First principles thinking is one of the most effective mental tools you can have in your toolbox. It also explains why some people are far more innovative than others.

Here’s what it is, why it matters, and three lessons.


Think of first principles as individual LEGO pieces. While they come in different shapes and colors, two things are important. First, they can’t be reduced further. Second, They can be combined in new and interesting ways to create something new.

Imagine we’re trying to build a house at work.

You show up to a meeting and someone shows you something that sort of resembles a house.

You move a few of the LEGO blocks around and get to a better solution. The solution is incrementally better than what you started with.

Approaching the same problem by thinking in first principles allows you to take the LEGO structure apart, inventory the pieces, and see all the ways they could combine to create something new and better.

Here you create something significantly better than the original.

First principles thinking is breaking things down into the core parts and reassemble them in a more effective way. This is why people call it thinking like a scientist or even just thinking for yourself.

Here are three lessons you can take away and use today:

Lesson One: Beware of what you inherit. When someone presents something to you the tendency is to make it slightly better rather than ask if it's right in the first place.

--> When it comes to decision making, this means never letting anyone else define the problem for you.

--> When it comes to the workplace this means not accepting the analogies, frames, or existing solutions.

Lesson Two: The best way to break out of a rut is to go backwards not forward. Break things down into the parts to see what you’re dealing with. It’s harder but you’ll be surprised by what’s suddenly possible.

Lesson Three: If you’re stuck, ask yourself what is 100% true? It's a quick way to break through existing structures, frames, and analogies.

The Great Mental Models Volume 1: General Thinking Concepts offers more ways to use first principles thinking.

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You can follow @ShaneAParrish.


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