Mental Models: How to Remember the Things That Matter

One of the most common struggles people have with learning technology is feeling overwhelmed by the amount of information. What’s worse, this struggle often continues into job interviews (and jobs). I’m going to teach you how to solve this. 

This article shows you how to unlock your superpower and learn large amounts of technology more quickly and with less effort than you’d think. Let’s start with an exercise that teaches us about how memory works.

First, try to remember these number sequences.

The first sequence is 1 2 3 4 5 6 7 8 9.

The second is 6 2 8 3 1 8 5 3 0

The third is 0 7 7 0 6 5 0 8 4

And the last is 9 9 9 9 9 9 9 9 9

OK… Now, try to remember that 299 million, 792 thousand, 458 meters per second is the speed of light in a vacuum. And 340 meters per second is the speed of sound at sea level. And eleven meters per second is the flight speed of an unladen swallow. European, of course.

It’s OK if you can’t! The second part of this exercise only pushes the four nine-digit sequences out of your short-term working memory. Don’t scroll back – do you remember those four numbers now?

Chances are good that you still remember that the first number was 1 2 3 4 5 6 7 8 9. And you probably also remember that the last number was 9 9 9 9 9 9 9 9 9. Right? But you might have forgotten that the second number was 6 2 8 3 1 8 5 3 0 and the third was 0 7 7 0 5 6 0 8 4.

Why is that?

Well, it’s because your brain parsed, understood, and changed the first and last number sequences to their underlying principles when you saw them. Your brain did not remember the numbers, it remembered what it understood. For the first sequence, it remembered, “These are the digits from one to nine.” For the last one, it remembered, “That’s nine nines.”

But it couldn’t make immediate sense of the other two sequences. And actually, the third number is wrong the second time I printed it. The original sequence was 0 7 7 0 6 5 0 8 4. Not 5 6. Did you notice the switched digits?

It’s OK if you didn’t notice!—most people won’t. However, you would definitely have noticed if I had switched numbers in the first sequence. Your brain would have latched onto that error because you know how to count!

In case you’re curious, the second sequence is Tau—which is twice Pi—and the third one is the decimal ASCII numbers for M A T—the first three letters of my name. These are not quite as simple as “one-to-nine” or “nine nines,” but now that you know what the patterns are, you might be able to tell them back to me, even next week! Sure, you might need to translate what you do remember—meaning what you understand—into the actual number by looking up Tau, or Pi, or using an ASCII converter, but your brain now has something it can grab onto.

And that is key. Because in the real world, we don’t need to memorize numbers or other information. Rather, we need to understand the technology well enough to look up and double-check the details when they might matter.  And, to be clear, memorized numbers shouldn’t matter in any tech role interview, either—either the interviewer is trying to assess your on-the-job potential or that’s almost certainly not a job you’d want to take, anyway.  

So when people ask me, “How can I memorize all this?” I say, “You don’t.” You remember what you understand. So focus on that, instead.

And of course my reason for going through this exercise was to help you understand this point, not just hear me say it. And that means you’ll probably remember it, too. Let’s look at how this applies to your learning. It’s easy enough to say that you should understand things, but I want to help your brain do that by teaching you about mental models.

A mental model is a simplified representation of reality that your mind uses to anticipate events or draw conclusions. Basically, it's what your brain builds when you understand something by organizing new information into hierarchies. It includes recognizing patterns and is a kind of data compression for the brain. That’s what allows you to remember the two easy sequences from the first exercise – knowing how to count is a mental model, and being able to recognize repeating patterns is the basis for all mental models. 

When you use logic instead of memorization, that is based on a mental model. For example, you don't remember that 123456 is a larger number than 987, but you understand that it is. Here's a quote from Prof. David Skillicorn, of the School of Computing at Queen’s University: “Anyone can learn faster by structuring the information. This is another one of those common trade-offs—getting right into it can feel satisfying, but taking some time to organize can increase effectiveness, even if it doesn't feel so satisfying in the short term.”

What’s more, mental models don’t just make learning faster; they actually make learning easier, too! Like we’ve seen, our human brains are much better at remembering related concepts than unrelated details. And when we try to squeeze in too many details, we can often find ourselves pushing out other ones unintentionally.

But with a mental model, the more you build and refine it, the easier it becomes to learn more information. And not only do mental models help you learn faster and easier, but what you learn is far more valuable to you. So even though the better efficiency is great, the higher effectiveness of your learning is arguably the most important benefit!

The interesting problems in life are trade-offs, and you'll often be faced with situations where you won't know all the details involved. To be able to work effectively, you'll need to be able to 1) predict likely behaviors, 2) identify your assumptions, and then 3) validate your theories through investigation and testing. A strong mental model is the critical foundation you need for these steps (And if this looks like science, it’s because it is! My alma mater’s Computing Science program is in the faculty of Applied Sciences.)

What I mean is that whether you’re building them on purpose or subconsciously, mental models are a hard requirement for succeeding with technology. You can’t succeed without them.

To build a mental model, the key is to stop asking, "How will I remember this?" and start asking, "How does this information fit into or change my mental model?" There are two parts to that.

Some information will simply “fit into” the mental model we already have. The new information is similar to what we’ve seen before, so it strengthens our existing mental model. This type of information often feels calm, comforting, and confidence-inspiring.

But some other information won’t fit, because it somehow conflicts with the mental model we’ve built up to that point. This “conflicting” information may feel chaotic or confusing, but it is actually the most important type for learning.

This is where we need to do what learning scientists call “double-loop learning.” In this type of learning, instead of just using information to make new decisions, you use it to refine your mental model. Here’s an example from Chris Argyris’s book, Teaching Smart People How To Learn, that Wikipedia uses to explain double-loop learning: 

“[A] thermostat that automatically turns on the heat whenever the temperature in a room drops below 69°F is a good example of single-loop learning. A thermostat that could ask, "why am I set to 69°F?" and then explore whether or not some other temperature might more economically achieve the goal of heating the room would be engaged in double-loop learning.”

To learn more efficiently, we should learn both what something is and how to apply our understanding of it to real-world situations. That often means we should actively seek out the sorts of things that cause us to rethink our mental model. Even though it might not feel good to be confused, it’s kind of like building muscle strength: if we don’t feel any soreness, we’re probably not making much real progress. 

When we work through the confusion to reshape our mental model into something that is better at organizing all the information we’ve seen, then we convert more of the not-yet-seen information into the calm and comforting kind, too. This is like our mental model just leveled up—Ding!—and can handle future situations more easily with its improved strength.

Let’s say that you need to organize all your books onto shelves, and let’s say that you have a lot of books. You need to remember the location of each book, too. 

You start with a very simple system: Chaos. You just put books wherever they fit. But that doesn’t help you remember their location at all. So you decide to order them by the date you got them. That means you can skip around on your shelves based on what you remember about other books, too, but that’s still tough because you have too many. 

You try organizing by the date of publication. But that actually makes things worse. Instead of grouping book series together, they wind up scattered and interleaved across the whole set of bookcases. Next, you try the author’s first name, but some names are too popular. Last names are better, but you’re not always sure of the author’s name because it’s easier to remember the subject rather than the author. 

But then, you think back to your school days, and you remember the Dewey Decimal System for shelving, and the International Standard Book Numbering for cataloging. It clicks. The Dewey Decimal system allows you to categorize books by the subject matter, which is much easier to remember. Sure, you have to replace subjects with numbers, but once you understand how it works, it’s a much more intuitive system. Underneath the long string of numbers is a description that actually fits much better with your mental model of which books you own. 

This is your “Aha!” moment. Now, you see how powerful that approach is. From that point on, adding new books or finding them is a much simpler matter of determining the number and going to the specific shelf where that book should be. You will never again need to do a wholesale reorganization of all the books.

So, do you then know where every book is!  Yes!  But you haven’t memorized where every book is because that doesn’t really matter.

A very mature organization system is one that doesn't need to change much at all—and that’s what you want for your mental model, too, because it represents expertise.

When you start out learning something, every new piece of information is new and has a pretty high chance of conflicting with your mental model. That might feel a bit discouraging, but don’t let it get you down! As your mental model improves—as it matures—it will require fewer and fewer changes. 

You’ll find yourself assimilating new information much more quickly. Through organizing what you learn into your mental model, you’ll think, "Okay, this goes here, and that goes over there." That high-speed learning can feel really rewarding.

And, of course, that expertise has professional value, too!

An important takeaway from all this is that you have to be careful not to get lost in your learning. Progress is not measured by how much learning material you’ve consumed, but by how well your mental model supports information. So don't “keep powering” through what you're trying to learn if you don't really understand or aren't paying attention. If you're not constantly incorporating information into your mental model, then you're not learning effectively and you're not making any real progress. At best, you're just trying to memorize stuff. It’s kind of like throwing books toward a bookshelf from far away. It might seem like the books are closer to where they're supposed to go, but really, you've only made a big mess to clean up.

On the flip side, even little minutes can add up to BIG developments in your learning. So try to make learning a continuous habit. It may feel “slow and steady”, but that might just be what “wins the race”.

So, when it comes to remembering the things that matter, how mature your mental model is is the best way to measure your learning progress. Building that mental model is the slowest—and most important—part of your journey toward expertise.

If you found this article useful, I highly recommend checking out my article: How do I find time to study? 5 keys to successful learning.