Motus Mentis

Last night we had friends over for dinner, a lovely couple we know from Wellfleet. They are both academics: she is a sociologist and associate professor at Harvard.

Naturally we were discussing the recently transformed political landscape, and the conversation turned to Mr. Obama’s possible choices for the composition of his cabinet. Among the names that came up was that of Lawrence Summers, the former Treasury Secretary who may serve in that role again in the new administration. He was also the president of Harvard University from 2001 until 2006, when he resigned after some remarks he made sparked a feverish social and political brouhaha.

At the mention of his name, our guests immediately expressed harsh disapproval. I replied that I had never understood what was so troubling about Dr. Summers’ comments, and a lively debate ensued.

Dr. Summers, on his day of infamy, addressed the question of why women are underrepresented at the upper levels of science, engineering, and mathematics. He was keenly aware that this is a political minefield, but was trying, as gingerly and deferentially as he could, to explore the reasons this might be so. (You can read the fateful speech here).

In his address, he makes clear from the outset that the women-in-science issue is only one example of underrepresentation:

…I am going to, until most of the way through, attempt to adopt an entirely positive, rather than normative approach, and just try to think about and offer some hypotheses as to why we observe what we observe without seeing this through the kind of judgmental tendency that inevitably is connected with all our common goals of equality. It is after all not the case that the role of women in science is the only example of a group that is significantly underrepresented in an important activity and whose underrepresentation contributes to a shortage of role models for others who are considering being in that group. To take a set of diverse examples, the data will, I am confident, reveal that Catholics are substantially underrepresented in investment banking, which is an enormously high-paying profession in our society; that white men are very substantially underrepresented in the National Basketball Association; and that Jews are very substantially underrepresented in farming and in agriculture. These are all phenomena in which one observes underrepresentation, and I think it’s important to try to think systematically and clinically about the reasons for underrepresentation.

In studying the issue of the number of women in science there are, broadly speaking, two factors to weigh: purely social causes such as cultural influence and discrimination at the universities, and the possibility that there is something innately different, on average, between males and females that makes it more likely for men to seek out this sort of work, and to excel at it.

Note that the question is a purely empirical one. We have an observed phenomenon before us — that there are more men in the highest echelons of these professions — that we seek to explain. If we actually want to understand what’s going on, the correct procedure is to gather what data we can, form various hypotheses, and put them to the test.

Dr. Summers suggested three possible causes that he thought likely, which depended to differing extents upon the two broad categories of innate and social factors. The first was that women might tend to be less inclined to want jobs that demand taking top priority in one’s life. In his words:

There are three broad hypotheses about the sources of the very substantial disparities that this conference’s papers document and have been documented before with respect to the presence of women in high-end scientific professions. One is what I would call the-I’ll explain each of these in a few moments and comment on how important I think they are-the first is what I call the high-powered job hypothesis. The second is what I would call different availability of aptitude at the high end, and the third is what I would call different socialization and patterns of discrimination in a search. And in my own view, their importance probably ranks in exactly the order that I just described.

Maybe it would be helpful to just, for a moment, broaden the problem, or the issue, beyond science and engineering. I’ve had the opportunity to discuss questions like this with chief executive officers at major corporations, the managing partners of large law firms, the directors of prominent teaching hospitals, and with the leaders of other prominent professional service organizations, as well as with colleagues in higher education. In all of those groups, the story is fundamentally the same. Twenty or twenty-five years ago, we started to see very substantial increases in the number of women who were in graduate school in this field. Now the people who went to graduate school when that started are forty, forty-five, fifty years old. If you look at the top cohort in our activity, it is not only nothing like fifty-fifty, it is nothing like what we thought it was when we started having a third of the women, a third of the law school class being female, twenty or twenty-five years ago. And the relatively few women who are in the highest ranking places are disproportionately either unmarried or without children, with the emphasis differing depending on just who you talk to. And that is a reality that is present and that one has exactly the same conversation in almost any high-powered profession. What does one make of that? I think it is hard-and again, I am speaking completely descriptively and non-normatively-to say that there are many professions and many activities, and the most prestigious activities in our society expect of people who are going to rise to leadership positions in their forties near total commitments to their work. They expect a large number of hours in the office, they expect a flexibility of schedules to respond to contingency, they expect a continuity of effort through the life cycle, and they expect-and this is harder to measure-but they expect that the mind is always working on the problems that are in the job, even when the job is not taking place. And it is a fact about our society that that is a level of commitment that a much higher fraction of married men have been historically prepared to make than of married women. That’s not a judgment about how it should be, not a judgment about what they should expect. But it seems to me that it is very hard to look at the data and escape the conclusion that that expectation is meeting with the choices that people make and is contributing substantially to the outcomes that we observe.

…Another way to put the point is to say, what fraction of young women in their mid-twenties make a decision that they don’t want to have a job that they think about eighty hours a week. What fraction of young men make a decision that they’re unwilling to have a job that they think about eighty hours a week, and to observe what the difference is. And that has got to be a large part of what is observed. Now that begs entirely the normative questions-which I’ll get to a little later-of, is our society right to expect that level of effort from people who hold the most prominent jobs? Is our society right to have familial arrangements in which women are asked to make that choice and asked more to make that choice than men? Is our society right to ask of anybody to have a prominent job at this level of intensity, and I think those are all questions that I want to come back to. But it seems to me that it is impossible to look at this pattern and look at its pervasiveness and not conclude that something of the sort that I am describing has to be of significant importance.

Summers is bending over backward here to acknowledge that the disparity between the numbers of women who are willing to sacrifice everything to reach the pinnacle of demanding professions may well be due to normative social factors. His point is simply that as matters stand, it seems that more men than women are indeed willing to do so.

The next suggestion Dr. Summers makes is the one that cost him his job. He points out that empirical data appear to show that on a variety of quantifiable attributes, men tend to show greater variation: that is to say that when the distribution of the attribute in question is examined, men show larger standard deviations than women. In terms of, say, mathematical aptitude, this means that compared to women, there are more men at both extremes: not only more men who have exceptional talent, but also more men who are exceptionally lacking. However, because high achievement in the sciences requires exceptional aptitude, there will naturally be a larger pool of highly qualified men than women.

Here is the full transcript of this section of Dr. Summers’ remarks:

It does appear that on many, many different human attributes-height, weight, propensity for criminality, overall IQ, mathematical ability, scientific ability-there is relatively clear evidence that whatever the difference in means-which can be debated-there is a difference in the standard deviation, and variability of a male and a female population. And that is true with respect to attributes that are and are not plausibly, culturally determined. If one supposes, as I think is reasonable, that if one is talking about physicists at a top twenty-five research university, one is not talking about people who are two standard deviations above the mean. And perhaps it’s not even talking about somebody who is three standard deviations above the mean. But it’s talking about people who are three and a half, four standard deviations above the mean in the one in 5,000, one in 10,000 class. Even small differences in the standard deviation will translate into very large differences in the available pool substantially out. I did a very crude calculation, which I’m sure was wrong and certainly was unsubtle, twenty different ways. I looked at the Xie and Shauman paper-looked at the book, rather-looked at the evidence on the sex ratios in the top 5% of twelfth graders. If you look at those-they’re all over the map, depends on which test, whether it’s math, or science, and so forth-but 50% women, one woman for every two men, would be a high-end estimate from their estimates. From that, you can back out a difference in the implied standard deviations that works out to be about 20%. And from that, you can work out the difference out several standard deviations. If you do that calculation-and I have no reason to think that it couldn’t be refined in a hundred ways-you get five to one, at the high end. Now, it’s pointed out by one of the papers at this conference that these tests are not a very good measure and are not highly predictive with respect to people’s ability to do that. And that’s absolutely right. But I don’t think that resolves the issue at all. Because if my reading of the data is right-it’s something people can argue about-that there are some systematic differences in variability in different populations, then whatever the set of attributes are that are precisely defined to correlate with being an aeronautical engineer at MIT or being a chemist at Berkeley, those are probably different in their standard deviations as well. So my sense is that the unfortunate truth-I would far prefer to believe something else, because it would be easier to address what is surely a serious social problem if something else were true-is that the combination of the high-powered job hypothesis and the differing variances probably explains a fair amount of this problem.

There may also be elements, by the way, of differing, there is some, particularly in some attributes, that bear on engineering, there is reasonably strong evidence of taste differences between little girls and little boys that are not easy to attribute to socialization. I just returned from Israel, where we had the opportunity to visit a kibbutz, and to spend some time talking about the history of the kibbutz movement, and it is really very striking to hear how the movement started with an absolute commitment, of a kind one doesn’t encounter in other places, that everybody was going to do the same jobs. Sometimes the women were going to fix the tractors, and the men were going to work in the nurseries, sometimes the men were going to fix the tractors and the women were going to work in the nurseries, and just under the pressure of what everyone wanted, in a hundred different kibbutzes, each one of which evolved, it all moved in the same direction. So, I think, while I would prefer to believe otherwise, I guess my experience with my two and a half year old twin daughters who were not given dolls and who were given trucks, and found themselves saying to each other, look, daddy truck is carrying the baby truck, tells me something. And I think it’s just something that you probably have to recognize. There are two other hypotheses that are all over. One is socialization. Somehow little girls are all socialized towards nursing and little boys are socialized towards building bridges. No doubt there is some truth in that. I would be hesitant about assigning too much weight to that hypothesis for two reasons. First, most of what we’ve learned from empirical psychology in the last fifteen years has been that people naturally attribute things to socialization that are in fact not attributable to socialization. We’ve been astounded by the results of separated twins studies. The confident assertions that autism was a reflection of parental characteristics that were absolutely supported and that people knew from years of observational evidence have now been proven to be wrong. And so, the human mind has a tendency to grab to the socialization hypothesis when you can see it, and it often turns out not to be true. The second empirical problem is that girls are persisting longer and longer. When there were no girls majoring in chemistry, when there were no girls majoring in biology, it was much easier to blame parental socialization. Then, as we are increasingly finding today, the problem is what’s happening when people are twenty, or when people are twenty-five, in terms of their patterns, with which they drop out. Again, to the extent it can be addressed, it’s a terrific thing to address.

Dr. Summers here is acknowledging the intense discomfort that any whiff of innate differences causes in a community where it is a near-religious creed that all human inequities are man-made, and remediable by enlightened policymaking. He allows that he “would far prefer to believe something else, because it would be easier to address what is surely a serious social problem if something else were true”. But he appreciates that wishing doesn’t make things so, and, consistent with the spirit of rigorous inquiry that Harvard, one would think, ought to be emblematic of, he accepts the possibility that there may indeed be other factors than social ones at work here. As Churchill said: “You have to look at the facts, because they look at you.”

Finally, Dr. Summers takes up the question of discrimination, which he agrees does indeed exist:

The most controversial in a way, question, and the most difficult question to judge, is what is the role of discrimination? To what extent is there overt discrimination? Surely there is some. Much more tellingly, to what extent are there pervasive patterns of passive discrimination and stereotyping in which people like to choose people like themselves, and the people in the previous group are disproportionately white male, and so they choose people who are like themselves, who are disproportionately white male. No one who’s been in a university department or who has been involved in personnel processes can deny that this kind of taste does go on, and it is something that happens, and it is something that absolutely, vigorously needs to be combated.

But if all the university faculties are refusing to hire highly qualified and motivated women, this must mean that there is a pool of such women out there, available to any institution that is willing to take them on:

If it was really the case that everybody was discriminating, there would be very substantial opportunities for a limited number of people who were not prepared to discriminate to assemble remarkable departments of high quality people at relatively limited cost simply by the act of their not discriminating, because of what it would mean for the pool that was available. And there are certainly examples of institutions that have focused on increasing their diversity to their substantial benefit, but if there was really a pervasive pattern of discrimination that was leaving an extraordinary number of high-quality potential candidates behind, one suspects that in the highly competitive academic marketplace, there would be more examples of institutions that succeeded substantially by working to fill the gap. And I think one sees relatively little evidence of that.

This inclines him, although he knows it is going to rub a lot of people the wrong way, toward the conclusion that there are probably intrinsic factors — at least to some extent — in play here.

So my best guess, to provoke you, of what’s behind all of this is that the largest phenomenon, by far, is the general clash between people’s legitimate family desires and employers’ current desire for high power and high intensity, that in the special case of science and engineering, there are issues of intrinsic aptitude, and particularly of the variability of aptitude, and that those considerations are reinforced by what are in fact lesser factors involving socialization and continuing discrimination. I would like nothing better than to be proved wrong, because I would like nothing better than for these problems to be addressable simply by everybody understanding what they are, and working very hard to address them.

Dr. Summers then goes on to outline, in a long paragraph that I will not copy here, a number of directions for further research that he thinks might be promising: looking at (using such metrics as numbers of citations of papers written by hirees) what the long-term academic outcome of aggressive diversity-hiring programs has been, comparing the results of objective-standards hiring practices to those that favor diversity, examining the effect of financial incentives and leave-of-absence programs on the quality and composition of faculties, and so on.

Finally, Dr. Summers makes it clear that he understands that this is an awkward topic, and suggests again that he hopes to be proven wrong.

Let me just conclude by saying that I’ve given you my best guesses after a fair amount of reading the literature and a lot of talking to people. They may be all wrong. I will have served my purpose if I have provoked thought on this question and provoked the marshalling of evidence to contradict what I have said. But I think we all need to be thinking very hard about how to do better on these issues and that they are too important to sentimentalize rather than to think about in as rigorous and careful ways as we can.

This, then, is the heresy for which Lawrence Summers was defamed, defrocked, and all but defenstrated: the unspeakable idea that there may indeed be innate, statistically measurable differences between men and women. This is not to say, of course — and it is impossible to overemphasize this point — that any of what Dr. Summers is suggesting here applies in any way to any individual person. He is simply adducing available statistical data to suggest an eminently reasonable — and falsifiable — hypothesis about why there might be more men than women in the uppermost tiers of science and engineering. He wrongly assumed that one of the world’s pre-eminent institutions of higher learning might be intellectualy open-minded enough to give the matter a fair and dispassionate looking-into; instead, the villagers encircled his office with torches and pitchforks, and he was run out of town on a rail. I imagine that this affair still haunts him — indeed, the sharply negative reaction of our guests last night to the mere mention of his name confirms my suspicion — and that he will as a result have no role in the Obama administration.

One of Dr. Summers’ few defenders at Harvard was faculty member and evolutionary psychologist Steven Pinker (author of the excellent book The Blank Slate, which you all ought to read). When he was interviewed by the Harvard Crimson about the controversy, he had this to say:

CRIMSON: From what psychologists know, is there ample evidence to support the hypothesis that a difference in “innate ability’ accounts for the under-representation of women on science faculties?

PINKER: First, let’s be clear what the hypothesis is””every one of Summers’ critics has misunderstood it. The hypothesis is, first, that the statistical distributions of men’s and women’s quantitative and spatial abilities are not identical””that the average for men may be a bit higher than the average for women, and that the variance for men might be a bit higher than the variance for women (both implying that there would be a slightly higher proportion of men at the high end of the scale). It does not mean that all men are better at quantitative abilities than all women! That’s why it would be immoral and illogical to discriminate against individual women even if it were shown that some of the statistical differences were innate.

Second, the hypothesis is that differences in abilities might be one out of several factors that explain differences in the statistical representation of men and women in various professions. It does not mean that it is the only factor. Still, if it is one factor, we cannot reflexively assume that different statistical representation of men and women in science and engineering is itself proof of discrimination. Incidentally, another sign that we are dealing with a taboo is that when it comes to this issue, ordinarily intelligent scientists suddenly lose their ability to think quantitatively and warp statistical hypotheses into crude dichotomies.

As far as the evidence is concerned, I’m not sure what “ample’ means, but there is certainly enough evidence for the hypothesis to be taken seriously.

For example, quantitative and spatial skills vary within a gender according to levels of sex hormones. And in samples of gifted students who are given every conceivable encouragement to excel in science and math, far more men than women expressed an interest in pursuing science and math.

[…]

CRIMSON: [D]id you personally find President Summers’ remarks (or what you’ve heard/read of them) to be offensive?

PINKER: Look, the truth cannot be offensive. Perhaps the hypothesis is wrong, but how would we ever find out whether it is wrong if it is “offensive’ even to consider it? People who storm out of a meeting at the mention of a hypothesis, or declare it taboo or offensive without providing arguments or evidence, don’t get the concept of a university or free inquiry.

Asked whether Dr. Summers’ remarks were “within the pale of legitimate academic discourse”, Dr. Pinker responded:

Good grief, shouldn’t everything be within the pale of legitimate academic discourse, as long as it is presented with some degree of rigor? That’s the difference between a university and a madrassa.

Yes it is. An innate difference, you might even say.