★★★★★

Vehicles

Experiments in Synthetic Psychology
Valentino Braitenberg · 1984
"Science fiction in the service of science. Not for amusement."
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Vehicle Builder Sandbox

Wire up a vehicle. Drag light sources. Watch behavior emerge.

Select a preset or configure wiring
Tap canvas to place light sources. Drag them around.

14 Vehicles, 14 Upgrades

Each vehicle adds one mechanism — and a new layer of apparent psychology emerges.

Name That Behavior

You see the wiring. What does the vehicle do?

Question 1 of 6

The Law of Uphill Analysis

Simple wiring → complex-looking behavior. Watch a trivially wired vehicle produce trajectories you'd never guess came from two sensors and two motors.

"It is pleasurable and easy to create little machines that do certain tricks. But it is much more difficult to start from the outside and to try to guess internal structure just from the observation of behavior."— Braitenberg, Vehicle 5
Watch the trajectory. Can you guess the wiring?

Threshold & Memory

Add a threshold and watch a vehicle appear to "ponder" before acting. Add memory and watch it learn from experience.

0.30
Vehicle sits still until stimulus exceeds threshold — then acts decisively. "Where decisions are being made, there must be a WILL to make them."

The Complete Vehicle Catalog

Best Quotes

Synthetic Psychology

Braitenberg's case for building minds to understand them.

🔽 Downhill Invention

Building a machine that exhibits fear, love, or will is easy. You just wire sensors to motors with the right sign and topology. The behavior emerges for free — often exceeding what you planned.

🔼 Uphill Analysis

Observing a behaving creature and reverse-engineering its mechanism is fiendishly hard. Multiple mechanisms produce identical behavior. We always overestimate internal complexity.

🧬 The Asymmetry

This is why consciousness seems mysterious. We're stuck doing uphill analysis on brains that were built downhill by evolution. The "hard problem" may be an artifact of perspective, not metaphysics.

🔬 The Method

Instead of analyzing complex brains, build simple vehicles and watch what behaviors emerge. Start simple, add one mechanism at a time, and let psychology dissolve into engineering.

🧠 Two Kinds of Knowledge

Mnemotrix: "what goes with what" — concepts, association, nouns. Ergotrix: "what follows what" — causality, rules, verbs. Together they make a world model. Like vocabulary and grammar.

🎲 Chaotic Free Will

Vehicle 12's train of thought is mathematically chaotic — iterating a humped function. Unpredictable even in principle. Braitenberg argues: if you can't predict it, you can't deny it free will.

★★★★★

Vehicles is one of those rare books that changes how you think, permanently, in under 150 pages.

It belongs in the same category as The Selfish Gene or Gödel, Escher, Bach — books that give you a new mental framework you'll use for the rest of your life. By building up from nothing — one sensor, one motor — Braitenberg makes you feel each level of complexity. Fear, love, will, foresight, and optimism emerge not as mysterious essences but as inevitable consequences of wiring.

The law of uphill analysis is one of the most important ideas in cognitive science. It explains why we over-attribute intelligence, why the "hard problem" feels hard, and why AI seems both trivially simple and impossibly complex depending on which direction you look.

Written in 1984, it anticipates neural networks, evolutionary algorithms, reinforcement learning, and embodied cognition — all framed more clearly than most modern textbooks.

Limitations: The biological notes are dense and dated. Later vehicles (10–14) get sketchier — ideas grow bigger but mechanisms get hand-wavy. No actual implementation — which makes it perfect for building demos.

The bottom line: Braitenberg proves, delightfully, that you don't need to understand a mind to build one — and that building one is the best way to start understanding.