Smart people aren't just defined by their outrageously high scores on IQ tests.
They tend to share a bunch of other characteristics, like insatiable curiosity and a good sense of humor.
We took a look at a Quora thread where users have listed some common traits of highly intelligent people, and checked out the science to see if it backs them up.
Here are 11 qualities of super smart people:
They're highly adaptable

Several Quora users noted that intelligent people are flexible and able to thrive in different settings. As Donna F. Hammett writes, intelligent people adapt by "showing what can be done regardless of the complications or restrictions placed upon them."
Psychological research supports this idea. Intelligence depends on being able to change your own behaviors in order to cope more effectively with your environment, or make changes to the environment you're in.
They understand how much they don't know

The smartest folks are able to admit when they aren't familiar with a particular concept. As Jim Winer writes, intelligent people "are not afraid to say: 'I don't know.' If they don't know it, they can learn it."
Winer's observation is backed up by a classic study by Justin Kruger and David Dunning, which found that the less intelligent you are, the more you overestimate your cognitive abilities.
In one experiment, for example, students who'd scored in the lowest quartile on a test adapted from the LSAT overestimated the number of questions they'd gotten right by nearly 50%. Meanwhile, those who'd scored in the top quartile slightly underestimated how many questions they'd gotten right.
They have insatiable curiosity

Albert Einstein reportedly said, "I have no special talents, I am only passionately curious."
Or as Keyzurbur Alas puts it, "intelligent people let themselves become fascinated by things others take for granted."