What is First Principals Thinking?
This is not one of my typical informational posts. This is more of a personal experience that I’m relating back to skills and knowledge I use in my professional life.
Aristotle defined a first principal as “the first basis from which a thing is known.”
I’ve been hearing more and more smart people mention “First Principals Thinking” as a mental model they value. Well-known leaders look for it in the people they hire, innovators rely on it for solving the world’s hardest problems, and simple people like myself use it to figure out things we know nothing about. My wife loves to challenge every commonly “known” assumption for the sake of starting fun and less-stressful conversations — even though they tend to stress me out a little bit.
Fundamentally, first principles thinking is a method of problem-solving that involves breaking down complex problems into their most basic elements or truths, and then reasoning up from there. It’s about questioning every assumption you think you know about a given problem, then creating new solutions from scratch. This approach is often used to unlock creative solutions to complicated problems [source].
Here are some resources that delve deeper into first principles thinking:
- First Principles: The Building Blocks of True Knowledge – Farnam Street
- First Principles: Elon Musk on the Power of Thinking for Yourself – James Clear
- Elon Musks’ “3-Step” First Principles Thinking: How to Think and Solve Difficult Problems Like a Genius – Medium
- First Principles Thinking: Concepts & Examples – Data Analytics
- First Principles Thinking: How to Think Like the World’s Best Leaders
My Experience
I have a habit of wanting to learn how to do things I don’t currently know how to do. Sometime between childhood and adolescence, we realize that some things are harder to do (or do well) than others. I learned the hard way that I didn’t actually know how to do a backflip on the ground, and that I couldn’t just turn on a keyboard and play a song that sounded great. Experiences like these helped me start to form a mental model and approach for these things.
What do I want to do? > Why do I want to do it? > What will I do with the skill once I have acquired it? How important is it to me? > Is it worth the effort required to get there?
My first example of working through this process was learning to play drums. I determined that playing music was important enough to put in some effort. I eliminated other instruments because I didn’t feel like I had a strong enough preference to warrant the additional effort needed to understand notes, chords, melody, pitch, etc.
I started in middle school, which was much later than most of the other musicians I knew. Travis Barker, for example, started when he was 4 or 5. I recognized that I needed to learn some foundational skills to build on. Since this was before the dawn of Youtube, I sought out an instructor (actually several).
I had one teacher than insisted I needed to spend most of my time on basic stick work and rudiments to be truly good at drums. I had another teacher who immediately put me on a drum set, showed me a basic beat, picked up a guitar and started jamming with me.
At this point I realized that just because “an expert” says there is a specific way to do something, that it isn’t necessarily the best way. Learning to question people, books, and common knowledge, was the foundation of my adoption of this model.
Fast Forward to now
I’ve been using FPT to help me navigate my career, which has included several major shifts. I tend to be someone who is good at learning and who can metabolize information very quickly. When you pair that with my competitive nature and my ADHD, I tend to mold myself to be what I need to be in order to be very good at the thing I’m currently doing.
In the summer of 2022, my family moved from living in the small city of West Des Moines to a smaller ranch house on 56 acres of prairie and timber. Having mostly grown up in cities and town, I had almost no knowledge of what it means to tend for this amount of land. I had zero idea how to do most of the things I would need to do to maintain the land e.g. maintain the tractor, to operate a chainsaw to cut fallen trees, to manage bugs, to protect our animals from wildlife, and all the other things that ultimately ensure we could actually enjoy the land as much as possible.

First Principals and Mowers
I recently had a belt break on my mower deck for my tractor. I use the tractor mower to clear the trails so we can walk/traverse the property. If I don’t mow them, weeds like wild parsnip will overtake the trails. This plant specifically has a photoactive chemical that can cause your skin to burn and blister.
I was fortunate (or so I thought) that the previous owner had acquired an extra mower deck at an auction. I figured I would grab the belt from that one, place it on the current mower deck, and be good to go.
It’s never that easy.
If you want to really analyze the situation, you should think about how many assumptions I made:
- The belt was the only problem. (True)
- The mower decks were exactly the same. (They weren’t)
- The belt was in good shape. (It was)
- The second mower deck was in working condition. (Not really)
- Many others along the journey.
Why Starting without FPT is Silly
I tried to swap the belt out. I realized quickly that in order to do that I would need to dismount the mower deck and take a few pieces off. Over the next several weeks I found small pockets of time to try to accomplish what I assumed would be an easy task.
What I discovered:
The belt didn’t fit…
I measured the decks again… same size… slightly different shape.
I measured each wheel the belt wrapped around on both decks. Same size.
I measured the distance between the wheels. Same distance.
I tried to look up the difference between the models. One deck was a John Deere 62d2 and one was a 62d. Unfortunately, there isn’t a great resource out there with the information I needed so after a few hours of searching for the difference or the specific belt I needed, I stopped.
One day, after I cleared my head with a run, I walked over to my garage and put the two mower decks side by side. I realized that the piece that connects the deck to the PTO on the tractor was positioned slightly different between the two…
The wheel that was covered up was about an inch further from the center of the deck I was using than it was on the deck I was borrowing from.
To avoid a long boring story. A lot of time and stress could have been avoided had I actually been aware of the assumptions I was making and started from scratch at the moment I realized the belt didn’t fit. This would have opened many potential solutions up for testing much sooner and saved me hours mental and physical work.
I’m Humbeled

It’s humbling to catch myself going down a rabbit hole like this. I’ve coached many others on how to avoid this exact behavior in other scenarios. In work, it’s easy for me to identify situations that require a step back to FTP:
- I need to help someone with something I don’t understand very well.
- The person (or people) who needs help isn’t actually sure why there’s a problem.
- The person/people aren’t sure how to start approaching a problem.
- The problem space is stale.
- All of the ideas we are coming up with are based on what has already been done.
- The list goes on..
Moral of The Story
Questioning your assumptions is a fundamental skill for problem solvers. It’s ok to spend some time and energy exploring solutions that come naturally to you, but we all need to know when we’re forcing ourselves through a door that is simply too small. Often times the best answer is as simple as, “Use the bigger door.”
After about four weeks of dealing with this issue on and off, I finally got up and running. This was a process that identified many other issues and assumptions before putting time into trying to fix the problem. I spent more time starting at tractor pieces than I would like, but I spent less time taking things apart and putting them back together for no reason.