There are at least two distinct ways to think about intelligence. Some people believe that intelligence is a fixed characteristic, something you are born with, like your bone structure or hair color. Others believe that intelligence is more malleable and can be shaped throughout your life. Regardless of whether either of these is true, it seems that the belief itself can change our behavior.

A new study published in the Journal of Experimental Social Psychology found that believing that intelligence is fixed makes people more likely to overestimate their own intelligence and therefore less likely to develop their own intellectual capacity.

The study used a GRE-style test administered to participants, and it found that people who believe intelligence is fixed are more likely to spend time on easy test questions, but they avoided challenging ones. By contrast, people who have a growth mindset regarding intelligence—believing that intelligence can be developed and changed—are more likely to spend their time on the hardest questions. This develops their skills in answering the problems they find the most difficult.

This challenge-averse behavior causes people with fixed ideas of intelligence to overestimate their own smarts. Since they don’t spend time on the hard parts of a task, they tend to think they’re better at the task overall. People with malleable views about intelligence tended to spend more time on hard questions during the test given to them by researchers, and they were therefore more able to accurately assess their own abilities. This finding is similar to the Dunning-Kruger effect, which found that people who are relatively unskilled in a task fail to recognize their own ineptness and therefore overestimate their abilities.

The authors of this study also found that when people were primed with information that suggested intelligence is a fixed characteristic, more subjects behaved like those who fundamentally believe that intelligence is fixed, regardless of their original viewpoint.

The issue of overconfidence appears to be a secondary effect of a person’s thoughts on intelligence. When participants were instructed to focus on the easiest parts of a task, they also began to show the same thought patterns as people who fundamentally believe that intelligence is fixed and overestimated their abilities. Receiving the opposite instruction reversed this outcome. When participants were instructed to spend most of their time on the most challenging part of a task, their confidence fell, and they were better able to assess their own skill level accurately.

In the classroom and workplace, intellectual overconfidence is a problem because it prevents people from learning effectively and developing their abilities—in order to learn and grow, you need to first acknowledge gaps in your knowledge and skills that you lack. Limiting the problem of overconfidence could help everyone develop. But it’s probably best to address the underlying issue while people are young—students may learn more effectively if they are taught to have a growth mindset and abandon the idea that intelligence is fixed.

Teaching students to have a growth mindset could potentially have a significant impact on some of the most vulnerable student populations that have the hardest time staying in school but have the most to gain from a strong education. Completing additional years of education has been widely shown as the most reliable way to increase professional opportunities and financial security.

Journal of Experimental Social Psychology, 2016. DOI: 10.1016/j.jesp.2015.11.001 (About DOIs).