Humans are a mildly sexually dimorphic species.  Which is the fancy way to state the truism that men and women are physically different.  This, I would hope, is obvious, but the obvious often requires restating in order to keep it firmly in mind.  At the same time, it’s worth mentioning that we’re not all that different.  It’s not like we’re different species.  Men aren’t literally Martians and women Venusians, after all.

The important differences all appear to stem from the brute fact that sperm are cheap and eggs are expensive.  To elaborate on that fact, a woman necessarily incurs most of the biologically necessary cost of childbearing.  Minimally, the man makes a donation of genetic material.  Meanwhile, the woman must spend nine months gestating the child.  This period concludes with the life-threatening trauma of childbirth.  And then it’s followed by a couple of years of intensive child raising (including the cost of nursing).  It’s so traumatic that her fertile period ends about halfway through her maximum lifespan.  She could not be expected to bear the cost any later than that.  And she has to do it at least twice in her lifetime in order for the group to break even!

Laying it out like that, it hardly seems fair.  Why should this awful burden be borne almost entirely by the half the population whose random coin flip at birth came up ‘X’ instead of ‘Y’?  Any moral sense or intuition that claims ‘you’ are not entirely ‘your body’ (like, say, Descartesmost religious systems, or Rawls with his veil of ignorance) would imply that this state of affairs is unfair, if not unjust.  And I think that it’s precisely this sense of unfairness that underlies the feminist impulse.

But, evolution being what it is, this simple fact has all sorts of implications that have been written into the very fabric of who we are.  We, as humans, are the heirs of thousands upon thousands of generations of men and women living, struggling, and reproducing under these constraints.  In particular, we are the heirs of the winners.  Our mothers and fathers are proportionately the ones who were, compared to the others of their time, better at doing the whole “making more, better humans” thing, where “better” is defined as “managing to navigate the challenges of life well enough to successfully have offspring, who are in turn better at managing to navigate the challenges of life to make more of their own offspring, and so on, ad infinitum”.

So if we look around at men and women, we see some interesting trends.  Keep in mind that for all of these traits, I’m talking about distributions.  Being people, almost all of these distributions are shaped like the standard bell curve (a so-called “normal” or “Gaussian” distribution).  Bell curves are notable for lots of reasons.  But for now, it’s worth keeping in mind that they describe distributions that are clumped around the “average”.  In fact, all three measures of central tendency (the mean (average in the “add ’em all up and divide by the count” way), the median (“line ’em all up in order and pick the middle one”) and mode (“count each time you see the same number, return the number with the highest count”)) come back the same in the normal distribution.

Deviations from the mean are measured by what’s called the “standard deviation”, which for our purposes can be thought of as a measure of “how far away from the mean do I have to go, in each direction, to encompass most of the numbers”.  One standard deviation in each direction is enough to pick up about 68% of the distribution.  The following diagram should hopefully make this clear:


I say all of this to explain precisely what I mean when I talk in generalities.  If I say something about how “most X do Y” and you think “well, I’m an X, and don’t” – then, congratulations!  You’re not typical.  You might be +/- 3 sigma (the shortcut way of referring to “standard deviation”) on that trait, maybe.  Or more extreme.  Cool!  But that doesn’t change the fact that most people are typical in most ways.  And when you’re trying to look at the big picture, you have to be able to properly weigh the norm with the outliers.  Hence, bell curves.

So, where was I?  Oh, yes, men and women.  It turns out men and women are rather different, physically.  Wikipedia, as usual, has a good summary of the facts here: To begin, men are taller than women.  This should hopefully be glaringly obvious to anyone that has eyes.  But we can do a little bit of the math to get a sense of how this works.  In modern America, the average adult man stands about 5’10” and the standard deviation is 3″.  For women, the average height is 5’4″ and the standard deviation is also about 3″.  On this trait, men and women are equally variable, but men are just taller on average.  Their bell curve is shifted to the right, relative to a female baseline.  But it’s shifted a lot: the difference in the means is 6″, or 2 whole sigma.  That means that there are women out there who are as tall as the average man, but not many of them.  Only about 2.5% of women reach this height.  Conversely, only about 2.5% of men are shorter than the average woman.  If you look at the extremes, it also means that the tallest person in the country is almost certainly a man and the shortest person is almost certainly a woman.

Now, keep in mind there is plenty of overlap in these distributions.  If you randomly pick out one man and one woman from the whole country, it’s perfectly possible that the woman in your pair will be the taller one.  But it’s not terribly likely.  So, in this sense, it’s fair to say that men, as a group, are taller than women.

It turns out that men are also stronger than women.  By a lot.  Now, this was not something that modern life had made obvious.  And modern media, with its depictions of girls who can carry giant guns and beat up guys with the best of them, had given me a pretty skewed view of the situation.  According to the Wikipedia article (and the links it references, like this one:, the distributions of physical strength on almost every measure barely even overlap.  Even trained female athletes whose sport require strong hand grip (who you’d expect to be at the very top of the female distribution) come in, on average, in the 25th percentile on the untrained male distribution.  And this extends beyond hand strength.  Men have, on average, double the lean fiber basically everywhere.

Now, this makes sense if you think about it.  After all, we have separate men’s and women’s sports leagues and Olympic events for a reason.  If we didn’t, there would be virtually no women anywhere who could compete at the highest levels.  The inherent logic of Title IX in collegiate athletics is basically that of Plessy v. Ferguson, the Supreme Court decision that allowed racially segregated schools in the first half of the 20th Century.  Men’s and women’s programs are “separate but equal”.  But because the distributions are so disjoint, this makes sense.  It works.  There’s no one out there calling for integration of sports programs on the grounds of justice between the sexes, like they did in racially integrating the schools.  Instead, people who are concerned with fairness in this arena spend their time arguing that girls’ sports should get just as much funding as the boys’ sports, not that they should play against each other in the same leagues.

I think this fact also explains why feminists tend to be so concerned about the question of violence – especially sexual violence.[1]  If women really are the physically weaker sex, it makes a certain sort of sense for every woman to consider every man a potential rapist.  There’s a pretty good analogy to geopolitics here.  In the anarchic global order, a country needs to be concerned with the capabilities of foreign countries more than their intentions, since intentions can change on a dime.  The same logic holds here.  If there’s very little an individual woman can do to protect herself against any given man if he did decide to attack her, then it doesn’t necessarily matter that none of them would ever do such a thing.  Intentions could change at any moment; plans should center on capabilities.

Moving on, men and women also differ substantially in brain structure and intelligence.  But, unlike height (where the means were different) or strength (where men are basically universally stronger), in intelligence, men and women appear to have about the same mean.  But men have a significantly higher standard deviation than women.  This means that if you give IQ tests to a whole bunch of men and women, many more of the women will be clustered around average, while there will be more male morons and geniuses.

As I mentioned when I began, I think that all of these differences between the sexes are best seen as reflections of (or adaptations to) the core fact that men are inherently disposable and women are inherently valuable.  If your tribe has to have a fight with another tribe, or if you need a group to go out and risk getting gored by dangerous woolly mammoths, you want the fighters to be men.  If they die, no big deal.  The real bottleneck on the next generation is the number of fertile women you have around.  In the worst case scenario, if you have one guy and ten girls, in a year you can have ten kids.  But if you have ten guys and one girl, you can only get one kid.  Hence, it makes total sense for men to specialize in calorie-intensive height and strength.

But, thinking about it a little more, it’s clear that it makes sense for men to specialize in risk of all sorts.  If a valuable woman is lost due to a defect in birth, training, accident, or whatever, that’s a tragedy.  From the perspective of propagating the species and the individual lineage, an average or even mildly below-average woman is great.  If everything just goes as expected, she’s worth her 2-4 kids, plus whatever she herself manages to contribute.  Taking risks for an awesome contribution (either genetically or socially) has a lot of downside.  But an average man isn’t worth much at all.  The best men (by whatever measure) can father all the children needed for the next generation.

So there’s a fundamental asymmetry here.  We are descended from a skewed distribution.   It turns out, in fact, that only about 40% of men managed to reproduce before the modern era, compared to 80% of women.[2]  In other words, our fathers needed to excel in some way to earn a mate; our mothers needed only avoid disaster.  This is why I think the classic fairy tale pattern of the prince slaying the dragon to save the princess resonates on a primal level in a way that the gender-swapped version does not.  The princess is already valuable; it is the prince who needs to prove he is worthy of her, where so many others have failed.

OK, so here comes the really interesting bit.  It turns out that sexual attraction in men and women is accordingly asymmetric.  Men are primarily attracted to a woman’s youth and physical beauty.  Markers of these (like facial symmetry, a healthy weight, lack of wrinkles or blemishes) drive a woman’s value in the sexual marketplace.  Hence, the billions upon billions of dollars spent in the cosmetics industry[3] and on plastic surgery, all by women hoping to push back the clock and retain (or regain) the status of desirable youth they enjoyed as they entered adulthood.  Other features are of course interesting to men (like intelligence, temperament, etc.) but they are secondary.  Most men will reject a potential partner who does not meet his bar for physical attractiveness before he even considers these secondary traits.

Women, on the other hand, appear to be primarily attracted to a man’s social status.  This is why so many ladies claim to find confidence sexy, why girls tend to go for jerks instead of nice guys, and why you find beautiful women flocking all over attractive athletes and trollish politicians[4] alike.  After all, what is a “jerk” but a person who treats other people with disrespect?  In the built-in human hardware, when we see a person treat others with disrespect and not suffer for it, we interpret that as that person successfully claiming superior social status.  Women are wired to find this sort of success innately attractive.

In the secondary traits women find attractive (like intelligence, physical build, etc.), women tend to want to look up to their man.  Again, this makes total sense.  Since more men overall would not reproduce, the distribution of reproducing men is more right-skewed compared to the distribution of women that reproduce. So it would be expected that each woman would tend to match up with a man that exceeded her in most ways (other than beauty).  Our mothers were disproportionately those women who successfully pursued and were pursued by the winners of intra-male status competitions.

To see how this might work, let’s look up at that bell curve and assume that we’re tracking relative overall “attractiveness” within a generation.  Since most everything is normally distributed, it’s fair for a first cut to say that this probably is, too.  If only the top 40% of men make it, that means that the cutoff is about +0.25 sigma or greater.  If the top 80% of women make it, the cutoff is -.8 sigma.  Then, if you pair off each man to two women (a simplification, since the bottom guy probably only barely gets one while the top guy might get a lot more than two, but go with it), starting with the right-most triads and heading left, you’ll see that pretty much every woman has to be paired with a man with a higher score.  If the male standard deviation is bigger (meaning that there are more men on the very far right tail and fewer in the middle) then it works at the top, too: the top man will almost assuredly have a higher score than the top woman.

This difference in sexual attraction explains why so many feminists seem to be drawn to the idea of beauty as a socially constructed phenomenon.[5]  They spend a lot of time railing against the fashion industry or Hollywood as pushing an unrealistic standard of female beauty and claim that it is of utmost importance that this be stopped.  Men tend to think this is crazy.  After all, for men, their sexual response system is pretty much plugged straight into the optic nerve.  For women, though, they experience attraction as mediated through their social subsystem.  They think men are attractive in large part because of what they imagine third parties think.  So it makes total sense to the typical woman that men would be similar, that their attractions would also be strongly influenced by media depictions of who’s hot and who’s not.

Here’s the kicker: if that last bit is true, about women being attracted to men primarily on the basis of social status (and especially higher social status than themselves), then it’s the fatal flaw in the design of the feminist project.  Whatever faults or features it may otherwise have, feminism means nothing if it does not mean that we should raise the status of women in aggregate.  And social status is relative.  You can’t raise someone’s status without lowering someone else’s, so raising women’s status must necessarily lower men’s status in aggregate.

In modern America, the expectation is that every man is supposed to pair off with one woman at a time, a pattern referred to as serial monogamy.  Assume, for the time being, that before feminism became a big deal in the ’60s and ’70s, that the steady state was such that the average man was attractive “enough” to the average woman (and so on up and down the spectrum) to allow for a near-universal rate of reasonably successful pairings.  This seems to have been true.  Most everybody ended up married to somebody and enough kids were had up and down the social scale to keep the population growing at a good clip.

The standard idea of eventual one-time lifelong marriage was complicated here by the fact that men tend to increase in status as they age to a peak in their forties, while women’s attractiveness peaks in their late teens or early twenties.  So if a pairing is equally and happily matched when they are wed, you’d expect over time for the man’s attractiveness to outpace the woman’s, leading to phenomena like the “mid-life crisis” and male infidelity, sometimes resulting in the man initiating divorce to “trade in for a younger model”.  This sort of thing was considered quite unfair to the women involved, and much of the social control budget back then was spent trying to keep men from “altering the deal”.  This contrasts notably with today, where women are initiating the majority of the divorces.[6]

OK, so let’s model the effect of second-wave feminism as raising each woman’s social status by a fixed amount and lowering a man’s status (though not necessarily her mate’s) accordingly.  Once you do this, then everything mismatches again.  The average man is no longer attractive to the average woman.  Notably, though, the effect does not go in reverse (at least not at the first order).  Men’s opinion of women remains largely unchanged, since the stock of physical female beauty hasn’t increased or shrunk.  But we’re still suddenly thrown back to the pre-modern equilibrium.  Only a fraction of the men measure up for most women, so you have hordes of women throwing themselves at the few still desirable men.  Meanwhile, the majority of men who would have seemed like good marriage material before the change remain on the shelf, ignored by women of their cohort until they age into their peak status.

I argue that evidence for this pattern can be seen all over the place: in the stories about the hookup culture on college campuses (where sex is essentially free for desirable men while simultaneously non-existent for most)[7]; the spike in the divorce rate in the ’70s and ’80s, followed by a lower marriage rate[8]; the increasingly late age of marriage (as women have to age out of their prime years to be willing to marry low-status men)[9]; the collapse of the birth rate among high-status, highly educated women[10]; and the stories about women needing to choose between “settling” for a man or never marrying (and perhaps living with a disproportionately large number of cats or dogs).[11]

Most intriguingly, though, I think this explains why self-reported happiness for women has fallen over the time period of the feminist social experiment, while men’s happiness has remained much the same.[12]  Along these lines, women who report “benevolent sexist attitudes” (or, who cleave to the pre-feminist ideal) also score happier[13], which I’d also predict from this.  Basically, when they do mate, women are ending up with much the same men as before because the rank order of attractiveness and male preferences haven’t changed.  But since every male has become globally less attractive, they are now more dissatisfied with the men they eventually end up with.

I find all of this fascinating; there are so many implications!  Most apparent, though, is that it means that if this is right, feminism implies a much bigger shift in a Western-style society than it appears on the surface.  “Men and women ought to be equal”, if you put it into practice, implies massive, deep structural change to core civilization functions.  Among other things, paradoxically, it means women will find their potential mates and the monogamous ideal much less appealing, on average, leading to increased overall female unhappiness.  Moderate feminism, judged as a social technology, cannot succeed on its own terms.