Poor people have I.Q.'s significantly lower than those of rich people, and the awkward conventional wisdom has been that this is in large part a function of genetics.
After all, a series of studies seemed to indicate that I.Q. is largely inherited. Identical twins raised apart, for example, have I.Q.'s that are remarkably similar. They are even closer on average than those of fraternal twins who grow up together.
If intelligence were deeply encoded in our genes, that would lead to the depressing conclusion that neither schooling nor antipoverty programs can accomplish much. Yet while this view of I.Q. as overwhelmingly inherited has been widely held, the evidence is growing that it is, at a practical level, profoundly wrong. Richard Nisbett, a professor of psychology at the University of Michigan, has just demolished this view in a superb new book, "Intelligence and How to Get It," which also offers terrific advice for addressing poverty and inequality in America.