“The adaptation – excessive resistance to killing other humans – is that humans

—“The adaptation – excessive resistance to killing other humans – is that humans are dangerous predators that retaliate at high cost to themselves, whereas other creatures do not retaliate at high cost to themselves, they simply avoid taking the risk again. So we evolved for rational reasons, to both retaliate and to avoid retaliation. So it is retaliation humans fear regarding each other, and not regarding beasts. Most creatures flee losses, but humans and chimps reinforce losses purely for defensive reasons.”— Curt Doolittle