In the mosaic of America, three groups -- Asian-Americans, Jews and West Indian blacks -- have been unusually successful, and in that there may be some lessons for the rest of us.
Asian-Americans are renowned for ruining grade curves in schools across the land, and they constitute about 20 percent of students at Harvard College.
Jews have received about one-third of all Nobel Prizes in science received by Americans. One survey found that a quarter of Jewish adults in the United States have earned a graduate degree, compared with 6 percent of the population as a whole.
West Indian blacks, those like Colin Powell whose roots are in the Caribbean, are one-third more likely to graduate from college than African-Americans as a whole, and their median household income is almost one-third higher.
These three groups may help debunk the myth of success as a simple product of intrinsic intellect, for they represent three different races and histories. In the debate over nature and nurture, they suggest the importance of improved nurture -- which, from a public policy perspective, means a focus on education.
Richard Nisbett cites each of these groups in his superb book "Intelligence and How to Get It." Nisbett, a professor of psychology at the University of Michigan, argues that what we think of as intelligence is quite malleable and owes little or nothing to genetics.
"I think the evidence is very good that there is no genetic contribution to the black-white difference on IQ," he said, adding that there also seems to be no genetic difference in intelligence between whites and Asians.
He says the evidence is overwhelming that what is distinctive about these three groups is not innate advantage but rather a tendency to get the most out of the firepower they have.
One large study followed a group of Chinese-Americans who initially did slightly worse on the verbal portion of IQ tests than other Americans and the same on math portions. But beginning in grade school, the Chinese outperformed their peers, apparently because they worked harder.
As adults, 55 percent of the Chinese-American sample entered high-status occupations, compared with one-third of whites.
A common thread among these three groups may be an emphasis on diligence or education, perhaps linked in part to an immigrant drive. Jews and Chinese have a particularly strong tradition of respect for scholarship, with Jews said to have achieved complete adult male literacy -- the better to read the Talmud -- some 1,700 years before any other group.
The parallel force in China was Confucianism and its reverence for education. You can still sometimes see in rural China the remains of a monument to a villager who triumphed in the imperial exams. In contrast, if an American town has someone who earns a Ph.D., the impulse is not to build a monument but to pass a hat.
Among West Indians, the crucial factors for success seem twofold: the classic diligence and hard work associated with immigrants, and intact families. The upshot is higher family incomes and fathers more involved in child-rearing.
What's the policy lesson from these three success stories? It's that the most decisive weapons in the war on poverty aren't transfer payments but education, education, education. For at-risk households, that starts with social workers making visits to encourage such basic practices as talking to children. One study found that a child of professionals (disproportionately white) has heard about 30 million words spoken by age 3; a black child raised on welfare has heard only 10 million words, leaving that child at a disadvantage in school.
The next step is intensive early childhood programs, followed by improved elementary and high schools, and programs to defray college costs.
Perhaps the larger lesson is a very empowering one: Success depends less on intellectual endowment than on perseverance and drive.
THE NEW YORK TIMES