Especially with the older generation. Anecdotally, I have seen my mother have very extreme opinions on things simply bc "she saw an article on facebook" and didn't fact check anything in the article. It was impossible for me to convince her that the article was wrong.
You didn't have to read more than the synopsis to see that the article was thoroughly refuted.
The study had roughly zero effect on the beliefs of the person who shared the article. In effect, they already believed something (hot dogs are going to kill their baby), they found an article that agrees with them, and there will be no changing minds thereafter.
I may just engage with a subset of people who are prone to be like that, but a large portion of my facebook feed is similar. They just believe there's some puppeteer pulling the strings on everything. We can cure cancer but 'they' don't want to. We can create infinite free solar energy but 'they' don't want us to have it. "They" orchestrated the entrance into wars, "they're" hiding aliens, etc. Some of it is cliche conspiracy theory, but some of it leans towards "we're in the matrix" level of conspiracy.
I come to HN to keep grounded. I love it here because of rational discussion & debate among people who seek factual truths.
There's something called the Backfire Effect, wherein presenting facts and evidence actually reinforces people's positions, and can make them believe even more strongly in the thing you're proving is incorrect.
[1] http://rationalwiki.org/wiki/Backfire_effect [2] https://youarenotsosmart.com/2011/06/10/the-backfire-effect/ [3] http://bigthink.com/think-tank/the-backfire-effect-why-facts...
I mean your example is pretty extreme, I'm not going to say that was rational. But in general the average person doesn't have enough scientific knowledge to dispute a scientific study. In fact it's actually quite easy to make a case for almost anything by cherry picking studies.
So people have to rely on taking the consensus of others in their social group, or authorities they trust. And it means they don't actually have an opinion themselves, so you can't argue against them. They are just trusting the opinions of someone else.
This actually isn't a bad heuristic in general, but can lead to crazy beliefs like that. I think we all do this to some degree. I believe in global warming, but I couldn't possibly dispute any arguments against it that you could give me. I'm not going to change my mind though.