Forty-nine years ago, the Apollo 11 spacecraft delivered the first astronauts to the surface of the moon. The footprints Buzz Aldrin left in lunar soil are still around — and so are the throngs of conspiracy theorists who claim the entire landing was faked.

For one thing, they argue, the flag the crew planted seemed to flutter in videos, which shouldn't happen since there's no wind on the moon. Besides, wouldn't mini-meteors have killed the astronauts the moment they ventured outside?

The "moon landing hoax" was among the first conspiracy theories to gain traction with the American public. In the years since, the theories have multiplied like jack rabbits, swarming all corners of the cultural landscape.

After the terrorist attacks of Sept. 11, 2001, some fringe activists insisted the U.S. government, rather than al-Qaeda, had planned the attacks.

Conspiracies about President Trump's ties to Russia compete with all the real news on the topic. "Pizzagate" conspiracists claimed Hillary Clinton was operating a pedophile ring in a D.C. pizza parlor, leading one true believer to fire a gun in the restaurant. It's tempting to dismiss conspiracy theorists as wearers of tinfoil hats.

But the theories should be taken seriously for their effects on political and social discourse — and research suggests that, under the right circumstances, many people are susceptible to their allure. While people's attraction to conspiracy theories might seem illogical, it stems from a very logical desire to make sense of the world.

Assigning meaning to what happens has helped humans to thrive as a species, and conspiracy theories are internally cohesive stories that "help us to understand the unknown whenever things happen that are fearful or unexpected," said Jan-Willem van Prooijen, a social psychologist at Vrije University in Amsterdam.

For some believers, the sense of comfort and clarity such stories bring can override the question of their truth value. Conspiracy theorists often have a high degree of tolerance for contradiction that allows them to ignore evidence against their theories.

In one study at the University of Kent in the United Kingdom, people who said Osama bin Laden had died before the U.S. raid on his compound were also more inclined to say he was still alive. The stories might have clashed, but both versions denied the Obama administration's report that bin Laden had been killed during the raid.

Conspiracy theories also supply a seductive ego boost. Believers often consider themselves part of a select in-group that — unlike the deluded masses — has figured out what's really going on.

In a study at Johannes Gutenberg University in Germany, belief in conspiracy theories was stronger among people who said they wanted to stand out from the crowd.

People with a high "conspiracy mentality" also expressed more belief in a conspiracy theory when they were told a minority of survey-takers believed it, as opposed to a majority.

Rejection and hardship can intensify people's need to believe a story that empowers them or justifies their situation, whether the story is true.

People who are dissatisfied with the state of the world — such as the unemployed or those who support extreme ideologies — are highly vulnerable to conspiracy theories, van Prooijen said: "If people are satisfied, they are less likely to pursue this sort of theory."

While conspiracy theories have been around for millennia, they are thriving in a political moment that rewards those who reject established knowledge.

"Conspiracy theories are becoming part of our national dialogue," said University of Miami political scientist and conspiracy theory researcher Joseph Uscinski.

When such theories become entrenched in the public consciousness, however, they erode people's trust in authorities and the status quo. In a vicious cycle, that creates fertile ground for the emergence of ever more outlandish conspiracy theories.

Part of the foundation of democracy, as writer Stephen Harrington points out, is a broad consensus about basic facts that persists even when the meaning of these facts is hotly debated.

But conspiracy theorists operate from a set of facts untethered to reality, and people who call their bluff are often ignored or labeled as part of the proposed conspiracy.

When people believe "there is no credible source of news," said Peter Kreko, director of the Political Capital institute in Budapest, "there can be no real source of debunking."

In 2016, Kreko and his colleague, social psychologist Gabor Orosz of Budapest's Eötvös Loránd University, tested the usefulness of various ways to counter conspiracy theories. First, they played participants a recording of a conspiracy "super-theory" stating that Jews, bankers and the European Union were exploiting Hungary.

Then the researchers tried three debunking strategies: rationally arguing against the conspiracy theory; ridiculing those who believed in the theory; and empathizing with the people the theory targeted. It turned out that both rationality and ridicule were somewhat effective in reducing participants' belief in the theory, while empathy was largely ineffective.

Showing concern for a conspiracy theory's victims, the study suggests, isn't a good debunking strategy — especially when the theory is racist, discriminatory or otherwise harmful. What's the best way to put effective pushback tactics into practice?

(Aldrin once punched someone who accused him of faking the moon landing, but that's probably not the best solution.)

If someone in your family or social circle is an ongoing fount of conspiracy theories, it's worthwhile to counter their stories with the truth — which will often be at your fingertips.

"Just check on our cellphone the story the other guy just told us," Orosz said.

"We can use these rational strategies in everyday situations, say, 'These are the facts, my friend.' "

The theorist may or may not prove willing to accept reality, but either way, others who are listening will be able to hear evidence against a conspiracy.

It makes sense to inoculate yourself against conspiracy theories, as well, and people who exercise the logical parts of their brains seem to have some immunity.

In one University of Westminster study, people who were primed to think analytically by playing a sentence-unscrambling game were less likely to endorse conspiracy theories afterward. You can also give yourself an up-close look at how the sausage is made.

Kreko has given some of his students a unique assignment: Take two completely unconnected events (9/11 and North Korea's nuclear bomb testing, for instance) and invent a plausible connection between them — which, as the Internet shows, is exactly what real conspiracy theorists do.

"Think about any tragic events in the past 100 years," Kreko said.

"Google this tragedy and 'Jews,' and you will find something."

His students find the theory-generating exercise surprisingly easy, and he hopes it makes them wary of future supposed conspiracies they catch wind of. While it may be hard to remember in the heat of a debunking session, many conspiracy theorists' motives are noble, even if their yarn-spinning is not.

"People who believe conspiracy theories are deeply concerned about the future of society," van Prooijen said.

"Why would we [try to] make sense of events we don't care about?"

Still, Uscinski doesn't foresee much true evolution for the hardest-core believers.

"They're living in a different world," he said, "and it's very tough to bring them back."

2018 © The Washington Post

This article was originally published by The Washington Post.

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