As the saying goes, behind every successful woman is a man who is surprised. Harvard president Larry Summers apparently is that man. A distinguished economist who was Treasury Secretary under Clinton, Summers caused a firestorm on January 14 when, speaking from notes at a conference on academic diversity, he argued that tenured women are rare in math and science for three reasons, which he listed in descending order of importance. One, women choose family commitments over the eighty-hour weeks achievement in those fields requires; two, fewer women than men have the necessary genetic gifts; and three, women are discriminated against. Following standard economic theory, Summers largely discounted discrimination: A first-rate woman rejected by one university would surely be snapped up by a rival. We're back to women's lack of commitment and brainpower.

On campus, Summers has lost big--he has had to apologize, appoint a committee and endure many a hairy eyeball from the faculty, and complaints from furious alumnae like me. In the press, he's done much better: Provocative thinker brought down by PC feminist mob! Women are dumber! Steven Pinker says so! The New York Times even ran a supportive op-ed by Charles Murray without identifying him as the co-author of The Bell Curve, the discredited farrago of racist claptrap. While much was made of MIT biologist Nancy Hopkins walking out of his talk--what about free speech, what about Truth?--we heard little about how Summers, who says he only wanted to spark a discussion, has refused to release his remarks. The bold challenger of campus orthodoxy apparently doesn't want the world to know what he actually said.

Do men have an innate edge in math and science? Perhaps someday we will live in a world free of the gender bias and stereotyping we know exists today both in and out of the classroom, and we will be able to answer that question, if anyone is still asking it. But we know we don't live in a bias-free world now: Girls are steered away from math and science from the moment they are born. The interesting fact is that, thanks partly to antidiscrimination laws that have forced open closed doors, they have steadily increased their performance nonetheless. Most of my Radcliffe classmates remember being firmly discouraged from anything to do with numbers or labs; one was flatly told that women couldn't be physicians--at her Harvard med school interview. Today women obtain 48 percent of BAs in math, 57 percent in biology and agricultural science, half of all places in med school, and they are steadily increasing their numbers as finalists in the Intel high school science contest (fifteen out of forty this year, and three out of four in New York City).

Every gain women have made in the past 200 years has been in the face of experts insisting they couldn't do it and didn't really want to. Biology, now trotted out to "prove" women's incapacity for math and science, used to "prove" that they shouldn't go to college at all. As women progress, the proponents of innate inferiority simply adapt their arguments to explain why further advancement is unlikely. But how can we know that in 2005, any more than we knew it in 1905? I'd like to hear those experts explain this instead: The number of tenure offers to women at Harvard has gone down in each of Summers's three years as president, from nine in thirty-six tenures to three in thirty-two. (The year before his arrival, it was thirteen women out of thirty-six.) Surely women's genes have not deteriorated since 2001?

Whatever they may be in theory, in the workplace, biological incapacity and natural preference are the counters used to defend against accusations of discrimination. Summers argues that competition makes discrimination irrational; that wouldn't hold, though, if an entire field is pervaded with discrimination, if there's a consensus that women don't belong there and if female candidates are judged more harshly by all potential employers. It also doesn't work if the threat of competition isn't so credible: It will be a long time before the Ivies feel the heat from Northwestern, which has improved its profile by hiring the first-rate women they foolishly let go. The history of women and minorities in the workplace shows that vigorous enforcement of antidiscrimination law is what drives progress. Moreover, the competition argument can be turned against Summers: After all, given its prestige and wealth, Harvard could "compete" for women with any university on the planet. So why doesn't it?

This brings us to that eighty-hour week and women's domestic "choices." It's a truism that career ladders are based on the traditional male life plan--he knocks himself out in his 20s and 30s while his wife raises the kids, mends his socks and types his papers. If women had been included from the start, the ladder would look rather different--careers might peak later, taking a semester off to have a baby would not blot your copybook, women would not be expected to do huge amounts of academic service work and then be blamed at tenure time for not publishing more. By treating this work culture as fixed, and women as the problem, Summers lets academia off the hook. Yet Harvard, with its $23 billion endowment, doesn't even offer free daycare to grad students.

There's a ton of research on all the subjects raised by Summers--the socialization of girls; conscious and unconscious gender bias in teaching, hiring and promotion; what makes talented females, like Intel finalists, drop out of science at every stage; what makes motherhood so hard to combine with a career. We are past the day when brilliant women could be expected to sit quietly while a powerful man parades his ignorance of that scholarship and of their experience. It is not "provocative" when the president of Harvard justifies his university's lamentable record by recalling that his toddler daughter treated toy trucks like dolls. It's an insult to his audience. What was his point, anyway? That she'll grow up and flunk calculus? That she'll get a job in a daycare center?

If Summers wants to know why women are underrepresented in math and science, he should do his homework, beginning with Nancy Hopkins's pathbreaking 1999 study of bias against female faculty at MIT. And then he should ask them.

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