By Sarah-Jane O'Connor 21/12/2015

Spoiler warning: Kids’ willingness to believe in Santa Claus diminishes as they become more knowledgeable about the world and the physical implausibility of Santa’s magical acts.

Researchers from Los Angeles’ Occidental College tested children’s willingness to accept on trust the story of Santa Claus and his miraculous one-night round-the-world trip.

Much of what we know comes from the testimony of others, the authors say. “Few adults have dissected a human body or performed astronomical calculations, yet most still know that the liver is in the abdomen and that the Earth orbits the sun.”

Crucial, though, is that the information comes from someone we trust.

For kids, it’s simple: they trust their parents. But when it comes to Santa Claus, the testimony is not only false (so say the researchers) but also highly implausible. Santa’s actions break many physical laws: visiting every child’s house in a single night, fitting down chimneys (and into houses without fireplaces), and somehow staying aloft in a sleigh. Oh, and the flying reindeer.

Yet, previous research has shown that children believe in Santa Claus more strongly than any other fictional character and do so until they are about eight- or nine-years-old. But no-one is quite sure what tips the balance into disbelief. When asked, most children say they worked it out on their own, rather than being told by someone else.

For the current research, published in Cognitive Development, children between the ages of three and nine were asked to write letters to Father Christmas, asking how he accomplished his many fanciful feats. They were also asked to explain how he did these things and to weigh up whether things that contravened physical laws were possible.

While all the children believed in Santa, older children (8-9 years) were beginning to think about Father Christmas on a conceptual level, questioning how he did what he did. They were also able to distinguish between things that were impossible (could someone walk through walls?) and things that were possible but improbable (could someone grow a beard down to their toes?).

The researchers concluded that as children became better at differentiated the impossible from the improbable, they also started to question the feasibility of Santa’s extraordinary abilities.

While children come to believe in Santa because of the weight of testimony – they are told often and consistently the story of Santa Claus – they begin to disbelieve in him because their understanding of the world has developed to a point they realise the physical improbabilities of the jolly man in the red suit.

So, parents, it might be sad when your little one no longer believes in the magic of Santa Claus. But don’t despair; instead, reassure yourself that the wee tyke has taken a big step in learning to weigh up facts and come to conclusions about their world.

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Featured image: Flickr CC, martinak15.