Why So Few Women Supreme Court Clerks?

Amber (Prettier than Napoleon) asks the question, and it's a very interesting one.

Is the cause possible differences in innate intelligence at the tail ends of the bell curve (what I'd heard called the idiot-genius syndrome, which leads men to be overrepresented both among the very low-IQ and the very high-IQ)? Sex discrimination in law school classes (whether on the exam or before) or in hiring? Social pressures that push some women away from law school? Differences in innate ambition? Social pressures that lead men to be more ambitious than women (for instance, because less ambitious men face more condemnation from parents, peers, or prospective girlfriends than do less ambitious women, or because more ambitious women face more such condemnation than more ambitious men)? The tendency of women to marry at a somewhat younger age than men, coupled with a tendency of married people to on average be less likely than single people to move? (Moving is often needed to get the prestigious appellate clerkship that can help lead to a Supreme Court clerkship.) The greater tendency of women than men to have spouses or lovers who aren't easily movable, which may again make it less likely that women would move to get the prestigious appellate clerkship? A combination of some or all of the above?

I'd love to hear speculation, but even more I'd love to hear actual data.

UPDATE: By the way, some data, from my year clerking (1993-94): Of the 38 clerks (including 4 who were clerking for retired Justices), 11 were women. As I recall, 5 of the 11 women were married, none had children, and at least 4 of the married women had left their husbands in a different city.

Of the 27 men, only 5 were married, 5 had children (including one who was divorced and whom I didn't include in the 5), and 4 of the married men's wives were with them in D.C.

This is just one year, and any serious study would have to look at much more than one year. But it led me to wonder whether the women who had the law school credentials to get the prestigious but often out-of-town appellate clerkships that are stepping-stones to the Supreme Court

1. might be more likely to be married than comparable men (presumably because women marry slightly younger than men),
2. might have more difficulty getting their husbands to move with them than men would have getting their wives to move with them (perhaps because the women's spouses are more likely to have hard-to-move jobs than the men's spouses), and
3. might have more difficulty clerking, especially in a highly demanding clerkship, if they have children than comparable men would.

If the answers to some of these questions are yes, then this might lead some of these women to drop out of the clerkship race, likely by not looking for a prestigious out-of-town appellate clerkship.

More on Sex and Supreme Court Clerks:

Ann Althouse (whose work I generally very much like) bristles at one of the several candidate explanations I included in my earlier post:

Eugene Volokh asks why are there so many more male Supreme Court clerks than female? His first guess is:

Is the cause possible differences in innate intelligence at the tail ends of the bell curve (what I'd heard called the idiot-genius syndrome, which leads men to be overrepresented both among the very low-IQ and the very high-IQ)?

Oh, please. I know it's in question form, but really...

Perhaps I misunderstand Ann's reason for the "Oh, please." Still, I'd have thought that when one is seeking the causes of disparities such as this, the possibility of men's biologically caused overrepresentation at the tail ends of the IQ bell curve must be one candidate explanation that one should consider. Even if the effect is relatively small, too small to explain by itself a 2.5 to 1 disparity (just to use as an example the disparity the year I clerked), it may still be important as one of the explanations: Five causes, each of which would cause an extra 1.2 to 1 disparity, can multiply out to 2.5 to 1. And I'd think that any analysis that infers some cause -- or estimates the magnitude of some cause -- from the disparity but fails to consider this other possible cause would itself be unsound.

Of course this potential explanation might ultimately prove to be entirely unsound -- but is there really any a priori reason why we should dismiss it as implausible? Has scientific research, for instance, conclusively dismissed this possibility? I'd be delighted if people who (unlike me) have actually seriously studied sex-based cognitive differences (or the absence of such differences) could speak to that.

(I should note that my listing the possibility of intelligence differences first wasn't meant to suggest that I think this is likely the most important factor, just as my listing the possibility of sex discrimination second wasn't meant to suggest that I think it was the second most important factor. I really don't know which if any of the factors are important, or how important they are.)

Gender and Science:

A reader kindly pointed me to a couple of interesting items on a matter related to something we touched on a few weeks ago: whether there are material biological cognitive factors that lead men and women to be disproportionately represented in certain fields. (Note that the question isn't whether these are the only factors, or where any particular woman or man falls within the distribution of certain cognitive skills.) The posts on this blog were about law, where matters may be quite different from science. Still, the debate about gender and science is interesting in its own right, and likely overlaps in some measure (though of course not entirely, given that much of the scientific debate is about mathematical aptitude, something that lawyers of both genders are infamous for not having) with similar debates about law.

The reader's two sources were:

1. Edge.org has a debate between Harvard psychology professors Steven Pinker and Elizabeth Spelke.

2. Nature has an article by Stanford neurobiology Prof. Ben Barres, taking the view (as best I can tell) that there are no such material biological differences, and that the entirety of the disparity between men and women in the sciences comes from societal factors. (This is not completely clear, since his introduction frames the issue as being between the "Larry Summers Hypothesis" "that women are not advancing because of innate inability rather than because of bias or other factors," and the rival hypothesis that "women are not advancing because of discrimination." But since Larry Summers' point was that part of the reason for the disparate representation of women is biological cognitive differences, I take Barres' rejection of the "Larry Summers Hypothesis," and specific criticism of Summers, to mean that he's saying that biological differences are no part or perhaps next to no part of the matter.)

I'll have a bit to say shortly about details in the Barres source, but for now I just wanted to post the links.

Be Careful Trusting Data, Even in Nature:

I found Ben Barres' Nature article, "Does Gender Matter?", to be very interesting; and one thing that quite struck me was this assertion: "[D]espite all the social forces that hold women back from an early age, one-third of the winners of the elite Putnam Math Competition last year were women." Perhaps I overestimated the importance of this assertion because I'm actually familiar with the Putnam Competition (I never participated, and I'm not nearly good enough at math to get anywhere near top scores on it, but I occasionally look at some old problems and enjoy taking a whack at them). Still, the competition seems to test creative math ability and not just rote application of rules, and to test high-end ability: The "does gender matter?" debate in science faculty hiring, after all, has to do with claimed differences between the very far right tails of the male and female math ability bell curves, not between the average man and the average woman or even the average male and female college students.

So, I thought, if one-third of the winners — basically, of the top 15 or so finishers — of the competition are women, despite the social pressures that I'm quite sure would drive down the number of successful women, that really is a powerful data point. (Recall that the question generally isn't whether the disproportionate representation of men and women in high-end science jobs is due entirely to biology, but only whether it's due partly to biology.)

Unfortunately, when I looked more closely at this data point, it turned out to be in error. Here's what I submitted as a letter to the editors of Nature:

Dear Editors:

I read with interest Ben Barres' "Does gender matter?" (13 July 2006), and particularly the statement that "one-third of the winners of the elite Putnam Math Competition last year were women." This struck me as a particularly telling piece of evidence: If indeed so many women performed so well in such a respected competition, this would indeed undermine assertions of substantial biological gender differences in the higher levels of mathematical ability.

Unfortunately, on further research, it seems that this statement is mistaken. Last year's (2005's) top 16 finishers seem to have included only one woman (UNL 2005). Prof. Barres was likely referring to 2004, but even in that year the top 15 included only four women (Hopkins 2005; UNL 2004). In 2003, two of the top 16 were women (UNL 2003; Princeton 2006). In 2002 and 2001, the number was one of 15. Perhaps I'm mistaken, despite my attempts to verify the ambiguous names; but this is the data as best I can determine it.

Prof. Barres' other claims in the article may well be accurate; the data I cite above certainly don't prove that the reason for the low numbers is even partly biological sex differences. On the other hand, I thought it might be helpful to let readers know that one particular piece of evidence mentioned in the article seems mistaken.

Eugene Volokh
Professor
UCLA School of Law

Sources: Hopkins, Nancy, 2005. "Academic Responsibility and Gender Bias," XVII MIT Faculty Newsletter No. 4, pp. 1, 24.
UNL Web site, 2005. "The William Lowell Putnam Mathematical Competition, Announcement of Winners ...."
     2004. http://www.unl.edu/amc/a-activities/a7-problems/putnam/-html/putnam2004results.html.
     2003. http://www.unl.edu/amc/a-activities/a7-problems/putnam/-html/putnam2003results.html.
     2002. http://www.unl.edu/amc/a-activities/a7-problems/putnam/-html/putnam2002results.html.
     2001. http://www.unl.edu/amc/a-activities/a7-problems/putnam/-html/putnam2001results.html.
Princeton, 2006. Telephone Conversation with Mathematics Department at Princeton University, July 19, 2006.

Unfortunately, Nature has decided not to publish the letter; here's their response:

Dear Professor Volokh

Thank you for your letter. We have checked into the figures and it seems that in 2004 four of the fifteen top ranked Putnam winners were women (one other might have been, we can't tell). Although we agree that it is unfortunate that we did not include the year in the relevant sentence in the commentary, we feel that 4 (probably, but maybe 5) out of 15 is sufficiently close to one-third not to publish a correction on this occasion.

Thank you again for writing to us.

Perhaps it's me, but it seems to me that the response is missing my point — not only was the number 5 likely wrong (as Prof. Nancy Hopkins' article agrees), and not only was the year wrong (not just omitted, but wrong, since the story unambiguously says "last year"), but the data that Prof. Barres cites is highly unrepresentative, and its unrepresentativeness is hidden by the omission of the year.

If you see "last year the results were X," that might suggest to you that the results in previous years were similar but only the last year was mentioned because it's the closest data point; or it might suggest to you that in any event the trend is towards last year's X. But if you see "in 2004, the results were X," you'd be much likelier to quickly recognize that maybe the 2005 results were different. And given how different the results are — in reverse chronological order, they seem to be 1, 4, 2, 1, 1 — is it quite right to solely cite the 4 (even setting aside the dispute about whether it's 4 or 5); to suggest that it's the most recent result; and to omit the four data points, one of them a more recent one, that would suggest a very different situation?

Two notes. First, I corresponded with Prof. Barres when trying to track all this down, and he was quite gracious about it. I'm sure his error was entirely innocent; I just wish the Nature editors were willing to correct it. Second, I should stress that the aggregate data does not prove that biology is the reason for disparity; cultural factors may well account for the entire gulf even so. My point is simply that one of the reasons to believe that the biological factors are absent or slight — much closer to par representation of men and women on the Putnam exam — appears not to be correct.

And, more broadly, as the title suggests, don't trust everything you read — even relatively easily verifiable data in a respect journal such as Nature.

Should Speech About Gender Cognitive Differences "Not Be Tolerated" on Campus, and Instead Treated as "Verbal Violence" Rather Than "Free Speech"?

I blogged yesterday about Stanford neurobiology professor Ben Barres' article in Nature; I thought his argument was quite interesting, and may be generally quite right as a scientific matter (my correction was only focused on one error, which may not affect the bottom line). Yet the following passage from the article troubles me (emphasis added):

Steven Pinker has responded to critics of the Larry Summers Hypothesis by suggesting that they are angry because they feel the idea that women are innately inferior is so dangerous that it is sinful even to think about it. Harvard Law School professor Alan Dershowitz sympathizes so strongly with this view that he plans to teach a course next year called 'Taboo'. At Harvard we must have veritas; all ideas are fair game. I completely agree. I welcome any future studies that will provide a better understanding of why women and minorities are not advancing at the expected rate in science and so many other professions.

But it is not the idea alone that has sparked anger. Disadvantaged people are wondering why privileged people are brushing the truth under the carpet. If a famous scientist or a president of a prestigious university is going to pronounce in public that women are likely to be innately inferior, would it be too much to ask that they be aware of the relevant data? It would seem that just as the bar goes way up for women applicants in academic selection processes, it goes way down when men are evaluating the evidence for why women are not advancing in science. That is why women are angry. It is incumbent upon those proclaiming gender differences in abilities to rigorously address whether suspected differences are real before suggesting that a whole group of people is innately wired to fail.

What happens at Harvard and other universities serves as a model for many other institutions, so it would be good to get it right. To anyone who is upset at the thought that free speech is not fully protected on university campuses, I would like to ask, as did third-year Harvard Law student Tammy Pettinato: what is the difference between a faculty member calling their African-American students lazy and one pronouncing that women are innately inferior? Some have suggested that those who are angry at Larry Summers' comments should simply fight words with more words (hence this essay). In my view, when faculty tell their students that they are innately inferior based on race, religion, gender or sexual orientation, they are crossing a line that should not be crossed — the line that divides free speech from verbal violence — and it should not be tolerated at Harvard or anywhere else. In a culture where women's abilities are not respected, women cannot effectively learn, advance, lead or participate in society in a fulfilling way.

As best I can tell, Prof. Barres is arguing that those like Larry Summers who believe that the disparate representation of men and women in certain fields flows partly from biological cognitive differences ought not be allowed to express their views, at least at the university. Such speech, he argues, is not "free speech" but instead "verbal violence" and "should not be tolerated at Harvard or anywhere else." What's more, he seems to be distancing himself from the view that this lack of "tolerat[ion]" should extend only to counterargument (though he himself engages in this): This view, he says, is what "Some have suggested," while "In [Barres'] view," statements like Summers' should not be tolerated and should instead be treated like verbal violence (and violence is usually fought through tools other than counterspeech) rather than speech.

This strikes me as an extremely troubling proposition. Prof. Barres may have the better of the scientific argument — but here he seems to be suggesting that we shut down the scientific argument, by refusing to "tolerate[]" or treat as "free speech" contrary views. This (1) risks suppressing true counterarguments to Prof. Barres' views, if it turns out that Prof. Barres' is mistaken (at least in part).

It also (2) undermines the credibility of Prof. Barres' own views, even if they're completely correct. As a layperson, I don't know who's right on this debate. Prof. Barres may be sure based on his own extensive research, but naturally most of the rest of us — including the rest of the colleagues who are deciding whether to condemn statements like Prof. Summers' and "not [to] tolerate[]" such statements in the future — can't be.

If after decades of open and tolerant discussion Prof. Barres' view emerges as the dominant one, laypeople like us can have considerable confidence in its accuracy. (This is why, despite our general openmindedness, we would indeed have little social and professional tolerance for someone who urges the phlogiston theory of fire or something that's been similarly broadly discredited.) If, however, we know that Prof. Barres' view prevailed but only in a debate in which rival views were not tolerated, and were punished as "verbal violence" rather than protected as "free speech," then we can have no confidence in the view's accuracy. For all we know, the view may be largely wrong, and contradicted by important data, but that data has been hidden from us by speech codes or by scientific peer pressure.

Of course, Prof. Barres' position (3) would also set a tremendously dangerous precedent for other fields. Prof. Barres seems to also argue that academics shouldn't be allowed to argue about whether there are important innate racial differences, or innate sexual orientation differences. Apparently one can investigate and debate whether sexual orientation is partly or largely genetically caused, I take it, but not whether it may be correlated with other genetic traits. There'd also be some unclear limits on criticism of religion: Literally his argument is only that faculty may not be allowed to tell their students (or presumably give speeches, such as Summers', that students may hear about) "that they are innately inferior based on ... religion," and it's not clear what innate inferiority based on religion might be (though I have seen discussion of whether a tendency towards religiosity might indeed be genetically linked). But the logic of his argument would suggest that harsh criticisms of certain religious ideological systems that may make adherents of those systems feel unwelcome would also be prohibitable. And those are just Prof. Barres' specific examples; the same arguments could apply to suppressing a wide range of supposedly dangerous academic viewpoints.

Now I understand part of people's concern about discussion of innate gender differences: If certain students get alienated or dispirited enough by such statements, for instance because they're insulted by them or because they wrongly infer that such assertions about broad populations mean that they themselves have no future in some field, they may stay away from certain fields, or certain universities. I do think there are social factors that push many girls and women away from science and engineering, and I think those factors are costly for universities and for society as a whole. Universities and other institutions should work hard to diminish these factors, and to encourage people with mathematical and scientific aptitude — boys and girls alike — to go into math and science (plus encourage people without such aptitude to nonetheless get some decent grasp of the basics).

Such efforts on the part of university, however, should not come at the expense of constraining academic debate about very important scientific issues such as the interaction of gender and cognition. If some students are offended by scientific theories faculty propose, they should be taught to respond with research, analysis, and (if the theories are wrong as well as offensive) rebuttal, not alienation. If some students are dispirited by the implications of those theories, they should be taught to understand the limits of those implications. If some students are concerned about sex discrimination both in society and in their institutions, they should certainly fight it (including by researching the matter, and seeing to what extent any observed disparities flow from discrimination, and to what extent, if any, they may flow from genuine biological differences).

But students should never be taught that apparently dangerous ideas about what is true ought to be fought through suppression, rather than investigation and (when called for) rebuttal. And that brings us to one other problem with Prof. Barres' proposal: (4) It would teach the next generation of scientists the wrong approach to science — an approach that urges them to premature certainty rather than constant doubt and inquiry, and an approach that urges them to suppress contrary views rather than rebut them. That's a poor service to all students, whether male or female.

Scientific Debate, Proof, and Conjecture:

Some commenters to my earlier post reason:

It [presumably discussion of possible innate gender differences in cognition] shouldn't be suppressed for political reasons. I think that a scientific issue, though, shouldn't be taught if there's not good scientific evidence for it. And I haven't seen good scientific evidence for this theory

I think the words "without proof" are implied from the second paragraph.

I.E. "when faculty tell their students that they are innately inferior, without proof, based on race, religion, gender or sexual orientation, they are crossing a line that should not be crossed"

I can see that as being fair.

Yet not every step in the scientific process can (or should) contain "proof" in any strong sense of the word. Scientific debates often present conjectures based on ambiguous evidence. The conjectures lead to responses, often equally conjectural. Evidence on one side or the other grows or shrinks. We often get something approaching "proof" only after decades of unproven conjectures have led to more evidence-gathering and more discussion.

This is especially so in areas (including biology and social science) where the evidence tends to be suggestive, not dispositive, and confounding factors are always potentially present. Even in math, though, where "proof" is indeed the touchstone, unproven conjectures are often made. If you couldn't say anything without "proof," whether logical proof, proof beyond a reasonable doubt, or even proof by a preponderance of the evidence as determined by some campus committee, scientific debate would be much curtailed.

I agree with Frank that professors who are teaching classes shouldn't teach as true statements that haven't been adequately proven. But Summers wasn't teaching a class, nor did he assert his claims as having been proven true. If professors can't express such conjectures — yet presumably their rivals would be quite free to present contrary conjectures, unless we're to completely eliminate public conjecture in science — then what sort of debate would we have?

Now perhaps conjectures that are entirely unbacked by any evidence, or backed by asserted evidence or reasoning that has been conclusively disproven through decades of open debate, are sufficiently implausible that we'd fault people who make them. But there is indeed a hot debate on the subject, involving some pretty serious people on both sides. There is evidence that some say points towards biological differences, and that others think is not probative enough (since it's so hard to isolate biological causes from social causes). There is the unquestioned reality that men and women are materially different chromosomally, hormonally, and physically, and that male and female animals of other species (where the explanation must presumably be biology and not "culture" divorced from biology) are often different in temperament and behavior. This at least suggests that looking for possible biological cognitive and temperamental differences and differences in distribution of various traits, alongside the chromosomal, hormonal, and physical differences, is not obviously a fool's errand — and thus is plausible fodder for conjecture and discussion of suggestive evidence, even in the absence of conclusive proof.

We have, as best I can tell from my layman's perspective, a serious and potentially intellectually exciting debate here. Shutting off one side, imposing on one side requirements of "proof" that bar the proposal of scientific conjectures, or for that matter imposing on both sides such requirements, strikes me as bad both for our knowledge of this subject and for scientific debate more generally.

UPDATE: In the post in which I first mentioned Prof. Barres' article, I linked to the article and also to an Edge.org debate between Steven Pinker and Elizabeth Spelke.

I probably should have also, for balance, linked to an article that takes the view contrary to Prof. Barres'; since I suspect that the attention on this thread has shifted from that post to this more recent one, I decided to add that link here -- it's to Kingsley Browne, Women in Science: Biological Factors Should Not Be Ignored, 11 Cardozo Women's Law Journal 509 (2005). Browne's piece is just a short version of some much longer work he's done, but I figure that shorter is often better for at least a first look at the matter. I stress again that I'm not claiming I know what the right answer is; I'm just trying to pass along pointers to both sides of the argument.

Credentials and Interdisciplinary Work:

A commenter on an earlier thread faults me for citing Prof. Browne's work as a counterpoint to Prof. Barres':

ev loses significant credibility with me when he attempts to "balance" an article about a scientific subject, written by an expert in the field and published in nature, with an article by a law professor with no scientific expertise in a (presumably student-edited) law review. granted, the nature article was not peer-reviewed either, but the author at least had the credentials and experience to know what he was talking about.

This highlights, I think, an important and oft-forgotten point: While laypeople understandably care about experts' credentials — we lack the talent, time, or both to evaluate the underlying data ourselves — it helps to scrutinize credentials with some care, especially since scholars often cross disciplinary boundaries.

Prof. Browne, for instance, is a law professor who has been trained as a lawyer; but his legal interests have led him to the interdisciplinary field of law and evolutionary biology. Besides law review articles, he has also written two books published by university presses, Divided Labours: An Evolutionary View of Women at Work, in Yale University Press's Darwinism Today series, and Biology at Work: Rethinking Sexual Equality, in Rutgers University Press's Series in Human Evolution. I haven't read the books — I've only looked at Prof. Browne's shorter work — but my sense is that writing such books (1) is not at all outside the competence of an intelligent law professor with a job that permits him to do interdisciplinary work, and (2) will give even someone who doesn't have a Ph.D. in psychology or biology, and who doesn't have an appointment in the psychology or biology department, a pretty broad and deep knowledge of the experimental literature. I'd take quite seriously what Judge Posner has to say about economics, though he's trained as a lawyer rather than an economist; I'm sure many economists disagree with much of what he says, but his opinions are nonetheless worth considering despite his academic background. Likewise with Prof. Browne.

Prof. Barres is indeed trained as a neurobiologist, and is a Professor of Neurobiology. He has written extensively on neuorobiology, and neurobiologists are likely to find work on genetics and cognitive psychology to be quite accessible. On the other hand, Prof. Barres' list of publications does not seem to include any scholarly work on gender differences, unless I've missed some, and setting aside any pieces too recent to include (such as his Nature essay).

It is possible that Prof. Barres has read as deeply and broadly as Prof. Browne on the subject, or even more deeply and broadly. It is possible that he has read less. Whether or not Prof. Barres has studied this field more than Prof. Browne has, Prof. Browne's books on the subject suggest that Prof. Browne has read enough to be taken seriously. In any event, I would not casually dismiss either Prof. Barres' opinion or Prof. Browne's, regardless of the departments in which they teach, the degrees that they have, or the nature of the journal in which they published their shorter work.

Prof. Ben Barres' Response:

Stanford Prof. Ben Barres e-mailed me about my earlier criticisms of his Nature article; I then e-mailed him back, and he responded further, kindly agreeing to let me post our exchange. Here are the relevant parts, starting with Prof. Barres' first e-mail (some paragraph breaks added):

I noticed your blog comments about your discomfort with my comment about verbal violence in my recent Nature commentary. If I may clarify, I wouild definitely not like to squash free discussion of ideas in any way. But I would like to draw a line between a faculty member conducting a free discussion as compared to a faculty member teaching that women are innately less good as fact in a classroom. For one thing it's not a fact, for another by teaching it as fact he makes it so. Studies have shown, for instance, that when teachers are told a group of their students are less intelligent, that they in fact perform less well. Teaching that a group of people is innately less good is extraordinarily damaging, as you would realize if you were personally subject to the harmful consequences of discrimination (no offense intended--but do you not think it is meaningful that pretty much the only people defending Larry Summers are white men?).

There is a faculty member here at Stanford, Bill Hurlbut, who is on the Presidential Ethics Committee that makes recommendations on embryonic stem cell research. He is deeply religious and I personally disagree with his views about banning stem cell research. However, I would defend his right to discuss this subject in the classroom. Whenever he teaches, he discusses a controversial topic fully by encouraging students to bring up and discuss and explore all possible viewpoints. The students never have any idea what his own personal viewpoint is and he discusses deeply all viewpoints in a balanced and fair way. This is very different than Professor Harvey Mansfield teaching in his classroom that women are innately inferior (I really don't care what he says outside of a classroom to his friends and relatives). That he has done this is documented in the Harvard Crimson. When faculty tell women they are less good, this causes them to do less well, demoralizes them, and tells them they are not welcome.

I responded that my original reading was based on Prof. Barres' focus on Summers' out-of-class statements (a matter I discussed in the quasi-footnote here), and Prof. Barres graciously replied that "I can see why you would have come to your original interpretation as there was some (unintended) ambiguity. It was not my intended meaning." But I also went on to probe a little further Prof. Barres' views about the in-class statements:

Also, I think there's much to a pedagogical style in which "The students never have any idea what [a teacher's] own personal viewpoint is and he discusses deeply all viewpoints in a balanced and fair way"; my sense, though, is that most universities generally don't require such a teaching style these days. Say that Steven Pinker, who may well be mistaken, as you argue, but who presumably has some nonridiculous reasons for thinking that his view is correct, teaches a class in which the question of sex differences comes up. He discusses deeply all viewpoints (subject perhaps to inevitable time constraints) in a balanced and fair way, but also mentions that his view is that the data points to biological sex differences being part of the reason for the disproportionate representation of men in the sciences. Would that too be intolerable and verbal violence?

Prof. Barres in turn responded:

Don't get me wrong. I am not saying that someone that does this should be put in jail. I am simply saying that to tell young people that they are innately inferior is deeply harmful. It is presently scientifically impossible to sort out with any degree of certainty the effects of social forces and prejudice, which are more than amply demonstrated to be large, from any possible innate effects. Therefore any faculty member who pronounces in a classroom that a whole group of people is wired to be inferior is causing great harm without having strong evidence to back his contention. If I were president of Harvard University and I had a faculty member that was doing this, I would ask them to feel free to have a full and balanced discussion on the topic, and to feel free to discuss any and all aspects of the question, but that they should stop short of pronouncing that science had demonstrated that a group of people was innately inferior (be it Jews, African-Americans, gay people, or women). It is hard for me to see any strong argument for not taking the course of action that is least harmful. Since tolerance and free speech are both important values, I don't see why one of them should always win out over the other, instead of their being an appropriate balance. (It bothers me deeply that there is an asymmetry here--overwhelminingly it is only white men who argue that its ok for faculty to categorize women or minorities as innately inferior ....).

I agree that people "should stop short of pronouncing that science had demonstrated that a group of people was innately inferior," unless they really have good evidence that science has so demonstrated. Certainly statements about such scientific questions should be no more confident than the data warrants.

Yet I'm also struck by Prof. Barres' reaction to my hypothetical, in which a professor merely discusses the data thoroughly in class and "also mentions that his view is that the data points to biological sex differences being part of the reason for" a phenomenon. To his credit, Prof. Barres does say "I am not saying that someone that does this should be put in jail." But he goes on to say, in a paragraph prompted by the same hypothetical, that "to tell young people that they are innately inferior is deeply harmful," and "[s]ince tolerance and free speech are both important values, I don't see why one of them should always win out over the other, instead of there being an appropriate balance."

In principle I agree that we should take "the course of action that is least harmful." But there is great harm, for the reasons I mentioned earlier in this thread, in stifling discussion of possible innate sex differences, and that stifling seems to me to be precisely what Prof. Barres' analysis calls for.

Before science can be said to "demonstrate" something "with any degree of certainty," scientists have to be able to discuss their tentative findings, both among themselves and with students (who will often end up being fellow scientists). If we're going to have a serious scientific debate, which will likely span decades and generations, we can't demand that one side say nothing (at least to students) about where it thinks the data points, while the other side is free to express its views.

If we're concerned about the possible harm that such conjectures may cause simply from their being heard, I think it's far better to educate students about probabilities, and to show that even if there are biological differences between men and women as populations, they don't tell us much about the qualities of a particular man or a particular woman. We shouldn't have a truncated scientific debate, for fear that some might be dispirited by one side's conjectures. Nor should we have some sort of secret debate that is allowed to go on only among professors because it's seen as too unpleasant or dangerous to be exposed to mere students.

This is especially so because, to his credit, Prof. Barres isn't even saying that the view that innate sex differences exist, and form a part of the explanation for the observed disproportions, is factually wrong. Rather, he says that "[i]t is presently scientifically impossible to sort out with any degree of certainty the effects of social forces and prejudice, which are more than amply demonstrated to be large, from any possible innate effects [by which I presume he means innate causes]."

Now it seems to me that if it impossible to do this sorting, then it's hard to accurately estimate "the effects of social forces and prejudice." Evidence of the presence of such social forces and prejudice can't really tell us much about the magnitude of the real-word effects of those forces, given that the observed effects might stem from other causes (and might do so to a "scientifically impossible to sort out" degree).

But in any event, science has not, I think, generally advanced by saying "it's presently scientifically impossible to sort out with any degree of certainty" X and Y, and thus abandoning the project of sorting them out, or of making conjectures at weaker levels of certainty. Rather, scientists have looked closely at evidence, made their best guesses, and over time improved their scientific tools and crafted theories that are helpful even if they lack the certainty that some might prefer. Likewise, while the impossibility of certainty should caution people against claiming certainty that the facts don't support, it shouldn't stop people from investigating the facts and reporting what they see as the directions in which the facts seem to point.