Sugar doesn't make you hyper. A penny dropped from the top of the Empire State Building won't kill you. We don't just have five senses. Napoleon wasn't short. Caffeine doesn't dehydrate you. The Great Wall of China is not visible from space.

Everything you know isn't wrong. But a lot of it is.

Myths are everywhere: on the Internet, at your work, in your head. Even worse, they're difficult to dislodge. Psychologist Stephan Lewandowsky at the University of Bristol has made a career out of trying to loosen their extensive hold. After decades of effort, he's learned a lot. His biggest discovery, perhaps, is that attempting to debunk a myth can backfire, resulting in the myth being strengthened instead of removed.

He also disproved a huge myth about debunking myths: "that removing [a myth's] influence is as simple as packing more information into people's heads."

It's simply not that easy.

"This approach assumes that public misperceptions are due to a lack of knowledge and that the solution is more information - in science communication, it’s known as the 'information deficit model'," Lewandowsky wrote in The Debunking Handbook. "But that model is wrong: people don’t process information as simply as a hard drive downloading data."

Often, the problem is not a lack of information, but too much of it. With such a bounty now available, both of credible and dubious origins, people can pick the "facts" that fit their preferred ideology or worldview. How is the layperson to tell truth from untruth?

Lewandowsky has some recommendations.

"To successfully impart knowledge, communicators need to understand how people process information, how they modify their existing knowledge and how worldviews affect their ability to think rationally. It’s not just what people think that matters, but how they think," he says.

To the human mind, facts are minutiae. What matters most is the overarching narrative. For a single fact or even a group of facts to topple a mindset is an immense task, like David facing off against Goliath... if Goliath was twice as tall and encased in graphene body armor.

So to help dispel a myth, use these three steps. First, emphasize the core facts of the topic without even mentioning the misinformation. Take the 10% brain myth, for example. Simply say, "humans make complete use of our brains, this is clearly demonstrated with brain scan technology." Second, state the myth, but first preface it with an explicit warning. "There is a lot of pervasive misinformation about the brain. For example, 65% of the public falsely believes that we only use 10% of our brainpower." Third, present an alternative explanation for why the myth is wrong. Neuroscientist Barry Beyerstein can help here: "Brain cells that are not used have a tendency to degenerate. Hence if 90% of the brain were inactive, autopsy of adult brains would reveal large-scale degeneration." Yet we don't see this.

One myth down, a multitude to go.

Source: The Debunking Handbook, by Stephan Lewandowsky and John Cook

(Image: Shutterstock)