A man is passing Farmer Gile's farmyard when he spots a pig with a wooden leg, "I say," asks the man, "why has your pig got a wooden leg?"
The farmer says, "Well he's a very special pig that one. One night, the wife and me were asleep when the pig spots that the farm was on fire. He broke down the door with his little trotters then ran up the stairs to drag me to safety. Then he went back through the flames and smoke to fetch my wife and back in again to save the children. It's all thanks to that pig that we're here today."
"I see," says the man, "so he hurt his leg in the fire did he?"
"Oh no, " says Farmer Giles, " but you see, when you've got a pig as special as this one, you don't want to eat it all at once."
On a serious note, this about sums up much of the human race in my view.