Debora MacKenzie in New Scientist:
Heard the latest? The swine flu pandemic was a hoax: scientists, governments and the World Health Organization cooked it up in a vast conspiracy so that vaccine companies could make money.
Never mind that the flu fulfilled every scientific condition for a pandemic, that thousands died, or that declaring a pandemic didn't provide huge scope for profiteering. A group of obscure European politicians concocted this conspiracy theory, and it is now doing the rounds even in educated circles.
This depressing tale is the latest incarnation of denialism, the systematic rejection of a body of science in favour of make-believe. There's a lot of it about, attacking evolution, global warming, tobacco research, HIV, vaccines – and now, it seems, flu. But why does it happen? What motivates people to retreat from the real world into denial?
Here's a hypothesis: denial is largely a product of the way normal people think. Most denialists are simply ordinary people doing what they believe is right. If this seems discouraging, take heart. There are good reasons for thinking that denialism can be tackled by condemning it a little less and understanding it a little more.
Whatever they are denying, denial movements have much in common with one another, not least the use of similar tactics (see “How to be a denialist”). All set themselves up as courageous underdogs fighting a corrupt elite engaged in a conspiracy to suppress the truth or foist a malicious lie on ordinary people. This conspiracy is usually claimed to be promoting a sinister agenda: the nanny state, takeover of the world economy, government power over individuals, financial gain, atheism.
More here.