Imagine that you are babysitting a 6-year-old and an 8-year-old. The parents have left some treats for dessert: two bananas, a lollipop, and an ice cream bar. The parents instructions were to allow each child to choose one treat. Unfortunately, both kids want the ice cream bar. How can you distribute the goods fairly? The easiest way would be to give them each a banana. But, neither wants a banana. Or, perhaps the older child should have first pick because she has more responsibilities. Or, perhaps the younger child should have first pick because he has less opportunities. Perhaps they should compete for first pick. But, that seems to give the older child an automatic advantage again. Perhaps you could split the ice cream bar in half, but then they should be allowed to split something else, and the only other thing they want is the lollipop, which is hard to split. As you can see, this is a complicated problem. How would you solve it?