How can you tell if you're intelligent? More important, how can you get smarter? Jeff Bezos says the best indicator high intelligence is a willingness to change your mind.

Science says the most intelligent people love spending time alone. Other science says the smarter you are, the more likely you are to believe you can spot patterns and predict outcomes (though science also says you're wrong about that).

Unsurprisingly, Steve Jobs had a different take on intelligence:

A lot of it is memory. But a lot of it is the ability to zoom out.

Like you're in a city. And you could look at the whole thing from the 80th floor. And while other people are trying to figure out how to get from point A to point B reading these stupid little maps, you can just see it all in front of you. You can see the whole thing. You can make connections that seem obvious because you can see the whole thing.

To Jobs, intelligence was based on making connections. On connecting the dots.

Even though you will often only be able to connect those dots in hindsight.

There's Intelligence ... and then there's intelligence

While there are at least eight different forms of intelligence, let's focus on two.

Crystallized intelligence is accumulated knowledge. Facts. Figures. In simple terms, book smarts.

Of course, some highly "educated" people are not necessarily smart smart. That's where fluid intelligence comes into play: The ability to learn and retain new information and use it to solve a problem, or learn a new skill, or recall existing memories and modify them with new knowledge. In simple terms, street smart.

Plenty of people are book smart. Plenty of people are street smart. Those who are both are somewhat rarer, if only because the process of increasing crystallized intelligence tends to be fundamentally different from the process of increasing fluid intelligence.

If you want to become more educated on a particular subject or skill, the process is simple. The deeper you dive into that topic, the more you'll know. 

Improving fluid intelligence is harder, because it requires you to take a deep dive, and then move on to something new -- over and over again.

Why? Work to learn something new, and for a time your brain's cortical thickness and cortical activity increases. Both are signs of an increase in neural connections and learned expertise. Yet after those first few weeks, cortical thickness and activity actually starts to decrease, eventually returning to a baseline level. 

The result? You definitely know more, or can do more, but once you acquire that knowledge or skill -- once you've figured things out -- your brain doesn't have to work as hard. 

Add it all up, and the only way to improve your fluid intelligence, and keep it high, is to continue to experience new things. Learn new things. Try new things. Challenge yourself. 

At work. At home. Anywhere.

And then there's lasting intelligence.

Do that, and not only will you benefit from a constant flow of new information and skill, your brain will stay "thicker" and will keep forging new neural connections.

Which makes it easier to keep learning and getting smarter.

All of which brings us back to Steve Jobs:

If you're going to make connections which are innovative, to connect two experiences together, you have to not have the same bag of experiences as everyone else. Or else you'll make the same connections and you won't be innovative. So you have to get different experiences.

You can hear stories about all (highly intelligent) people, but the key thing that comes through is that they had a variety of experiences they could draw upon in order to solve a problem or attack a dilemma in a unique way. 

The more you know, and the broader your experiences, the more you can leverage the power of associative learning: The process of relating something new to something you already know by spotting the relationship between seemingly unrelated things. 

In simple terms, whenever you say, "I get it: This is like that," you're using associative learning. And whenever you think, "Wait I could apply this to that," you're using that learning to make smart connections.

Like how Steve Jobs used his experience auditing a calligraphy class in college as the inspiration for Apple's early typefaces. Or how Kevin Plank used his experience playing college football to develop Under Armour's moisture wicking garments.

Or how Sara Blakely built a company based on nothing but an idea and a willingness to learn everything else: Write patent applications. Develop prototypes. Design packaging. Find suppliers. Persuade retailers to take a chance on her.

Each experience resulted in experiences she could and then draw upon to find new ways to keep solving problems.

The more you learn, the more likely you will be able to associate "old" knowledge to new things. Which means you have only to learn differences or nuances. And you'll be able to apply greater context, which also helps with memory storage and retrieval, to the new information you learn.

And to the new experiences you acquire.

All of which makes learning even easier, which research shows will result in your being able to learn even more quickly -- and retain a lot more.

Which will make you even more intelligent than you already are.

Science, and Steve Jobs, says so.