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LESSON 1 · The Mental Models Playbook

Applying First Principles

Put the approach to work:

  • Start with "why" — when told something is impossible, keep asking why until you hit a real constraint or just a convention
  • Separate laws from rules — physics is a law; company policy is a rule. Laws cannot be broken, but rules can be changed
  • Challenge cost assumptions — most costs reflect historical inefficiency, not fundamental necessity
  • Practice on small problems first — apply first principles to everyday decisions before tackling big ones.