This belongs on the main page rather than in the comments section:
"I'll concede IQ tests whatever it is they test. That is to say, whatever it is they test is not completely coincident with Intelligence with a capital "I." But whatever it is they test is quite important because it predicts for a variety of phenomena that human beings are concerned about like (1) ability to succeed in education (2) ability to suceed in business (3) criminal tendencies (4) accident tendencies (4) ability to solve problems in general and (5) socialization.
Smart parents raise smart kids, no doubt. But kids of "smart" parents raised in foster homes, adoptive homes, etc. also tend to be smart as we know from twin and adoption studies. Or dumb as the case may be, as in the case of dumb kids from antisocial low IQ parents rasised in high socioeconomic status pro-education homes.
But I suppose we could bury our heads in the sand, not read any of the relevant literature, and pretend that IQ is not highly heritable based on genetics. Your arguing is like Ptolemaic astronomy. Even though the best and simplest explanation is genetics, our PC culture compels you to come up with less likely, less plausible, and less predictive explanations. Meanwhile, surprise surprise, low IQ toddlers become low IQ HS students become low IQ adults who have low IQ kids and we have intergenerational poverty which is quite puzzling to the everything-is-envrionement crowd."
In my view, the tests accounting for adoption and twins separated from one another in significantly different environments are compelling.
Also, for those of you who get it and accept that a good degree of hereditable intelligence has been proved, you may find it interesting to note that a son's intelligence tends to be determined by his mother's genes.