Charles Murray (The Bell Curve) urges us to move past The Inequality Taboo and to discuss group differences frankly.
For example, he notes some obvious differences between men and women that would explain the achievement gap in many fields:
Regarding women, men, and babies, the technical literature is as unambiguous as everyday experience would lead one to suppose. As a rule, the experience of parenthood is more profoundly life-altering for women than for men. Nor is there anything unique about humans in this regard. Mammalian reproduction generally involves much higher levels of maternal than paternal investment in the raising of children.[18] Among humans, extensive empirical study has demonstrated that women are more attracted to children than are men, respond to them more intensely on an emotional level, and get more and different kinds of satisfactions from nurturing them. Many of these behavioral differences have been linked with biochemical differences between men and women.[19]Thus, for reasons embedded in the biochemistry and neurophysiology of being female, many women with the cognitive skills for achievement at the highest level also have something else they want to do in life: have a baby. In the arts and sciences, forty is the mean age at which peak accomplishment occurs, preceded by years of intense effort mastering the discipline in question.[20] These are precisely the years during which most women must bear children if they are to bear them at all.
Among women who have become mothers, the possibilities for high-level accomplishment in the arts and sciences shrink because, for innate reasons, the distractions of parenthood are greater. To put it in a way that most readers with children will recognize, a father can go to work and forget about his children for the whole day. Hardly any mother can do this, no matter how good her day-care arrangement or full-time nanny may be. My point is not that women must choose between a career and children, but that accomplishment at the extremes commonly comes from a single-minded focus that leaves no room for anything but the task at hand.[21] We should not be surprised or dismayed to find that motherhood reduces the proportion of highly talented young women who are willing to make that tradeoff.
Some numbers can be put to this observation through a study of nearly 2,000 men and women who were identified as extraordinarily talented in math at age thirteen and were followed up 20 years later.[22] The women in the sample came of age in the 1970′s and early 1980′s, when women were actively socialized to resist gender stereotypes. In many ways, these talented women did resist. By their early thirties, both the men and women had become exceptional achievers, receiving advanced degrees in roughly equal proportions. Only about 15 percent of the women were full-time housewives. Among the women, those who did and those who did not have children were equally satisfied with their careers.
And yet. The women with careers were four-and-a-half times more likely than men to say they preferred to work fewer than 40 hours per week. The men placed greater importance on “being successful in my line of work” and “inventing or creating something that will have an impact,” while the women found greater value in “having strong friendships,” “living close to parents and relatives,” and “having a meaningful spiritual life.” As the authors concluded, “these men and women appear to have constructed satisfying and meaningful lives that took somewhat different forms.”[23] The different forms, which directly influence the likelihood that men will dominate at the extreme levels of achievement, are consistent with a constellation of differences between men and women that have biological roots.
I have omitted perhaps the most obvious reason why men and women differ at the highest levels of accomplishment: men take more risks, are more competitive, and are more aggressive than women.[24] The word “testosterone” may come to mind, and appropriately. Much technical literature documents the hormonal basis of personality differences that bear on sex differences in extreme and venturesome effort, and hence in extremes of accomplishment–and that bear as well on the male propensity to produce an overwhelming proportion of the world’s crime and approximately 100 percent of its wars. But this is just one more of the ways in which science is demonstrating that men and women are really and truly different, a fact so obvious that only intellectuals could ever have thought otherwise.