Myths & Fact Checks
Viral IQ claims checked against the record: where the number came from, who repeated it, and what is actually documented.
Which MBTI Type Has the Highest IQ? What the Studies Show
The INTJ 130 and INTP 129 charts name no sample and no test. The best evidence finds a small IQ edge for Intuitive types, tied to openness, and the MBTI's publisher says it does not measure ability.
Do Twins Have Lower IQ Than Singletons? What the Data Shows
A UK cohort study once found twins scoring 5 to 6 points lower than singletons in childhood. A 2026 sibling-controlled study finds the gap has nearly closed — and reversed for one measure. That is a separate question from how heritable IQ is, which twin studies also answer.
Hamm v. Smith Decision: What the Court Left Open on Multiple IQ Scores
The Supreme Court took Hamm v. Smith to say how courts should weigh several IQ scores near 70, then dismissed it on 21 May 2026 without a holding. The opinions still lay out five scores, an SEM of 3 and two views of a lower bound of 69.
Is IQ Debunked? What Critics Get Right and Wrong
The score is stable, predicts exam results and survival, and is not debunked. What critics have challenged, with more success, is the idea that it is fixed, complete or explained by a single cause.
The Breakfast Question: Does It Really Reveal Low IQ?
A viral social-media test claims that answering a hypothetical breakfast question the wrong way proves low IQ. The claim traces to a single anonymous 2021 internet post with no named study behind it, though the psychology it distorts is real.
Zodiac Signs and IQ: Is Any Sign Actually Smarter?
No study has ever found a real link between star sign and measured intelligence. The pattern some people half-remember is either astrology's own vagueness at work, or a mix-up with a genuine, unrelated finding about relative age.
YoungHoon Kim's 276 IQ Claim: What Test Produced It?
YoungHoon Kim is widely described as having the world's highest IQ, 276. The number comes from a perfect score on a 32-question, untimed online test that allows internet use, normed on 32 test takers and stated on a scale with a standard deviation of 24. Here is what that score can and cannot mean.
Is the Dunning-Kruger Effect Real? What the IQ Data Actually Shows
In the famous 1999 study, students who scored at the 12th percentile guessed they ranked at the 62nd. When researchers later tested the effect against measured IQ, with statistics built to avoid a well-known trap, most of it disappeared. Not quite all of it.
The Left-Brain/Right-Brain Myth: What Brain Scans Actually Show
The idea that everyone leans on one dominant hemisphere — logical on the left, creative on the right — traces back to a real, Nobel Prize-winning discovery. It is not what that discovery found.
The "World's Most Intelligent Model" Ranks Fourth on Its Own Chart
OpenAI launched GPT-6 Astra on 3 September with that phrase. The one composite intelligence measure in the announcement's own comparison table puts it in fourth place.
Can Your IQ Change Over Time? What Retesting Shows
A Scottish cohort sat the same test at age 11 and again at 79, and the two sets of scores correlated at about 0.66. That single number refutes the claim that IQ is fixed and the claim that it is easily moved, because it is neither close to zero nor close to one.
Are Left-Handed People Smarter? What the Data Actually Shows
Pooled analyses of handedness and cognitive ability keep landing in the same place: an average difference near zero, small enough that no individual conclusion can be drawn from which hand someone writes with.
Does Birth Order Affect IQ? The Answer Is One Point, Maybe Two
Analyses that compare siblings inside the same family do find a firstborn advantage on measured intelligence — roughly one to two points on a mean-100, standard-deviation-15 scale. It is real, its size is disputed, and it is no larger than the error on a single test.
Does Music Raise IQ? What the Mozart Effect Study Actually Measured
The 1993 experiment behind three decades of "classical music makes babies smarter" ran for ten minutes, used college students, measured a single spatial task, and never mentioned IQ at all.
Celebrity IQ Figures: Almost None of Them Have a Source
The numbers attached to famous names travel for decades without ever acquiring a test record, a date or a scale. Where the trail can be followed at all, it usually ends at a magazine paragraph.
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