There were once two crows who were fierce rivals.
One day, one of the crows said to the other, "You realize, of course, that I can fly much higher than you can."
"Don't be ridiculous." the other crow said. "Everyone knows that I can fly much higher than you."
"No, you can't." the first crow said.
"Yes, I can." the second crow replied,fly and the argument went on and on.
At last, they decided to have a contest to settle the argument.
"We will compete to find out who can fly the highest while carrying a sack." the first crow said.
They argued for some time over the size of the sack, but eventually came to an agreement.
Then there was further argument about what each sack would contain.
Finally, they agreed that the first crow would fill his sack with cotton and the second crow would fill his with salt.