What I do find puzzling is why people seem so emotionally attached to the idea of general intelligence measured as a single number. Is there some political/educational aspect that I'm missing out on - I'm from the UK where IQ tests seem to be generally regarded with a high degree of healthy scepticism.
No, it's just the opposite. There is emotional attachment to the idea that intelligence cannot be measured with a single number - the idea that everybody is "good at something" with regard to cognitive skills; that there are different kinds of intelligence that are mostly orthogonal or even mutually exclusive. A mathematically highly skilled individual must be socially awkward or have poor language skills and so on. It would be unfair otherwise, after all.
On the other hand, the idea that there is a single number that correlates highly with most other definitions or aspects of "intelligence" has strong experimental backing, like it or not.
