When you think of religion, you probably think of a god who rewards the good and punishes the wicked. But the idea of morally concerned gods is by no means universal. Social scientists have long known that small-scale traditional societies – the kind missionaries used to dismiss as “pagan” – envisaged a spirit world that cared little about the morality of human behaviour. Their concern was less about whether humans behaved nicely towards one another and more about whether they carried out their obligations to the spirits and displayed suitable deference to them.