Two students of one economist were walking down the street one day when they passed one large piles of dog s h i t.
The first one said to the other, "I'll pay you $1 billion to eat one of those piles of s h i t." The second one agrees and chooses the piles and eats it. The first onepays him his $1 billion.
A few minites late, they passed another one large piles of dog s h i t, then the second one says, "I'll pay you $1 billion to eat this pile of s h i t." The first one says okay, and eats the s h i t. The second pays him the $1 billion.
They resume walking down the street.
After a while, the second student says, "You know, I don't feel very good" , then they ask their teacher, "We both have the same amount of money as when we started. The only difference is we've both eaten s h i t."
The teacher economist says: "Ah,I am proud for you, you only eat two s h i t, but engaged in $2billion worth of trade and $2billion GDP!"
