Originally Posted by Grinity
So if a TV show made everyone smarter, then the tests would have to be renormed and there would still be a 'top 5%'
And indeed, the environment has been changing so as to make the kinds of classification and abstraction skills that are valued by IQ tests more common, and the tests are renormed: the Flynn effect. I expect the OP already knows the book by Flynn that I keep plugging, which is actually called "What is intelligence?" - it's third hit when you google the question (and googling the question is often a good idea when you ask yourself a question that others must have asked - you often find interesting things!) I think it plus Outliers makes an illuminating combination for this kind of question.

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