How To Think From First Principles – Like Elon Musk

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"The first basis of which a thing is known" - Aristotle

How To Think From First Principles - Like Elon Musk - Sketch of Space X Rocket Ship

First principles thinking allows you to think clearly and think for yourself. By definition, a first principle is a basic thought that cannot be reduced further. You can learn how to incorporate this into your thinking tool kit and I will show you three ways to start. In my (current) opinion, on the journey to "think better, do better, be better" understanding reasoning from first principles is step number one.

It centers around the deconstruction of your current ideas and assumptions. You're always starting from some previous conclusion because you've got some previous learning or bias you're working away from. The status quo is built on these assumptions and just because that is how it currently is doesn't mean that is how it has to be or even how it actually is in reality. A lot of the time thinking from first principles is thinking differently because most people start by reasoning from analogy and what they already believe to be true. Analogical reasoning comes from your observation that things which are similar in some ways are probably similar in other ways.

Enter Steve Jobs: "Here's to the crazy ones, the misfits, the rebels, the troublemakers, the round pegs in the square holes ... the ones who see things differently -- they're not fond of rules, and they have no respect for the status quo. ... You can quote them, disagree with them, glorify or vilify them, but the only thing you can't do is ignore them because they change things. ... They push the human race forward, and while some may see them as the crazy ones, we see genius, because the people who are crazy enough to think that they can change the world, are the ones who do."

He understood that by challenging the current thinking and reducing it down as far as possible he could drive innovation at Apple. The idea of 1000 songs in your pocket seemed impossible in the age of CDs but not if you think different. The reason thinking in this way could seem rebellious is because we humans are social creatures that seem to require consensus on important issues. As soon as someone starts to challenge another person's beliefs about a concept there can be what looks like an immune response to the person doing the challenging. Changing beliefs can be hard.

Kids are good at thinking from first principles at first because that's all they know. Everything is new. Why is it like this? But why? Why why why. Challenging all assumptions. Once we think we know what we know we don't challenge our thoughts as much. Challenging thoughts takes energy, it's like going to the gym for the mind. As more happens in the world it's very easy to move away from the first principles and it gets harder to think for yourself. We're memetic creatures after all and are very good at copying each other. Fitting in can feel more important than having your own thoughts. This can lead to dogma: "a principle or set of principles laid down by an authority as incontrovertibly true." Challenge dogma.

Even though we have a propensity to copy, there are people who have chosen to think different. Aristotle is credited with being one of the first documented thinkers using reasoning by first principles. Two other thinkers that I admire, Shane Parish and James Clear, have both written about this topic and I encourage you to read their posts as well. People have written about first principles thinking for a long time and it was recently popularized by Elon Musk with his discussion on how physics teaches you to approach a problem. He's quoted as saying, "I think it’s important to reason from first principles rather than by analogy. The normal way we conduct our lives is we reason by analogy. [With analogy] we are doing this because it’s like something else that was done, or it is like what other people are doing. [With first principles] you boil things down to the most fundamental truths…and then reason up from there.” How do these people reason from first principles? Good question and I can't know for sure because I'm not in their minds but I've got some ideas for you.

1. Challenge Your Assumptions

Thinking from first principles is a good starting point for all other types of thinking and mental models. If your assumptions are incorrect then the basis for any future thinking isn’t going to be accurate. In the 1600s René Descartes said he would "systematically doubt everything he could possibly doubt, until he was left with what he saw as purely indubitable truths." This is also called Cartesian doubt and is a systematic process of being skeptical about the truth of your beliefs. Simply put:

a. Write down all your major assumptions about a problem.

This might seem familiar to grade school. When solving a math problem a teacher would often ask you to state your assumptions and show your work. By writing them out you can take inventory of your current beliefs. It is likely that you'll look at them and think these all look right to me. Take note of how many of these assumptions are what we've come to call first principles.

b. Distill down your assumptions.

The next step is to break down your current assumptions into their fundamental parts. You can think about this as simplifying your assumptions further. This can be done using a technique such as the 5 whys discussed in the next section. While distilling down your assumptions keep in mind Occam's Razor which states that, "among competing hypotheses, the one with the fewest assumptions should be selected."

c. Distill your new assumptions done further.

Once you think you've distilled down your assumptions far enough, keep going. The idea is to go until you get to something that resembles an immutable fact. This might be difficult because depending on how you're judging the assumptions, distilling further may lead to a subjective result. The final result should be an objective one.

Watch for analogies. Humans like analogies because they're easy. "We're the Uber for X" or "We're the Tesla for X" as some of you may have heard. They have their place and are a shortcut for thinking, however they should be challenged if you're basing your decisions from them. Our brain is really good at creating shortcuts by making quick assumptions and that has served us well in the past. From a survival point of view being able to quickly make a decision based on what was done in the past worked to our advantage. Your brain will remember the solution you came up with last time and that brain path is primed to fire so that the next time you're approached with the same stimulus you begin with that solution and action. As the problem builds you'll start your thinking from that previous solution and build from there. It takes a conscious effort to change your behaviour when given that same stimulus.

I personally believe it is important to pay attention to social constructs and arbitrary restrictions. These are shared beliefs. Our social mind takes them as reality but going deeper you'll see that it is not always as it seems. Take for example countries. Countries and their borders aren't actually there, however we agree to them and live as such. These constructs are believed to be important for human's socially in order to keep peace. Debatable. But pay attention to ones that don't serve you and aren't necessary constraints. For example, when Elon Musk was exploring how to make space travel more affordable he discovered that the "higher grade" parts that were believed to be required for certain parts of a rocket were in fact not. And he figured out that they could do a lot of the manufacturing in house with raw materials to drive down the costs.

“I was trying to understand why rockets were so expensive. Obviously the lowest cost you can make anything for is the spot value of the material constituents. And that’s if you had a magic wand and could rearrange the atoms. So there’s just a question of how efficient you can be about getting the atoms from raw material state to rocket shape.” - Elon Musk

2. Ask Many Whys

You are probably familiar with asking the "5 Whys" because it's a common problem solving tool and used often to find the root cause of a problem. If you have children you are also familiar with what feels like 500 whys. Or perhaps you've still got that child-like curiosity and you ask those 500 whys. The question of "why" seeks to understand and challenge. By asking why you're automatically starting to challenge assumptions and find weaknesses in the responder's thought process. You already know how to do this but may have forgotten.

a. Choose a starting belief and ask why.

Answering the why may require further research into the belief you're questioning. If you strongly hold the belief to be true then it will be more of a challenge to start objectively asking the question why. As you begin to ask why about the belief, try to keep an open mind.

b. Once you've gotten your first answer(s) ask why again.

It may be helpful to start drawing a semantic tree to gain an understanding of what assumptions were required for your original belief to be true. This will help you keep track of what assumptions you've questioned and what beliefs were required for those assumptions to be true. When you do this you'll start going deeper and deeper down the rabbit hole. What you will find is that some assumptions are more critical to be true than others for your beliefs to be "true". I would suggest focusing on those first in this exercise. And of course Elon himself has his take on this: "It is important to view knowledge as sort of a semantic tree — make sure you understand the fundamental principles, like the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." If your assumptions form the trunk or big branches then it's critical to have them right.

c. And... Ask why again.

Keep asking why until you get to something that resembles an "immutable fact". This is very hard and I am by no means an expert in doing this type of exercise. Chances are by looking at your semantic tree of assumptions or truths you're going to end up with more questions than answers. I would say it's a good idea to get comfortable with the feeling of not actually knowing the answers. Acknowledging that you don't know the answer is an important step when it comes to reasoning from first principles. You must not fill in the gap with your best guess just so that you have an answer. This is like building a new house of cards with a bottom card that is weak and waiting to snap.

3. Start From Scratch

If you're starting from scratch, in theory, you're starting from first principles. This is actually a great way to learn. In grade school we start with the basic first principles of math. You don't just jump right into calculus before having an understanding of basic math operations. In order to start from scratch you need to scrap all your current beliefs and assumptions about a problem and begin from the ground floor. If your belief has some already standing first principles then you can start from there. However, I'd caution you to really consider and challenge the first principles you're starting from using your reasoning.

I think most innovation happens when you start thinking from the first basis. By starting from scratch and challenging longstanding assumptions you can change the game. Apple is said to have recently done this with their new M1 chip that launched the end of last year. John Gruber writes "To acknowledge how good they are — and I am here to tell you they are astonishingly good — you must acknowledge that certain longstanding assumptions about how computers should be designed, about what makes a better computer better, about what good computers need, are wrong." Apple embodies their previous slogan "Think Different" and everything that comes with that. While everyone else is up a few levels of thought built on assumptions and analogies, you're getting to the core to get ahead with first principles.

The three actions presented above provide you with a few ways of reasoning by first principles. I think that they're all intertwined and don't represent three isolated actions. They all help one another in the process of thinking by first principles. I've referenced these tools for challenging beliefs outside yourself (like product innovation) but they can also help you challenge and understand your own beliefs. I think the self can be one of the toughest things to break down to first principles. It takes courage. Perhaps a topic for another blog in the future.

I appreciate you.




My thoughts are subject to change and I will get some things wrong. I promise to keep learning and strive to keep doing better. I'm by no means an expert on any topic I may write or make videos about so always do your own research as well. I try to keep an open mind. If I can teach you something and also learn something from you then I'm doing what I set out to do. Thanks for reading. These are just some thoughts.

“Do the best you can until you know better. Then when you know better, do better.” - Maya Angelou

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