Whether we're talking about phantom gunmen along President Kennedy's motorcade route on Nov. 22, 1963, or rumors that the government secretly is manipulating the weather, conspiracy theories provide an alluring, almost addictive alternative explanation of the world around us. Why do so many of us find stories of cover-ups in high places so appealing?
Michael Shermer, a psychologist and Scientific American columnist who wrote the 1998 book "Why People Believe Weird Things: Pseudoscience, Superstition, and Other Confusions," believes the answer that our brains are hard-wired to see conspiracies. "We generate beliefs based on patterns we believe we see in the world," he says. But researchers have shown that people will look for patterns even when none exist as a way of having a sense of control in the world. Shermer believes this tendency is exacerbated by events such as the Kennedy assassination or the September 11 attacks. "There's a cognitive dissonance going on between the size of the event and the size of the cause. A big event should have a big cause. But that's not the way it usually works."
In reality, he says, elaborate conspiracies don't occur as often as conspiracy theorists assume, because history tells us that the more sprawling the plot, the more likely it is to go awry or be leaked by someone who can't keep his mouth shut. "Look at the Lincoln assassination conspiracy," Shermer says. "They did get Lincoln, but their grand scheme was to assassinate his entire cabinet. Instead, that plan fell completely apart" [source: Kiger].