What are the mental models?
Your life is isolated into two sections: before you grasp mental models and after.
Mental models are design patterns for thinking, and they simplify complicated things so your brain can reason through them. They help us find the signal in the noise. You use them to reach sound judgment without having to have a deep understanding of a circumstance.
“You get further in life by avoiding repeated stupidity than you do by striving for maximum intelligence.” — Charlie Munger
Why mental models?
Mental models do two jobs: they help you evaluate how systems work, and they help you make reliable decisions. These two concepts hold everything you do.
You have to learn all the big ideas in the key disciplines in a way that they’re in a mental latticework in your head and you automatically use them for the rest of your life. If you do that, I solemnly promise you that one day you’ll be walking down the street and you’ll look to your right and left and you’ll think "my heavenly days, I’m now one of the few competent people in my whole age cohort." If you don’t do it, many of the brightest of you will live in the middle ranks or in the shallows.
- Charlie Munger