London School of Economics US Centre’s daily blog on American Politics and Policy – “Many or even most conspiracy theories are demonstrably false. But some, like Watergate, are true. How can we determine which are which? Drawing on his own experiences with conspiracy theorists, Stephan Lewandowsky writes that conspiratorial thinking is not necessarily truth-seeking behavior, but can often be a near-self destructive form of skepticism. We can use this skepticism, along with conspiracists’ tendency towards pattern-seeking and self-sealing reasoning, to flush out which are false, and which might be true after all.

• This article is part of our series based on the new book, Conspiracy Theories and the People Who Believe Them edited by Joseph E. Uscinski.

9/11 was a false flag operation planned by the US government. That same government sold weapons to Iran in order to fund Central American terrorists, and also created AIDS to exterminate gay people, and the CIA organized a fake vaccination drive in Afghanistan to get Osama bin Laden’s family DNA.

There is no doubt that two of those conspiracies actually happened and were hushed up by the conspirators, whereas the other two are widely dismissed as fantastical conspiracy theories. This is the long-standing dilemma confronting philosophers: conspiracies do occur and they can seem quite outlandish and unexpected once publically revealed—who would have thought that Oliver North would sell arms to Iran from the basement of the White House and launder the money to supply arms to Nicaraguan rebels in contravention of explicit legal prohibitions. But by the same token, most conspiracy theories are bunkum—we can be quite certain that the US Government did not create AIDS or fly airliners into the Twin Towers.

What are the differences between conspiracy theories that are almost certainly false and the evidence for actual conspiracies? This is a non-trivial philosophical challenge, but it is an important one to sort out, given that the mere exposure to conspiracy theories can undermine people’s trust in government services and institutions. Conspiracy theories are not harmless fun, especially if they lead people to refuse life-saving vaccination or to fire an assault rifle in a pizza restaurant in Washington….”