When it comes to the vexing topic of women, most scientists and engineers rely heavily on Sigmund Freud and Henry Higgins for inspiration. Dr. Freud's question, "What do women want?!" and Prof. Higgins's lament, "Why can't a woman be more like a man?" pretty much capture the mainstream attitude.

Historically, culturally and economically, science and technology are overwhelmingly male enterprises. Pick a society, any society, and you'll find that women play only the most peripheral roles in shaping the flow of pure science and applied technology. Sure, there's the occasional Madame Curie and Ada, countess of Lovelace, but they're atypical to the point of anomaly.

Current statistics reinforce the historical patterns: Only 6 percent of all working engineers in America today are women. Women probably have greater influence over the future of baseball than they do over emerging technologies.

But wait; it gets worse. Although women represent more than 40 percent of law school enrollment and more than 35 percent of medical school enrollment, barely 14 percent of baccalaureate engineering graduates last year were female -- an astonishingly low figure but positively grandiose compared to the 2.3 percent level of 1975. European and Japanese figures are scarcely better. For all intents and purposes, women have been practically irrelevant to the revolutions that have swept through the physical sciences and sparked the dominant technologies of this era.

There's no question that there are a lot of male chauvinist pigs snuffling among the test tubes. The hard sciences -- notably physics and chemistry -- are notorious for their "old boy" cultures; it's as much "who you know" as "what you know" to get that lucrative post-doctorate fellowship. Deans of engineering colleges piously shrug their shoulders and bleat how difficult it is to graduate top-flight female talent even as they call them "girls." Much of this sexism is open; far more is subtle and subconscious, the result of self-perpetuating traditions that treat women as exceptions to the rule rather than participants who happen to be the other gender.

"For a profession that fancies itself as intellectually neutral, science, like any other part of our life, is heir to all the social realities," says feminist scholar Vivian Gornick, author of "Women in Science."

And yet, can tacit sexism and overt misogyny really explain this overwhelming gender gap? After all, weren't lawyers and doctors once paragons of sexist professional elites? A generation ago, law schools and medical schools -- not to mention business schools -- treated women as less than second-class citizens. That's no longer true. Similarly, women now exert significant influence in political, economic and social circles that were once barred to them. Does anyone out there really believe that a cabal of scientists and engineers could successfully thwart the active participation of women in their domains when lawyers and doctors could not?

Reality indicates that there may be other reasons for this gender gap. The principal of an elite Southern California private girls school that recently went coed acknowledges that, despite the school's best efforts, females are consistently and significantly under-represented in the advanced science classes. "I can't deny that there's a gap," she said, "but I can't really explain why it's there."

This isn't unusual. Girls are rarely equitably represented in elective high school physics, chemistry or calculus classes. Indeed, barely a third of the finalists of the nationwide Westinghouse Science Talent Search are girls -- that's already below their classroom percentage.

Is this because girls have their interest in science squeezed out of them by the time they enter high school? Or is it because, on average, girls are simply less interested in science than in other subjects? There are even respected studies from Johns Hopkins University purporting to show that, discounting social biases, young girls' math skills are, on average, inferior to those of boys. Basically, is this dearth of women in science and technology simply "society's fault"? Or something inherent?

The correct answer is "none of the above." In fact, there are active and exciting domains of science where women are increasingly active on all levels: molecular biology, medical research and biotechnology. According to Dr. Brigid D. Leventhal, director of clinical research administration at Johns Hopkins and a Westinghouse judge for more than 20 years, "girls are more heavily into the biomedical sciences than in the physical sciences."

There's no inherent reason for this except, perhaps, says Leventhal, that "to be in the biological sciences may be less distorting to the female nurturing self-image than the physical sciences or engineering." I am neither bold enough nor foolish enough to assert that this self-image comes about because of acculturation or deeply biological urges that sway individual choice. Is it more socially acceptable for women to be involved in engineering life than engineering silicon chips? I don't know.

What I do know is that, even though organic chemistry is more difficult to master in college than physical chemistry, more women in college take organic chemistry. This issue, I believe, isn't intellect; it's interest. For whatever reasons, women simply aren't as interested in being chemists, physicists and electronics engineers as they are in being doctors, molecular biologists and genetic engineers.

This raises a fascinating question: Does gender matter in scientific research? Do women, because of their interests, temperaments and backgrounds, bring a different sensibility to scientific research than their male counterparts?

Talk with people at Johns Hopkins, Stanford University and Massachusetts Institute of Technology's Whitehead Institute, and it's immediately clear that the influx of women in molecular biology has influenced the nature of research. Women make a difference. According to one lab director, they are more interested in finding patterns than solving problems.

On one level, this shouldn't be surprising; men and women are, of course, different. On another level, it's disturbing; if men and women really are different, one runs into the thorny questions of the strengths and weaknesses associated with those differences. Given current trends, women will continue to rise in importance and influence in life science research. However, unless there are fundamental changes in society and the engineering infrastructure -- such as requiring all high school students to take four years of science and math -- we may never know just what sort of a sensibility women might bring to the various disciplines of engineering.

Michael Schrage is a columnist for the Los Angeles Times.