Halloween is a time to celebrate ghosts, vampires, and everything supernatural.
But if you truly believe in ghosts, you're not alone.
According to a Gallup survey from 2005, about three out of four Americans harbor at least one paranormal belief. More than a third of people surveyed also said they believed in ghosts or spirits returning from the dead. Another 37% reported believing in haunted houses, and a whopping 41% in extrasensory perception (ESP).
But just what makes us susceptible to these beliefs, despite an utter lack of evidence that they're real?
It's how our brains are wired
Part of the reason many of us believe in ghosts simply comes down to the way our brains work, Barry Markovsky, a sociologist at the University of South Carolina, told Business Insider.
The human mind seeks patterns to make sense of ambiguous information. "Ghosts are almost always seen under ambiguous circumstances — such as in poor lighting, or when we're just waking up or falling asleep, when our senses are not at their peak function," Markovsky said.
People who believe in ghosts are often in situations where they're expecting to see them, such as in a "haunted" house, Markovsky added. In other words, if you're looking for something, you're more likely to find it.
"Humans are hardwired to seek out explanations for what happens around us," Radford adds.
It's related to belief in life after death
A wide variety of supernatural beliefs exist in different cultures, but ghosts are by far the most common one, Benjamin Radford, deputy editor of Skeptical Inquirer magazine and author of "Scientific Paranormal Investigation: How to Solve Unexplained Mysteries," told Business Insider.
Part of the reason for this is that believing in ghosts may be related to a belief in the afterlife, a tenet of most major religions. Believing in the supernatural also has its roots in our desire to have control over our world, Radford explained. After all, a world where random things happen is a scary one.
Another Gallup poll found that in sub-Saharan Africa, more than half of people surveyed believed in witchcraft, and those who did tended to rate themselves as less happy than nonbelievers. And a 2008 study found that lonely people are more likely to believe in the supernatural.
Some seek the thrill of it
There's a word for buying into these scary stories: legend-tripping. Basically, people do this because they know they're not in any real danger, Radford said.
But there's a contradiction at the heart of our belief in ghosts. One the one hand, there's the idea that ghosts are scary and wish to do us harm, but on the other, there are people who go looking for ghosts.
Many ghost hunters see themselves as "traffic cops for the afterlife," Radford said. Instead of believing ghosts to be evil, they think of them as spirits that have simply gotten lost on the way to the hereafter.
As Radford put it, "If you're genuinely terrified of ghosts and think they could kill you, why the [heck] would you go looking for them?"
Of course, movies and TV shows about ghost-hunting, which are often presented with very little skepticism, aren't helpful.
It's all good fun, but as Radford said, "Don't believe everything you see on TV!"
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