bramforgelabs.com › mental models › first principles thinking
Poor Charlie's Almanack · Concept #2

First Principles Thinking

"Reason from the ground up — not from the crowd down."

Two ways to approach a problem
❌ By Analogy
Borrowing from patterns
  • Copy how others have done it
  • Assume their constraints are yours
  • Inherit their blind spots
  • Arrive at the same answers
vs
✓ First Principles
Building from bedrock
  • Strip to fundamental truths
  • Separate physics from habit
  • Question every assumption
  • Rebuild from what's actually true
◈
The Decomposition Process
PROBLEM As presented INTERROGATE What do I assume? Which are habits vs facts? BEDROCK True constraints Real physics REBUILD New answer Insight or Clarity SEPARATE: ASSUMPTION → HABIT → PHYSICS
STEP 01
Identify & Name Assumptions
List every belief underpinning your position. Write them down. Most people skip this — that's the error.
STEP 02
Challenge Each One
Ask: is this true because of physics / logic — or because "that's how it's always been done"?
STEP 03
Rebuild from Bedrock
Using only verified truths, construct a fresh answer. It may look like the old one — or nothing like it.
"
You must not fool yourself — and you are the easiest person to fool. The antidote is to think in terms of first principles: what is actually true, stripped of all the opinion and convention layered on top.
— Charlie Munger, paraphrasing Feynman
Poor Charlie's Almanack · Mental Model Series · #02 of N