A farmer had five female pigs. Times were hard, so he took them to the county fair to sell. At the fair, he met another farmer who owned five male pigs. After talking a bit, they decided to mate the pigs and split everything 50/50. But since the farmers lived sixty miles apart, they agreed to drive thirty miles each, find an empty field, and let the pigs mate.
The first morning, the farmer with the female pigs got up at 5 A.M., loaded the pigs into the family station wagon, the only vehicle he had, and drove the thirty miles.
"How will I know if they are pregnant?” he asked the other farmer.
"If they're lying in the grass in the morning, they're pregnant. If they're in the mud, they're not.”
The next morning the pigs were rolling in the mud. So he hosed them off, loaded them into the station wagon, and drove the thirty miles to the empty field to try again.
This continued each morning for more than a week.
The next morning he was too tired to get out of bed.
"Honey,” the farmer said to his wife. “Please look outside and tell me whether the pigs are in the mud or in the grass."
"Neither,” yelled his wife. "They're in the station wagon and one of them is honking the horn."