First principles thinking, or reasoning from first principles, is the most effective way to learn to think for yourself. All kids think from first principles, until they don’t.
“To understand is to know what to do.” — Wittgenstein
Elon Musk is probably the most famous person alive who thinks from first principles. Here is a good example about battery packs:
“… they would say, “historically, it costs $600 per kilowatt-hour. And so it’s not going to be much better than that in the future. So the first principles would be, what are the material constituents of the batteries? What is the spot market value of the material constituents? It’s got cobalt, nickel, aluminium, carbon, and some polymers for separation, and a steel can. So break that down on a material basis; if we bought that on London Metal Exchange, what would each of these things cost? Oh, jeez, it’s $80 per kilowatt-hour. So, clearly, you just need to think of clever ways to take those materials and combine them into the shape of a battery cell, and you can have batteries that are much, much cheaper than anyone realises.” — Elon Musk
Kids are naturally curious, and the way they express that curiosity is to keep asking why. That is first principles thinking in action. They want to get to the fundamental truth. Here’s a simple example.
Child: Why can’t I watch TV all day long?
Parent: Because it’s a waste of time.
Child: Why is it a waste of time?
Parent: Because you need to study.
Child: Why do I need to study?
Parent: Because it will make you smarter?
Child: Why does studying make me smarter?
Parent: BECAUSE I SAID SO.
A child who hears ‘because I said so’ enough times eventually stops asking why. They know the answer — because mum/day/teacher said so. They stop reasoning from first principles.
“The real world doesn’t come with instructions.” — Ana Lorena Fabrega
In school, kids are told to follow instructions. Not only do they not get the opportunity to think from first principles, they don’t get to think. Period. The real world doesn’t work like that. There’s no instruction manual to follow. Ana Lorena Fabgrega describes the real world as endless cycles of:
Try → Fail → Learn → Refine
First principles thinking is especially powerful when it comes to knowing what to try. Elon Musk applied first principles thinking to try to build a much cheaper battery pack. He did the same thing with rockets. Many parents want their child to be like Elon Musk. The truth is,
