First Principles Thinking

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What’s the difference between an innovative, breakthrough start-up, and just another average company with some tech? Simple. The way they think.

First Principles Thinking is originally accredited to late philosopher Aristotle who said, “the first basis from which a thing is known.” Aristotle’s approach to each and every concept in life was to gain knowledge through experience and use reason to give structure to understanding something¹. For Aristotle, you achieved mastery in a subject only if you could break the subject down into its first principles. 

The First Principles of a subject are the things we know, without a doubt, to be absolutely true. The main advocate of this model of thinking in today’s world is CEO & Founder of Tesla, SpaceX, and The Boring Company, Elon Musk.

When Musk first decided to launch SpaceX in the early 2000s, one of the biggest needs was being able to buy a rocket. On a flight home from being rejected to purchase a rocket from the Russians, Musk decided he could just build his own.²

Since no one would sell Musk a rocket, he did some research and took rocket launching down to the first principles. He looked into the physics behind a rocket launch and what rockets were made out of. Then, he calculated the cost of the raw materials needed to build a rocket and hired engineers and scientists to build it. Instead of buying the typical on-board computer that’s priced at $1,000,000, his team used the type of computer inside of an ATM and built it for $5,000. NASA’s rocket launches of the past typically cost $430 million. SpaceX’s cost is around $133 million.

By asking, “What do we know is absolutely true about rocket launches?”, Musk and his team were able to cut all the excess baggage and make an affordable, safe, and smart rocket for more than one-third of the original cost to buy a rocket.


  1. Innovation - Once you can identify and understand the most basic fundamentals of a process or an idea, you can rearrange those to create a new product or idea.
  2. Optimization - By understanding each component individually, you can ensure each component is optimized to be operating at its highest efficiency
  3. Integration - Understanding of the most basic principles allows you to integrate the idea or system into new ideas or systems, or integrate other ideas or systems into this one.
  4. Teaching - Knowing the fundamentals of an idea makes it much easier to teach someone about the idea.


A simple and effective way to start thinking in first principles is to create hierarchies or mind maps for each area of knowledge or product. Then, go down the list from the highest view, to the most basic, and ensure understanding and mastery of each category and sub-category.

Let’s say a school year is composed of 250 days at school.

A day at school is composed of 6-7 different classes.

Each class is composed of ~ 35 students, one teacher, and ~16 new topics.

Each new topic is composed of one essay, two quizzes, one presentation, and two chapters in a text book.

Each essay is composed of 3-5 thoughts or ideas about one topic, which are tested on using the quiz, and reinforced using the presentation.

To ensure someone has a great year and learns a lot, each idea that is a subcategory of a new topic must be taught well and mastered by each student.

How do students master ideas and topics?

Through active recall and spaced repetition.

How do we ensure a student learns a lot and has a good school year?

By practicing active recall and spaced repetition for each individual idea and topic taught in each class.

That’s a school year broken down to its First Principles. If you haven’t noticed, teaching methods haven’t changed in the slightest bit over the past 15 - 20 years. It’s just the same old thing over and over again. By breaking school down to its first principles, we can see that active recall and spaced repetition are needed to master and learn topics. By breaking it down to its first principles, we get down to the change that needs to happen; how we’re going to build a new school-like rocket. When we do that, we come to the conclusion that If it’s unlikely to be able to practice active recall with each topic, maybe someone should start writing new curriculum.

The way things have been done, does not mean that’s how they should be done. Break things down into its first principles and start innovating old ideas in new ways.

Written by
Dalton Mabery