...the outstanding feature of any famous and accomplished person, especially a reputed genius, such as Feynman, is never their level of g (or their IQ), but some special talent and some other traits (e.g., zeal, persistence). Outstanding achievements(s) depend on these other qualities besides high intelligence. The special talents, such as mathematical musical, artistic, literary, or any other of the various “multiple intelligences” that have been mentioned by Howard Gardner and others are more salient in the achievements of geniuses than is their typically high level of g. Most very high-IQ people, of course, are not recognized as geniuses, because they haven’t any very outstanding creative achievements to their credit. However, there is a threshold property of IQ, or g, below which few if any individuals are even able to develop high-level complex talents or become known for socially significant intellectual or artistic achievements. This bare minimum threshold is probably somewhere between about +1.5 sigma and +2 sigma from the population mean on highly g-loaded tests.
Childhood IQs that are at least above this threshold can also be misleading. There are two famous scientific geniuses, both Nobelists in physics, whose childhood IQs are very well authenticated to have been in the mid-130s. They are on record and were tested by none other than Lewis Terman himself, in his search for subjects in his well-known study of gifted children with IQs of 140 or above on the Stanford-Binet intelligence test. Although these two boys were brought to Terman’s attention because they were mathematical prodigies, they failed by a few IQ points to meet the one and only criterion (IQ > 139) for inclusion in Terman’s study. Although Terman was impressed by them, as a good scientist he had to exclude them from his sample of high-IQ kids. Yet none of the 1,500+ subjects in the study ever won a Nobel Prize or has a biography in the Encyclopedia Britannica as these two fellows did. Not only were they gifted mathematically, they had a combination of other traits without which they probably would not have become generally recognized as scientific and inventive geniuses. So-called intelligence tests, or IQ, are not intended to assess these special abilities unrelated to IQ or any other traits involved in outstanding achievement. It would be undesirable for IQ tests to attempt to do so, as it would be undesirable for a clinical thermometer to measure not just temperature but some combination of temperature, blood count, metabolic rate, etc. A good IQ test attempts to estimate the g factor, which isn’t a mixture, but a distillate of the one factor (i.e., a unitary source of individual differences variance) that is common to all cognitive tests, however diverse.
How much is this statistically correct? I agree with the fact that most high-IQ people are not outstanding geniuses, but neither are most non-high-IQ people. This only proves that high IQ alone is not a guarantee for great achievements.
I suspect a statistical error: ignoring a low prior probability that a human has very high IQ. Let me explain it by analogy—you have 1000 white boxes and 10 black boxes. Probability that a white box contains a diamond is 1%. Probability that a black box contains a diamond is 10%. It is better to choose a black box? Well, let’s look at the results: there are 10 white boxes with a diamond and only 1 black box with a diamond… so perhaps choosing a black box is not so great idea; perhaps is there some other mysterious factor that explains why most diamonds end in the white boxes? No, the important factor is that a random box has only 0.01 prior probability of being black, so even the 1:10 ratio is not enough to make the black boxes contain the majority of diamonds.
The higher the IQ, the less people have it, especially for very high values. So even if these people were on average more successful, we would still see more total success achieved by people with not so high IQ.
(Disclaimer: I am not saying that IQ has a monotonous impact on success. I’m just saying that seeing most success achieved by people with not so high IQ does not disprove this hypothesis.)
It’s interesting how one can read the excerpt in two different ways:
“wow, IQ isn’t all it’s cracked up to be, look at how none of the sample won Nobels but two rejected did”
“wow, in this tiny sample of a few hundred kids, they used a test which was so accurate in predicting future accomplishment that if the sample had been just a little bit bigger, it would have picked up two future Nobels—people whose level of accomplishment are literally one in millions, and it does this by only posing some boring puzzles without once looking at SES, personality, location, parents, interests, etc!”
Also, on typical test I’d expect well educated moderately high IQ person to have 100% success rate on everything that’s strongly related to intelligence. So at the top range the differences are driven by the parts that have much less direct relation (e.g. verbal, guess next in sequence, etc). Correlation is a line but real relation we should expect would be more like sigmoid as the relevant parts of test saturate. Furthermore, IQ test doesn’t test capacity to develop competence in a complex field.
Jensen on g and genius
How much is this statistically correct? I agree with the fact that most high-IQ people are not outstanding geniuses, but neither are most non-high-IQ people. This only proves that high IQ alone is not a guarantee for great achievements.
I suspect a statistical error: ignoring a low prior probability that a human has very high IQ. Let me explain it by analogy—you have 1000 white boxes and 10 black boxes. Probability that a white box contains a diamond is 1%. Probability that a black box contains a diamond is 10%. It is better to choose a black box? Well, let’s look at the results: there are 10 white boxes with a diamond and only 1 black box with a diamond… so perhaps choosing a black box is not so great idea; perhaps is there some other mysterious factor that explains why most diamonds end in the white boxes? No, the important factor is that a random box has only 0.01 prior probability of being black, so even the 1:10 ratio is not enough to make the black boxes contain the majority of diamonds.
The higher the IQ, the less people have it, especially for very high values. So even if these people were on average more successful, we would still see more total success achieved by people with not so high IQ.
(Disclaimer: I am not saying that IQ has a monotonous impact on success. I’m just saying that seeing most success achieved by people with not so high IQ does not disprove this hypothesis.)
It’s interesting how one can read the excerpt in two different ways:
“wow, IQ isn’t all it’s cracked up to be, look at how none of the sample won Nobels but two rejected did”
“wow, in this tiny sample of a few hundred kids, they used a test which was so accurate in predicting future accomplishment that if the sample had been just a little bit bigger, it would have picked up two future Nobels—people whose level of accomplishment are literally one in millions, and it does this by only posing some boring puzzles without once looking at SES, personality, location, parents, interests, etc!”
Good point.
Also, on typical test I’d expect well educated moderately high IQ person to have 100% success rate on everything that’s strongly related to intelligence. So at the top range the differences are driven by the parts that have much less direct relation (e.g. verbal, guess next in sequence, etc). Correlation is a line but real relation we should expect would be more like sigmoid as the relevant parts of test saturate. Furthermore, IQ test doesn’t test capacity to develop competence in a complex field.