Crystallized Intelligence (A complete guide)

Crystallized intelligence refers to the skills, facts and knowledge that we acquire throughout the course of our lives.

As we get older, we store and gather new information. As we go through this process, our crystallized intelligence gets stronger.  


Psychology experts have formulated many theories about intelligence over the past several decades.

Many of these ideas are based on how there are different types of intelligence.

Some people might have high intelligence levels across all types, some may have low intelligence across all types and others might have a mixture of high in some areas and lower in other areas of intelligence.

The two most common types of intelligence that we know are fluid intelligence and crystallized intelligence. 

In order to understand crystallized and fluid intelligence, we need to examine them both in a little more depth.

In this article, we’ll look at both crystallized and fluid intelligence to see what characteristics make up each kind and what it means to use them both in practice. 

Fluid Intelligence

Fluid intelligence is largely based on the ability to problem solve and use facts to answer a variety of problems.

Fluid intelligence is not applicable to one particular situation.

Fluid intelligence is at its strongest when someone is in their younger years and after that fluid intelligence often begins to decline.

You might notice that you have more trouble solving problems and working through abstract scenarios as you get older.

You will likely find yourself faced with intellectual difficulties that never crossed your path when you were younger.

Just because fluid intelligence starts to decline as you get older, it doesn’t mean that you can’t do anything to slow the decline.

Later on, we’ll discuss some strategies to ensure that your fluid intelligence is as strong as possible throughout your entire life.  

Crystallized Intelligence

If fluid intelligence is based in problem solving and application of facts in a variety of situations, then what is crystallized intelligence?

Crystallized intelligence often deals with your level of education and subsequent acquired knowledge.

Anything that you learn in a classroom setting is arguably a piece of crystallized intelligence.

Your skills from reading comprehension to foreign language to test taking helps contribute to your crystallized intelligence.

This information helps you complete tasks and have a deeper understanding of things that make up your world. 

Crystallized and Fluid Intelligence Together

While we experience crystallized and fluid intelligence at distinct periods in our lives, they peak at different times.

Fluid intelligence peaks when someone reaches the age of thirty or forty whereas crystallized intelligence is observed to peak between ages 60 and 70.

Formal education in any setting is one of the best observed ways to increase your crystallized intelligence over time.

The more information that you can take in and understand, the higher your level of crystallized intelligence.

To the surprise of some researchers, fluid intelligence is often manipulated with certain memory and intelligence exercises.

Short term memory exercises may help you retain a higher amount of information when you’re working on a particular task.

Studies showed that working on remembering concepts and ideas improved a person’s ability to reason through difficulties and solve problems.

Testing Fluid and Crystallized Intelligence

The WAIS and WISC are the most commonly used measures of intelligence among psychologists when looking at fluid and crystallized intelligence in large populations.

In large populations, professionals can test how test takers perform in different parts of the world.

What’s often seen is a younger person will perform better on a fluid intelligence test compared to someone who is middle aged, but the converse is true for people who take a crystallized intelligence test.

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Crystallized intelligence development

Crystallized intelligence is gradually developed through learning, studying new things, understanding, and achieving a wide variety of tasks.

Thus, we can measure crystallized intelligence by vocabulary knowledge, a person’s usage of sentence structure, reading comprehension and through other more formal measures like exams. 

There are two sets of influences that will have an impact on the growth of your crystallized intelligence.

External factors:

These factors include the culture, people and environments that you grew up with as a young person.

You will likely learn a lot from people who are in different stages, professions and locations.

Each of these experiences and interactions will help you develop your crystallized intelligence as you get older. 

Internal factors:

These factors comprise individual features like interest and internal motivation to learn new skills.

Some people are more driven to learn new things than others, and some people are more motivated to excel at work or in school than others.

These factors largely rely on who we are as people and what our genetic makeup is composed of at the cellular level.

Examples of crystallized intelligence

Below, we will take a look at some examples of crystallized intelligence in practice.

Our crystallized intelligence will develop over time and grow as we move through our past experiences.

We’ll use our crystallized intelligence to help us solve problems, play different types of games and participate in competitions.

Some examples of crystallized intelligence are noted below:

  • Knowing the precise dates of important historical events
  • Knowing every step and ingredient in a recipe by heart
  • Learning a new language
  • Remembering new mathematical and statistical formulas
  • Recalling statistics that you have read in the pas

Improving crystallized and fluid intelligence

Crystallized intelligence is obviously something that can be enhanced with the help of learning.

The more gathered information you have, the more crystallized intelligence you will possess.

So, if you are looking to improve your levels of crystallized intelligence, continuing your education is something that will help you significantly throughout this process. 

Until recently, fluid intelligence was something that was supposed to be set in stone.

However, new research has shown that training your brain may show enhanced features of fluid intelligence as you get older.

Research on intelligence proposed that people did not have too much control over their intellect at all.

Our IQ was supposedly determined by how intelligent our ancestors were. However, we’ve recently come to see that this is not the case. 

Education has long been seen as the way in which we should strengthen our crystallized intelligence.

Education does not necessarily mean classroom learning – this type of education can also take place outside of a classroom and can often be gained through work experience.

Taking in new, accurate information can lead to amplified levels of crystallized intelligence in our brains.

To the surprise of some researchers, we can also work on crystallized intelligence by completing memory exercises.

This helps both our working memory and our long term memory as we move through life.

Individuals who worked on improving their memory skills are able to better reason through problems and resolve conflicts. 

Measuring Crystallized Intelligence

Crystallized intelligence is measured by tests that look at language skills, reading comprehension and mathematical problem solving skills.

IQ tests may reflect different aspects of crystallized and fluid intelligence, but are predominantly focused on crystallized intelligence. 

Examples of Fluid Intelligence 

To comprehend the idea of fluid intelligence, it might be useful to look at some examples.

Below you’ll find a list of techniques and activities that individuals who have high levels of fluid intelligence engage in on a regular basis. 

  • Recognizing designs 
  • Solving puzzles
  • Using critical thinking skills
  • Sifting through large data sets
  • Avoiding getting stuck in a thought or belief and being open to new ideas 

Unmistakably, there is a distinction between these two types of intelligence.

The two work together in comprising an entire person’s intellectual capabilities.

For example, when someone takes their driving test, they might be able to remember certain facts such as what crosswalk signs mean (crystallized intelligence).

They might also identify some of the best ways in which to finish the test by piecing together what they should do in a particular driving scenario (fluid intelligence). 

Examples of Crystallized Intelligence 

One approach to consider when looking at crystallized intelligence is that it’s helpful for learning particular facts in a trivia contest or on a game show.

In the event that someone can learn and retain a large amount of information, they’ll likely excel on a game show like Jeopardy, as they are bound to have the ability to answer several trivia questions.

Some examples of crystallized intelligence would be: 

  • Knowing the MVP of Super Bowl III (Joe Namath) 
  • The temperature at which a steak is considered well done (166 degrees Fahrenheit) 
  • The dates of the Battle of Gettysburg (July 1-3, 1863)

FAQs on Crystallized Intelligence:

  1. How can I measure my own levels of crystallized intelligence?
    1. There are several ways you can look at your own levels of crystallized intelligence. One of these ways is to take a knowledge based quiz, play trivia or test how much you know about a particular historical event. It’s likely that you will remember a lot more than you think you do, especially as you get older.
  2. Is crystallized intelligence more important than fluid intelligence?
    1. Both types of intelligence are very important to the human mind and everyday life. Crystallized intelligence and fluid intelligence will be useful to you, but likely in different situations. Cultivating these skills is extremely important in ensuring your mind stays as strong and agile as possible. 

Interested in Learning More? Check out these books on crystallized intelligence:


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  2. Barbey AK. Network Neuroscience Theory of Human Intelligence. Trends Cogn Sci (Regul Ed). 2018;22(1):8-20. doi:10.1016/j.tics.2017.10.001
  3. Brown RE. Hebb and Cattell: The Genesis of the Theory of Fluid and Crystallized Intelligence. Front Hum Neurosci. 2016;10:606. doi:10.3389/fnhum.2016.00606
  4. Hartshorne JK, Germine LT. When does cognitive functioning peak? The asynchronous rise and fall of different cognitive abilities across the life span. Psychol Sci. 2015;26(4):433-43. doi:10.1177/0956797614567339
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