> Barres said the switch had given him access to conversations that

> would have excluded him previously: "I had a conversation with a male

> surgeon and he told me he had never met a woman surgeon who was as

> good as a man."

>

> Barres's salvo, bolstered with scientific studies, marks a dramatic

> twist in a controversy that began with Summers's suggestion last year

> that "intrinsic aptitude" may explain why there are relatively few

> tenured female scientists at Harvard. After a lengthy feud with the

> Faculty of Arts and Sciences, Summers resigned earlier this year.

>

> The episode triggered a fierce fight between those who say talk of

> intrinsic differences reflects sexism that has held women back and

> those who argue that political correctness is keeping scientists from

> frankly discussing the issue.

>

> While there are men and women on both sides of the argument, the

> debate has exposed fissures along gender lines, which is what makes

> Barres so unusual.

> Barres said he has realized from personal experience that many men are

> unconscious of the privileges that come with being male, which leaves

> them unable to countenance talk of glass ceilings and discrimination.

>

> Barres's commentary was published yesterday in the journal Nature. The

> scientist has also recently taken his argument to the highest reaches

> of American science, crusading to make access to prestigious awards

> more equitable.

>

> In an interview, Nancy Andreasen, a well-known psychiatrist at the

> University of Iowa, agreed with Barres. She said it took her a long

> time to convince her husband that he got more respect when he

> approached an airline ticket counter than she did. When she stopped

> sending out research articles under her full name and used the

> initials N.C. Andreasen instead, she said, the acceptance rate of her

> publications soared.

>

> Andreasen, one of the comparatively few women who have won the

> National Medal of Science, said she is still regularly reminded she is female.

> "Often, I will be standing in a group of men, and another person will

> come up and say hello to all the men and just will not see me, because

> in a professional setting, men are not programmed to see women," she said.

> "Finally, one of the men will say, 'I guess you haven't met Nancy

> Andreasen,' and then the person will turn bright red and say, 'Oh

> Nancy, nice to see you!' "

>

> Summers did not respond to a request for an interview. But two

> scientists Barres lambasted along with Summers said the Stanford

> neurobiologist had misrepresented their views and unfairly tarred

> those who disagree with crude assertions of racism and sexism. Harvard

> cognitive scientist Steven Pinker and Peter Lawrence, a biologist at

> Britain's Laboratory of Molecular Biology in Cambridge, said

> convincing data show there are differences between men and women in a

> host of mental abilities.

>

> While bias could be a factor in why there were fewer women at the

> pinnacles of science, both argued that this was not a primary factor.

>

> Pinker, who said he is a feminist, said experiments have shown, on

> average, that women are better than men at mathematical calculation

> and verbal fluency, and that men are better at spatial visualization

> and mathematical reasoning. It is hardly surprising, he said, that in

> his own field of language development, the number of women outstrips

> men, while in mechanical engineering, there are far more men.

>

> "Is it essential to women's progress that women be indistinguishable

> from men?" he asked. "It confuses the issue of fairness with sameness.

> Let's say the data shows sex differences. Does it become okay to

> discriminate against women? The moral issue of treating individuals

> fairly should be kept separate from the empirical issues."

>

> Lawrence said it is a "utopian" idea that "one fine day, there will be

> an equal number of men and women in all jobs, including those in

> scientific research."

>

> He said a range of cognitive differences could partly account for

> stark disparities, such as at his own institute, which has 56 male and

> six female scientists. But even as he played down the role of sexism,

> Lawrence said the "rat race" in science is skewed in favor of pushy,

> aggressive people -- most of whom, he said, happen to be men.

>

> "We should try and look for the qualities we actually need," he said.

> "I believe if we did, that we would choose more women and more gentle

> men. It is gentle people of all sorts who are discriminated against in

> our struggle to survive."

>

> Barres and Elizabeth Spelke, a Harvard psychologist who has publicly

> debated Pinker on the issue, say they have little trouble with the

> idea that there are differences between the sexes, although some

> differences, especially among children, involve biases among adults in

> interpreting the same behavior in boys and girls.

>

> And both argue it is difficult to tease apart nature from nurture.

> "Does anyone doubt if you study harder you will do better on a test?"

> Barres asked. "The mere existence of an IQ difference does not say it is innate.

> .

> . . Why do Asian girls do better on math tests than American boys? No

> one thinks they are innately better."

>

> In her debate with Pinker last year, Spelke said arguments about

> innate differences as explanations for disparities become absurd if

> applied to previous eras. "You won't see a Chinese face or an Indian

> face in 19th-century science," she said. "It would have been tempting

> to apply this same pattern of statistical reasoning and say, there

> must be something about European genes that give rise to greater

> mathematical talent than Asian genes."

>

> "I think we want to step back and ask, why is it that almost all Nobel

> Prize winners are men today?" she concluded. "The answer to that

> question may be the same reason why all the great scientists in

> Florence were Christian."