The Boy Who Cried Wolf: Why Repeated Lies Can Hijack Our Beliefs (The Illusory Truth Effect)

Imagine this twist on the classic story of The Boy Who Cried Wolf: the boy lies so often about a wolf that, over time, the villagers start to believe him—even though they’ve never seen any evidence of one. Sound far-fetched? Not really. Science tells us that repetition alone can make falsehoods feel true. This psychological phenomenon, known as the illusory truth effect, highlights a vulnerability in how our brains process information—and it’s more relevant than ever in today’s digital world.

From political campaigns to social media algorithms, the illusory truth effect shapes what we believe, often without us realizing it. Here’s a look at the science behind it, why it matters, and how we can guard against falling for repeated misinformation.

The Science of Repetition: How Lies Become Believable

The illusory truth effect was first documented in a 1977 study by psychologists Lynn Hasher, David Goldstein, and Thomas Toppino. Their research revealed that people are more likely to believe a statement if they’ve encountered it multiple times, regardless of whether it’s true.

Why does this happen? It boils down to cognitive fluency, the ease with which our brains process information. Repeated statements become easier to process, and this familiarity tricks us into thinking they’re more credible. It’s an evolutionary shortcut—our brains equate ease with truth, saving time and mental effort.

This phenomenon also taps into our implicit memory, the unconscious storage of information. When we repeatedly hear something, it lodges in our memory as familiar. Over time, we might forget the context or source of the information but still feel like it’s “true.” This is why skepticism alone isn’t always enough to resist the pull of repetition.

Modern Examples: Repetition in the Digital Age

The illusory truth effect is amplified in today’s digital landscape. Social media platforms, powered by algorithms that prioritize popular or engaging content, are perfect breeding grounds for repeated falsehoods. For example, during the 2024 U.S. presidential election, unsubstantiated claims about voting machines “flipping” votes were echoed thousands of times across posts, videos, and news articles. Even when these claims were debunked, the repetition left a lasting impression on public opinion.

It’s not just politics. Advertisers use repetition to make brands feel familiar and trustworthy, while conspiracy theories gain traction by continually surfacing in online communities. A study by Lisa Fazio and colleagues in Psychological Science found that even when misinformation is labeled false on social media, repeated exposure still increases belief in it. The more you see it, the more credible it feels.

Breaking the Cycle: How to Resist the Illusory Truth Effect

Awareness is the first line of defense. Recognizing that repeated exposure can sway your beliefs helps you approach familiar claims with healthy skepticism. Here are practical strategies to guard against this effect:

• Pause Before Believing: When encountering a familiar statement, question its source and whether you’ve verified its accuracy.
• Seek Diverse Sources: Check the claim across multiple reputable outlets to ensure it holds up under scrutiny.
• Be Mindful of Social Media: Algorithms show what’s popular, not necessarily what’s true. Repeated exposure in your feed doesn’t mean something is credible.
• Challenge Assumptions: Just because a statement feels true doesn’t mean it is. Stay open to changing your mind when presented with evidence.

Why This Matters

The illusory truth effect isn’t just an academic curiosity—it has real-world consequences. From swaying elections to entrenching harmful myths, repetition can shape public opinion in profound ways. Understanding this effect empowers us to make more informed decisions and resist the pull of misinformation.

So the next time you hear the same claim over and over, think of the villagers and the boy who cried wolf. Repetition doesn’t make a wolf appear, but it might convince everyone there’s one lurking nearby.