Why We Don't Compromise.

I see the root of most of the problems in the world as a struggle between villages. Imagine that you live in one of two villages that must share land and water. There are three main options in this case:
1) Let the other village have everything, while your village starves or moves far away.
2)Take, by force if necessary, all the resources. Let the other village starve. (This could backfire, sending your village back to option 1)
3) Compromise and share resources.

That pretty much covers the options. When starvation is the option, people are forced to cooperate with each and share. This is done by compromise, sometimes called "mutual amputation." Neither side will EVER end up with everything it wants. But, if they try sometime, they just might find, they get what they need.

In the case of the villages, people will end up negotiating face to face and coming to an agreement or they probably won't survive long. This means that social evolution will automatically select people who can compromise and share. Well, not quite, because the genes that survive are determined almost entirely by who has resistence to a plague, or who can stay isolated from those who have the plague. Meaning that in time of plague, being selfish might keep you alive.

Like metamorphic rock subject to the forces of famine and plague, our civilization was formed. Hunter gatherers seldom suffered from famine and plague. The total population and the extremely low density of population kept the demand synchronized with the resources via small, incremental adjustments. Disease of any kind was hard to spread when small bands roamed the Earth, seldom interacting with others.

Hunter gatherers may have benefitted from cooperation with other groups, but they just as easily could have been seriously hurt in the process, since hunter-gatherer bands never viewed each other as equals. My tribe is "the people," yours is something less than that.

Modern civilization has changed the available options, at least in first-world countries or among the wealthy. In many cases, these people are so far removed from hunting or growing their own food that there seldom appears to be any survival-based need for compromise, and certainly not face-to-face.