🔬 Beginner
First-Principles Thinking
Reason up from what you know is true instead of by analogy. Boil a problem down to its irreducible facts, then rebuild — the engine behind every breakthrough.
Coming soon
1 courses / 6 lessons / ~1h of learning
/ 0 prerequisites
Learn it the way
you'd learn to
ride a bike
.
Not by memorising definitions — by grabbing the thing and feeling how it moves. Start from zero; finish an expert, one rung of the ladder at a time.
- Free forever
- No account
- No ads
- Open source
- English + Español
01
Start from absolute zero
No jargon assumed. Course one assumes you have never met the subject before — and every later course only leans on the ones before it.
02
You poke it, not read it
Sliders, step-throughs, quizzes in every lesson. The idea moves when you move it, which is the difference between "I read that" and "I get that".
03
It doesn’t stop at “intro”
Most explainers tap out right after the basics. These keep climbing, all the way to expert depth, until the advanced stuff is just stuff you know.
One ladder, no gaps
Every course stands on the one below it.
Most sites give you scattered explainers. This is a single dependency graph: each course only assumes the ones before it, from the very first idea all the way to expert depth. You are never expected to know something you weren't taught.
- Beginner 1/41 courses
The absolute basics — no prior knowledge assumed, every term defined on first use.
- Intermediate 2/40 courses
The working vocabulary and the ideas the rest of the path leans on.
- Advanced 3/40 courses
Real depth, assuming the earlier rungs are behind you.
- Expert 4/40 courses
The deepest, most rigorous tier — practitioner-grade, all the way to the edge.
The full map lives in the catalog — a real dependency graph you can follow course by course.
The whole map
1 courses. This is all of them.
From the very first idea to the deep end — every chip below is a full course you can open right now.
How a lesson works
Built on how memory actually works.
Reading feels like learning; it mostly isn't. Every lesson here forces the three things that do work: predict, interact, retrieve.
- 1
Guess before you’re told
Lessons open with a question you can’t answer yet. Committing to a guess first is what makes the real answer stick — it’s the testing effect, and it’s built into every lesson.
- 2
Grab the idea
Every core concept ships with a slider, animation or step-through. The idea isn’t a paragraph here — it’s something you bend with your own hands.
- 3
Prove you got it
Quizzes, concept matchers, fill-in-the-blanks and spot-the-trap questions — varied on purpose, spaced through the lesson, never a wall of MCQs at the end.
- 4
Pass the final
Each course ends in a graded final exam: one shot per question, no retries, score at the end. Progress saves on your device — no account, ever.
Learning Paths
Curated tracks, not one giant list.
Pick the area you care about and follow the graph from beginner to expert — or jump straight to the course you need.
🧱
Foundations
Start here. What a mental model is, the latticework idea, and the base models everything else builds on — map vs. territory, first principles.
1 courses Beginner → Beginner
⚖️
Decision-Making & Judgment
Choosing well under uncertainty: inversion, second-order thinking, opportunity cost, margin of safety and expected value.
0 courses Beginner → Beginner
🎲
Probability & Uncertainty
Thinking in odds: base rates, Bayesian updating, regression to the mean, fat tails and sample size.
0 courses Beginner → Beginner
🧠
Human Nature & Bias
How minds misfire: the major cognitive biases, incentives, social proof and commitment & consistency.
0 courses Beginner → Beginner
🔄
Systems & Feedback
Wholes over parts: feedback loops, stocks & flows, bottlenecks, emergence and leverage points.
0 courses Beginner → Beginner
📈
Economics & Markets
Incentives at scale: supply & demand, comparative advantage, externalities and the tragedy of the commons.
0 courses Beginner → Beginner
🧩
Problem-Solving
Cracking hard problems: first principles, inversion, thought experiments and Occam’s & Hanlon’s razors.
1 courses Beginner → Beginner
⚙️
Science & Engineering
Borrowed from the hard sciences: critical mass, equilibrium, leverage, compounding and algorithms.
0 courses Beginner → Beginner
🧬
Biology & Evolution
Models from life itself: natural selection, adaptation, ecosystems and niches, and the Red Queen effect of constant co-evolution.
0 courses Beginner → Beginner
♟️
Strategy & Competition
Winning repeated games: game theory, moats, comparative advantage and the Red Queen effect.
0 courses Beginner → Beginner
Coming Soon
Coming Soon →
The ladder keeps growing.
What's next on the build queue — the courses being added to the zero-to-expert ladder, in the order they'll arrive.
🔃 Beginner
Inversion: Think Backwards
“Invert, always invert.” Instead of asking how to succeed, ask how to fail — then avoid that. One of the most powerful and underused thinking tools.
Coming soon
🌊 Intermediate
Second-Order Thinking
“And then what?” Trace the consequences of the consequences. First-order answers are easy and usually wrong; the edge is in the ripple effects.
Coming soon
Start at zero. Finish an expert.
1 courses, 6 lessons, one ladder — free, no account, in English and Spanish. It takes about ten seconds to start.