DUCKWORTH: We’re animals. Haven’t you ever heard of Darwin?
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DUCKWORTH: I’m Angela Duckworth.
DUBNER: I’m Stephen Dubner.
DUCKWORTH + DUBNER: And you’re listening to No Stupid Questions.
Today on the show: why are we having less sex than we used to?
DUCKWORTH: I think even masturbation is down.
DUBNER: I don’t have that number handy. I’m sorry.
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DUBNER: So Angela, this is the third episode of our Seven Deadly Sins series. We’re approaching the so-called sins in the order we chose, not the way the Catholic Church listed them. We started with sloth, then we solved gluttony. And now, it’s time for everyone’s favorite of the seven deadly sins, which is lust.
DUCKWORTH: It is a favorite.
DUBNER: I’ve read in a variety of sources that in the U.S. but many, many other countries as well, people are just having less sex. Period. Full stop. And I’m curious why you think that is based on your knowledge of the psychological research, based on this project you are working on now, this new book about self-control. And I’m especially curious whether you think the decline in sex may be due to the easier availability of substitutes for sex, including pornography, or whether maybe something totally different is going on.
DUCKWORTH: I have been thinking about this for a little while because I was thinking about things that changed during the pandemic that might still be with us, you know, with social distancing and quarantining. But it turns out most of the research was done actually before the pandemic, so you don’t need to have a pandemic to stop having sex. I’m thinking about one paper by Jean Twenge called “Declines in Sexual Frequency among American Adults, 1989 to 2014” — clearly before the pandemic. If this is a secular trend, as it’s called — a trend that extends for an entire population over years — it might actually say something more general about the way we live today. In the paper that I just mentioned, the conclusion is that the decline was not linked to longer working hours or increased pornography use. But I do wonder about porn as a substitute good for sex and even just for intimacy, like a romantic relationship with another human being.
DUBNER: So much to discuss and unpack here.
DUCKWORTH: So much to undress here, so to speak.
DUBNER: I’m reading from the Twenge study. After they write that it does not appear that if you measure inputs of pornography or longer work hours, that those are what’s driving the lower sexual frequency. They do say possible reasons that may account for the decrease are the increase in entertainment options like social media and video streaming and the increase in depression. I’ve also read elsewhere that pharmaceuticals that are meant to treat depression, anxiety, etc., may decrease sex drive.
DUCKWORTH: I do know that when you are in a depressed state, there’s this feature, anhedonia, the inability to experience pleasure from food or from music or from the sorts of things that you used to take pleasure in. So that, to me, would be probably at least part of the story. You’re depressed or you’re anxious, you don’t feel like having intercourse. These authors have a good point that — when I think, “What’s crowding out actual sex?” I think porn. But just being on Facebook for hours or watching old episodes of Friends, you know, that also could crowd it out. Because it’s occupying your time and also maybe feeding your desire for social connection. So anyway, it’s not just porn that could be crowding out sex.
DUBNER: I do remember reading years ago about a paper, and I think the paper was disputed to some degree, but the paper argued that the increase in the availability of pornography did help reduce sexual assault crimes.
DUCKWORTH: Oh, interesting. Because it was a substitute good?
DUBNER: Yeah, that’s an argument. And then, you know, economists do like to talk about substitute goods generally.
DUCKWORTH: They love talking about substitute goods
DUCKWORTH: There is this research study that was published in 2016. It’s called “Pornography and the Male Sexual Script: An Analysis of Consumption and Sexual Relations.” And it’s from the Archives of Sexual Behavior. And what these authors suggest is that actually what pornography gives you is a script for what sex is supposed to be. They call this “cognitive script theory” — you watch these things, and you’re like, “Oh, that’s what it’s supposed to look like. That’s what I’m supposed to feel.” And I can imagine how that could be true, especially because sex is something that you don’t get to watch a lot of people do in general.
DUBNER: Speak for yourself. I’ve got a telescope. I live in New York City. It’s, you know, windows just all over.
DUCKWORTH: Maybe outside of New York — Anyway, what they go on to say, these authors — and I’ll quote them directly: “Cognitive script theory argues… The more a user watches a particular media script, the more embedded those codes of behavior become in their worldview, and the more likely they are to use those scripts to act upon real life experiences. Then they go on to say that they surveyed close to 500 college men — these are young men aged 18 to 29 — all in the United States.
DUBNER: Wow. That’s kind of old to be in college, isn’t it?
DUCKWORTH: Well, I will say, most students don’t graduate in four years from four year schools. They stretch it out. So anyway, they asked them questions about the rate at which they use pornography, and they asked them about their sexual preferences and their concerns. And what they find is that the more pornography a man watches, in their survey, at least, the more likely he was to use it during sex — to request particular sex acts of the partner, to conjure images of pornography during sex to maintain arousal, have concerns about his performance and body image from those scripts that he saw. So the study had one other finding that I think is worth thinking about, even though it’s just one survey study. “Higher pornography use was negatively associated with enjoying sexually intimate behaviors with a partner.” So not a pretty picture of porn.
DUBNER: I’m reading here something that I think is related to the paper that you’re describing. Debby Herbenick, the principal investigator of the National Survey of Sexual Health and Behavior, says that increases in rough sex may be contributing to declines in overall sex — the thinking being that for sexually active people under 30, there’s been an increase in consensual choking and strangling during sex, which I gather, although it doesn’t say it right here, is derived from the consumption of pornography. That’s the behavior that’s modeled. And which, may frighten some people and cause them to opt out. In other words, the model of sex portrayed in some pornography is a model of sex that people see and say, “Oh, I’d rather have zero sex. Not for me.”
DUBNER: So there was another example having nothing to do with pornography or sex that showed that violence declined during the periods where violent movies were debuting, the idea being that either the people who might be shooting other people are actually watching the violent movie at the time, so they’re too busy to go shoot people. Or it could be that it does serve as a substitute.
DUCKWORTH: Do you happen to know whether in the long-term violent movies, violent video games, increases or decreases violence in a society?
DUBNER: I have read a lot of research on this topic, going back to the invention of TV. Because if you think about it, TV came along not too long before a really, really big crime spike in the U.S.
DUCKWORTH: I did not know that. What decade are we in? I have no idea when TV was invented.
DUBNER: The year that pops into my mind is 1948, but it was more gradual than that. It appeared in some places and in some doses, but then it started getting more and more popular. And certainly, by the ’50s it was almost universally popular in the United States. And then the crime spike really began to happen in the 1960s. And there were many, many, many potential inputs to that rising crime. But one theory was that television presented a set of behaviors that might encourage crime. And then, there were others that argued exactly the opposite. But in terms of your overarching question, I think it has yet to be answered satisfactorily
DUCKWORTH: That is interesting. I mean, I do want to say this, as a psychologist: human beings are always learning vicariously. More than any other animal, we learn by watching what other people do. So which way does the causal arrow go? How big is the causal arrow? I don’t know. But it is true that we internalize, and we compare all the time, when we watch other people.
DUBNER: If you just think about the last 100 years, just in the United States, the way that sexual norms have changed is really remarkable. Between 2009 and 2018, the proportion of adolescents reporting no sexual activity, either alone or with partners, rose from 28.8 percent to 44.2 percent among young men, and from 49.5 percent to 74 percent among young women. That’s a massive decline in recent years. That, however, is an exact opposite of what happened 50, 60, 70 years earlier. We wrote about this a little bit in SuperFreakonomics. We were writing about prostitution, actually, as a sort of industry that we studied from the economic and social perspectives. If you look back to the middle of the 20th century, it turns out that among men who were born between 1933 and 1942, at least 20 percent of them, the first time they had sexual intercourse, it was with a prostitute. So one out of five men born in that period, their first sexual intercourse was with a prostitute, the argument being that there wasn’t as much sex available from non-prostitutes as there would be later. Now, if you think about the same man 20 years later, born in, let’s say, the ’50s or ’60s, the shift in sexual mores created a big change in what you might call a supply of unpaid sex, consensual sex that may have happened before marriage or outside of marriage. And in that generation, only 5 percent of men lost their virginity to a prostitute. And it’s not that people were having less sex. In fact, let’s see, more than 70 percent of the men in his generation had sex before they married, compared to just 33 percent in the earlier generation. But then, in the last couple decades, we see this big drop. I do wonder if it could be that more and more people in the last 30 years have come to think that what used to be called casual sex, just sex for the sake of sex and having fun — I wonder if just more and more people, men and women, have come to think that that’s not a good idea.
DUCKWORTH: That may be true, but I believe the statistics also show that sex within married couples —
DUBNER: Is up.
DUCKWORTH: No, it’s down, I think. The data suggests that married couples are having less sex than they used to.
DUBNER: Everybody’s having less sex, but the share of people having sex within marriage is higher relative to the share of people having sex outside of marriage than it used to be.
DUCKWORTH: Totally agree. But I’m just saying like, think of your married friends. Statistically, on average, they’re having less sex than married people did X number of years ago, which to me was surprising. And I think even masturbation is down.
DUBNER: I don’t have that number handy. I’m sorry. Let me get the telescope back out this evening, and I’ll let you know.
DUCKWORTH: Yeah. I‘m not an expert on this, but you just mentioned that article by Debby Herbenick and one of the findings — this is a survey of teenagers — was that adolescents are reporting less I think the technical term is “solo masturbation.” There might be other kinds.
DUBNER: So that may be among adolescents. I’m looking at something here that says, from 1992 to 2014, the share of American men who reported masturbating in a given week doubled to 54 percent. And the share of women more than tripled, but from a low base to 26 percent.
DUCKWORTH: It could be teens versus adults. Who knows? But we do know that these trends in who’s having sex, how much sex are they having, etc. — things are shifting. I have to say, when I grew up, and even when I was in college, I was a bio major.
DUBNER: Bio majors have so much sex, I understand.
DUCKWORTH: Oh, on the contrary, Stephen.
DUBNER: I mean, it’s homework, really.
DUCKWORTH: Think pre-med. Does that help? Yeah, not very exciting lives being lived. But I remember thinking intuitively that there are so many hardwired things about an animal, including a person. So, the kind of trends that we’re talking about — and frankly the plurality of gender identities and so forth — I think the lesson it’s taught me is that wow, there is a lot more plasticity, there’s a lot more shaping from culture, society, and norms, the way we think about things than I would’ve expected. Like, I don’t know that I would’ve believed these trends about sex going down and, you know, people going on social media instead of having intercourse with each other. I was like, “Oh, are you kidding? We’re animals. Haven’t you ever heard of Darwin?” But people change or society changes.
DUBNER: I want to go back to the piece of society changing that I talked about before, what’s sometimes called the sexual revolution, or the embrace — among many people, at least — of what was called casual sex. I think it may be that more and more people would decide that it’s not a good idea because sex is such an intense and intimate experience that it shouldn’t be reduced to what you might call a casual interaction. It’s just more meaningful than that, whether it’s inside or outside of a relationship. And it’s almost as if the sexual revolution for both men and women decoupled sex from love and that the past decade or two we may have seen more of a conscious recoupling, if you will. Just a theory. I have no idea if that’s true. I also wonder, if we look at the baseline numbers of the decline in sexual activity, when sex in a bad form is in the news so much for so long with the Catholic Church scandal, with so many instances of sexual abuse and harassment, including the Me Too movement, but well, well before that — I wonder if, to some degree, it’s given sex a bad name, made it seem as if it’s usually nasty or unnatural and an activity that’s, you know, almost inherently based in conflict or inequity. And if that’s the case, personally, I think that’s a shame.
DUCKWORTH: My husband Jason sent me an op-ed from The New York Times that was published I think the day before Valentine’s Day. The title is some version of “Have More Sex, Please!” And the perspective offered — provocative — is that we should be having more sex. And feel free to disagree because I take your point about the recoupling between sex and love and that it’s not just a physical urge. But the argument was made, I think, persuasively that when you have this most intimate of relations with a real person — like, we’re not living just by watching flickering images on our phone vicariously. And it’s hard to think of an activity which is more like in the here and now. Real. It’s not the metaverse. And the recoupling isn’t necessarily at odds with that. I mean, one of the arguments that’s made in this op-ed is more broadly than sex, this might be a leading indicator of American loneliness. We’re more and more staring at our phones, swiping, scrolling, but we’re more and more isolated from each other. So you could think of sexual relations as being like the extreme, as being like really not completely by yourself. I did find that compelling. I do worry about people like being in their apartments, having their food delivered, being on their phone, watching other people have adventures or dramas, and being increasingly disconnected. It’s like a version of the Bowling Alone theory from the sociologist Robert Putnam.
DUBNER: Sexing Alone.
DUCKWORTH: The Bowling Alone book was about how bowling leagues were going down and solo bowling was going up. That was written how many years ago? At least 15 or 20?
DUBNER: I think there’s an interesting parallel you’re bringing up here. First of all, I don’t think many people actually go bowling alone. I think they choose to not bowl. I love the title, but —
DUCKWORTH: It’s a great title.
DUBNER: I see very few people bowling alone. I think they just do activities other than bowling. But, his argument is that social trust is the glue that keeps a society healthy and that by doing more and more things on our own — I mean, another example I think of is back in the old days, like the early-middle 20th century, people from New York City, when they scraped up enough money to get out of the city for the summer, they would go to these cabin resorts or hotels in the Catskills.
DUCKWORTH: My mom was a waitress at one of those, by the way.
DUBNER: Oh, no kidding. And that was a very big community social thing. Now, people who have the means, they tend to go to their own little vacation home. And I think about that a lot, the way that we’ve chosen to diminish our circles, and I think there are some benefits to that. People like privacy. People like being with their closest loved ones and choosing who they have dinner with, rather than sitting with 12 other people that you may not know. But Putnam was making the argument that we lose a lot culturally.
Still to come on No Stupid Questions, Stephen and Angela discuss the consequences of the decline in sex.
DUCKWORTH: From the very beginning, I remember having misgivings about lust being a sin.
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Now, back to Stephen and Angela’s conversation about lust.
DUBNER: I wonder what you think, Angie, may be the consequences of so much less sex. We should say some of the effects are plainly positive. The rate of teen pregnancy has gone way, way, way down.
DUCKWORTH: Way down.
DUBNER: But the overall fertility rate has also gone down a lot, and that’s typically not a good thing for society. So when you think about the downward trend in sexual activity, what do you think are the consequences of that? How is it changing us?
DUCKWORTH: I probably worry more about the things that are correlated with sex than I do about sex itself.
DUBNER: Like corned beef, or what are you talking about that’s correlated with sex?
DUCKWORTH: Not a side of corned beef.
DUBNER: That’s what George Costanza was after. I don’t know if you recall. He wanted to have sex while eating like a pastrami sandwich and watching the Yankees on TV. That was his sex trifecta.
DUCKWORTH: Oh, I missed that episode. I did not catch that Seinfeld allusion. Well, I found the op-ed of which I spoke, the one that my husband wrote to me with the subject line, “I like this op-ed for many reasons.” I think he was a little tongue in cheek there.
DUBNER: Was this his little Valentine’s note to you? Like, “Hey, honey, let’s get it on.”
DUCKWORTH: Well, yes, it was the day before Valentine’s Day.
DUBNER: “Let’s do our patriotic duty.”
DUCKWORTH: Maybe so. You know, the title of this op-ed is “Have More Sex, Please!” And the author is a writer who covers sex and culture named Magdalene Taylor. And at least according to her, there are numerous physical benefits. Apparently you have better sleep. There is evidence that it lowers blood pressure. It’s good for your heart. It’s a good stress reliever. But I think about the things that are correlates of having sex that are maybe even more important. In general, I think the fact that you’re having sex with another person suggests that you have some kind of relationship, right? That you’re like having dinner with somebody, you’re talking to somebody about your day. And, the point has been made, that maybe the epidemic we should all be worrying about and maybe one of the worst things about Covid was loneliness. And not to undermine sickness and death from Covid. But, just the isolation. I mean, I remember — and this has nothing to do with sex — but, you know, my father passed away in April, the first month, at least for the United States, of the Covid-19 pandemic. And my mother had been living with my father in this nursing home. And not only at his death, but also for the next two-plus years, like couldn’t really see her. And because of quarantine and so forth, my 80-something-year-old mother was just like completely socially isolated. So I guess I worry more about that kind of thing than the lack of intercourse, per se.
DUBNER: Yeah, I think that’s a really good point. You know, I would love, Angela, to hear from listeners. Why do you think fewer people are having sex? We’ve put forth some research-based assumptions. I put forth a theory that’s based in nothing other than thinking and opinion. But I’m really curious to know why our listeners think fewer people are having sex. So if you have something to contribute that we can maybe play on a later episode, send us a voice memo. Just use your smartphone to record. Record in a nice, quiet place. Keep it relatively short. Include your name and send that to us at firstname.lastname@example.org. You know, Angela, I’m thinking now that we have gotten to the end of our third installment of the Seven Deadly Sins series, on sloth, our first one, we asked whether basically one should be more industrious, and you said yes, and I said not so fast. So we were kind of split on that. On gluttony, we agreed.
DUCKWORTH: We were like, oh my gosh, ultra-processed food is horrible.
DUBNER: And that we should find ways to consume less. With lust, it feels like we’re both saying that people should just get out there and have a lot more sex, but presumably be somewhat selective. Would that be your advice?
DUCKWORTH: Well, I think we’re voting for love, right? Like we’re voting for meaningful sex, wherever and whenever possible. You wanted to recouple love with sex, and I’m on that team.
DUBNER: I didn’t necessarily say I wanted that. I said that was my theory that maybe would explain why people are having less sex. But to be fair, I like the idea of recoupling sex and love. I absolutely do. I think there’s been a lot of damage done by the uncoupling. I think there are massive really — you know, an economist would call them negative externalities of people pursuing sex for the sake of sex. I mean, I personally know several people, men, who have ruined lives — their own lives and lives of their families and other people — by the pursuit of sex that they literally could not control. And so, if what we’re seeing is a decline overall in sexual activity because some people have got that pursuit under control, I think that’s a positive step.
DUCKWORTH: But I don’t think that’s driving the secular trend. I don’t think it’s like sex addicts are going down, and then the whole population’s going down. I will say this. From the very beginning, I remember having misgivings about lust being a sin.
DUBNER: I remember in our first conversation, now. You said you didn’t think that should even belong in the list of sins, and I thought, are you bonkers? Only a woman would say that, by the way, because if you’re a man, and you’ve ever been around a man —.
DUCKWORTH: I think maybe there is a gender difference here. I’m like, “Well what impulse are you talking about that’s so hard to—? How could you possibly let that crowd out your desire for coffee or wanting to read a good novel?”
DUBNER: But as it turns out, even a lot of men are susceptible to crowding out from video games and social media and movies and so on, apparently!
DUCKWORTH: Apparently so. But nevertheless, when we put this on the scale when we asked people in focus groups, we did find gender differences on the scale. So we’ll see what happens when we survey No Stupid Questions listeners, but I do think there are many men and certainly some women as well, who would say that the drive to feel these feelings, either by yourself or with other people, it can get you into trouble. And that’s the definition I think for all of these sins.
DUBNER: Wait. You’re saying that you used good academic research dollars, some of which are federally and taxpayer-funded, to conclude that sexual appetite is actually a real thing.
DUCKWORTH: Well, that was not the point of the study. And by the way, no tax dollars at work.
DUBNER: Amazing finding down there at University of Pennsylvania. Good work.
DUCKWORTH: No, that was not the point of the study. But my point is that when you do focus groups, people say, just spontaneously like, “This is a problem for me,” because we ask them about their own lives.
DUBNER: And we should say, if you, listening now, want to take the survey that Angie just mentioned — this is a Seven Deadly Sins survey that she put together and is running mostly for our fun and edification — the survey is linked in the show notes of this episode. It is also on the No Stupid Questions website. The link there will take you to a University of Pennsylvania site where Angie is presenting this survey for anybody to take so you can really learn about yourselves.
DUCKWORTH: It’s not for research, it’s just for you. And, the lust items, none of them are X-rated. I don’t even think any of them are R-rated.
DUBNER: So Angela, has this conversation today made you lustful? Are you going to run home and have sex with Jason?
DUCKWORTH: I refuse to answer that question, Stephen.
DUBNER: Really? On the grounds that it may agree with your sentiment?
DUCKWORTH: Yeah, exactly. I was like, am I taking the fifth?
DUBNER: Happy late Valentine’s Day then.
DUCKWORTH: I will say this. I’m really glad I married Jason Duckworth.
This episode of No Stupid Questions was produced by me, Katherine Moncure, with our production associate, Lyric Bowditch. And now, here’s a fact-check of today’s conversation.
In the first part of the episode, Stephen says he thinks the TV was invented sometime around 1948. The TV was actually first demonstrated in public in 1927 by Scottish engineer John Baird. Then, Stephen says that married people have more sex than singles and that the gap has grown over time. But, Jean Twenge’s 2017 paper “Declines in Sexual Frequency among American Adults, 1989-2014” says that the “marriage advantage” has shrunk over time, not grown. Finally, Stephen says that Seinfeld character George Costanza’s “sex trifecta” is having sex while eating a pastrami sandwich and watching the Yankees on TV. While George’s trifecta does include sex, pastrami, and TV, he doesn’t say anything about the Yankees.
That’s it for the fact-check.
Before we wrap today’s show, let’s hear some of your thoughts about last week’s episode, in which Stephen and Angela tackled the sin of gluttony with a discussion of processed food:
Gideon ETRA: Hello, Stephen and Angela. This is Gideon from New York. One of the ways I have discovered to control excess is to apply some of the dietary principles of Ayurveda, the ancient Indian science of health and longevity. Ayurveda recognizes that we need all six tastes — sweet, sour, salty, bitter, astringent, and pungent — to be represented in a meal in order for us to feel sated. I would suggest that if more Americans tried to incorporate all six tastes in a given meal, they would feel truly sated. After all, processed foods have mostly one or two tastes, typically sweet and salty.
Mike FOLEY: Hi Angela and Steven. My name is Mike Foley and I live in Richmond, Virginia. And I love all things processed. There’s some really good food out there and would ask you to consider the tater tot. Yummy! Thanks for the show.
That was, respectively: Gideon Etra and Mike Foley. Thanks so much to them and to everyone who sent us their thoughts. And remember, we’d still love to hear why you think people are having less sex these days. Send a voice memo to NSQ@Freakonomics.com. Let us know your name and whether you’d like to remain anonymous. You might hear your voice on the show!
Coming up next week on No Stupid Questions: Stephen and Angela discuss the power of wrath.
DUCKWORTH: I was so mad that I ripped apart the turkey sandwich, covered in mayo and everything, and I just flung it into all corners of the room.
That’s next week on No Stupid Questions.
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No Stupid Questions is part of the Freakonomics Radio Network, which also includes Freakonomics Radio, People I (Mostly) Admire, and Freakonomics, M.D. All our shows are produced by Stitcher and Renbud Radio. This episode was mixed by Eleanor Osborne, with help from Jeremy Johnston. We had research help from Rebecca Lee Douglas and Dan Moritz-Rabson. Our executive team is Neal Carruth, Gabriel Roth, and Stephen Dubner. Our theme song is “And She Was” by Talking Heads — special thanks to David Byrne and Warner Chappell Music. If you’d like to listen to the show ad-free, subscribe to Stitcher Premium. You can follow us on Twitter @NSQ_Show and on Facebook @NSQShow. If you have a question for a future episode, please email it to email@example.com. To learn more, or to read episode transcripts, visit Freakonomics.com/NSQ. Thanks for listening!
DUBNER: Record in a nice quiet place. Include your name and number. Sorry —
DUCKWORTH: Include your name and number.
DUBNER: And some photos. We’ll see which way we swipe.
- Debby Herbenick, principal investigator of the National Survey of Sexual Health and Behavior and director of the Center for Sexual Health Promotion at Indiana University Bloomington.
- Robert Putnam, professor emeritus of public policy at Harvard University.
- Jesse Shapiro, professor of economics and business administration at Harvard University.
- Magdalene Taylor, writer specializing in subculture, sex, and the Internet.
- Jean Twenge, professor of psychology at San Diego State University.
- Seven Deadly Sins Survey, by No Stupid Questions (2023).
- “Have More Sex, Please!” by Magdalene J. Taylor (The New York Times, 2023).
- “Changes in Penile-Vaginal Intercourse Frequency and Sexual Repertoire From 2009 to 2018: Findings From the National Survey of Sexual Health and Behavior,” by Debby Herbenick, Molly Rosenberg, Lilian Golzarri-Arroyo, J. Dennis Fortenberry, and Tsung-chieh Fu (Archives of Sexual Behavior, 2022).
- “People Have Been Having Less Sex — Whether They’re Teenagers or 40-Somethings,” by Emily Willingham (Scientific American, 2022).
- “The Long-Term Decline in Fertility—and What It Means for State Budgets,” by Jeff Chapman (Pew, 2022).
- “Pornography and Sexual Aggression: Can Meta-Analysis Find a Link?” by Christopher J. Ferguson and Richard D. Hartley (Trauma, Violence, & Abuse, 2022).
- “Why Are Young People Having So Little Sex?” by Kate Julian (The Atlantic, 2018).
- “Declines in Sexual Frequency Among American Adults, 1989–2014,” by Jean M. Twenge, Ryne A. Sherman, and Brooke E. Wells (Archives of Sexual Behavior, 2017).
- “Pornography and the Male Sexual Script: An Analysis of Consumption and Sexual Relations,” by Chyng Sun, Ana Bridges, Jennifer A. Johnson, and Matthew B. Ezzell (Archives of Sexual Behavior, 2014).
- “Does Movie Violence Increase Violent Crime?” by Gordon Dahl and Stefano DellaVigna (The Quarterly Journal of Economics, 2009).
- “Chapter 1: How Is a Street Prostitute Like a Department-Store Santa?” by Stephen Dubner and Steve Levitt (SuperFreakonomics, 2009).
- Bowling Alone, by Robert D. Putnam (2000).
- “The Fracking Boom, a Baby Boom, and the Retreat From Marriage,” by Freakonomics Radio (2017).
- “What Can Economists Tell Us About Teenage Sexual Mores?” by Stephen Dubner (Freakonomics Blog, 2010).
- “The Blood,” Seinfeld season 9, episode 4 (1997).
- Seven Deadly Sins, series by No Stupid Questions.