Over two thousand years ago, Aristotle defined a first principle as the "first basis from which a thing is known." It is foundational in that it cannot be deduced from other assumptions. It's like an element. It is pure.
Today this approach has been popularised by the likes of Elon Musk, Charlie Munger and Naval Ravikant. It allows them to cut through clouded judgement and inadequate analogies to foresee opportunities that others miss.
First principles thinking one of the best ways to reverse-engineer complicated problems and unlock creative possibility. It's the process of breaking down complex problems into basic elements and reassemble from the ground up - providing ways to learn to think for yourself, and move from linear to non-linear results.
It's one of the best mental models you can use to improve your thinking because the essentials allow you to see where reasoning by analogy may lead you astray.
Chef vs Cook
I get the irony but let me explain it with an analogy of a cook and a chef that might resonate. Everyone is somewhere on the spectrum of being a chef and a cook. While the terms are often used interchangeably, there is an important nuance. The chef is a pioneer, the person who invents recipes. She understands the raw ingredients and how best to combine them. The cook, who reasons by analogy, uses a recipe. He creates something, perhaps with slight variations, that's already been created. The results is always a derivate of something that already exists.
The difference between reasoning by first principles and reasoning by analogy is like the difference between a chef and a cook. The chef understands the flavour profiles at such a fundamental level that she doesn't need a recipe to produce something great. However, if the cook loses the recipe, he'd be screwed (much like the situation at home for me). It's the difference between real knowledge and know-how.
Techniques for establishing first principles
While Socratic questioning may sound like a normal line of questioning, it seeks to draw out first principles in a systemic manner. It generally follows this process:
Questions for clarification (Why do you say that? What exactly do I think?)
Questions that challenge assumptions (What could we assume instead? What if I thought the opposite?)
Questions that probe reasons and evidence (Is there data to back this up? What are the sources?)
Questions about different perspectives (What is another way to look at it? How do I know I am correct?)
Questions that probe implications and consequences (What am I implying? What are the consequences if I am?)
Questions about the question (What was the point of this question? Why do you think I asked this question?)
This process helps you build something that lasts.
The Five Whys
Every parent is probably aware of this. Children instinctively think in first principles, they want to understand what's happening in the world. However annoying it may be for adults, they try to break the fog with a game some parents have come to hate. It goes something like this:
As long as you don't find yourself replying with "because I said so", or "because that's how it is" you're probably on the right path. Use this methodology to introspect your own understanding of things.
Using first principles in your daily life
We're full of big ideas, dreams and energy when we're young. We have no problem thinking about what we want to achieve in life. I always wanted to be an astronaut. It didn’t work out, yet.
The problem is we let others tell us what's possible, and more importantly we let them tell us how to get there. And when we let that happen, we outsource our thinking to someone else. Everything we do ends up being a derivate of someone else's thinking.
I do believe analogies are beneficial; they make complex problems easier to communicate and understand. However, they come with a hidden cost at times when you least expect it. I’ve found reasoning by first principles to be useful when I am:
Doing something for the first time
Dealing with complexity
Understanding root causes of problems
You can learn a lot more than you think you can.