Would you believe that the old story of Hansel and Gretel was based in fact?

In 1963, Hans Trexler published a book I’m surprised that Oliver Hartwich hasn’t read: Die Wahrheit über Hänsel und Gretel.

Trexler told the story of Georg Ossegg, an amateur archaeologist and teacher. As a child, Ossegg had loved an ancient early illustrated copy of the Grimm fairy tales. Decades later, a spot in the woods looked eerily familiar.

He realised that he was standing in one of the illustrations from that old book.

If the story were true, and he had found the path the children had followed, where would their home have been? He found the spot, now part of a motorway. Archival records said an old hut had been purchased in just that spot to make room for the road.

He traced further. He found the clearing where the fire must have been built to warm the children. After days of searching, he found the tree to which the father had tied a branch to sway in the wind and make a noise like a woodcutter’s axe, to reassure the abandoned children. Radiocarbon dating of the rope, now meters up the tree, placed it in the 1640s.

After careful sleuthing, he found the brick base of an old oven where the witch’s hut must have been. Inside, the charred remnants of a woman’s skeleton – but academics concluded that the young murdered woman had been strangled before being burned. A bent iron hinge suggested the hut had been broken into.

Finally, he found, in a hidden chest, a recipe for gingerbread.

Ossegg scoured ancient town records. Hänsel und Gretel were not children at all, but murderous rival bakers after a secret recipe.

Trexler’s book sold hundreds of thousands of copies and earned rave reviews. But despite several obvious absurdities and impossibilities worked into the text, and despite that Ossegg was entirely fictional, people believed it.

Trexler had meant to send up popular charlatans of the time purporting to find evidence for ancient myths. He wanted people to think more carefully.

But he had provided a story just sciency enough for people to believe it without thinking.

Satire can be helpful vaccination against falsehood, as Tim Harford’s excellent Cautionary Tales podcast, where I first heard this story, points out.

If only more people who have believed falsehoods about vaccinations had had such protection.