Opening · 6 min
How old is the maths behind AI?
Write one year: the newest piece of mathematics an assistant needs to answer you.
One guess, on your own
The free deck
Opening · 6 min
Write one year: the newest piece of mathematics an assistant needs to answer you.
One guess, on your own
The one idea
What changed was compute, data and one architecture.
Before the machines · 13 min
| Year | Idea | What it made possible |
|---|---|---|
| 1676 | Chain rule, Leibniz | Derivatives through nested functions |
| 1763 | Bayes, read to the Royal Society | Updating a belief when evidence arrives |
| 1805 | Least squares, Legendre | Fitting a curve to noisy measurements |
| 1847 | Gradient descent, Cauchy | Walking downhill to the best fit |
| 1906 | Markov chains | Predicting the next state from this one |
Before the machines
Gradient descent, with the chain rule spreading the blame back across the layers.
Machines that learn · 9 min
McCulloch and Pitts write a brain cell as mathematics.
The Dartmouth workshop coins “artificial intelligence”.
Rosenblatt’s perceptron adjusts its own weights.
Minsky and Papert show a single layer cannot do XOR.
Two winters · 9 min
The Lighthill report judged AI had not delivered, and British funding was cut.
The Lisp machine market collapsed as ordinary workstations got cheaper.
Backpropagation, published 1970 and popularised in 1986. LSTM in 1997.
Two winters
Both collapses followed promises sized for hardware that did not exist.
What actually changed · 11 min
ImageNet: 1.2 million labelled images, far more than anyone had trained on.
AlexNet on two GPUs: 15.3% top-five error against 26.2% for second place.
The transformer dropped recurrence, so training could run in parallel.
Scaling laws showed loss falls predictably as model, data and compute grow.
What actually changed
17th to 19th century mathematics.
None of it a new branch of maths.
The payoff
Nothing on the mathematics side had to be invented.
Applied exercise · 7 min
Take a feature you use and name the oldest piece of mathematics it depends on, the year it was published, and the gap between that year and the product shipping.
Close · 5 min
| Myth | What is actually true |
|---|---|
| “AI was invented in the last few years.” | Most of its maths is 17th to 19th century. |
| “Neural networks are a new idea.” | Rosenblatt built a learning machine in 1958. |
| “Hinton invented backpropagation.” | Linnainmaa published it in 1970; 1986 spread it. |
| “AI progress has been steady.” | Funding collapsed twice: 1974 and 1987. |
| “The transformer was a maths leap.” | It made training parallel. Scale did the rest. |
Check your history
Name two questions that test the claim.
What you’ll learn
Chain rule 1676. Bayes 1763. Gradient descent 1847. Centuries, not years.
The ideas arrived first. The compute and the data arrived much later.
What was promised, what shipped, and why the funding left twice.
GPUs, the internet as a training set, and one architecture: 2017.
Applied exercise
Take a feature you use and name the oldest piece of mathematics it depends on, the year it was published, and the gap between that year and the product shipping.
Cheat sheet
One page you keep: the questions to ask on every project, the rules of thumb, and a checklist you can use on your own product. All ten come with The Book.
Leave at the door
| Myth | What’s actually true |
|---|---|
| “AI was invented in the last few years.” | Most of its maths is 17th to 19th century. |
| “Neural networks are a new idea.” | Rosenblatt built a learning machine in 1958. |
| “Hinton invented backpropagation.” | Linnainmaa published it in 1970; 1986 spread it. |
| “AI progress has been steady.” | Funding collapsed twice: 1974 and 1987. |
| “The transformer was a maths leap.” | It made training parallel. Scale did the rest. |
Before you move on
A vendor calls their method a brand-new breakthrough.
Name two questions that test the claim.
How we would answer
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The Algorithm Archaeologist
excavates AI's forgotten experiments, spectacular failures and breakthrough moments, tracing how decades of wild ideas turned into the technology reshaping our world.
Episode 00 · How we got here
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