Why do otherwise rational, sensible people choose to reject good science in some cases and believe unfounded claims in others?

With apparently eroding trust in government and authority, people are looking to less reliable sources of information – which is particularly dangerous when it comes to health. On the one hand, they believe stories such as ‘Facebook causes cancer‘, or in the unproven alt-meds of homeopathy and vitamin supplements, yet they reject solid scientific evidence with regard to vaccine safety, anti-retroviral drugs or GM crops.

As Michael Specter says in this TED 2010 talk, “We hate BigPharma… and we run from it into the arms of Big Placebo*.”

“The idea that we should not allow science to do its job because we are afraid is really very deadening, and it’s preventing millions of people from prospering.”

From a TOK perspective, how does this talk highlight the clash between emotion and reason in the ways of knowing? (Or as Specter says, “You have the right to your own beliefs- but not your own facts.”)

*The industry in non-proven remedies and vitamin supplements runs to billions of dollars a year.