“Virtually no one, it seems, is happy with the state of maleness,” observes Mark Regnerus in the opening pages of his new book, Cheap Sex. It’s not the central point of the book, but this comment serves as a poignant starting point for reflection, especially since a similar claim could be made of “femaleness,” and of relations between the sexes just in general. Is anyone pleased with the state of modern romance? Complaints come in a thousand flavors, but the discontent seems widespread.

Cheap Sex is an important book. As a sociologist, Regnerus has spent years studying American sexual habits, through extensive surveys and batteries of interviews. It’s rare to find such a nuanced discussion of this subject, offered from the perspective of a researcher who is willing to engage progressive assumptions critically. Regnerus does a remarkable job of combining big-picture analysis with copious detail on every modern sexual practice from dating apps to pornography to the rise in female masturbation. It’s hard to imagine any reader getting to the back cover without wanting to quibble. (This reviewer certainly didn’t.) In truth, this is a strength of the book. To the extent that you agree with Regnerus, Cheap Sex offers a treasure trove of supportive data. Insofar as you disagree, it’s an excellent foil.

What do we see when we look at the sexual landscape of contemporary America? In a way, the title says it all. We live in a world where sex is cheap. The choice of an economic term is very deliberate here, because the whole book represents an effort to analyze American sexual practices through the quasi-economic lens of “sexual exchange.” When he claims that sex is cheap, Regnerus isn’t pricing prostitutes. He’s assessing what a person (specifically, a man) must do to secure access to sex. Nowadays the answer is: not much. It has not always been so.

If it seems odd to analyze sex in market terms, consider that people always have reasons for seeking romance. We all hope to gain something in entering into a sexual relationship, whether a marriage, a one-night stand, or anything in between. Men and women tend to want different things, though. Men have a higher sex drive, and are slower to invest emotionally in their relationships. Women enjoy sex too, but intimacy and moral support tend to be higher relationship priorities for them. (Even sex is more pleasurable for women in the context of committed relationships.) The “terms” of our sexual exchanges are continually being shaped by our appraisal of our real options. What are we obliged to give to our partners, and what can we realistically expect in return? Thinking about sex in quasi-economic terms can help us to understand this ongoing process.

How did sex become so cheap? Regnerus puts considerable weight on contraceptives and female careerism, both of which facilitated female promiscuity. When men can access sex without proving themselves as husbands and breadwinners, many will decide not to shoulder these onerous burdens. Pornography is another factor, which does seem to reduce men’s interest in romancing (or marrying) flesh-and-blood women. In a more traditional world, everyone had strong inducements to get and remain married. Today, outside pockets of religious conservatism, marriage is no longer seen as the high road to sexual access. It is a pinnacle of relationship fulfillment and a seal of social respectability; unless and until people see those goods in the cards, they will shy away from marriage and linger in the netherworld of cheap sex.

For women, cheap sex means significant pressure to accommodate the expectations of men. In this book, we meet men who expect (usually with justification) that women will be willing to have sex with them after a single shared meal or a few drinks. We meet women who acknowledge that they would like to develop their relationships for a bit more time before getting to sex. It’s difficult, though, to swim against the tide of male expectation. Many women spend years hopping from one disappointing relationship to the next, while marriage lingers on the ever-receding horizon.

Men have an easier time achieving their relationship goals. Whether he is looking for marriage, medium-term companionship, or just a lot of low-commitment sex, a resourceful man can likely find what he seeks. A cheap-sex market is a man’s market, in the sense that men’s expressed preferences are more often fulfilled than women’s. We shouldn’t make the mistake of thinking, though, that cheap sex promotes real thriving in men. Although women are more likely to want expensive sex, many men sorely need it to push them towards healthy and productive life habits. Marriage is also riskier for men nowadays, especially since modern women tend to have (sometimes unreasonably) high expectations for the quality of their marital relationships. Years of youthful promiscuity are poor preparation for that kind of test, and divorce tends to have a significantly negative impact on men’s health and happiness.

Is there an exit from this grim world of loveless copulation? Diagnosis is not really the focus of Cheap Sex, but it’s clear enough that Regnerus sees a more traditional breadwinner-and-homemaker marital model as the obvious alternative to our male-centric dating market. When both sexes have something valuable to contribute to the sexual exchange, long-term commitment will be a good deal for all concerned. But that’s not likely to happen unless women pull back somewhat from the labor force, restrict men’s sexual access, and force would-be lovers to woo them with promises of fidelity and material support. Regnerus doesn’t see this happening anytime soon, so his last chapter is devoted to gloomy predictions of more of the same for the foreseeable future.

Might not this be pushing the “exchange” analysis beyond its reasonable limits? When we get to the grim predictions, I start worrying that Regnerus may be reducing culture to less than it really is. That’s interesting, because I suspect that he and I would mostly want the same things when it comes to sociological trend lines. We might disagree about the extent to which sociology walks hand in hand with solid moral analysis concerning relations between the sexes.

As a Catholic and a marriage traditionalist, I love expensive sex. Sex should be expensive, because it’s very significant, socially, psychologically and morally. When we treat sex as a triviality, people get hurt. Having said that, I doubt whether “market-based” sociological analysis can really lay the groundwork for a more equitable sexual and social world.

The problem can be explained rather nicely using the exchange model itself. Insofar as we’re viewing sex as a mutually-beneficial exchange between self-interested agents, who’s to say that both parties come to the table with an equally strong hand? Isn’t it possible that nature herself has put self-seeking men in a better position to advance their personal interests?

There are plenty of reasons to believe that this might be the case. Let’s grant that men have a higher sex drive, while women have unique physical and psychological vulnerabilities reflecting their orientation towards childbearing. The result is that each sex has something to offer in a sexual exchange. Men, though, are physically stronger, while women shoulder a far more onerous reproductive burden. In a market driven by self-interest, man can surely turn these imbalances to his advantage in myriad ways, demanding compensation for his social contributions while taking the woman’s largely for granted. Woman’s unique contribution to civilization has in a sense been “assigned” by nature herself, so her negotiating position is weaker. She can try to bolster it by restricting sexual access, but is that tool really potent enough to compensate for men’s other advantages? A man may buy a cow for the milk, but cattle are not respected citizens.

In the financial world, parties with unequal holdings quite regularly enter into mutually-beneficial exchanges. However, the inequities of the original position tend to be reflected in the outcome, and the same may be true here. It seems entirely possible to build a stable society in which men extend certain essential protections to women, while allotting themselves a notably disproportionate share of available goods (which might include material pleasures, personal liberties, fulfilling opportunities, and social respect). That arrangement might be genuinely beneficial for women in comparison to (say) a Hobbsean state of nature, while still seriously failing to respect their true worth as rational beings, created in God’s image.

We shouldn’t fault Regnerus for failing to address moral questions that go well beyond the methodological constraints of his discipline. At the same time, we should be wary of amoral theories that try to explain a little too much. If we agree that modern men and women aren’t what they should be, the obvious next step is to determine what men and women should be. We won’t achieve that just by collating everyone’s expressed preferences. People often want things that aren’t good for them, especially when it comes to sexual appetite.

Despite the sad state of modern romance, men and women still want to be together, just as they always have. It may be naïve, though, to expect that healthy relations can be established without the application of any moral principles. The gulf between Mars and Venus can ultimately be bridged only when each is willing to sacrifice, for the other and for the children who are the natural fruit of sexual union. Romantic love will only flourish when we accept the fundamental truth that sex is never really cheap.

Rachel Lu is a Senior Contributor at The Federalist and a Robert Novak Fellow.