It has been accepted in the scientific community that climate change is a result of human activity for almost twenty years. However, a study in 2016 found that less than half of U.S. adults believed that global climate change is due to human activity. In 2012, Trump tweeted that “The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive”. In a world with overwhelming evidence to the contrary, how can people continue to believe that global warming doesn’t exist?
Once people believe an argument, it is very hard to persuade them otherwise, even if they are told that the information they based their opinion on is incorrect. In a study conducted at Stanford University, two groups of students were given information about a firefighter named Frank. One group were told that Frank was a good firefighter; the other that Frank was a poor firefighter. Participants were then told that the information they’d been given was fake. Afterwards, they were asked to give their own opinion on how Frank would respond to a high-risk situation. Those who had initially been told that Frank was a good firefighter thought that he would stay away from risks, but those who had been told that he was a poor firefighter thought that he would take risks. This study shows that, even though they were then told it was fabricated, the initial information influenced participants’ opinions.
Confirmation bias is when people are more likely to believe facts which support an opinion they already had, rather than evidence to the contrary. A study in Stanford in 1979 involved two groups of students. One group was for capital punishment, the other against. Both groups were shown two fabricated articles. One contained data that supported capital punishment, the other data that opposed it (the statistics were designed to be equally strong in each article). Both groups stated that the source which supported their argument was more reliable. Furthermore, when asked to express their opinions on capital punishment after the study, both groups supported their standpoint even more than before. This demonstrates human nature to selectively believe what we want to be true.
It is believed that humans act this way because it was beneficial in early hunter-gatherer societies. Confirmation bias not only encouraged humans in societies to collaborate, but it was also important for social status to be considered correct. One theory for why seemingly rational humans continue to think irrationally is that we get a rush of dopamine when we see evidence which validates our opinion.
However, early human societies were not teeming with “fake news” and fabricated studies as we are now. It is increasingly clear how having a public swayed by confirmation bias can be dangerous to modern society.
We live in an illusion, where we think we know more than we actually do. For instance, one study found that when people were told about the new (fictitious) discovery of a rock that glowed, if they were told that the scientists who discovered it did not know why it glowed, participants did not claim to know as much about the rock as those who were told that scientists understood how it works (even though the subjects were not given any information on why the rock glowed). This phenomenon of people thinking they understand more than they do is common, and has actually been advantageous in terms of scientific progress. As scientists, we do not need to understand every scientific discovery there has ever been – we rely on the knowledge of our ancestors and those around us.
Humans are programmed to be influenced by information which they are then told is fake, and to think of sources which support their pre-existing opinion as more reliable than those which question it. However, this can be dangerous in areas such as politics. For example, if people around an individual claim to know why Brexit would be economically beneficial to the country, then even when presented with evidence to the contrary the individual is less likely to believe it. Likewise, if a person believes that global warming is a conspiracy, they are more likely to believe Trump when he says it was created by the Chinese than ecologists who say we are pushing our planet to critical levels. In a world where we are bombarded with clickbait and fake news, it is more important than ever to think rationally and critically about every piece of information.