to whom this post is dedicated in loving memory
Well, measuring so-called intelligence is not at all dissimilar to measuring so-called lying or deception. There is now a considerable body of scholarly material attesting to the fact that IQ tests – in particular, the long-venerated and seemingly respectable Stanford-Binet tests – do not measure 'intelligence' as such. IQ tests are supposed to measure, yes, intelligence but, at the risk of stating the obvious, before you can measure something you must first know what exactly you are measuring. The problem with IQ tests---well, one of many problems with them---is that the term intelligence has never been defined adequately, with the result that no one knows exactly what an IQ test is actually measuring. To put it bluntly, perhaps too bluntly, IQ tests measure one’s ability to do ... IQ tests. Yes, IQ tests. In the very early days of IQ testing, the American writer, reporter and political commentator Walter Lippmann said it all when he wrote, 'We cannot measure intelligence when we have not defined it.'
Perhaps more fairly, IQ tests, at their best, measure a certain kind of knowledge (yes, knowledge, of the kind learnt in school) and what is known as abstract problem-solving ability, that is, the ability to solve problems that are context free (i.e. not verbal or numerical in nature). That’s about the extent of it, despite apologists for IQ asserting that standard tests (eg Stanford-Binet) measure such skills as verbal reasoning, abstract/visual, quantitative, and short-term memory, which to a limited extent they do, but almost entirely under the umbrella of an all-too-often culture-bound learned (as opposed to intuitive) knowledge.
Lifestyle factors are also very important. For example, gamers -- or people who play a lot of computer games -- score higher on tests of reasoning and short-term memory. Smokers do poorly on tests assessing short-term memory and vocabulary, while test takers who have anxiety don't do as well on short-term memory tests.
What it all gets down to is this – IQ tests assume that intelligence is the ability to comprehend quickly, but is such ability the measure and determinant of intelligence or simply the result or by-product of intelligence? In any event, why should the ability to comprehend quickly be determinative of the matter? I know of no cosmic law to that effect.
Erstwhile friend Allan B, eat your heart out. Despite your assertions to the contrary, there is now a considerable body of peer-reviewed, statistical longitudinal material which debunks the old assertion that there was supposedly a direct and causal correlation between high IQ and career and socio-economic success. Clearly, IQ---whatever it is or isn't a measurement of---is not totally unimportant, but it is only one factor ... and not one of the more important ones at that. So, as Richard Nixon used to say, let me make one thing perfectly clear. The studies on IQ simply do not demonstrate unequivocally that what is being measured by the tests is the reason---that is, the cause---for the apparent greater success in the workplace and job market of higher-IQ children. Correlation does not imply causation.
Ha! There's no need to 'improve' one's IQ scores ... as if I didn't already know.
Note 2. Since I first wrote this post I have become aware of research---the largest single study into human cognition to date---that confirms that IQ tests are fundamentally flawed, as is the notion that human intelligence can be measured by IQ tests alone.