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A Lesson in Intelligence

Moravec's Paradox

The hardest things for AI are easy for toddlers.
The easiest things for AI are hard for PhDs.

In 1988, roboticist Hans Moravec made a puzzling observation: AI could beat chess grandmasters, prove mathematical theorems, and optimize complex logistics. But it couldn't walk across a room, recognize a face, or catch a ball.

Tasks that require years of human education - calculus, chess, logical reasoning - were relatively easy to program. Tasks that every toddler masters - walking, grasping objects, understanding social cues - remained almost impossibly hard.

"It is comparatively easy to make computers exhibit adult level performance on intelligence tests or playing checkers, and difficult or impossible to give them the skills of a one-year-old when it comes to perception and mobility."

- Hans Moravec, 1988

This isn't a quirk of AI design. It's a fundamental insight about what intelligence actually is and how evolution shaped our brains.

The things we think of as "hard" (chess, math) are recent evolutionary hacks.
The things we think of as "easy" (walking, seeing) are ancient and deeply optimized.
PART I

What AI Solved When

Explore the timeline of AI achievements. Notice a pattern: abstract reasoning tasks were solved decades before sensorimotor tasks. Chess fell in 1997. Walking is still being worked on.

AI ACHIEVEMENT TIMELINE
19502025

Abstract Reasoning

10

problems solved

Sensorimotor

5

problems solved

Logic Theorems
1956

Logic Theorist proved 38 of 52 theorems from Principia Mathematica

Human difficulty:9/10
AI difficulty:3/10
Backgammon
1979

BKG 9.8 defeated world champion Luigi Villa

Human difficulty:6/10
AI difficulty:3/10
Checkers
1994

Chinook became unbeatable world champion

Human difficulty:5/10
AI difficulty:2/10
Chess
1997

Deep Blue defeated world champion Kasparov

Human difficulty:8/10
AI difficulty:4/10
?Jeopardy!
2011

Watson defeated all-time champions Jennings and Rutter

Human difficulty:7/10
AI difficulty:5/10
Go
2016

AlphaGo defeated world champion Lee Sedol

Human difficulty:9/10
AI difficulty:5/10
Poker (No-Limit)
2017

Libratus defeated top professional players

Human difficulty:8/10
AI difficulty:6/10
🧬Protein Folding
2020

AlphaFold solved 50-year grand challenge

Human difficulty:10/10
AI difficulty:7/10
Math Olympiad
2022

AlphaGeometry solved olympiad-level geometry

Human difficulty:9/10
AI difficulty:7/10
Coding (Simple)
2023

LLMs pass most coding interviews

Human difficulty:7/10
AI difficulty:6/10
👁Image Classification
2012

AlexNet beat humans on ImageNet

Human difficulty:1/10
AI difficulty:6/10
🚶Stable Bipedal Walking
2024Unsolved

Robots can walk, but fail at uneven terrain

Human difficulty:1/10
AI difficulty:9/10
General Manipulation
2025Unsolved

Robots struggle to fold clothes, handle soft objects

Human difficulty:1/10
AI difficulty:9/10
👥Social Intuition
2025Unsolved

Reading body language, detecting sarcasm in real-time

Human difficulty:2/10
AI difficulty:9/10
🏠Physical Navigation
2025Unsolved

Navigating a cluttered kitchen while cooking

Human difficulty:1/10
AI difficulty:10/10

Notice: By 2025, AI has mastered chess, Go, poker, and protein folding.Yet robots still struggle to fold laundry.

Drag the slider through time. Watch how abstract tasks fall while physical tasks remain unsolved.

PART II

Human Ease vs AI Ease

If human difficulty correlated with AI difficulty, all points would cluster along the diagonal line. Instead, they split into two distinct groups: sensorimotor tasks (easy for humans, hard for AI) and abstract tasks (hard for humans, easy for AI).

HUMAN VS AI DIFFICULTY
Easy for Humans --> Hard for Humans
Easy for AI --> Hard for AI
MORAVEC ZONE
Easy human, Hard AI
AI SWEET SPOT
Hard human, Easy AI
Walk down stairs
Catch a ball
Recognize a friend in a crowd
Tie shoelaces
Tell if someone is lying
Pour water into a glass
Open a door
Fold a towel
Calculate 2847 x 9231
Play optimal chess
Memorize a phone book
Prove a theorem
Translate 100 documents
Beat a poker pro
Sensorimotor
Abstract reasoning

The diagonal line shows expected correlation. Points far from it reveal the paradox.

The paradox becomes clear: tasks in the upper-left (Moravec Zone) are trivially easy for humans but remain grand challenges for AI. Tasks in the lower-right (AI Sweet Spot) require years of human training but were among the first problems AI solved.

PART III

500 Million Years of Optimization

The explanation lies in evolution. Sensorimotor skills have been optimized for hundreds of millions of years. Vision evolved 540 million years ago. Locomotion even earlier. Every ancestor that was bad at these tasks was eaten.

EVOLUTIONARY OPTIMIZATION TIME

Evolution has spent vastly more time optimizing sensorimotor skills than abstract reasoning. The bar widths show relative optimization time (log scale).

Basic movement
500M yearsAI: TBD
Vision
450M yearsAI: 2012
Object manipulation
400M yearsAI: TBD
Social behavior
200M yearsAI: TBD
Facial recognition
100M yearsAI: 2014
Tool use
3M yearsAI: TBD
Language
200K yearsAI: 2023
Writing
5K yearsAI: 2023
Mathematics
4K yearsAI: 1956
Chess
2K yearsAI: 1997
Programming
75 yearsAI: 2023
Ancient sensorimotor
Primate-era
Recent abstract

Walking: 500 million years of optimization.
Chess: 1,500 years.
Guess which one is harder to engineer.

Abstract reasoning? Chess has existed for 1,500 years. Mathematics as a formal discipline for about 4,000 years. Programming for 75 years. Evolution has barely begun optimizing these skills.

This means sensorimotor tasks aren't actually "easy" - they're heavily optimized. Your brain dedicates massive computational resources to tasks you don't consciously notice. Abstract reasoning is a thin veneer on top of ancient, sophisticated machinery.

PART IV

Where Your Brain Spends Its Resources

The brain's resource allocation reveals the truth. Most of your neural real estate is dedicated to sensory processing and motor control - not abstract thought. The visual cortex alone uses a third of the cortex. The cerebellum, which coordinates movement, contains half of all neurons in the brain.

BRAIN RESOURCE ALLOCATION

Most of your brain is dedicated to sensorimotor processing - the "easy" tasks AI struggles with.

🧠

Sensorimotor Processing

80%

of brain resources

Abstract Reasoning

20%

of brain resources

Motor Cortex30%
Still struggling to replicate
Visual Cortex25%
Solved in 2012 (ImageNet)
Somatosensory15%
Major unsolved challenge
Cerebellum10%
Partially replicated
Prefrontal Cortex10%
LLMs approaching human level
Language Areas5%
Largely solved (GPT-4, etc.)
Math Processing5%
Solved since 1950s

When you catch a ball, your brain performs real-time calculations of trajectory, adjusting for wind, spin, and your own body position - all in milliseconds, unconsciously. When you solve a math problem, you consciously step through logic using a tiny fraction of your brain.

PART V

The Compute Behind "Easy" Tasks

Compare the computational resources required for different tasks. A chess move requires evaluating millions of positions. Walking requires coordinating hundreds of muscles, processing proprioceptive feedback, and making real-time balance adjustments - trillions of operations per step.

COMPUTE COMPARISON
🧠

Human Brain

Biological neural network

Neurons involved

100M

Time to complete

100ms

🤖

AI System

Silicon computation

Operations required

10.0B

Status

Recently solved (2012)

Chess requires ~200M AI operations. Walking requires ~1T per step.
That's 5,000x more computation for something a toddler does without thinking.

The difference is stark: tasks humans find effortless require vastly more computation than tasks humans find challenging. We just don't notice because evolution did the optimization work for us.

PART VI

Predictions: Confirmed and Pending

Moravec's paradox has proven remarkably predictive. We got language models before robot butlers. AI writes poetry while still struggling to fold towels. Understanding the paradox helps predict what AI breakthroughs will come next - and which will take decades longer than expected.

MORAVEC'S PREDICTIONS

Language models before robust robot helpers

Predicted: 1988

GPT-4 (2023) vs robot butlers still failing

AI will beat humans at Go before folding laundry

Predicted: 2000s

AlphaGo (2016) succeeded; laundry still unsolved (2025)

Self-driving cars will be "almost there" for decades

Predicted: 1990s

Still Level 2-3 in 2025, edge cases remain

AI writing before AI cooking

Predicted: 2010

ChatGPT writes essays; robot chefs still experimental

Medical diagnosis AI before surgical robot dexterity

Predicted: 2015

AI matches radiologists; surgery robots need human pilots

Moravec's paradox has been remarkably predictive.
Understanding it helps predict which AI breakthroughs will come next.

PART VII

What Will Be Solved Next?

Use Moravec's paradox to predict how hard any task will be for AI. The key question: does it require manipulating the physical world, or can it be done with pure computation?

PREDICT AI DIFFICULTY

Enter a task and use Moravec's paradox to predict how hard it will be for AI.

PART VIII

What This Tells Us About Intelligence

Moravec's paradox isn't just about AI - it reveals something profound about intelligence itself:

We Undervalue Embodied Intelligence

Walking, grasping, and sensing the world requires massive computation that we do not appreciate because it is unconscious. The simple tasks are computationally immense.

Abstract Reasoning is Overrated

Chess and calculus feel hard because we are bad at them - not because they are computationally complex. They are evolutionary afterthoughts built on ancient machinery.

Evolution is the Ultimate Optimizer

500 million years of optimization created solutions more sophisticated than anything we have engineered. We are still reverse-engineering walking.

LLMs Before Robots is Not Surprising

Language is a recent evolutionary development (~200K years). Of course we replicated it before sensorimotor skills. The paradox predicted this.

General AI May Arrive Backwards

We might achieve superhuman abstract reasoning while still struggling with basic physical tasks. AGI might be a disembodied genius.

Human Jobs Will Transform Unexpectedly

Knowledge work (abstract reasoning) is more vulnerable than physical work (sensorimotor). Lawyers before plumbers. Radiologists before nurses.

The Fundamental Insight:

What we call "intelligence" is mostly ancient sensorimotor optimization.
What we call "difficult thinking" is a thin layer of recent evolutionary hacks.
AI solved the thin layer first. The ancient machinery is still being decoded.

The hard problems are easy. The easy problems are hard.
Evolution knew all along.

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Reference: Moravec (1988), Brooks (1991)