From President Kennedy’s assassination to the Roswell UFO incident, history is teeming with events so calamitous or uncanny that the “true” explanation—whether it’s presented by scientists, historians, or the government—just doesn’t seem good enough. That’s where conspiracy theories come in.

But what exactly is a conspiracy theory, and why are people so inclined to believe them? In this episode of The List Show, Mental Floss editor-in-chief Erin McCarthy is delving into the psychology behind one of the most mysterious topics ever and shedding a little light on some popular conspiracy theories that did (or didn’t) turn out to be true. Did Lewis Carroll actually moonlight as Jack the Ripper? Also, what’s the deal with tinfoil hats?

Watch the episode below to find out the answers to those questions and more—and do it quickly, before the Illuminati deletes this video.

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