Mental models: why you should use them.

By Abi Tyas Tunggal 20 June 2018 3 min read


  • A mental model is an explanation of your thought process regarding how something operates in the real world;
  • Adapting the way you see things is a powerful tool;
  • It's an excellent form of learning;
  • "If you can’t state arguments against what you believe better than your detractors, you don’t know enough."

Reading about Charlie Munger changed the way I thought about things.

Munger is Warren Buffett’s investment partner at Berkshire Hathaway. But that shouldn’t be his claim to fame. What he is world class at is finding and applying mental models.

A mental model is an explanation of someone's thought process about how something works in the real world.

Learning is hard. There’s so much out there and there’s little time to learn it. That’s why we need mental models. A mental model is nothing more than a way of looking at the world.

For example, when you talk to a physicist they see the world in a certain way.

They have a set of mental models that they learnt through experience. And that’s not unique to physics, every discipline has their own way of looking at the world. But don’t think that they don’t overlap.

According to Munger:

"80 or 90 important models will carry about 90% of the freight in making you a worldly-wise person."

That’s how you get smarter. You filter what you’re learning through your existing mental models. If it doesn’t fit, that’s okay. In fact, it’s better than okay. If you accept it, your thinking has improved. But if you don’t, you’re like everyone else.

In Munger’s words:

"Most people early achieve and later intensify a tendency to process new and disconfirming information so that any original conclusion remains intact."

The aim of learning is not to remember facts, life is not an exam. It’s to create a set of mental models and then test each model against something new. When something doesn’t fit, that’s when you should get excited.

As your set grows, you’ll get more interesting, more useful and wiser. Without mental models, you’ll never find your secret. Secrets only appear when many mental models melt into one conclusion. That’s where the value is.

But no one can explain mental models and their importance better than Munger himself:

"What are the models? Well, the first rule is that you’ve got to have multiple models because if you just have one or two that you’re using, the nature of human psychology is such that you’ll torture reality so that it fits your models, or at least you’ll think it does…

It’s like the old saying, “To the man with only a hammer, every problem looks like a nail.” And of course, that’s the way the chiropractor goes about practicing medicine. But that’s a perfectly disastrous way to think and a perfectly disastrous way to operate in the world. So you’ve got to have multiple models.

And the models have to come from multiple disciplines because all the wisdom of the world is not to be found in one little academic department. That’s why poetry professors, by and large, are so unwise in a worldly sense. They don’t have enough models in their heads. So you’ve got to have models across a fair array of disciplines.

You must have many mental models from many disciplines. Otherwise you only have one. That’s the core principle of mental models. Otherwise, you’ll be holding a hammer when you need a saw.

Hammers are irreplaceable when you’ve got nails. But that’s about it. The same is true of good ideas. A good idea in the wrong place is a bad idea. In fact, sometimes it might even be worse–because it’s harder to see the downside of a good idea."

Or as Abraham Lincoln put it:

"Give me six hours to chop down a tree and I will spend the first four sharpening the axe."

Mental models are your axe. If you were chopping down a tree, you’d make sure the axe was sharp. But most people look at what’s right about their models rather than what’s wrong. That’s the same as making sure the axe is dull before you start. It’s backwards.

Learning is a battle. A battle between your existing the new.

As Munger says:

“We all are learning, modifying, or destroying ideas all the time. Rapid destruction of your ideas when the time is right is one of the most valuable qualities you can acquire. You must force yourself to consider arguments on the other side. If you can’t state arguments against what you believe better than your detractors, you don’t know enough.”

Mental models: why you should use them.