If you’re feeling confident that you’re right in a disagreement, a new study might explain why you could actually be wrong. Researchers from Ohio State University found that people often believe they have all the information they need to make a decision, even when they don’t. They call this the “illusion of information adequacy.”

“We found that most people don’t stop to consider if there’s more information that could help them make a better decision,” the researchers explain. “If you give them a few pieces of information that seem to fit, most will say, ‘that sounds about right’ and move forward.”

The right information

The study involved 1,261 Americans who participated online. They were divided into three groups and asked to read about a fictional school that didn’t have enough water. One group read reasons why the school should merge with another that had adequate water, another group read only reasons to stay separate, and the third group read both sides.

The results were surprising. The two groups that only read half of the story—either just pro-merging or anti-merging arguments—still felt they had enough information to make a sound decision. Many were confident they would follow the article’s recommendation.

“People with only half the information were actually more confident in their decision than those who read the full story,” the authors explain. “They were sure their decision was correct, even though they didn’t have all the facts.”

Additionally, those with partial information thought most other people would make the same decision they did.

Changing minds

There was one positive finding: Some participants who read only one side later read the opposing arguments and many were willing to change their minds after getting the full story.

However, this openness may not apply to deeply ingrained beliefs, especially on ideological issues. In such cases, people might not trust new information or could reframe it to match their existing views.

“But most everyday conflicts aren’t about ideology,” the researchers point out. “They’re usually misunderstandings.”

This study adds to research on “naïve realism,” the idea that people believe their personal views reflect objective reality. While naïve realism focuses on how people can have different interpretations of the same situation, the illusion of information adequacy shows that people can share the same view—if they have enough information.

The researchers recommend that before making decisions, people should ensure they have the complete picture. “As we found, people tend to think they know all the facts, even when they don’t.”

When you disagree with someone, they suggest, ask yourself, “Is there something I’m missing that could help me understand their perspective better?” That’s how you can overcome the illusion of information adequacy.