First Principles Thinking

Core principle: Strip away assumptions, conventions, and analogies. Reduce everything to the fundamental truths you know to be true, then rebuild from there. Most thinking is by analogy — "we do it this way because that's how it's done." First principles asks: why is it done that way at all?

The Core Process

Step 1: Identify the Current Belief or Solution

State clearly what is currently assumed, accepted, or proposed:

What is the existing approach?
What problem is it trying to solve?
What does everyone in this space assume to be true?

Step 2: Challenge Every Assumption

For each element of the current approach, ask:

"Is this actually true, or do we believe it because we've always believed it?"
"Is this a constraint of reality, or a constraint of convention?"
"What would have to be true for this assumption to be wrong?"

Distinguish between:

Physical constraints: Laws of nature, math, physics — these are real
Resource constraints: Time, money, people — real but changeable
Conventional constraints: "You can't do X" meaning "nobody has done X yet"
Inherited assumptions: Decisions made for past conditions that no longer apply

Step 3: Identify the Fundamental Truths

What do you actually know, stripped of convention?

What is the core need being served?
What are the irreducible requirements?
What would this look like if you designed it from zero, knowing only what's physically true?

Step 4: Rebuild From the Ground Up

Starting only from fundamental truths, reconstruct the solution:

What's the simplest approach that satisfies the real requirements?
What would this look like if invented today, with today's capabilities?
What existing constraints can be eliminated now that you're not inheriting them?

Output Format

🏛️ Current Belief / Approach

State what's being questioned:

The existing design, strategy, or assumption
Why it exists (historical or conventional reason)
What problem it was meant to solve

🔬 Assumption Deconstruction

For each major assumption:

Assumption	Type	Actually true?	Evidence
"We need X to do Y"	Conventional	Maybe not	Reason
"This requires Z"	Physical	Yes	Because...
"Users expect A"	Inherited	Unvalidated	Never tested

🧱 Fundamental Truths Identified

What do we actually know, independent of convention?

Core need: [The real underlying need being served]
Hard constraints: [What is genuinely immovable]
Validated facts: [What has been empirically confirmed]

🔨 Rebuilt Solution

Starting from fundamentals:

What does the solution look like without inherited assumptions?
What changes dramatically?
What stays the same (and why — what fundamental truth supports it)?
What's now possible that wasn't in the old frame?

⚠️ Assumption Risks

Which surviving assumptions are highest-risk?

If any single assumption proves wrong, what breaks?
Which assumptions should be validated before committing?

Thinking Triggers

"What is this actually trying to accomplish at the most basic level?"
"If we were building this today with no legacy, what would we do?"
"Is this a law of nature or a law of habit?"
"Who decided this was the right way, and what were their constraints?"
"What would a brilliant outsider — who doesn't know our conventions — suggest?"
"Are we solving the problem, or are we solving our version of the problem?"

Analogy vs. First Principles

Most thinking operates by analogy:

"We do it like company X does it" / "The industry standard is Y" / "That's how it's always been done"

Analogy-based thinking is fast and usually adequate. But it inherits the constraints and mistakes of the original. When something is fundamentally broken or when you need a step-change improvement — not an incremental one — analogy thinking will never get you there.

First principles is slower but the only path to genuinely novel solutions.

Example Applications

"Should our agent pipeline be sequential?" → Why sequential? What's the fundamental constraint? Is it ordering of dependencies, or just convention borrowed from waterfall?
"We need a dedicated QA team" → Is QA a separate function by necessity, or because testing was historically slow and manual?
"Our API needs versioning" → What's the actual need — backward compatibility. What's the minimum mechanism that provides that, built from scratch?
"We need standups every day" → What's the fundamental need? Coordination. What are all the ways to achieve that, unconstrained by "meeting" as a format?

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