Shortly before killing 50 people at two New Zealand mosques, the man arrested for the Christchurch massacre posted an online manifesto that alluded to the “Great Replacement” — a racist demographic theory that stokes fears of white people becoming, effectively, extinct. Within hours of the shootings, this act of terrorism inspired by a conspiracy theory had already gone on to birth conspiracy theories about itself. Conservative radio host Rush Limbaugh speculated that the shooter was a secret leftist hoping to use the attack to smear the reputation of the political right.

That a single tragedy could be so tangled in conspiracy mongering should be no surprise at this point. We’ve all watched conspiracies grow from myriad soils: the missing Malaysia Airlines jet, the political passions of George Soros, vaccines, climate change, even the football secrets of the New England Patriots. Conspiracy theories appear to have become a major part of how we, as a society, process the news. It might be harder to think of an emotionally tinged event that didn’t provoke a conspiracy theory than it is to rattle off a list of the ones that did.

The ubiquity — and risks — of all these conspiracies has caught the attention of scientists. For years, the potentially dangerous consequences of conspiracy led many researchers to approach belief in conspiracies as a pathology in need of a cure. But that train of thought tended to awkwardly clash against some of the facts. The more we learn about conspiracy beliefs, the more normal they look — and the more some scientists worry that trying to prevent them could present its own dangers.

The experts I spoke with all said that the internet had changed the way conspiracies spread, but conspiracies, both dangerous and petty, have always been with us. Nobody knows, really, how popular conspiracy beliefs used to be, because it wasn’t a thing surveys regularly tracked until recently, said Jan-Willem van Prooijen, a psychologist at VU Amsterdam. But he and Michael Wood, professor of psychology at the UK’s University of Winchester, both pointed to a study that suggests conspiracies have consistently peered out of the pages of American newspapers for at least a century.

Joseph Uscinski, a political scientist at the University of Miami, cataloged and coded more than 100,000 letters to the editor published in The New York Times and the Chicago Tribune, and found the number of letters alleging and discussing conspiracy theories to have been pretty consistent over the last 120 years. This study isn’t perfect — the newspapers are still gatekeepers to what conspiracies were deemed fit to publish — but because it encompasses two different papers over a wide swath of time and many editorial leadership changes, Uscinski told me that it’s reasonable to assume we’re looking at something that reflects what interests readers, more so than what interests editors.

That research is significant to understanding conspiracy belief as a societal norm. “There was some crazy stuff that they were more than happy to publish,” Uscinski said. “The CIA is creating lesbianism. We found alien planets. … Jimmy Carter is a communist agent. Secret baby farms where they’re growing organs for people. It all wound up in there.”

And, it turns out, most of us believe in some strange goings-on behind the curtains. More than half of Americans think there was more than one person involved in the assassination of John F. Kennedy, for example. A 2014 study found that more than half of Americans believe in at least one medical conspiracy — a list that includes things like doctors giving children vaccines they know to be dangerous or the idea that the Food and Drug Administration intentionally suppresses natural cancer cures because of pressure from the pharmaceutical industry. The more specific conspiracies you ask about in polls, the higher the percentage of Americans that believe in at least one, Uscinski said. He thinks it’s likely everyone has a pet conspiracy to call their own.

What’s more, conspiracy beliefs aren’t necessarily all that special, said Carrie Leonard, a postdoctoral fellow in psychology at the University of Lethbridge in Canada. Leonard studies broader categories of what are known as “erroneous beliefs” — paranormal experiences, gambling fallacies, that sort of thing. The more we learn about conspiracy beliefs, the more they seem to have in common with these other kinds of wrong ideas, she said. Feeling a lack of control over various aspects of life, a tendency toward paranoid thinking, failure to understand and use statistics and probabilistic reasoning — all those things correlate with belief in ghosts and slot-machine prowess as much as with belief in the Illuminati. In fact, Leonard said, if you believe in the paranormal, you’re more likely to believe in conspiracy theories, and vice versa. (A finding that is probably completely unsurprising to the editors of The Fortean Times.)

At the same time, though, conspiracy theories have a sociopolitical aspect that makes them stand out. Leonard, and other researchers, think of belief in conspiracy as an interaction between individual tendencies and social circumstances. So, for instance, if you’re part of a group that is marginalized by society or lacks power in important ways you’re more likely to believe in conspiracy theories. That means being a member of a racial minority is a predictor of conspiracy belief — and so is unemployment, low economic status, or even just being a member of a cultural group that’s looked down on by people in positions of power.

Likewise, consider who is accusing whom of engaging in conspiracy. Uscinski’s study of newspaper letters to the editor tracked the social status of the letter writers. Consistently, he found conspiracies were punching up. Not only did average people write more than 70 percent of the conspiracy letters — as opposed to elite members of society — the conspiracies alleged were usually aimed at people in positions of power. There’s also no evidence to suggest that conspiracy belief is a phenomenon of the far right or the far left, Uscinski said. Americans broadly believe in a “them” pulling the strings and manipulating the country.

And this is where conspiracy beliefs start to get tangled up with truth. Because history does contain real examples of conspiracy. Pizzagate was a dangerous lie that led an armed man to walk into a family restaurant, convinced he was there to rescue children from pedophilic members of the Democratic Party. But that incident also exists in the same universe as the Tuskegee experiments, redlining and the Iran-Contra Affair. “I have this conspiracy that Western governments are involved in an international spying ring,” Wood said. “Before about 2014 that would have made you a conspiracy theorist. Now we know it’s true.”

Summoning — and demonizing — the belief in conspiracies can also have political consequences. “During the Bush Administration, the left was going fucking bonkers … about 9/11 and Halliburton and Cheney and Blackwater and all this stuff,” Uscinski said. “As soon as Obama won they didn’t give a shit about any of that stuff anymore. They did not care. It was politically and socially inert.” In turn, conspiracy theories about Obama flourished on the right. Uscinski said he is frustrated by this tendency for partisans to build up massive conspiracy infrastructures when they are out of power, only to develop a sudden amnesia and deep concern about the conspiracy mongering behavior of the other side once power is restored. It’s a cycle, he said that threatened to make social science a tool of partisan slapfights more than a standard of truth. And in a 2017 paper, he argued that conspiracy beliefs could even be useful parts of the democratic process, calling them “tools for dissent used by the weak to balance against power.”

These issues add up to more scientists beginning to have questions about what the goals of conspiracy belief research should actually be. Do we want an entire field of study aimed at preventing conspiracy theories from forming and dispelling the ones that do?

“I don’t think so,” Wood said. “I’m sure some people would disagree with me on that. But the objective shouldn’t be nobody speculates about people in power abusing power. That’s a terrible outcome for the world.”

He’s right — some scientists do disagree. Leonard, for instance, acknowledged that the world is complex, but viewed conspiracy theories as largely negative — erroneous beliefs, like gambling fallacies, but with the power to disrupt whole societies rather than just one person’s bank account.

Of course, all this debate assumes eliminating conspiracy theories is even possible. Van Prooijen told me that he’s currently working on a line of research to see whether a false conspiracy belief can be corrected by giving the people who believe in it something they’ve lacked — power and control over their own lives. In laboratory experiments, this seems to work, he said. Empower people, give them a sense of control, operate with transparency, and conspiracy theories seem to become less appealing.

Trouble is, in the real world, who has the ability to offer that kind of empowerment?

That’s right. THEM.

“If a group of people strongly distrusts a government or group of leaders, anything they do will raise suspicion,” van Prooijen said. Whether they want to get rid of conspiracies or not, scientists (and global leaders) are kind of stuck. Conspiracy beliefs are the norm, and difficult to shake because the people with the most interest in shaking them are, usually, the very people the conspiracy is meant to fight. As van Prooijen put it: “It’s not an easy task.”