Intelligence has been a prized human trait for a long time. When we think of smart people, we know that they typically earn more money, attend school for longer, and have an easier time managing all of the troubles we face in life. They seem to have more common sense and see things that will happen over the long term. Maybe they’re even better at games like poker.

When you spend time with a highly intelligent person, it’s obvious that they are smart. They don’t need to tell you that they’re smart, show you proof of their achievements, or be arrogant. You just know. Their brilliance and common sense show themselves during routine conversations. They just seem more knowledgeable about everything than others.

There are common characteristics of highly intelligent people. If you’re spending time trying to hire the right person for an available job position and want to make sure to hire someone brilliant or simply want to surround yourself with smart people, you should look for these characteristics in the people you meet. If someone has a lot of these characteristics, they’re probably highly intelligent.

Here are 20 common characteristics to look for in highly intelligent people.

20. They’re Disorganized

It would be easy to assume that smart people are extremely organized. However, this is often not the case. Many highly intelligent people have messy desks, which some people would attribute to enhanced levels of creativity. Some of the most famous geniuses had extremely messy work areas, including Albert Einstein. Perhaps it is the continued need to problem solve to figure out where exactly the paper you need is located or the intense focus on other tasks over desk organization. Whatever it is, don’t make the wrong assumption that the smartest people are the most organized. This is simply not true.

19. They’re Adaptable

Highly intelligent people are easy to adapt to new conditions and environments. They excel in jobs even when the rules, tasks, and working environment change regularly. They are not the type of people that prefer repetitive tasks and can’t manage change. Highly intelligent people are much more likely to understand new restrictions and find ways to modify their environment. These individuals are flexible enough to go with the flow when plans change or are canceled last minute because they understand that in the long term, these small changes won’t matter. There will be other opportunities that they can create, if this doesn’t work out.

18. They Use Curse Words

While you shouldn’t assume that everyone who uses curse words is highly intelligent, researchers have found that those who frequently use swear words might just have a larger vocabulary than those who don’t. There is reason to believe that people who use curse words often are more confident with their vocabulary skills overall. This means that using these words isn’t a reliable away to make a judgement of someone’s intelligence. Keep in mind, however, that some very unintelligent people use curse words, too. With this characteristic, make sure that there are other traits found on this list to confirm intelligence with.

17. They Understand Limits

Highly intelligent people are the first ones to say “I don’t know.” Less intelligent people try to avoid the phrase because they feel that others will perceive them as dumb or ill-informed. Highly intelligent people understand that it is impossible to know everything about everything. It’s probably even unrealistic to know a whole lot about just a few things. These individuals understand that there’s a wealth of knowledge to everything and that they’d be lucky to simply understand some of it. When asked a question that they don’t know the answer to, they might say “I don’t know.” However, there’s also a good chance that they’d find out the answer if they needed to.

16. They Love Learning

Most people consider Apple’s famed co-founder Steve Jobs as highly intelligent, if not a whole host of other less favorable adjectives. After all, he was able to revolutionize the personal computing industry and helped bring the iPod into existence. Jobs notoriously loved learning, despite dropping out of college. He told junior employees that if they wanted to get ahead, it was important to continue learning outside of the classroom. Jobs and many other brilliant business leaders recognized that smart people love learning, even if it had nothing to do with credit and school. Highly intelligent people value that learning leads to new ideas and understandings about the world around them.

15. They Have A Sense of Humor

Smart people tend to have a better sense of humor than those with less intelligence, although sometimes their jokes aren’t as funny as they intend them to be for those with average intelligence. Because highly intelligent people are better able to understand things and perceive social situations, they can quickly come up with jokes in a timely manner. As a personality trait, being funny is linked to strong verbal communication skills. So for those that primarily rely on verbal communication and have developed these skills well, highly intelligent people will be able to make you laugh.

14. They’re Intuitive

Highly intelligent people have a greater sense of intuition than other people. This doesn’t mean that they have any psychic abilities (though perhaps some people coincidentally do). They are simply more in tune with the feelings and actions of the people around them. These people quickly recognize when someone needs a person to talk to or if their mood and attitude changes suddenly, such as after a phone call. This can make highly intelligent people excellent friends to have for support, listening, and providing great solutions for problems. Highly intelligent people will quickly notice changes in your attitude or overall demeanor even if they don’t say anything to you about it.

13. They Know There’s No Such Thing As Luck

Highly intelligent people don’t really believe in the whole concept of luck. Because they have a better understanding than most people of how the world works, they often believe that luck is a myth. Instead, good luck is likely the result of hard work, strategic planning, and coincidence, as well as staying prepared to accept great things that come their way. For instance, highly intelligent people who want to start a business go out to find new business deals. They do not wait for friends and family to refer them to help them out. In this way, they make their own good luck.

12. They’re Night Owls

People who stay up late and sleep in later are more likely to be highly intelligent than those who set regular sleeping hours. This is a statement that’s likely to be the mantra of every college students who wants just a little bit more sleep after a late night of partying. Researchers believe that those who wake up later are less likely to get tired as fast as someone who gets up super early with the help of an alarm clock. Maybe the lack of sleep exhaustion is part of the reason why those who stay up late tend to make more money, too.

11. They’re Abstinent As Teens

Okay, virgins are not more intelligent necessarily than those who partake in physical love. If they were, the smartest people in the world would be confined to monasteries and churches, where they practice abstinence. However, research shows that people who avoid sexual activity while teenagers are smarter. In some ways, this makes a lot of sense. If you learn all about gonorrhea and AIDS in sex ed and still go ahead with it, it probably signals that you don’t fully understand the consequences that you might experience as the result of sex. Not to mention, teen pregnancy can seriously stunt your future accomplishments and earning potential forever.

10. They’re Curious

Highly intelligent people are naturally curious. They want to know more about the world around them and continue to figure things out. This makes them smarter because of their increased knowledge about topics that interest them. If you meet someone who asks a lot of questions and seems genuinely interested in what you have to say, consider if they’re curious people. Highly intelligent people often want to know more and may ask questions, read books, go to museums, or speak with experts to attain that new level of understanding about whatever it is that they are currently very curious about.

9. They Have Self Control

Do you remember hearing about the experiment with self control in rats? When scientists offered a small treat to rats now or two treats to the rats if they could wait a little while, the scientists were testing the self control in the rats. In rats and humans, those individuals who can see the long term and wait for the better reward have more discipline and self control. This is a sign of a highly intelligent person (or rat) who can put aside immediate desires for the bigger picture. Unfortunately, most of the rats and humans couldn’t wait for the better payout.

8. They’re Risk Takers

When you think of risk takers, you think of Harry Houdini or dare devils such as Evil Knievel who take physical risks. You probably don’t think that these risk takers are so smart. However, highly intelligent people do take risks, they’re just well calculated risks. For example, imagine that two graphic designers work together for a company they both hate. The less intelligent one might just stay at her job and talk badly about how much she hates it. However, the highly intelligent one might create a plan to leave and start her own firm. Because she puts a lot of thought into it, it’s calculated and she just might succeed.

7. They Procrastinate

Highly intelligent people are also fairly prone to procrastination. Perhaps they love the thrill of finishing something last minute or are extremely confident in their ability to do so. They may also be more likely to put off tasks that they find boring until they can’t put them off any longer. Researchers think that procrastination could help lead to innovation and last minute thinking that’s not overthought. Instead of completing their work in advance, procrastinators just might be spending their time thinking of the next new innovation or idea. It’s important to note that not all procrastinators are highly intelligent. Some of them are just plain lazy.

6. They’re Not Overconfident

Smart people rate their intelligence lower than it really is, while less intelligent people rate their intelligence higher than what it is. It’s called the Dunning-Kruger effect. You’ve experienced it before when someone believes that they’re great at something that they’re really not even competent at. Like when an old person thinks they have amazing skills operating an iPhone, even when they don’t really know how to set the smartphone’s GPS system to navigate for them. Highly intelligent people recognize their own limitations and how much there is to learn. This makes them less likely to be overconfident in their interactions.

5. They’re Open-Minded

Highly intelligent people are more open-minded about people, new ideas, or differing ways of thinking. Because they value logic above traits such as untested loyalty, they’re much more likely to be open-minded. For instance, highly intelligent people are less likely to be close-minded about social issues such as race and sexual identity. They understand the biological components of these issues and are open-minded about the people who fall into these categories. Because they do not simply follow whatever they believe or have been told, they continue to stay more open-minded than their peers about people and new ideas. If you have a genuinely great idea, they’ll want to hear it even if it conflicts with their own.

4. They Have Good Instincts

Highly intelligent people rely on their instincts, knowledge, and education to make decisions. They are less likely than their average peers to make impulsive decisions because they are aware of their long term goals and what the impulsive decisions may damage in their plan. Highly intelligent people are usually working toward long term goals, whether getting additional education, saving money, paying off debt, or the next great business idea. As a result, they probably won’t get sidetracked by something that their instincts tell them is off. Fortunately, for highly intelligent people, their instincts are often correct and based on logic and facts.

3. They’re The Oldest Child

The oldest sibling likely has the highest intelligence than younger siblings do. This comes from many different factors. First, oldest siblings have the most one on one time with their parents because they existed before their siblings were born. From a biological perspective, the oldest and first child has the biggest responsibility of carrying down the genetic line. Second or third children don’t have this type of pressure from parents, so many of them prioritize their creative or favorite interests instead because it’s simply more fun. Also, other social factors within the family dynamic can influence this. For instance, older siblings are more likely to have experienced the responsibility of watching younger siblings.

2. They’re Introverted

Highly intelligent people don’t mind spending time with themselves. While not all highly intelligent people are introverts, their individualistic attitudes allow them to read, take a long walk alone, or dine by themselves without feeling self-conscious about being on their own. Many smart people also have hobbies that they love that they do alone. This can make them appear even more introverted and shy than they really are. Many people feel uncomfortable being by themselves and overschedule their calendars with activities to do with family and friends. Highly intelligent people are also less likely to do this just for the sake of having company.

1. They’re Non-Aggressive

Most highly intelligent people are not aggressive. They know that aggression can be a turn off and rarely allows them to accomplish their long term goals that they are passionately pursuing. In the face of an argument, many highly intelligent people will stand down in order to avoid arguing with irrational people they’d rather not waste their time. Also, if they do engage with you in an argument, they don’t want to be seen as emotional, weak, or illogical. This means that if they do have strong emotions because of the argument, they’re not likely to show it during the fight. They’ll wait later for the opportunity to rationally discuss it with someone.