...people who suspect conspiracies aren't really sceptics. Like the rest of us, they're selective doubters. They favour a world view, which they uncritically defend. But their worldview isn't about God, values, freedom, or equality. It's about the omnipotence of elites.
Conspiracy chatter was once dismissed as mental illness. But the prevalence of such belief, documented in surveys, has forced scholars to take it more seriously. Conspiracy theory psychology is becoming an empirical field with a broader mission: to understand why so many people embrace this way of interpreting history. As you'd expect, distrust turns out to be an important factor. But it's not the kind of distrust that cultivates critical thinking.
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But the survey instrument that was used in the experiment to measure "trust" was more social than intellectual. It asked the students, in various ways, whether they believed that most human beings treat others generously, fairly and sincerely. It measured faith in people, not in propositions. "People low in trust of others are likely to believe that others are colluding against them," the authors proposed. This sort of distrust, in other words, favours a certain kind of belief. It makes you more susceptible, not less, to claims of conspiracy.
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The common thread between distrust and cynicism, as defined in these experiments, is a perception of bad character. More broadly, it's a tendency to focus on intention and agency, rather than randomness or causal complexity. In extreme form, it can become paranoia. In mild form, it's a common weakness known as the fundamental attribution error ascribing others' behaviour to personality traits and objectives, forgetting the importance of situational factors and chance. Suspicion, imagination, and fantasy are closely related.
The more you see the world this way - full of malice and planning instead of circumstance and coincidence - the more likely you are to accept conspiracy theories of all kinds. Once you buy into the first theory, with its premises of coordination, efficacy, and secrecy, the next seems that much more plausible.
http://www.newscientist.com/article/dn24626-inside-the-minds-of-the-jfk-conspiracy-theorists.html