The InterDependence Project
Confusion over just what constitutes our human nature is at the very heart of the problem. Virtually all the beliefs about human nature are actually beliefs about our culture. Our culture is not our nature and I maintain that our culture actually creates an incredibly perverse world that is diametrically opposed to our true nature.
If you really want to get some clues to the true nature of a bear - you certainly don't go down to the zoo. We've engaged in something along the same lines by basing our theories about the nature of man by observing us in our contemporary cage of culture.
Fortunately in our case, there are hunter-gatherer cultures that have been studied and even a hand full of them that are still around.