How could praising a child for something as valuable as intelligence be bad? By making children think that their achievement was a result of something they are, rather than something they did. Repeatedly, studies going as far back as the 1980s have shown that when children are praised for intelligence instead of effort, they do worse on academic tasks.

More recently, a 2006 study published in the journal Social Cognitive and Affective Neuroscience bore this out. Jennifer A. Mangels and her research team recruited undergraduate students and determined which of two schools of thought they each fell into by asking questions about intelligence such as "You have a certain amount of intelligence and you can't do much to change it." Those who agreed with statements like that one aligned with what's known as the "entity" or "fixed" perspective, or the idea that intelligence can't be changed. Those who disagreed aligned with the "incremental" or "growth" view, or the perspective that intelligence can be improved.

With that established, the students sat at a computer and answered questions on a variety of academic subjects. They also indicated how confident they were in their answers. After every answer, the computer told them whether they were right or wrong, and what the correct answer was. Then they took the test again, but this time only faced the questions they had gotten wrong the first time. All the while, researchers measured their brain activity.

The results? Both the "fixed" and "growth" belief groups did equally well and were equally confident on the first test, but on the second test, the "growth" students were more likely to get the previously incorrect questions correct. Measures of brain activity showed that these students' brains seemed to show deeper attention when their wrong answer was corrected, suggesting that they were learning better than the "fixed" students. This says big things about the power of perspective: If you believe that intelligence is changeable, you actually learn better.

If you believe intelligence is fixed, you may be thinking, "Beliefs are one thing. What's the value in believing something if it isn't true?" Sorry, folks: The science is on the side of malleable intelligence.

Even IQ, that cold, hard, trusty number, changes throughout your life. Research shows that children with autism who get early interventions can experience large IQ gains, that more years of schooling equates to greater IQ, and that some training programs can even improve IQ in a matter of months. There's also plenty of research showing that the environment you're raised in has a big impact on your smarts — something that wouldn't be true if your intelligence were fixed at birth.

So what's a supportive parent to do? According to Parenting Science, the first step is convincing yourself. If you believe intelligence is fixed, you'll probably pass that on to your kids. Encourage children to exercise their mind like a muscle, and then praise them for their persistence, effort, and hard work rather than just being smart.

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Read about this principle from the researcher who pioneered it in "Mindset: The New Psychology of Success" by Carol Dweck. The audiobook is free with an Audible trial. We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.