The path-neighborhood of a target in search-graph topology is not well-approximated by the similarity-neighborhood in feature space.
The stepping stones almost never resemble the final product.
Almost no prerequisite to any major invention was invented with that invention in mind.
Link to original
Consequence: ambitious objectives point away from their own stepping stones
Every stepping-stone example from Why Greatness Cannot Be Planned, where a prerequisite was invented/discovered without what it later enabled in mind Technology
- Vacuum tubes — investigated by Edison for electricity, refined by Fleming (1904) to detect radio waves → became the foundation of the ENIAC computer decades later.
- Induction coil — a high-voltage trigger for early electrical experiments → became a core part of the internal combustion engine.
- Induction coil in the Crookes tube — electrical experiment apparatus → discovery of cathode rays (electrons) → discovery of X-rays.
- Internal combustion engine — built for three-wheeled automobiles, printing presses, water pumps, machine tools → the engine the Wright brothers needed for the airplane.
- Bicycle (Wright brothers’ day job) → conceptual stepping stone to the airplane (“planes are bicycles in the sky”).
- Magnetron / microwave tubes — built for radar → microwave oven, after Percy Spencer noticed a chocolate bar melt in his pocket (1946).
- ENIAC (1946, 30-ton, vacuum-tube computer) → eventually the desktop PC, 25+ years later.
- Lithium-ion laptop batteries — consumer-electronics commodity → bundled into the Tesla Roadster, the first mass-produced electric sports car.
- Space race tech → cochlear implants, memory foam, freeze-dried food, improved emergency blankets.
Digital / software
- Dwarf Fortress + Roller Coaster Tycoon + Infiniminer → Notch combined ideas from all three into Minecraft.
- YouTube — launched as a video dating site → pivoted into video sharing.
- Flickr — a side feature of a social online game (itself inspired by a virtual-pets game) → the photo-sharing service outshone its parent.
- Nintendo playing cards (since 1889) → toys (the “Ultra Hand” mechanical extending arm) → video games / Super Mario.
Culture / art
- Jazz, blues, gospel, country → rock and roll (no one was trying to invent it).
- Ragtime → jazz.
- Impressionism (Monet) → Expressionism (Matisse) → Surrealism (Dalí) — each movement was not the goal of the preceding one.
- Calligraphy class Steve Jobs dropped in on → the typography of the Macintosh / personal computers.
Science / mathematics
- Group theory — pure abstract algebra pursued for its own sake → applications in chemistry and physics.
- One-way functions & computational complexity — pure mathematics → public-key cryptography and secure online commerce.
- Newton’s falling apple (chance observation) → universal law of gravitation.
- Pasteur’s accidental observations → discovery of chiral molecules and the process for bacterial vaccines.
- Archimedes in the bath → law of hydrostatics.
- Marcelino de Sautuola’s hobbies (caving + studying ancient artifacts) → discovery of the Altamira prehistoric cave paintings (1879).
Natural evolution (exaptation)
- Bilateral symmetry in flatworms — useful in their own niche → essential stepping stone to human-level intelligence.
- Multicellularity — a way to make a living → precondition for every complex animal.
- Feathers in dinosaurs — evolved for temperature regulation → later exapted for flight in birds.
- Mineral-storage bones — a chemical reservoir → later repurposed as the skeletal frame.
- Grass — a new plant niche → enabled herbivores, which enabled carnivores, scavengers, and parasites (a whole ecosystem cascade).