure there were ten of them. After reaching the meadow, she sat on a cow. Then she began counting. She counted from one to nine and said, “We had ten cows. But there are just nine. Where is the tenth cow?” Then she got off the cow and walked around the meadow, counting each cow carefully. She saw all the ten cows and was relieved. Bertie then sat on a cow. When she counted them, there were just nine. When she got off the cow, there were ten. “The cows are playing hide-and-seek,” she said. Bertie did not realise that she always forgot to count the cow she was sitting on!