C.S. Lewis’s wife, Joy Davidman, died of bone cancer on July 13, 1960. The next day, the famous author wrote a letter to Peter Bide, the priest who had married them, to tell him the news.

“I’d like to meet,” Lewis writes, suggesting the two grab lunch sometime soon. “For I am—oh God that I were not—very free now. One doesn’t realize in early life that the price of freedom is loneliness. To be happy is to be tied.”

When it comes to romance, Americans are freer than they’ve ever been. Freer to marry, freer to divorce, freer to have sex when and with whom they like with fewer consequences, freer to cohabitate without getting married, freer to remain single, freer to pursue open relationships or polyamory.

Mark Regnerus, a sociologist at the University of Texas at Austin, thinks a lot about the price of human relationships. His new book, Cheap Sex, is all about how the modern dating scene has been shaped by sexual economics, a theory which sees human mating as a marketplace. His idea, as you might suspect from the title, is that sex is not as costly to access as it once was—in terms of time, effort, and risk. Contraception makes sex less risky; online dating platforms make it more accessible. If that doesn’t work out, there’s always porn, which requires next to no effort to find. These factors, Regnerus argues, “have created a massive slowdown in the development of committed relationships, especially marriage.”

Marriage rates have indeed plummeted among young adults, to the point that a demographer cited byRegnerus estimates that one-third of people currently in their early 20s will never get married. But another new book about modern relationships, Eli Finkel’s The All-or-Nothing Marriage, contends that while “the institution of marriage in America is struggling ... the best marriages today are better than the best marriages of earlier eras; indeed, they are the best marriages that the world has ever known.”

Because marriage for many is no longer a gateway to adulthood, but rather an optional “capstone,” it’s held to a higher standard. Regnerus asserts that modern mating dynamics make it hard for people to find a relationship that seems worth committing to; Finkel argues that when marriages manage to live up to today’s lofty expectations, they can be extremely fulfilling. One may be more optimistic than the other, but both show how increasing romantic freedom has changed romance itself.

Regnerus’s description of sexual economics relies on a stark division of gender roles: Men provide the demand and women are the supply. There is a long history of what he calls the “exchange relationship,” in which women control men’s access to sex. In order to get it, men bring to the table resources, commitment, and fidelity.

In previous eras, this exchange was effective at producing marriages (though it also went hand-in-hand with strict sexual mores and women’s subjugation). But now that sex before marriage and sex outside of relationships is common, safe, and less stigmatized, men don’t have to work as hard for it, according to Regnerus. So they ghost and flake and dither about committing to one person. Many women don’t need what resources men have to offer, anyway; they have their own. But men have more power in the mating market in this model, which leads to women also embracing, or at least going along with, cheap sex and some of the rude behavior that comes with it.

Regnerus doesn’t talk much about LGBT relationships, except to say that these market dynamics might make women more likely to “experiment with same-sex relationships,” to circumvent the problem of noncommittal men. He also writes that because there is no gatekeeper in gay men’s relationships, they are less likely to be sexually monogamous.

When it comes to heterosexual relationships, Regnerus sums up his theory like this: “It’s not that love is dead, but the sexual incentives for men to sacrifice and commit have largely dissolved, spelling a more confusing and circuitous path to commitment and marriage than earlier eras.”

This all smacks strongly of gender essentialism. Regnerus’s underlying premise is sound: Many studies have found that, on average, men want sex more than women, and women value having sex in the context of commitment more than men do (though of course individuals differ). Still, throughout the book, Regnerus takes this theory pretty far. He sounds a bit like your proverbial grandma cautioning that a man will never buy the cow if he’s getting the milk for free.

If the modern mating market has made people more isolated, shouldn’t the value of a present and proximate companion increase?

Regnerus writes about one woman who would sometimes have casual sex with men she didn’t like that much and who felt frustrated because she wasn’t finding men she did like: “She wishes to be a free rider—in this case, to find a good man—without contributing to the kinds of normative relationship behavior that make men better. It won’t work. It can’t work.”

He goes on: “In the domain of sex and relationships men will act as nobly as women collectively demand. This is an aggravating statement for women to read, no doubt. They do not want to be responsible for ‘raising’ men. But it is realistic.”

Even under a theory that believes women, through sexual gatekeeping, control how relationships unfold, it’s quite something to imply that men do not have responsibility for contributing to norms around how romantic partners should treat each other.

Regnerus also argues that the easy availability of sex makes men less motivated in their professional lives, because they don’t need to become successful, i.e., marriageable, to woo women to their beds. While this may sound dubious, there is an established precedent for this theory in the field. Regnerus quotes the famous psychologists Roy Baumeister and Kathleen Vohs, who write that “giving young men easy access to abundant sexual satisfaction deprives society of one of its ways to motivate them to contribute valuable achievements to the culture.” Still, it seems extreme to suggest that men need to be dragged by the dick into being productive citizens.

Overall, sexual economics discounts the other things men and women have to offer each other—besides sex and “resources” and commitment. Am I naïve to think that companionship and attention should have some place in this equation? If the modern mating market has made people more isolated, and if smartphones and other technology are increasingly mediating human relationships and driving us to distraction, shouldn’t the value of a present and proximate companion increase?

It is a truth universally acknowledged that a single man in possession of a smartphone will swipe right on basically everyone.

Still, there is a lot in Regnerus’s analysis that is uncomfortably astute. He’s right that it can be hard to escape these old gender dynamics when dating, especially online dating. Popular dating apps put women in the position of gatekeeping, whether deliberately or not. It is a truth universally acknowledged that a single man in possession of a smartphone will swipe right on basically everyone. This forces women to be choosier about who they say yes to. Even if they also swipe with abandon, they end up with more matches to sort through—yet more gatekeeping. On Hinge and OkCupid, which don’t require a mutual opt-in before people can send messages, women’s inboxes are deluged with men whom they must then sort through. Bumble just went all-in and made gatekeeping a selling point: Women have to message men first, putting them in control of who has access to their attention.

While Regnerus believes that the “cheap sex” mating market gives men the upper hand in relationships, he notes that after spending a long time in the market, men and women alike grow frustrated and exhausted. This is something I’ve found in my own reporting as well—that prolonged use of dating apps often leads to burnout and ambivalence. “Online dating,” Regnerus writes, “forces participants to play by its rules.” And many find that being able to hyperefficiently move through romantic options doesn’t actually make it easier to find a relationship.

This is only further complicated by the fact that what Americans want from their relationships is radically different than it’s been for most of history.

In The All-or-Nothing Marriage, Finkel, a professor of psychology at Northwestern University, traces the history of the institution over what he sees as three thematic eras. For a very long time, people married for pragmatic reasons. Most of the clothing, food, and other goods a family used were produced by the household itself, so an eternal bachelorhood would be a serious liability. People needed the labor of a partner—and often multiple children—to survive.

Things eventually became less dire, and people started marrying for love. Finkel dates that transition to around 1850, but notes that it was a shift that took place over centuries. In contrast, the transition from love-based marriages to the current era of what Finkel calls “self-expressive” marriages only took about 15 years, thanks to the counterculture shake-ups of the 1960s and 70s. During those years, the second-wave feminist movement pushed back against breadwinner/homemaker marriages and helped women earn more individual freedom. Meanwhile, concepts like “self-esteem” and New-Agey “self-discovery” found footholds in the culture.

What Americans want from their marriages nowadays, Finkel argues, is love, yes, but also someone who will give their lives meaning, and make them into the best versions of themselves. “Marriage has a self-expressive emphasis that places a premium on spouses helping each other meet their authenticity and personal-growth needs,” he writes. “The pursuit of self-expression through marriage simultaneously makes achieving marital success harder and the value of doing so greater.”..

(Read the full article by Julie Beck here)