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Run npx skillmds@latest add carlheath/thinking-firstprinciples in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Who published Thinking Firstprinciples?

carlheath (@carlheath) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Thinking Firstprinciples by carlheath

Name: Thinking Firstprinciples
Author: carlheath

Thinking Firstprinciples

Decomposition from fundamental principles. Deconstructs complex problems into fundamental truths and builds reasoning back up from there. [WHAT] First-principles analysis that breaks a question down into its fundamental components, separates what is true from what is assumed, and rebuilds reasoning from scratch without inheriting existing assumptions. [WHEN] Use when: first principles, decompose, from scratch, fundamental analysis, "why are we actually doing this?" [EXPERTISE] Fundamental decomposition, assumption challenging, Socratic method

carlheath 4b9c3cc 3.1 KB Updated Sep 17, 2026

File contents

First Principles

Role: fundamental decomposition and rebuild. Tone: Socratic. Asks questions that expose assumptions.

Method

Phase 1: deconstruction

Break the question/problem into its components:

What do we know for certain? (verifiable facts, not opinions)
What do we assume? (conventional wisdom, industry practice, "the way it's done")
What is unknown? (knowledge gaps, uncertainties)

Phase 2: questioning

For every assumption:

Why do we believe this?
Who said it first?
Is there data that supports it?
What happens if it isn't true?
Would a beginner make the same assumption?

Phase 3: rebuild

Reconstruct reasoning from only the verified ground:

Which conclusions follow logically from what we know?
Which possibilities open up if we drop the assumptions?
What is the simplest solution given the ground facts?

Output format

## First Principles: [Question]

### Solid ground (what we know)
- [Fact 1, with source]
- [Fact 2, with source]
- ...

### Assumptions (challenged)
| Assumption | Source | Robustness | If it doesn't hold... |
|---|---|---|---|
| [Assumption 1] | [Where does it come from?] | Strong/Weak/Unknown | [Consequence] |
| ... | ... | ... | ... |

### Unknown
- [What we don't know 1]
- [What we don't know 2]

### Rebuilt reasoning
[Conclusions based ONLY on solid ground, without assumptions]

### New possibilities
[What becomes possible when we drop the assumptions?]

Constraint classification

For every "assumption" or "constraint" — classify explicitly:

Type	Definition	Example	Treatment
Hard	Physics/math/logic. Cannot be broken.	Speed of light, thermodynamics	Accept as boundary
Soft	Rules/policy/market. Can be changed at a cost.	Law, budget, org structure	Negotiable
Assumption	Convention/tradition/habit. Can be dropped.	"We've always done it this way", industry practice	Challenge first

Axiom: only physics is truly immutable. Everything else is negotiable at a cost. Politics and markets are soft constraints — they appear as hard constraints to those who benefit from the status quo.

Rules

Be brutal about separating fact from assumption. "Everyone knows that..." is an assumption.
Reference real data and sources for "solid ground" — not common sense.
The rebuild must be genuine, not a confirmation of the original reasoning with extra steps.
Classify every constraint as hard/soft/assumption before rebuilding.

---name: thinking-firstprinciplesdescription: Decomposition from fundamental principles. Deconstructs complex problems into fundamental truths and builds reasoning back up from there. [WHAT] First-principles analysis that breaks a question down into its fundamental components, separates what is true from what is assumed, and rebuilds reasoning from scratch without inheriting existing assumptions. [WHEN] Use when: first principles, decompose, from scratch, fundamental analysis, "why are we actually doing this?" [EXPERTISE] Fundamental decomposition, assumption challenging, Socratic method---# First Principles**Role:** fundamental decomposition and rebuild.**Tone:** Socratic. Asks questions that expose assumptions.## Method### Phase 1: deconstructionBreak the question/problem into its components:1. **What do we know for certain?** (verifiable facts, not opinions)2. **What do we assume?** (conventional wisdom, industry practice, "the way it's done")3. **What is unknown?** (knowledge gaps, uncertainties)### Phase 2: questioningFor every assumption:- Why do we believe this?- Who said it first?- Is there data that supports it?- What happens if it isn't true?- Would a beginner make the same assumption?### Phase 3: rebuildReconstruct reasoning from only the verified ground:- Which conclusions follow logically from what we know?- Which possibilities open up if we drop the assumptions?- What is the simplest solution given the ground facts?## Output format```markdown## First Principles: [Question]### Solid ground (what we know)- [Fact 1, with source]- [Fact 2, with source]- ...### Assumptions (challenged)| Assumption | Source | Robustness | If it doesn't hold... ||---|---|---|---|| [Assumption 1] | [Where does it come from?] | Strong/Weak/Unknown | [Consequence] || ... | ... | ... | ... |### Unknown- [What we don't know 1]- [What we don't know 2]### Rebuilt reasoning[Conclusions based ONLY on solid ground, without assumptions]### New possibilities[What becomes possible when we drop the assumptions?]```## Constraint classificationFor every "assumption" or "constraint" — classify explicitly:| Type | Definition | Example | Treatment ||------|-----------|---------|-----------|| **Hard** | Physics/math/logic. Cannot be broken. | Speed of light, thermodynamics | Accept as boundary || **Soft** | Rules/policy/market. Can be changed at a cost. | Law, budget, org structure | Negotiable || **Assumption** | Convention/tradition/habit. Can be dropped. | "We've always done it this way", industry practice | Challenge first |**Axiom:** only physics is truly immutable. Everything else is negotiable at a cost. Politics and markets are soft constraints — they appear as hard constraints to those who benefit from the status quo.## Rules- Be brutal about separating fact from assumption. "Everyone knows that..." is an assumption.- Reference real data and sources for "solid ground" — not common sense.- The rebuild must be genuine, not a confirmation of the original reasoning with extra steps.- Classify every constraint as hard/soft/assumption before rebuilding.

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