From First Principles

From First Principles

Most answers are reasoned by analogy — "this is how it's done, so we do it too." First-principles thinking throws that out: it breaks the problem down to what's actually, physically, economically true, then rebuilds from those basics. The result often diverges sharply from convention, because the convention was inherited, not derived.

What This Skill Produces

• The fundamentals — the problem reduced to what's genuinely true (constraints from physics, math, economics, human needs), not what's assumed
• The inherited assumptions — the "that's just how it's done" beliefs, named and questioned (which are real constraints, which are just convention?)
• The rebuild — a solution reasoned upward from the fundamentals
• The divergence — where this differs from the default, and why the default existed anyway

Required Inputs

Ask for these if not provided:

• The problem or decision — what you're rethinking
• The current/default approach — how it's normally done
• The real goal — what you're actually trying to achieve
• The constraints you believe exist — so we can test which are real

Framework: Reduce, Question, Rebuild

1. Reduce to fundamentals. Ask "what do we know is actually true here?" — the real physical, economic, and human constraints, not the conventional wisdom.
2. Separate laws from conventions. Some constraints are unbreakable (physics, budget); many "constraints" are just how it's always been done. Sort them.
3. Question the conventions. For each inherited assumption, ask why — often the original reason is gone, or never applied to you.
4. Rebuild from the base. Reason a solution up from the fundamentals alone, ignoring the default path.
5. Compare to the default. Show where the first-principles answer diverges — and fairly consider why the convention exists (sometimes it's right; sometimes it's inertia).

Output Format

Problem: [what we're rethinking]

Fundamentals (actually true): [the real constraints/basics]. Assumptions to question

Rebuilt from basics: [the solution reasoned up from fundamentals]. Vs. the default: [where it diverges, and whether the convention still has a point].

Quality Checks

• The problem is genuinely reduced to fundamental truths
• Real constraints are separated from mere conventions
• Each inherited assumption is questioned with "why"
• The solution is rebuilt from the base, not tweaked from the default
• It fairly considers why the convention exists before dismissing it

Anti-Patterns

• Reasoning by analogy dressed up as first principles.
• Treating conventions as laws without testing them.
• Throwing out a convention that actually has a good reason.
• Stopping at "question everything" without rebuilding an answer.

Example Trigger Phrases

• "Think about this from first principles."
• "Why is this industry done this way — does it have to be?"
• "Challenge the assumptions behind how I'm approaching this."
• "Rebuild my morning routine from scratch, ignoring how I do it now."
• "Strip this problem to basics and reason it back up."