I don't think anybody would seriously dispute that relationship. Rather, I think people are disputing the directionality.
You seem to be suggesting some sort of natural selection process, whereas it's also legitimate to posit that status contributes to higher IQ (or g, if you prefer) in the form of:
- fewer chemical contaminants in utero and in early life (i.e. living in a less chemically polluted environment)
- access to better nutrition
- access to better medical care
- less stress in utero and in early life
- less exposure to disease
- less exposure to psycho-physiological toxicity (e.g.: poor sleep quality due to a noisy environment)
The list goes on.
tl;dr: you're assuming causation from correlation.
The average American has more wealth than pretty much everyone on Earth. You can't seriously think that it's because Americans are all genetically smarter than everyone else?
Variation within a group can be explained by different factors than variation between groups. That is, it could be completely true that Americans with higher IQs are more likely to become wealthy. But as a group America's success is due to other factors than IQ.
Just to be clear - I'm comparing two billionaires who started off as millionaires, and suggesting that Gates is of above average intelligence whereas Trump is not.
But it doesn't last long. After 3 generations, maybe less, there's little statistical difference between those descended from wealth and those not (all else equal!) The super wealthy may leave billion dollar empires to their children, sure. But if we are talking about the upper middle class, a moderate inheritance from your parents isn't going to make or break your life's outcome.
A moderate inheritance plus support during your education may well make or break your life's outcome vs someone born to a poor family.
'Inheritance' doesn't have to mean just what was passed down at death - it must also include all the additional resources available during development to have any meaning.
But it doesn't! That's the point. Otherwise the lottery winners kids would be better off since they could go to better schools and afford college. In general there's little evidence that education makes any difference at all.
Seriously, your lottery winners example is meaningless.
But if you are saying that education makes little difference to lifetime earnings, you're going to have to back that up with a reference because it's an extraordinary claim.
The result isn't necessarily surprising, but it does show a point. Not all lottery winners blow the money immediately and foolishly. You would expect there to be at least some statistical effect. But it doesn't seem to matter. And it's probably the best randomized experiment we can do to compare the effects of wealth and not wealth, all other variables equal. Wealth doesn't' seem to matter as much as people think it does.
It goes back in time too. Winners of 1832 Georgia land lottery were given free land of significant value by the government to settle and farm. After a few decades, they weren't any better off than the nonwinners.
