First Principles Thinking

What First Principles Thinking means

First principles thinking is the practice of stripping a problem down to the few things that must be true, then rebuilding the answer from only those. The line is simple. Owning it changes what we treat as fixed. We start to hear the word "because" and ask whether the reason still exists, or whether it belonged to someone who left years ago. We stop confusing a convention with a constraint. Before: the price, the process and the deadline are the walls of the room. After: most of the walls turn out to be furniture, and the two or three that are real, we can finally explain. It is not a licence to reject everything; it is knowing which walls are walls.

Not to be confused with

First principles thinking is not reasoning by analogy. Analogy says this is like that, so do what worked there. First principles says forget what worked there, what has to be true here, and builds up from that.

First Principles Thinking examples: where it shows up

• At work: the process nobody can defend but everybody follows, kept because removing it feels riskier than asking what it was for.
• With money: the price we accept because it is the price, until someone works out what the thing costs to make and builds a business in the gap.
• In our own careers: the path we follow because it is the path, when the things we actually need from a job might be reachable another way.

Where it sits

Concept 2 of 5 in The Foundations of Thought, a journey in the course The Examined Mind.

See where First Principles Thinking sits on the sky →

Nearest on the sky

• Abductive Reasoning
• Anchoring
• Beginner's Mind
• The Ladder of Abstraction
• Occam's Razor
• The Ship of Theseus

A filled dot marks a star that is already open to walk.