The answer is that 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…

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.

Once you buy into the first conspiracy theory, the next one seems that much more plausible.

A decade later, a study of British adults yielded similar results. Viren Swami of the University of Westminster, working with two colleagues, found that beliefs in a 9/11 conspiracy were associated with “political cynicism”. He and his collaborators concluded that “conspiracist ideas are predicted by an alienation from mainstream politics and a questioning of received truths”. But the cynicism scale used in the experiment, drawn from a 1975 survey instrument, featured propositions such as “Most politicians are really willing to be truthful to the voters”, and “Almost all politicians will sell out their ideals or break their promises if it will increase their power”. It didn’t measure general wariness. It measured negative beliefs about the establishment.