I am skeptical that high IQ correlates to success in all areas. Doesn't it depend on the person's area of expertise, and, in our culture, people skills? If you have a high IQ but esoteric interests and a loathing of society, you'd probably do less well than a high average person who loves to play the game, it seems to me.
Yes, that's why the word is correlates, not controls. Say you go out and randomly grab 3000 people off the street and give them IQ tests, then sort them into the top 1000, the middle 1000, and the lowest 1000. The top thousand might have an average IQ of 115, the middle group would average 100, and the bottom group might average 85. The top group -- as a group, though individuals will vary
-- will make more money, spend less time in jail or in the unemployment line, be healthier, and be less likely to be divorced or have illegitimate children than the middle group. Ditto the middle group over the bottom group. Significant correlations have been found in all those areas and more; they just don't get any play in the media because they violate the liberal blank slate ideology and have unpleasant social implications.
Interestingly, despite being wealthier, healthier, and generally doing better in life, no correlation has been found between IQ and happiness. I guess that just proves what we know as Catholics, that true happiness doesn't come from the material world.
Of course there are other attributes that affect success in life, like sociability, fortitude, ambition, creativity, and so on. IQ is just one of the factors, but an important one. And since it's measurable with considerable accuracy, we're better able to measure its importance than we can something like sociability.
Again, none of this means someone from the 90 IQ group can't become wealthy and healthy, have a good marriage, and so on. It just affects the odds, but those odds aren't absolute and can be overcome. Spud Webb made it to the NBA despite only being 5'6", but he had to work harder and have a lot more talent than a 7-footer to do it.
The problem we have with the modern liberals like George W. Bush and their blank slate ideology is that they insist all three groups should be on the same track through 20 or so years of school on the way to white collar jobs. But the guy with a strong back and an 85 IQ might be more successful and happier going into a trade at 16, maybe working construction or driving a truck. (I know guys in both fields who make quite good money.) But we can't have that, because everyone's born identical and we're all supposed to get degrees and be doctors and lawyers and community organizers. (So the Mexicans can drive the trucks and build the houses, I guess.)
The test proctor, a Mensa member himself, pointed out that all an IQ test measures is your ability to take IQ tests.
And all a yardstick measures is yards. Yuk yuk. The point is what you can do with that information. Once you know how many yards long something is, you can figure out how long it'll take to run across it, or how much asphalt you'll need to pave it, or whatever. Likewise, IQ tells you how well you can process information and reason things out, which affects all sorts of aspects of life. That quote actually comes from a major IQ researcher (can't remember whom), who certainly wasn't trying to say IQ is worthless. He was pointing out that it only tries to measure intelligence, not all human ability, so complaining that IQ doesn't measure sociability or ambitiousness is like complaining that your yardstick doesn't measure humidity.