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Learn it by driving it.
Every figure is a model you can push until it breaks. Every number in the text is read off it.
Nobody gets there in a straight line. You overshoot, come back, overshoot less — and the thing you arrive at is yours in a way a sentence never is.
Your turn
Four things you will not believe until you move them
Four subjects, one bargain: the claim IS the readout, and the readout is computed. It moves on by itself until you touch it — then it is yours.
Shrink a circle and the error shrinks faster than the circle does. That is what makes the Jacobian a derivative rather than a nearby matrix.
F(x, y) = (x + 0.8y, 0.35x + y)
Linear, so the Jacobian is the same matrix everywhere and the circle is an ellipse at any radius. Nothing to shrink.
None of those can be handed to you in a sentence. That is the whole argument.
What is different
Numbers are computed, never typed
A figure cannot produce it, the text cannot print it. The build refuses.
Claims are swept, not sampled
“As this rises, that falls” is tested from a dozen states, not one.
Unverified says unverified
Eight claims went back to the papers. Six held. Two did not. All eight are in the text.
And what it cannot catch
Whether a chapter teaches. That needs a person, and it is where surviving errors live.
Why not a book, a lecture, a clip
What a book, a lecture, a clip give you
- A bookIts figure is a drawing of the answer. You cannot push it, and you cannot check the caption.
- A lectureThe discovery is theirs. You watch someone else find it, which is not the same operation.
- A clipThe punchline without the mechanism. Survives a dinner party, not a real problem.
What a team of agents under a harness gives you
- Claimstated so it can be proven false
- Attackfind the state where it breaks
- Buildmodel first, numbers fixed before it
- Writeprose read off the built model
- Reviewtwo critics, for what no check sees
All three are good at something and none of this replaces a good book. What did not exist is an order you can drive.
The shelf
Five routes in. Take them in any order.
The dependencies between them are real but weak, and insisting on a single order is what makes most curricula unfinishable.
- Agentic AIPython for AI engineers2 / 10
- Agentic AIThe mathematics underneath2 / 7
- Agentic AINeural networks and transformers0 / 10
- FinanceEconomics, from first principles4 / 6
- FinanceHedge funds, from first principles21 / 21
An education harness
Agents draft it. The harness is what makes that safe: they cannot publish what they cannot compute.
Runs on donated credits
No budget, nothing to sell. Spare AI credits this month? Write a chapter that belongs to everyone.