The Great Mental Models Summary

1-Sentence-Summary: The Great Mental Models will improve your decision-making process by sharing some unique but well-documented thinking models you can use to interact more efficiently with the world and other people.

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The Great Mental Models Summary

Your mental models are your best, or worst, toolkit you have on your hand when making decisions. These are the multitude of your thinking traits, the recollection of your past decisions and their outcomes, life lessons, and all the other circumstances that shaped the way you think today. 

Therefore, it’s particularly important to shape them right and give your mind the right thinking devices, so that whenever you’re faced with making a decision, you have mental options to choose from and create the best possible outcome. The Great Mental Models by Shane Parrish teaches you how to build up a series of thinking models that are great for helping you make the best decisions.

Here are my three favorite lessons from the book:

  1. Know what you’re good at and seek help when you encounter an area of weakness for you. 
  2. Look at the first principles of a problem and practice inversion to solve it.
  3. Play scenarios in your head before you try them in the real world and assess the long-term effects of your decisions.

Now, let’s take some time to explore each lesson in detail!

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Lesson 1: Knowing well your competences and your vulnerabilities is the key to success.

In life, there are certain things we excel at, and certain things that feel strange to us. It’s important to have a good grasp on both, Parrish suggests.

Our areas of competence feel natural and easy to explore. This is because, as we repeat a task, we become accustomed to it and our mind doesn’t need to actively engage in the process of doing it. Therefore, being aware of your circle of competence is essential for success. If you think about it, it’s simple – playing on your strong points will assure that you complete all tasks successfully, thus minimizing the chances of failure.

Moreover, being aware of your strengths and weaknesses will help you save time and be more productive. Let’s say you’re good with numbers and finance, so you’re able to file your taxes properly by the end of the year. However, you lack cooking skills, so it might be a good idea to shop for already cooked meals for the holidays. This way, you’ll save time and make sure that everything is completed successfully.

Although it may sound simple, you’d be surprised to find out how many of us let our egoes run get in the way of our decisions. Sometimes it’s hard to admit that we may not be good at something, especially if it’s a common skill between those around us. However, not knowing when to seek help is detrimental to our efficiency and can delay our success.

Lesson 2: Solve a problem by looking at its underlying cause and by practicing inversion.

Most people approach their problems wrong. Instead of curing the cause, they try to alleviate its symptoms. On top of that, you should be looking to prevent it from ever occurring again. So where to start? Essentially, you’ll want to look at the first principles of a problem, the ones that caused it in the first place. 

Think outside the box and find the root cause of the matter. When you find it, ask yourself if fixing it will prevent it from occurring again. That way, you’ll know if you truly fixed it, or it’s just a temporary fix. The second way to address a problem is through inversion, which implies turning the problem-solving process upside down.

You can do that in two ways. The first way would be to assume that something is true and then go backwards to look for what else needs to be true as well to fulfill your scenario. For example, let’s say you’re extremely wealthy. What else would need to be true for it to be the case? Things like not taking out expensive loans, spending less, saving more, are all good examples to be added on the list. Here is your solution!

Then, you can try to reverse this scenario a little to figure out your solutions. Assume you’re very poor. What else needs to fit in this scenario for it to be true? If you find that it takes spending too much, inflating your lifestyle whenever you have money, or not sticking to a budget, then these are the things you should avoid at all costs, and they’re the fix for your problem.

Lesson 3: Always think long-term before your take a decision and double-check it in your mind.

You might’ve heard people say “Think before you speak” – and for a reason! Thinking about what we are about to do instead of letting our impulses take over is a sign of maturity and good rationale. Thought experiments are key to successful endeavors because you get to train yourself for your real life encounters beforehand.

Moreover, if something goes wrong, you can replay that in your head and figure out alternatives for every potential thing that could go wrong. This low-risk high-reward mental model works best in life scenarios where you have to get it right the first time, like making a good impression, performing an extreme sport, presenting a speech in front of a large audience, or other similar situations.

Moreover, it’s important to assess the long-term consequences of your actions and balance them out with the short-term benefits. Sometimes it may be difficult to look at the bigger picture and acknowledge that in the long run, your actions can be more harmful than constructive, as the short-term benefits look tempting. 

This second-order thinking is helpful in situations that have a lasting impact on us. For example, if you indulge yourself to splurge and spend large amounts of cash on a regular basis, you may find yourself being broke, while all of your friends have already bought their first home. Think about the bigger picture and your future self whenever you make a decision. It’s helpful if you ask yourself “Is this helping me achieve my future goals?” Or “How will this affect me in time?”

The Great Mental Models Review

The Great Mental Models makes it easier for its readers to construct the right mental models which can help them navigate the world more easily. The book offers nine ways to use mental models as a way to fix various problems in your life. Its readers will learn a series of valuable lessons and psychological tips and tricks that will help them address issues from various perspectives.

Who would I recommend our The Great Mental Models summary to?

The 30-year-old entrepreneur who wants to improve their problem-solving skills, the 45-year-old psychology teacher who wants to spice up their curricula with alternative lessons, and anyone who wants to use mental models to give better advice to their clients.

Last Updated on May 19, 2023

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Maria Deac

While working with my friend Ovi's company SocialBee, I had the good fortune of Maria writing over 200 summaries for us over the course of 18 months. Maria is a professional SEO copywriter, content writer, and social media marketing specialist. When she's not writing or learning more about marketing, she loves to dance and travel all over the world.