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Head-to-Head Comparison

Stephen Hawking vs William James Sidis

Stephen Hawking (IQ 180) vs William James Sidis (IQ 250). Side-by-side comparison of intellect, achievements, era and cultural impact.

Stephen Hawking
1942–2018 · GB
180
Estimated IQ
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William James Sidis
1898–1944 · US
250
Estimated IQ
Read full biography →
Born19421898
Died20181944
CountryGBUS
Estimated IQ 180 250
Best known forHawking radiation, A Brief History of Time, Penrose–Hawking theorems, Black hole information paradox, Micro black hole, Primordial black hole, Chronology protection conjecture,…The Animate And The Inanimate

Who had the higher IQ?

By the most cited estimates, William James Sidis tops this matchup with an estimated IQ of 250, a 70-point margin over Stephen Hawking (180). IQ estimates for historical figures are reconstructions, not test results — they sit on top of biographical evidence, productivity, and the difficulty of the problems each person solved. Treat the number as a directional signal, not a verdict.

Achievements compared

Stephen Hawking is best known for: Hawking radiation, A Brief History of Time, Penrose–Hawking theorems, Black hole information paradox, Micro black hole, Primordial black hole, Chronology protection conjecture,… William James Sidis is best known for: The Animate And The Inanimate

Recognition. Stephen Hawking: Adams Prize (1966) Eddington Medal (1975) Maxwell Medal and Prize (1976) Heineman Prize (1976) Hughes Medal (1976) Albert Einstein Award (1978) Albert Einstein Medal (1979) RAS Gold Medal (1985) Dirac Medal (1987) Wolf Prize (1988) Prince of Asturias Award (1989) Foreign Associate of the National Ac. William James Sidis: —.

Different eras, different boards

The two were born roughly 44 years apart (1942 vs 1898), which matters: scientific tools, available knowledge, and intellectual culture compound. Comparing minds across eras is comparing players on different boards.

The verdict

So who was greater? The honest answer: they're not strictly comparable. By raw IQ proxy, William James Sidis edges out. By measurable, lasting influence in their respective field, both are anchors of the human record. If you have to pick one to bet civilization on, pick the one working on the problem you care about.

Frequently Asked

Who had the higher IQ, Stephen Hawking or William James Sidis?
Estimated IQs are 180 for Stephen Hawking and 250 for William James Sidis. William James Sidis rates higher by 70 points. Historical IQ figures are reconstructions, not measured scores.
What is Stephen Hawking most famous for?
Hawking radiation, A Brief History of Time, Penrose–Hawking theorems, Black hole information paradox, Micro black hole, Primordial black hole, Chronology protection conjecture,…
What is William James Sidis most famous for?
The Animate And The Inanimate
Did Stephen Hawking and William James Sidis ever meet?
They were contemporaries, though there is no documented direct meeting in our sources.

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