First Principles
Thinking
You want to eat better this month. You copy the meal-kit subscription a friend uses, download three recipe apps, and fill a cart with special ingredients you have never cooked. The bill lands at triple your normal grocery spend, and you have not made a single dinner yet.
What is First Principles Thinking?
First Principles Thinking is a problem solving method that breaks a problem down to its most basic truths and rebuilds an answer from those truths alone. You strip away every assumption you inherited, every "this is just how it's done," until you reach facts that stand on their own. From there you build back up, using only what survived the strip-down. The approach traces back to Aristotle, who used "first principles" to mean the basic facts a subject rests on.
Most hard problems feel hard because they carry a stack of assumptions you never checked. Copying what other people did works right up until your situation differs from theirs in a way that matters, and then the borrowed answer quietly fails. Breaking a problem down to basic truths shows you which parts of the common answer are real constraints and which are only habit, so you can change the parts that were never fixed to begin with.
How to use it
Run any stuck problem through five steps. A pen, paper, and a willingness to question the obvious are all you need.
- Write the problem as a goal, not a solution.
State what you actually want, for example "eat healthy dinners on a tight budget," rather than "find a cheaper meal kit." A goal keeps your options open, so you do not lock yourself into one path before you understand the problem. - List every assumption you are making.
Write down what you believe must be true: dinners need special ingredients, cooking takes an hour, healthy means expensive. Get them all onto the page where you can see them. - Test each assumption against what is actually true.
Ask of each one whether it is a hard fact or an inherited belief. A healthy dinner needs vegetables, a protein, and heat. It does not need a subscription or a rare ingredient. - Rebuild an answer from the truths that survive.
Use only the facts left standing to construct a fresh solution. Basic vegetables, eggs or beans, and twenty minutes cover the real requirement at a fraction of the cost. - Check the rebuilt answer against your goal.
Confirm the fresh solution meets the goal you wrote in step one, and adjust any piece that falls short before you commit to it.
Worked example
You want healthy dinners without spending a fortune. Instead of hunting for a cheaper meal kit, you write the real goal: five healthy dinners a week on a tight budget. Then you list your assumptions. You believe healthy food is expensive, that a good dinner takes an hour, and that you need recipes you do not own.
You test each belief. Vegetables, rice, eggs, and dried beans are cheap and healthy, so "expensive" fails the test. A stir-fry takes fifteen minutes, so "an hour" fails too. You rebuild from what remains true: buy a handful of cheap staples, cook two simple bases on Sunday, and vary them through the week. The plan costs less than half the meal kit and takes less time, because you built it from the facts rather than from what your friend happened to buy.