It's called the g factor.
Whatever tests for any sort of intellegence you come up with, people who do well in one will tend to do well in another.
Supposedly with word association being the king of this heap. Proponents claim it has the highest correllation but I suspect this has to do with more well-read people tending to appear more intelligent in general.
Basically, there is a single general ability for intelligence underlying it all, and this is what IQ tests attempt to get at.
There are another group of correlations between tests, called s-factors.
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There are problems with this, of course.
Savant syndrome or idiot savant syndrome, which you probably already know of. Basically, one specific area of intelligence becomes overdeveloped, seemingly at the expense of others.
Autism also throws this a bit out of whack, especially as some are considering that autism may not actually be a defective condition.
Finally, certain areas of the brain control certain intelligences. If they are damaged, ability in a certain area can seriously suffer.
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Both the g-factor and multiple intelligences have a lot of support behind them.
Even if IQ tests had a serious white-male cultural bias, this is less the case now than it used to be. The g factor isn't just a stupid white male concept - many people who are brilliant in one area tend to be brilliant in many areas.
However, there are at least nine areas of 'intelligence' which can not only be localized to specific parts of the brain, but have autistic/idiot savant members who excel in one of these areas.
So far, these are:
1: Linguistic Intelligence. The ability to use language. Poets tend to have the most focus here, but any sort of writing works.
This does not govern how many languages a person knows, of course.
2: Logical-Mathematical Intelligence. Pretty self explanatory. Speaking from personal experience, the creative side of this is invention itself. Being able to see a problem and come up with a new way to solve it, I mean.
3: Spatial Intelligence. How well you can see with your mind, so to speak. Painters and sculptors tend to focus here.
4: Body-Kinesthetic Intelligence. How well you use your body. Hand-eye coordination included. On the creative side, dancers and actors specialize here.
5: Musical Intelligence. The ability to see and hear patterns. The creative side of this needs no explanation.
6: Interpersonal Intelligence. Empathy - how you deal with other people.
7: Intrapersonal Intelligence. 'Know thyself' - knowing your own abilities and limitations.
8: Naturalist Intelligence. The ability to differentiate between living things and other things in nature (rocks, clouds). On the creative side, it's also an aesthetic sense.
9: Moral 'Intelligence'. Distinguishing between right and wrong. It's kind of a half, but there are instances where people get a specific area of the brain destroyed and seem to lose all moral sense.
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I tend to think both are right. There is an overall general base, and, depending on how people's minds are forged, some will come out ahead of others.