Why people insist they’re correct without all the facts

Sometimes, it's easier to say ‘that sounds about right.’
an illustration of one woman yelling and another holding her hands up in shock
People tend to assume that they have all of the information that they need to make a decision or support their position–even if they don’t

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Getting into arguments with strangers online or family members at the dinner table can feel a bit like debating with a brick wall. We are probably all guilty of feeling like we are right, even if we don’t have all the facts. According to a recent psychology study, people tend to assume that they have all of the information that they need to make a decision or support their position–even if they don’t. This phenomenon dubbed the “illusion of information adequacy” is detailed in a study published October 9 in the journal PLoS ONE.

“Interpersonal conflict is on the rise, driving increases in anger, anxiety, and general stress,” Angus Fletcher, a study co-author and narrative theorist and neurophysiologist at the Ohio State University, tells Popular Science. “We wanted to look into those misunderstandings and see if they could be mitigated.”

Reading arguments

In the study, the team from Ohio State, Stanford University, and Johns Hopkins University surveyed 1,261 Americans online. All of the participants read an article about a fictional school that did not have adequate water. 

Group one read an article that only gave reasons why the school should merge with another that has better water. Group two read an article that only gave reasons for the schools staying separate and hoping for other solutions to the problem. Group three was the control group that read all of the arguments for the schools merging and staying separate. 

[Related: The biggest consumers of fake news may benefit from this one tech intervention.]

They found that the majority of the two groups who only read the pro-merging or anti-merging arguments still believed that they had enough information to make a good decision about what to do. Most said that they would follow the recommendations in the article they read. 

Those who read the “pro-merge” article were significantly more likely to recommend that the schools merge, while the “pro-separation” participants were significantly more likely to recommend that the schools remain separate. About 55 percent of the control group recommended the schools merge.

The participants who had half the information also said that they thought most other people would make the same decision they did. 

The illusion of adequacy

The team calls this belief that we are correct–even when we don’t have all of the information–the illusion of adequacy.

Fletcher describes the illusion of adequacy as, “The less that our brain knows, the more confident it is that it knows all it needs to know. This makes us prone to thinking that we have all the crucial facts about a decision, leaping to confident conclusions and decisive judgments, when we are missing necessary information.”

[Related: The real reason people share so much fake news on social media.]

These findings also offer a complement to a field of research on naïve realism. This is the belief that an individual’s subjective understanding of a situation is the objective truth. Studies on naïve realism usually focus on how people can have a different understanding of the same situation. However, the illusion of information adequacy shows that people may share the same understanding, if they both have enough information. 

Changing minds?

The team found that some of those participants were willing to change their minds about their decision–once they had all the facts. The mix of opinions after hearing both sides was comparable to the control group–about 55 percent to 45 percent. 

“If you give people a few pieces of information that seems to line up, most will say ‘that sounds about right’ and go with that,” says Fletcher

Timing also plays a role. The main caveat is that the people in the study changed their minds about opinions that were recently formed. These were not ideas that had become deeply entrenched. For example, a second study conducted by this research group that centered on the death penalty was abandoned.

According to Fletcher, one of the best ways to fight the illusion of information adequacy when disagreeing with someone is to stop and ask, “Is there something that I’m missing that would help me see their perspective and understand their position better?”

“This can help eliminate unnecessary interpersonal conflict, allowing us to focus our energy on working through substantive differences between ourselves and others,” says Fletcher.

 

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