"I doubt religion is responsible for as much death as is claimed. Some people love to fight and steal and dominate – that's the key. There are arseholes among us and, given half a chance, they're going to start some sort of trouble out of ruthless self-interest or bloodlust or both. The prevailing ethos of any surrounding society is almost always that you're not supposed to kill people without a good reason, or at least some sort of reason. But the arseholes are clever, so they come up with reasons. To deeply religious societies, religious differences sound like a very convincing reason to kill people. But that doesn't mean the killing wouldn't have been happening anyway."