In the original version of the German fairytale, when the witch caught Hansel and Gretel eating her gingerbread cottage, she forced Gretel into slavery, but decided that she would eat Hansel. To this end, she locked the boy in a cage and began to force-feed him so that he would be “fat enough” to eat.

Not only was the witch ignorant to the health benefits of eating lean meat, she was also mostly blind, and so, each day, she would ask Hansel to stick his finger out for her to feel just how fat he was getting. Hansel, in fact, grew quite fat in the cage, but to fool his captor, he used what is described in the tale as a “clever trick”: he would hold out a bone instead of his finger. The witch, feeling the bone, decided that the boy was still too skinny to eat, and Hansel would survive another day.

But what if the witch had decided that she needed more evidence?

Of course, the idea of cannabilism is truly horrifying. But in its context as a fairy-tale parable, it is interesting to note that Hansel’s “clever trick” relied upon the witch engaging in the fallacy of observational selection, and using that fallacy in his favor, as well. Observational selection happens when someone making a decision – such as whether or not Hansel was fat enough to eat – only chooses a limited set of data to back up their reasoning.

observational selection in Hansel and GretelWe all engage in observational selection from time to time, choosing what data to believe, what stories to read, which studies to believe. Usually, we choose our data according to what we already believe, dismissing those people and ideas that clash with our own established worldview (confirmation bias). So the fact that the witch was satisfied with such a small amount of evidence, only feeling what she thought was the boy’s finger, seems to indicate that she had, perhaps, lost her taste for roasted children: had she been truly anxious to cook Hansel for her dinner, she would have insisted on more data, reaching into in the cage to feel the boy’s belly as well, and Hansel would have been lost. Hansel gambled his life on the chance that the witch would not investigate further.

But, as wrong as the fairytale witch was for roasting and eating children, we can take the lesson of observational selection from this story and remember that if we want to find out the whole truth, we must explore all the evidence, no matter whether or not it agrees with our previous conceptions. Only in getting all the relevant facts before making a decision can we truly practice healthy skepticism and defend ourselves and others from the tricks of predatory people.

Editor's Note: While we at OMF value all free expression of opinion, the views expressed by our contributing authors are their own and do not necessarily reflect the opinions of OMF, its board members, or trustees.

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