In yesterday's WSJ, David Aaronovitch wrote on the critical elements that nearly all conspiracy theories share (sub req):
It doesn't always feel like that. Many of us, of course, are not believers but simply find ourselves confronted at a dinner party by the man who just knows the "real story," and has arrived armed with his killer facts and certainty. You on the other hand, have nothing but your instinct for nonsense. So, for everyone who has been, or will be, in that woeful position, I offer this short guide to how conspiracy theories work, the better to rebut them.
Even where conspiracy theories are not momentous, and may sometimes be physically (if not intellectually) harmless--such as with the gorgeous slew of nonsenses that prefaced "The Da Vinci Code," involving Templars, secret priories, hidden treasures and the bloodline of Christ--they share certain features that make them work.
These include an appeal to precedent, self-heroization, contempt for the benighted masses, a claim to be only asking "disturbing questions," invariably exaggerating the status and expertise of supporters, the use of apparently scholarly ways of laying out arguments (or "death by footnote"), the appropriation of imagined Secret Service jargon, circularity in logic, hydra-headedness in growing new arguments as soon as old ones are chopped off, and, finally, the exciting suggestion of persecution. These characteristics help them to convince intelligent people of deeply unintelligent things.
All of us who have been in the position that Aaronovitch describe appreciate his insights on what really lies behind conspiracy theories. His forthcoming book from which the WSJ piece was adapted-"Voodoo Histories: the Role of the Conspiracy Theory in Shaping Modern History"--will no doubt contain even more useful information to help augment our instincts for nonsense.