This is an interesting study, but it begs the question: Was there really any serious doubt that Spearman's g is a general human trait, vs. a trait limited to Western cultures?<p>I realize that the mildly controversial nature of factor analysis plays into all of this, but the general concept of g is one of those things that seems to be intuitively obvious.<p>G by itself is a correlation factor that comes out of the numbers, but its essential nature is rather easy to summarize: Individuals that do well on one type of task that requires a level of cognitive ability tend to do well on unrelated tasks that also require a level of cognitive ability. G is an attempt to put a number to that correlation and thus to serve as a measure of general cognitive ability. The fact that g is defined as a hidden variable revealed by factor analysis doesn't really change the basic concept.<p>When described in that fashion, it seems ridiculous to imagine that that g could be anything but a universal human factor. For goodness sake, it can even be measured in some (non-human) mammals.<p>I would go so far as to say that if factor analysis did not find g in non-western cultures, this would say more about the reliability of factor analysis than it would about the existence of general cognitive ability.