Most of us wish we were smarter. But the best way to get smarter is to be willing to admit your ignorance and your mistakes and learn from them. In short, if you want to be more intelligent, being more open-minded is a good place to start. 

Super successful people know this already. Jeff Bezos has observed that the smartest people are constantly revising their opinions and are open to new points of view, ideas, and information that challenge their beliefs. Science agrees with the Amazon boss. The more willing you are to admit you're wrong, the faster you learn and the better decisions you make

Spotting true intelligence, then, is largely a matter of spotting those with a truly open mind. How do you do it? 

"I could be wrong but..."

On LinkedIn, self-made billionaire and hedge fund manager Ray Dalio offered no less than seven surefire tells that someone is open-minded. Many of them, like humility and responding to disagreement with interest rather than anger, are useful, if not incredibly specific or surprising. But one is both super actionable and surprising. 

This red flag that someone isn't open-minded is something you likely hear in conversation on a daily basis and may have thought was a positive sign about a person's intellect. 

"Closed-minded people say things like, 'I could be wrong but... here's my opinion,'" asserts Dalio. "This is a classic cue I hear all the time. It's often a perfunctory gesture that allows people to hold their own opinion while convincing themselves that they are being open-minded." 

"I could be wrong but..." sounds like open-mindedness, but if a person were truly more interested in gaining knowledge than in maintaining their own opinion, they wouldn't bother to say it. Instead, they would launch right into questions about the viewpoint or evidence that disagrees with them.  

"If your statement starts with 'I could be wrong,'" insists Dalio, "you should probably follow it with a question and not an assertion."

"The ability to change your mind is a superpower."

This red flag of a less than open mind is a great way to spot whether a potential hire (or date) isn't as intellectually humble as they think they are. But it's also a great yardstick to measure your own openness to new and challenging ideas. I confess that I sometimes say, "I could be wrong but..." and have given myself credit in the past for signaling I'm willing to consider new information. 

But after reflecting on Dalio's words, I can see that most of the times I use this phrase, I'm actually utterly convinced of my own rightness and just looking to appear polite to my conversation partner. I'd be better served to skip the empty pleasantry and actually dig into the reasoning of a person who disagrees with me (There are lots of great tips on how to have a constructive conversation with those with opposing opinions out there.) 

It's a little painful to admit that I might not always be as open-minded as I hope to be, but the payoff of seeing where I'm falling short and correcting my behavior (like all other forms of intellectual humility) is worth the momentary discomfort. 

As Farnam Street blogger Shane Parrish puts it in his thoughtful deep dive into Dalio's book Principles, "nobody wants to admit to themselves that they're closed-minded. But the advantages of having that courage are massive. The ability to change your mind is a superpower."