From Alex Koppelman’s “Why the stories about Obama’s birth certificate will never die” (Salon: 5 December 2008):
But according to several experts in conspiracy theories, and in the psychology of people who believe in conspiracy theories, there’s little chance those people who think Obama is barred from the presidency will ever be convinced otherwise. “There’s no amount of evidence or data that will change somebody’s mind,” says Michael Shermer, who is the publisher of Skeptic magazine and a columnist for Scientific American, and who holds an undergraduate and a master’s degree in psychology. “The more data you present a person, the more they doubt it … Once you’re committed, especially behaviorally committed or financially committed, the more impossible it becomes to change your mind.”
Any inconvenient facts are irrelevant. People who believe in a conspiracy theory “develop a selective perception, their mind refuses to accept contrary evidence,” Chip Berlet, a senior analyst with Political Research Associates who studies such theories, says. “As soon as you criticize a conspiracy theory, you become part of the conspiracy.”
Evan Harrington, a social psychologist who is an associate professor at the Chicago School of Professional Psychology, agrees. “One of the tendencies of the conspiracy notion, the whole appeal, is that a lot of the information the believer has is secret or special,” Harrington says. “The real evidence is out there, [and] you can give them all this evidence, but they’ll have convenient ways to discredit [it].”
Whatever can’t be ignored can be twisted to fit into the narrative; every new disclosure of something that should, by rights, end the controversy only opens up new questions, identifies new plotters.