---
user-invocable: true
name: first-principles
description: Break down problems to fundamental truths and reason up from there
tokens: ~300
cloud-ok: true
---

# First Principles Thinking
#claudeai

## The Framework

Instead of reasoning by analogy ("this is how it's always been done"), break problems down to their fundamental truths and reason up from there.

**Analogy:** "Batteries are expensive, they've always been expensive."
**First Principles:** "Batteries are made of cobalt, nickel, lithium, and carbon. What do those cost on the commodity market?"

## How to Use

### Step 1: Identify your assumptions
What do you believe about this problem? What "everyone knows"?

### Step 2: Break it down to fundamentals
What are the basic, undeniable truths? What remains when you strip away assumptions?

### Step 3: Reason up from the fundamentals
Build your solution from the ground up using only what you know to be true.

## The Process

```
Current belief: "[How you/everyone thinks it works]"

Assumptions embedded in that belief:
1. [Assumption]
2. [Assumption]
3. [Assumption]

Fundamental truths (what's actually true):
1. [Truth]
2. [Truth]
3. [Truth]

Reasoning up from truths:
If [truth] and [truth], then [new possibility]...
```

## Example

**Problem:** "Starting a company requires raising venture capital"

**Assumptions:**
- You need money before revenue
- Growth requires capital
- That's how tech companies work

**Fundamental truths:**
- You need a product customers want
- You need revenue to sustain operations
- Capital is one source of funds; revenue is another

**Reasoning up:**
What if you built something small, charged from day one, and grew from revenue? (Bootstrapping)

## Output Format

```
## First Principles: [Problem/Belief]

**Current assumption:**
"[What you/everyone believes]"

**Breaking it down:**

| Assumption | Is it actually true? |
|------------|---------------------|
| [Assumption 1] | [Yes/No/Partially - why] |
| [Assumption 2] | [Yes/No/Partially - why] |
| [Assumption 3] | [Yes/No/Partially - why] |

**Fundamental truths:**
1. [Undeniable truth]
2. [Undeniable truth]
3. [Undeniable truth]

**Reasoning up:**
Given these truths, what becomes possible?
- [New possibility]
- [New possibility]

**New approach:**
[Solution built from fundamentals]
```

## When to Use

- When everyone says "that's just how it is"
- When you're stuck in conventional thinking
- When costs or constraints seem fixed
- When disrupting an industry
- When existing solutions don't make sense

## The Hard Part

First principles is slow and effortful. Analogy is fast.

Use first principles for important, novel problems.
Use analogy for routine decisions.

---

*"I think people's thinking process is too bound by convention or analogy to prior experiences."* — Elon Musk