But men genuinely are interested, or at least act interested, in women. They’re nice to them, they do things for them, they hold back an enormous amount of their behavior, including aggressive and competitive (and gross) behavior, around them. When men do turn against women, there’s a vengeful sort of relentlessness to it. The violence of the betrayal of instinct and the revenge of transgression and unleashed restraint. It’s not how they instinctively want to relate to them, and so it gathers reactive force.

There are basic, physical things about women that trigger deeply programmed responses in the human brain, just as there are with adults and children. And in fact they’re some of the same tricks. The high soft voice, smooth hairless skin, larger more widely set eyes, a softer, less aggressive manner, a more delicate physicality, increased deposits of subcutaneous tissue. Those are all examples of natalism. The tendency of physical festures associated with childhood (and thus programmed responses to childhood) in adults. The response to those big eyes is so fundamental it even works across species. Humans can’t help but gush over a puppy, even though it’s not even one of the young of their own species. They hear those high voices, feel that soft face, see those big eyes, and melt. Domesticated animals, like dogs, retain these endearing physical traits into adulthood. That’s one of their distinctive features. And so do women. What do men get? Aggressive musculature, overdeveloped brows and chins, back hair, and male pattern baldness. So clearly men are going to have to work a bit harder to make themselves instinctively loveable, rather than threatening.

Most men can’t help feeling the reaction “Oh, it’s a woman, how nice, I had better restrain myself”, any more than most humans can ignore their instinctive reactions to puppies, and small children. I have two little girls, and I’ve seen people overcome by altruistic instincts at the mere sight of them. I’ve seen flinty-jawed, irascible old men suddenly soften. I’ve seen blatant prejudice. The mechanisms are buried so deeply in us, beyond conscious thought. You can criticize them all you like, if you think that’s somehow helpful for the species, but you can’t pry it out of us. And if you ever did, you might not like the results.

Now, obviously men and women are often friends, although far less often than men are friends with men and women with women. People and their relationships are complex enough that most people need to be forced together to overcome significant barriers of difference.

Most people gravitate toward what’s easy. We’re friends with whoever is convenient because of our interests, work, and established social life. We’re friends with people who are close to us because they’re in our workplace or school or house, or just related to us. We’re creatures of convenience, and proximity matters a lot, even in important relationships like marriage. Difference in sex alone can provide a large enough barrier to make it too much work to be deeply interested in or involved with someone of a different sex.

Unless, of course, there’s the possibility of coupling on the table. That’s provides a huge motivation, even when it’s only a minor possibility, to connect to people and prove your value in the eyes of the opposite sex.

People are complex, of course, both in what attracts them (as people, in a general sense) to one another, and what pushes them apart. Convenience, shared interests, kinship, similar personalities, similar values, and yes, physical attraction (even outside the possibility mating, we are just generally interested in attractive people).

Having read a good bit about child development and the sexes, children reach this natural point where they start self selecting into different groups based on gender. The boys are generally more comfortable with and interested in the play of boys, and girls are more comfortable with and interested in the play of girls. There’s plenty of overlap, but there’s enough difference that its a ubiquitous phenomenon. And you see it happen in nature, among other mammal species, all the time.

So what drives them back together, not one by one through individual means and connections, but as a whole group, as a herd? What brings these diverging halves of the species back together? What could possibly bring these two groups that are so different they could almost be considered separate subspecies (and have in fact, separate genetic lineages) back to reform into one species instead of just going their own way? What could overcome all the fear, confusion, disinterest, disgust, prejudice, lack of understanding, cultural differences, physical and emotional mismatching, and the cooties?

Sexual maturity. Adolescence, the transformation into sexually mature members of the species lights the fire that brings us back together. Just as it does for so many species. Our need to recombine to continue the species drives us back together. It lights the fire under us. Men, especially, might remain half socialized nitwit after hitting adolescence, if it weren’t for the fact they feel driven back to the female half of the species and feel driven to impress them and cater to their desires, to sculpt themselves and the world for women in some way that will impress them and invite acceptance.

And so I wonder, how much interest would men take in women if they didn’t have such a desperate need and desire for them and their affections? The excessive imbalance in how much men feel driven by that need has been well observed and documented, if not well publicized. Everyone knows it by experience, and any time anyone has set out to study it the results are almost laughably easy to come by, and remain more consistent across time and culture (and even different species) than almost any sociological phenomenon you discover. The driving force of testosterone doesn’t just drive sexual intersest and physical strength, it’s a major source of male energy and ambition and drive and tenacity. Ask a man who has had his testosterone wiped out by prostate cancer treatments how he feels and he’s likely to break down in tears and tell you he feels he’s lost who he is.

So how sustainable would relationships across the sexes be if you took away sexual attraction and prejudicial interest and regard? What would it look like if men stopped being men and stopped seeing women as women? One possible place to look for the answer is to look at the relationships between gay men and lesbians. As much as they have worked together to support mutual causes, there is actual little community or regard between them. They have very little use for one another and tend to self segregate into their own separate enclaves, much like the children did. You rarely see them together, of their own accord. Without the need to reunite the species for intersex propagation, they remain apart and go their separate ways, happy in their own worlds, with no need for the other.

Men who have started having affairs, or couples who have become physically distant are another example. It’s very hard for men to invest emotionally apart from a physical investments. The physical investment does a huge amount of work in securing and developing their physical attachment.

I’ll be perfectly honest about myself, I’ve had a haircut that also included a really good neck massage. And it was hard not to fall a little bit in love with my hairdresser, for no better reason than that she was young, lovely, and showed great physical kindness to me. It’s very hard for a man not to fall just a little in love for such small reasons. Women seem to have a greater power to resist such deductions, even from their own partners they carry less weight. But different kinds of kindness, generosity, and regard can impress them. Both men and women greatly appreciate generosity, albeit they tend to get more from different types of generous behavior. The thought that, as a modern man, it won’t harm your first impressions if you don’t pick up the check or if you display any kind of cheapness on a first date, is a sadly misguided one.

There are a lot of huge prejudices women don’t like to admit they have that shape the relations between the sexes. In fact humans are the only species of the large primates in which male selection exists. Among all the others in our class, the females are very selective, and the males compete among themselves for the right to be the accepted winner of their affections.

Human females can be quite picky. For example, they will only very rarely choose a mate who is younger than them, and almost never someone who is shorter than them. They will almost never choose a mate below their own social and financial status. Women marry across and up, with extreme prejudice. And if a man falls down below their status, they are not very understanding.

Apart from the question of how much women would be interested in or have society with women without sex, there is a second, possibly just as big a question of how much human and social effort men would engage in without women. Looking at frontier situations like the old west and college apartments, the emergence of anything remotely resembling civilization and the niceties of society hardly ever seems to emerge except insofar as men are attempting to prepare the space to be acceptable to women. And in many of the old west town it was, interestingly enough, the prostitutes, the first women in those areas who demanded and founded a large part of the social development of those places (schools, care, sanitation, social services, legal and behavioral standards, cultural institutions, art all those little niceties that make up, you know, civilization).

If there were no demand on the part of women that men make themselves and their environments meet their standards for cohabitation, would men develop these things of their own accord? Would they develop themselves? Possibly. But likely to a far lesser degree and at a far slower rate. How much have we all done just to make our mothers proud? How much to win the attention of girls, how much to win the approval of our spouses.

Looking at the current trend in our society, with rates of marriage falling and less investment in the opposite sex in general expected, especially long-term investment, what have some of the outcomes been? Are men still bothering to improve themselves and their environment as much? Or are the becoming more and more pathetic with no standard to be held to? With pornography easily available for substitutionary pleasure, what is their motivation for subjecting either themselves or the world to the difficult process of taming and maturity and conversion to productivity?

I lose tolerance for differences when not having sex. Sex is a reminder, an illustration that somehow, despite our difference we fit together.

I think the crux of the problem is, considering that men are more aggressive, less sociable, less agreeable, less concerned with others in general for many essential structurao reasons, if you take away sex as a motivator for pushing them back into connection with humanity, particularly with that part of humanity they really need to balance and tame their more aggressive virtues and make them productive, what is the likely result? I’m not as sociable or even socially needy as my wife. So if I genuinely lost interest in sex, if that motivator toward her was gone, there would be a lot less energy in me to drive my investment in the relationship. I don’t feel like I need other people or need to care about other people that much. But sex makes me care. I don’t think women care more purely for some abstract altruistic reason either, there are biological and instinctive motivators there too, just different expressions.

I think the main result of a loss of interest in sex would simply be a growing indifference about women and the concerns of women and the challenge of interacting with women in general. Unfortunately, indifference is one of those traits that make serious relationships like marriage extremely hard to maintain. And let’s be honest, society in a broader level, the species, is a marriage between the sexes. And as hard as sex can be, without it it isn’t clear that the marriage between the sexes could survive the resulting indifference.

It shouldn’t be a surprise, this. It’s not like humans are ignorant of the natural world. If you asked any biologist, what would happen to a species if they stopped being interested in sex, the answer would be, that would be the end of the species in every sense. Many of its behaviors and social structures, except possibly feeding, would cease, and in short order so would the whole species.

In fact that’s one of the reasons pandas are so darn hard to keep from going extinct. They don’t seem to be very motivated to keep pandas going themselves. Mating programs are notoriously difficult, and the amount of effort required to get a species to procreate who doesn’t seem to care about it much is very high.

Without the abstract motivation of sex, birds wouldn’t sing or have bright colors or perform extravagant displays. The magnificent size and horns of bulls wouldn’t exist, and neither would the udders and rich milk of cows. The colorful backsides of baboons would cease to glow, and the structure of their troops would disintegrate. Deer wouldn’t bother growing horns and elk would cease bugling. Salmon wouldn’t bother making their annual run. Mayflies wouldn’t waste their lives for the few short hours of flight it takes to mate. Plants wouldn’t waste energy on producing flowers. Bower birds wouldn’t make their nests and lyre birds wouldn’t bother making their complex songs. Flamingos wouldn’t dance. Bighorn sheep wouldn’t bother with the big horns. Elephant seals wouldn’t bother mastering any beaches or need to be elephantine. Bees wouldn’t need queens. Whales wouldn’t bother with heat runs. Rays wouldn’t leap from the waves. Innumerable birds and fish and mammals wouldn’t waste time on their migrations to their mating grounds. Stallions and rams wouldn’t bother protecting their herds.

In other words, apart from the end of all complex life and society (even animal societies, which isn’t nothing), all the color would go out of the world. So much of what is wild and amazing and wonderful would cease to be. So much of the character of life would be lost. So before we’re ready to dispose of something that has given us so much, given us everything, because it has also given us some bad things, we might want to hesitate. Maybe eliminating a systemically corrupt evil would actually deprive us of one of our most essential mechanisms for good. Maybe our concern should be excellence and good management rather than rejection and disillusionment. I think we need to be careful what we wish for.