More important than learning what to think is learning how to think ( critical thinking). So in this article, we will examine one approach that’s been useful to us—that critical thinking is learning how to use mental models. Mental models are the frameworks that we use to simplify and understand the world. And building a robust toolbox of these is a great way to think more clearly and make better decisions.
At his trial, Socrates apparently uttered the famous words that “the unexamined life is not worth living”. It means that we should strive to understand ourselves in order to have a deep and meaningful life. This includes examining and being critical of our thinking.
And one way to get better at critical thinking is to build up a database of mental models.
Mental models help us by reducing complexity in the world. We can’t pay attention to everything, and models help show us what is important—they block out the noise and boost the signal. At Exploring Kodawari, we refer to them as mental frameworks, and you can view our growing list of them here.
But in order to improve our critical thinking, we must first understand how mental models work. So this article is a kind of “meta” mental framework explaining what models are and why we need so many of them.
Mental Models And How They Help With Critical Thinking
Mental models are representations of how human beings think. They can be loose concepts with a wide utility or very narrow concepts for specific applications. But in all cases, they help us understand the world by highlighting certain information within it.
Mental models also highlight the connections we see in the world. For all intents and purposes, the world is infinitely complex, and mental models allow us to let go of most of that complexity so that we can pay attention to the relevant bits.
Without mental models, we would be completely overwhelmed—we wouldn’t have a hierarchy of what to pay attention to. With them, though, we have a better chance at figuring out what’s important and how to act.
While each model by itself is biased, critical thinking is having multiple models that compete against each other. This helps us to cancel out that bias by seeing reality from as many perspectives as possible.
Heuristics
One way of understanding mental models is to understand heuristics. A heuristic is a fancy term for what is commonly called a rule of thumb. These are rules or models of reality that are easily learned and broadly accurate. By definition, they are not completely accurate and they do not work all of the time.
So heuristics are approximations of reality that allow us to be more efficient with our thinking. They lower our cognitive demand by blocking out the complexity of each individual situation and focusing on the broadly true pattern.
For a heuristic to be good, it either has to be true most of the time or has to have a bias in the direction of safety. For example, the rule of thumb to treat every gun as if it’s loaded might be literally false most of the time, but still pragmatically true enough to prevent horrible gun accidents.
And mental models are like heuristics in that they don’t have to be completely right—they just need utility. As British statistician George Box once said, “All models are wrong, some are useful.”
As long as we are aware that heuristics can bias our thinking, they are safe to use. And when we have to make fast decisions, they are really our only choice.
Compressing Reality
When an image or sound file is digitally compressed, information is strategically removed in order to create a smaller file. Due to redundant information and limitations in human perception, compressed files can be many times smaller while retaining almost the same fidelity.
And a good mental model is similar—it simplifies reality by removing unnecessary information and focusing on what is useful. This overlaps with the psychological concept of cognitive schema. Schemas are how our brains interpret and categorize information in the world. For example, a chair and a beanbag have little in common objectively, yet our brains see them both through the same schema of “something to sit on”.
Like heuristics, schemas/frameworks/models are about utility. Our brains did not evolve to objectively understand the world—to find the ultimate truth. Instead, they evolved to build models that are true enough. Like digital compression, successful cognitive models simplify reality by maintaining sufficient complexity—that is, they are true/accurate enough to remain useful.
As soon as they are not useful, we either have to use a different model or update our model to accommodate new information.
Your Toolbox For Critical Thinking
We’ve already said that because of bias, critical thinking requires you to have multiple models (or categories of models) that see reality from different perspectives. For example, a biologist might rely too heavily on evolutionary models (incentives, hierarchies, niches, etc) while an engineer might rely too heavily on systems thinking (feedback loops, emergence, critical mass, etc).
So having a toolbox of multiple models, including those outside your specialization, helps you find the right tool for the right job. Or at least, because different models highlight different patterns, you’ll find a model that best fits your goals.
Plus, having more schemas/models also means that you can learn and retain information more quickly. This is why I prefer the term framework. Like Charlie Munger says, frameworks give you a place to hang information:
“Well, the first rule is that you can’t really know anything if you just remember isolated facts and try and bang ’em back. If the facts don’t hang together on a latticework of theory, you don’t have them in a usable form. You’ve got to have models in your head. And you’ve got to array your experience—both vicarious and direct—on this latticework of models.”
Charlie Munger, A Lesson on Elementary Worldly Wisdom
Just like your skeleton gives your body a structure, mental frameworks structure your knowledge in an organized way. And the more frameworks you have, the more organized and useful your knowledge will be.
Making Them Personal
Just because you read about a mental model, it doesn’t make it “yours”. To really own a model, you have to integrate it into your mind through personal experience. Otherwise, the model is just a shell—a name without enough depth. But this changes once you make it personal.
Personal models become deeply rooted in your mind. It evolves from a name to a complex network of connections and examples.
For example, I use the mental framework of the modular mind almost every day. This model says that, even though we feel like a unified mind, we are actually comprised of multiple “modules” competing for our conscious attention. It has a long and complicated scientific history, but the main takeaway is simpler: you have subpersonalities inside your head and many of them are shortsighted and selfish.
So with this model, critical thinking is realizing that certain thoughts are not even your thinking at all. Yes, they come from your brain, but the modular mind reminds us that evolution makes us think things that we don’t have to believe.
But just understanding the psychology of it is not enough. You have to also sit down and notice this mental framework in your own life. You have to subjectively feel how your modules try to control you. And this is true of all models—if you don’t make them personal their utility will be mostly limited.
Categories of Mental Models
As a person just looking to think more critically, make better decisions, and generally improve themselves, I’ve found that broader categories of models are often more useful than specific ones. You can use specific frameworks, but sometimes the larger category gives you enough perspective.
So here are some broad categories of mental models and a short description of how that framework can be useful.
Evolutionary Framework
It’s easy for human beings to feel like they are somehow separate from nature. But the evolutionary framework reminds us that we are a product of nature—gradual change due to evolution by natural selection. And this applies not just to our bodies but also to parts of our psychology.
Psychological traits that occur universally across cultures are good candidates for being adaptations. Certain cultural practices work this way too—you can think of culture as “idea software” that evolved to run on the hardware of the brain. When we learn to view ourselves through the evolutionary lens, a lot of our behavior and motivation make way more sense.
This doesn’t mean that evolved behavior is good just because it’s natural (the naturalistic fallacy). Instead, it’s a way to understand ourselves so that we can be more consistently moral.
Hedonic adaptation, the modular mind, and consciousness are all mental models that fit into this category.
Logical Fallacies
Logical fallacies are the classic thinking traps that our brains can fall into. We are especially susceptible to these in arguments and debates. While fallacious arguments might appear legit and persuasive on the surface, they contain logical errors that invalidate whatever is being argued.
A logical fallacy may be committed on purpose (deceptive) or on accident (just sloppy thinking). But the point is that either way, an argument based on a logical fallacy is false—although a claim can still be true even if its reasoning is false.
So logical fallacies are great mental models to learn about and notice in your thinking. They highlight the common patterns of how we tend to be sloppy with our thinking, and being familiar with them will improve your critical thinking skills.
Some popular examples of logical fallacies are ad hominem, the slippery slope, and the straw man. Aim to learn them and notice them in yourself and others. This will definitely improve your critical thinking skills.
Physics
This category refers to general laws or concepts from physics that we can personify in our human lives. One example is inertia. Inertia states that an object will resist changes in velocity and direction unless acted on by an outside force. And this principle of motion also applies to individuals and organizations.
Relativity is another powerful physics concept that we can export into our thinking. You don’t have to understand Einstein to realize that our frame of reference biases us. For example, if we’re in a plane at cruising altitude, we don’t realize that we’re going nearly 600 mph. But an outside observer would notice this immediately. And this effect occurs in our social lives as well. Critical thinking requires that we be aware of how relativity biases us.
Engineering Frameworks
Engineering frameworks are similar to physics (because engineers rely on physics to build things). But they tend to involve concepts that reveal themselves in more complex systems.
For example, emergence says that sometimes lower-level parts create unexpected higher-level phenomena. And often we can’t even reduce that higher-level emergence to truths from the lower-level domain.
Another engineering principle is feedback loops (A causes B which loops back to A). A classic example of this is when you place a microphone next to its speaker, quickly resulting in a high pitch screech (positive feedback). Positive feedback loops run out of control whereas negative loops (like a thermostat) maintain equilibrium.
These types of frameworks apply not just to engineering systems but also to ourselves and the organizations we create.
Conclusion: Critical Thinking Is Critical
Critical thinking is not just knowing what to think but knowing how to think. It is understanding more consciously how the human mind learns and makes sense of the world. And because mental models are how we do this, learning them more consciously will allow you to think more clearly and make better decisions.
So if you want to get better at critical thinking, consider adding more and more mental models to your toolbox. Study them and make them personal. Over time, they will help you to live a more balanced and consistent life.
Mental Model Resources
- Farnam Street’s List of Mental Models
- James Clear’s List of Mental Models
- Farnam Street’s Shane Parrish on the Making Sense Podcast
- Exploring Kodawari’s Growing List of Mental Models
