Recently, researchers have asked more than 2,000 adult Americans and European adults for their ideas on genetically modified foods.
They also asked how much they thought they understood genetically modified foods, and a series of 15 really false questions that test how much they know about genetics and science in general.
Scientists have been interested in studying a perverted human phenomenon: People tend to be miserable judges about how much they know.
In four studies conducted in three countries – the US, France and Germany – the researchers found that extreme opponents of genetically modified foods know the least, but believe they know the most.
The authors point out another way: "The less people know, the more it is against scientific consensus."
"Scientific communicators have been focusing on educating the public with a view to bringing their views in line with experts," Nature Human Behavior writes.
People with an inflated sense of what they really know – and most need education – are the least likely to be open to new information.
"This suggests that the prerequisite for changing people's views through education can be to first appreciate the gaps in their knowledge," the authors write.
The problem is similar to the Dunning-Kruger effect: A less competent person is on the one thing the smarter they think they are.
"Not only do these people make erroneous conclusions and make unfortunate decisions," writes David Dunning and Justin Kruger in a 1999 article describing this phenomenon, "but their inability is depriving them of the metacognitive ability to realize them."
Or as the English actor and comedian John Cleese once said: "If you are very, very stupid, how do you realize you are very, very stupid? You have to be relatively intelligent to realize how stupid you are."
Extreme opinions often come up with a lack of appreciation of the complexity of the topic – "we do not know how much we should know," said Philip Fernbach, lead author of a new study and marketing professor at the University of Colorado Boulder. "People who do not know much think they know a lot, and that is the basis of their extreme views."
His team's findings were held across educational levels and for people on either side of the political alley.
Genetically modified foods are a non-binding issue, Fernbach said. "People on the right and left have some hateful function of GMOs," although most scientists consider them as safe for human consumption as conventionally grown.
"Genetic engineering is one of the most important technologies that dramatically changes the country and has a huge potential for human beings," said Fernbach. "And yet there is a very strong opposition."
In one of their studies, 91 percent of 1,000 adults surveyed by adult Americans reported some resistance to genetically modified foods.
Far more extreme, Fernbach and his co-authors found that fewer people knew about science and genetics, but the more their "self-assessment" of knowledge – how much they thought they knew – increased.
"If someone is well calibrated, these two things should be very correlated: If I know how much I know, then if I knew a little, I should say I know a little, and if I know a lot, I have to say I know a lot," he explained Fernbach. "Therefore, there should be a high correlation between self-assessment and objective knowledge.
"And it really applies to people who are mild or to people who have a stance that is in line with scientific consensus," he said.
However, as people become more extreme, this relationship worsens and deepens, so people who think they know more actually know less.
"Extremists have this feature that they are far worse than other people in evaluating how much they know," said Fernbach.
The authors, who included colleagues from the University of Toronto, also explored other issues such as gene therapy to repair genetic disorders and reject human-induced climate change. They have found the same effect on gene therapy, but not on denying climate change. Fernbach predicts that climate change has become so politically polarized that people report to whatever their ideological group says, no matter how much they think they know.
People often suffer from the "illusion of knowledge," writes the authors, "thinks he understands everything from ordinary household items to complex social policies better than they do."
"So the obvious thing we should try to do is educate people," Fernbach said. "But in general it was not very effective."
Sometimes it's getting worse and people are doubling their "contradictory attitudes," said Fernbach. "Especially when people feel threatened or treated like they are stupid."
He and his colleagues plan to look at how their findings deal with other issues, such as vaccinations and homeopathy, "to find out how predominant this misbehavior is."
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