In post #81 you tried to refute my point by using examples of extreme wealth, which is not the point I was making at all. Let me rephrase:
- Intelligent people have more employment opportunities, some of which can provide considerable money. To be clear, I think it's commendable when a highly intelligent person decides to take a lower paying job they love, such as a schoolteacher or an academic. But many will choose higher paying positions such as medicine, finance, software engineering, etc. As a result, income skews higher with intelligence. This correlation is fairly low (estimates I have seen are around 0.3), but it's clearly there.
- Intelligence is significantly heritable, similar to how height, good looks, or athletic talent is heritable. This makes some people uncomfortable, but it's reality. And I grant that environment affects how well these genetic capabilities become realized. A person with the genes to become tall can have stunted growth due to poor nutrition. Likewise a person with the genes to become intelligent can suffer in a home that doesn't provide mental stimulation. This requires a certain baseline level of income and parental involvement, but beyond that there are only marginal effects .
- Given the two effects above, you are very likely to end up with a scenario that shows that test scores correlate to parental income. In fact, I would be hard pressed to come up with general scenarios where this is not true (corner cases are easy enough to find however). But note the causal relationship is not the parental income, but the intelligence that is tied to both.