What can you do to make yourself happier? If you’re like most people, the idea of increasing your own happiness probably appeals to you. But here’s a second question: Do you think it’s possible? Or do you believe some people are just born with a happy outlook on life, while other, less lucky, people are not? Your answer to that last question could make a very big difference.

That’s the fascinating finding of a new study of more than 7,000 people by researchers at Seoul National University in South Korea. Researchers measured how much participants believed happiness was something you were born with on a scale of 1 to 7. Subjects at the low end of the scale believed happiness was completely changeable. Those at the high end believed it was completely innate. On average, subjects fell slightly under 3 on that scale, meaning they were slightly more likely to believe happiness levels could change.

Then the researchers tested participants’ response to changing circumstances by asking them questions about hypothetical events, as well as real events such as the pandemic. As you might expect, those who believed happiness was inborn did not expect events to change their mood very much. Those who believed happiness was changeable expected to be more affected, negatively or positively, by events. And, they found, those who believed happiness was predetermined were less happy overall. Happiness may be a self-fulfilling prophecy.

They also found that, as with many things, beliefs about happiness could turn into a self-fulfilling prophecy. Those who believed happiness was preordained found it harder to improve their own emotional state. Those who believed that happiness was changeable were better able to change their own happiness level.

The truth is that both viewpoints are partly right. Research shows that happiness is 50 percent determined by genetics, 10 percent a result of circumstances, and 40 percent a result of what you choose to do. In other words, if you believe that happiness is entirely changeable, or entirely predetermined, you’re half right and half wrong.

But consider this: If you choose to believe your own happiness is at least partly in your control, you stand a good chance of having that belief come true. It’s another example of the difference between an internal and external locus of control. The more we believe in our power to change our own circumstances, the more likely it is we will actually be able to change them. Should you question your own beliefs?

So, let’s go back to the questions at the beginning of this column: Do you think that some people are innately happier than others? Or do you think you may be able to make yourself happier? If your answer to that second question is no, you might want to try and change that thinking.

In a piece for Psychology Today, Susan Krauss Whitbourne, Ph.D., professor emerita of psychological and brain sciences at the University of Massachusetts Amherst suggests gently questioning your own fatalistic, and self-fulfilling beliefs. Were you raised by people who took a negative view of the world? Did they discourage your attempts to take control of your own fate? Did you somehow get the idea that it would bring bad luck to try?

And, most importantly, what might happen if you start to believe that happiness might be something you can control? Or, if you just suspend your disbelief for a little while and try doing some of the things that could make you happy, and see if they work? You have nothing to lose by trying. And just maybe, some happiness to gain.