By David Ludden, Professor of Psychology, Georgia Gwinnett College (Atlanta)

The Deep State is trying to destroy the presidency of Donald Trump. Vaccines cause autism, but drug companies don’t want you to know that. The moon landing was a hoax—it was actually filmed in a Hollywood studio. The 9/11 attack was orchestrated by the U.S. government.

You’ve probably heard all of these conspiracy theories before, and many more besides. And if you’re like most people, you probably wonder how anyone could believe such nonsense. Nevertheless, a sizable minority of the population buys into one or more conspiracy theories. Once little more than a fringe group, conspiracy theory believers have now found their voice with the advent of social media.

Because conspiracy theories sow the seeds of distrust in our governmental and social institutions, they can have a destabilizing impact on politics and society. Since we can’t just dismiss conspiracy theories as inconsequential, we need to understand the psychological factors that make them so appealing to so many people. This was the goal of New York University psychologist Jay Van Bavel and his colleagues, whose review article on the topic was recently published in the journal Current Opinion in Psychology.

The researchers start out by noting that conspiracy theories often constitute serious threats to democracy, in that they encourage social discord, disengagement from the normal political process, and sometimes even encourage violence. One such example would be conspiracy theories about Jewish global economic domination, which have circulated in Europe for centuries and formed the foundation for the Nazi movement in 1930s Germany. White supremacists in the United States still buy into this idea today, leading them to verbal attacks on prominent international Jewish figures such as George Soros. In short, conspiracy theories are dangerous and should not be lightly dismissed.

Before we can educate the public about how to decide whether a reported conspiracy is real or fake, we need to understand what draws people to conspiracy theories in the first place. Prior research has found that people are motivated to believe in conspiracy theories for three reasons. First, they make believers feel good about themselves and the groups they belong to. Second, they help believers find meaning in a confusing world. And third, they lead believers to feel safe and in control.

These observations are valid as far as they go, but Van Bavel and colleagues also maintain that not all conspiracy theory beliefs can be explained this way. The researchers note that some people bolster their social identity with the conspiracy theories they ascribe to, as in the case of neo-Nazis and belief in a Jewish conspiracy.

However, others are drawn to conspiracy theories as a way of asserting their own uniqueness in a “conformist” society. For instance, people who believe the Earth is flat or that the government is controlled by lizard people from outer space don’t derive any sort of social identity from their beliefs. Rather, they see themselves as special because they’re privy to knowledge that non-believers don’t have or are unwilling to accept.

To understand how these two motivations—social identity and uniqueness—work, Van Bavel and colleagues turned their attention next to the characteristics of conspiracy theories, specifically their content and their qualities. In this theory, the content consists of the unique narrative elements of the conspiracy theory—the government is run by lizard people, Jews are conspiring to dominate the world economy, scientists fabricate data on climate change to garner more research funds, and so on. The content is what differentiates one conspiracy theory from another.

However, the researchers also propose that all conspiracy theories have a set of qualities in common. These are the structural properties that make a particular belief a conspiracy theory. For instance, all conspiracy theories point to a specific group that is conspiring to deceive or do harm to society—the government, the Jews, pharmaceutical companies, lizard people, and so on. But conspiracy theories also point out a separate group of people—the believers—who know about the conspiracy and are actively trying to expose it.

Van Bavel and colleagues argue that the content and qualities of conspiracy theories provide separate motivations for believers. In particular, the content of specific conspiracy theories provides social identity motives for those believing in them. Neo-Nazis define themselves, at least in part, by their opposition to a supposed Jewish conspiracy. At the same time, they may dismiss out of hand other conspiracy theories, such as the flat Earth or the moon landing hoax, that are irrelevant to their social identity.

In contrast, those who seek to set themselves apart from “conformist” society are drawn by the uniqueness motives that the qualities of conspiracy theories provide. The actual content of these conspiracy theories is less important than is the “inside knowledge” that the believer has obtained. Thus, people with uniqueness motives will tend to believe in multiple, perhaps even contradictory, conspiracy theories—9/11 was an inside job, the moon landing was a hoax, lizard people from outer space control the government, and by the way, the Earth is actually flat.

In an age of social media, the internet, and twenty-four-hour entertainment masquerading as news, we face a constant onslaught of information, much of it false. So how do we tell whether a report of a conspiracy is likely to be true or not? After all, as the conspiracy theorists rightly point out, conspiracies actually do happen. Governments spy on their citizens, corporations knowingly sell dangerous products, and yes, sometimes scientists do fabricate data for personal gain.

Rather than relying on our intuitions, which can lead us as easily to cynical skepticism as to unfounded belief, we need to follow the founding principle of the scientific method, known as Occam’s razor. Specifically, when a particular phenomenon can be explained by two competing theories, we should assume that the simpler one is correct.

While conspiracies certainly do occur, it’s also a fact that humans are really bad at keeping secrets. True conspiracies get revealed sooner or later when one or more of the conspirators leaks information about it. This observation tells us that reports of conspiracies involving large numbers of people over long periods of time are very likely to be false.

In sum, the best way to discern whether that story you read on Facebook is true or not is to ask yourself if an alternative explanation is simpler. While this line of reasoning is unlikely to sway a true believer, it can help you keep your sanity in a crazy world.

David Ludden is Professor of Psychology at Georgia Gwinnett College in Atlanta