@baldur

I've thought long and hard if I should answer, especially because I don't know your experience or knowledge of the subject, but I think you've got a wrong idea about what IQ tests are.

An IQ test does not measure the ability to convince oneself of something, nor others. E.g., there are many highly gifted people who are incredibly shy (and some are also anxious).

IQ tests are a lot more complicated than that, and usually try to measure intelligence across different topics.