David Pinsof writes: I believe people are motivated purely by self-interest, family-interest, and group-interest. No other motives exist because no other motives can survive the Darwinian process…
A gene for nepotism causes its carriers to lavish resources on genetic relatives, who are especially likely to share a copy of the gene for nepotism. Such a gene will spread when the benefit to the nepotist’s kin, multiplied by the probability of them sharing the nepotistic gene, outweighs the cost to the nepotist. It’s a kind of Darwinian accounting.
Then there’s group-interest. A gene for loyalty causes its carriers to selectively help specific people—i.e., allies—who can be trusted to help the carrier in return. Such a gene will spread when the expected benefit of getting helped outweighs the cost of helping. The benefit of having allies back you up in conflicts, for example, outweighs the cost of occasionally backing up your allies. More Darwinian accounting.
But not everyone can be an ally of everyone. Being loyal to one side means spurning the other. And resources are limited, so when you and I get more stuff (like power and status), we’re taking it away from someone else. And fitness is relative—it’s about who’s out-reproducing whom—so when our fitness goes up, someone else’s goes down. Which means hurting our rivals and helping our allies go hand in hand. Ergo, tribalism.
So we have arrived at the unholy trinity of human nature: self-interest, family-interest, and group-interest.
