FORGOTTEN HISTORY: Irrational fears came true | History Defined

Some of these fears are quite specific, like the fear of moths or cheese graters. But these fears, and even phobias, are more common than we might think. The National Institute of Mental Health (NIMH) estimates that roughly 12.5% of adults in the United States experience a specific phobia at some point in their lives.

In fact, specific phobias are among the most common anxiety disorders worldwide. They can include animal phobias, such as zoophobia (fear of animals in general) or more specific fears, like fear of dogs. There are also situational phobias, like the fear of driving on highways, as well as social anxiety-related fears.

Curiously, some of these fears are considered irrational because they often involve things unlikely to harm us directly. Psychologist Martin Seligman explains that humans rarely develop phobias of modern hazards like cars or electrical outlets, yet we can easily develop fears of heights, water, and even enclosed spaces.

According to this theory, our brains are predisposed to fear threats that could have harmed our prehistoric ancestors, rather than necessarily focusing on modern dangers. So things like dark caves, sudden drops, and rustling bushes can be enough to scare our brains, even when there's no real threat.

If we look at the numbers, these fears are also quite reasonable. Persi Diaconis and Frederick Mosteller came up with the Law of Truly Large Numbers, which suggests that, mathematically, given a large enough number of events, even the most outrageous coincidences are likely to happen.

This means that if millions of people check and shake their shoes every morning, the chances of someone finding a dangerous spider, a scorpion, or even a snake increase significantly. Meanwhile, if you're the only person checking your shoes every morning, the chances of finding one are much lower.

Ultimately, though, these irrational fears aren't entirely irrational. Not because the chances of them happening are high, but because the human mind and brain work in peculiar ways. Neuroscientist Karl Friston describes the human brain as a “prediction machine” that runs low-power simulations of what might happen next.

So, if an irrational fear does end up coming true, it can trigger what neuroscientists call a “catastrophic prediction error.” When the seemingly impossible actually happens, the brain can experience something like a sensory shockwave, leading to existential horror rather than just fear.