"There is an often told story of a boy who
found two ripe apples as he was walking home
from school with a friend. He kept the larger one
for himself, and gave the smaller one to his friend.
"It wasn't fair to keep the larger one for yourself",
the friend replied. "What would you have done?",
the first boy asked. "I'd have given you the larger
one and kept the smaller one for myself", said the friend.
To which the first boy responded, "Well,
we each got what you wanted, so what are you
complaining about?" (Rabin, 1998)
Yes, I'm following a course in behavioral economics.