The Great Mental Models, Volume 1: General Thinking Concepts

by Shane Parrish

When understanding is separated from reality, we lose our powers to make better decisions. Understanding must constantly be tested against reality and updated accordingly. This isn’t a box we can tick, a task with a definite beginning and end, but rather a continuous process.

Understanding where you have an edge in competence and where you don’t helps you prevent problems, spot opportunities, and learn. We all have a circle of competence—an area in which we have a lot of knowledge. The size of that circle is not as important as knowing when you are approaching its perimeter.

Its always valuable to be reminded that you can quite easily get to that perimeter even in topics you are an "expert" in

As you cross the perimeter, not only does your advantage vanish, it goes negative.

There are approximately two hundred bodies on Mount Everest (to say nothing of the ones that have been removed). None of those people thought Everest would take their life. The climate preserves their corpses, almost as a warning. The ascent to the summit takes you past the bodies of people who once shared your dreams.

One of the essential requirements of a circle of competence is that you can never take it for granted. The terrain is always shifting. You can’t operate as if a circle of competence is a static thing that, once attained, is attained for life. The world is dynamic. Knowledge gets updated, and so too must your circle.

In a true science, as opposed to a pseudoscience, the following statement can be easily made: “If x happened, it would show demonstrably that theory y is not true.” We can then design an experiment—a physical one, or sometimes a thought experiment—to figure out if x actually does happen. Falsification is the opposite of verification: you must try to show that the theory is incorrect and, if you fail to do so, you actually strengthen it. To

That’s why we need Hanlon’s razor as an important remedy. Failing to prioritize stupidity over malice causes things like paranoia. Always assuming malice puts you at the center of everyone else’s world. This is an incredibly self-centered and impractical approach to life. In reality, for every act of malice, there is almost certainly far more ignorance, stupidity, and laziness at work.

Speaking personally, laziness knows no bounds.