He’s making a list, he’s checking it twice, but Santa’s festive surveillance seemingly does nothing to improve children’s behaviour. Instead, it may be that wider Christmas rituals, like putting up a tree and going carolling, can prompt children to be a bit nicer – a finding that may help us better understand how religion influences behaviour.

“The question was, does belief in Santa Claus influence how children behave?” says Rohan Kapitány at Durham University in the UK. “Does this belief,…