More Sex is Safer Sex

I had forgotten that Steven Landsburg’s More Sex is Safer Sex (link to the 1997 NYTimes version, book here) was inspired by a paper by new Nobelist Michael Kremer. Here’s the recap:

You’ve read elsewhere about the sin of promiscuity. Let me tell you about the sin of self-restraint.

Consider Martin, a charming and generally prudent young man with a limited sexual history, who has been gently flirting with his coworker Joan. As last week’s office party approached, both Joan and Martin silently and separately entertained the prospect that they just might be going home together. Unfortunately, Fate, through its agents at the Centers for Disease Control, intervened. The morning of the party, Martin happened to notice one of those CDC-sponsored subway ads touting the virtues of abstinence. Chastened, he decided to stay home. In Martin’s absence, Joan hooked up with the equally charming but considerably less prudent Maxwell – and Joan got AIDS.

When the cautious Martin withdraws from the mating game, he makes it easier for the reckless Maxwell to prey on the hapless Joan. If those subway ads are more effective against Martin than against Maxwell, they are a threat to Joan’s safety. This is especially so when they displace Calvin Klein ads, which might have put Martin in a more socially beneficent mood.

If the Martins of the world would loosen up a little, we could slow the spread of AIDS. Of course, we wouldn’t want to push this too far: if Martin loosens up too much, he becomes as dangerous as Maxwell. But when sexual conservatives increase their activity by moderate amounts, they do the rest of us a lot of good. Harvard professor Michael Kremer estimates that the spread of AIDS in England could plausibly be retarded if everyone with fewer than about 2.25 partners per year were to take additional partners more frequently.

And here is Kremer’s original paper (with Charles Morcom). Landsburg suggests that a subsidy for condoms would be optimal in this situation. Read the whole thing.

Addendum: I later pointed out that the Kremer model appears to fit what happened in Thailand quite well.


Medical treatments and prevention are certainly among the most contentious issues in American society nowadays.
What is the best way to provide American citizens with the healthcare they both need and deserve? How can we help our children to grow healthy and safe?

Representative Gabbard has decided to support Medicare for All, an initiative to make sure every American gets access to high quality hearhcare for free. According to her, it is time to put lives before profits.

Gabbard: In your heart, you know she is right.

I like General/War Hero Gabbard. She pisses off many of the right people.

However, why are the Dem dwarves running on fixing the dreaded health care crisis five years after passing their miraculous, single-party health care omnibus which they tell us everybody loves and is working so well?

Because the promise of "free stuff" buys votes.

Evidently, nothing is perfect. The point is, some must be done to address the health crisis America faces. Romney/Obamacare is, at best, a band-aid applied to a gangrene for lack of better instruments. Let's remember: Republicans reneged their "repeal and replace" promises.

Representative Gabbard will implement a Medicare for All plan to make sure every American can get the healthcare he or she needs.

Gabbard: A choice, not an echo.

Please tell me about the health crisis.

And, convince me why I should be screwed because of the socialist agenda. It's not about health. It's about control and power.

No, it is not. It is anout helping Americans. Representative Gabbard pointed out that it is outrageous that, in the richest nation in the history of nations, people are being bankrupted by medical bills. The solution is a unversal healthcare system.

Gabbard: In your heart, you know she is right.

That is not true at all. Those are lies the Democratic Party corrupt machine is using to try to succeded in stealing the nomination again. Remember 2016. The Democratic Party machine chose Clinton and elected Trump. Representative Gabbard is the base's real candidate.

Gabbard: In your heart, you know she is right. Visit her campaign's site:

I don't get the assumption that Martin is prone to the effects of advertising but Joan isn't; or that Joan is going to a party determined to hook up with someone, rather than pining specifically for Martin. If you want to be sexist in your assumptions, note that Joan is much more likely to be pining for a specific guy than going out for a night on the prowl. Unless rather the assumption is that Maxwell is simply a determined, very effective predator; and yet, timid Martin would be enough to stand in his way? The whole setup is simply ridiculous with gross unsubstantiated assumptions about human behavior.

Agree. The fable presented is not a good story/argument but purely circular in reasoning.

Once again, men are to blame for sluts getting STDs. C'mon Martin, man up and bang that chick!

Sex and violence: It's pervasive.

If you assume some very specific conditions, you can create a model that generates counter-intuitive results.

If you do this in the right domain, your counter-intuitive result will allow you to give your paper a scandalous title, which will generate lots of publicity and funding for you.

It doesn't matter if the finding is important, or even applicable to the real world at all.

This is purely a story about the biases driving science.

This is a very immoral lifestyle. God is watching.

Don't worry. He supports Donald Trump. Something about David and Joseph. Or so say Evangelicals.

These are also anonymous/Thiago

No, these are not.

This requires the pretty big (and I'd assume not necessarily realistic) assumption of an inelastic demand for sex among those already having sex. If the new, conservatively sexual partners are replacements for more promiscuous partners, then sure. But if it means that Joan can have sex with both Martin and Maxwell instead of just Maxwell, then, well, how is this beneficial?

If Judas had not betrayed Jesus there would be no Christianity.

If Jesus existed. Indeed, if Judas existed. They might well have done but nobody knows.

Josephus made two references to Jesus of Nazareth, about 60 years after his death. See the Wikipedia article "Josephus on Jesus".

If Jesus did not exist, the 4 evangelists wrote a story that was more than Shakesepearean in 4 different ways, based on a fiction.

Imagine if England had produced 4 Shakespeare level writers in one generation (for those who do not know what I am talking about, that is what Keats plus and Whitman plus means ---- Shakespeare level)...

That is a literary proof for the existence of Jesus that you probably have not thought of. If you have thought of it and discounted it, well, good for you. My guess is that you haven't, though.

While poor Harold Bloom said the style of the 4 was not very good, he did not read Greek as well as I do. Luke and John were at Keats level and Whitman level plus, respectively, and as for Mark and Matthew, well they were at least as good as Livy and Cicero.

The Romans had every incentive to preserve similarly well written prose narratives. Either they could not do so or chose not to do so.

Just saying.

Feel free to believe I do not know what I am talking about.

You would be wrong, but feel free to believe it, my friends.

The King James Version is very impressive writing, but I believe it was done by a committee of 70 of whom it would be very surprising if more than three or four were "Keats and Whitman plus." You have to give some credit to the Hebrew and Greek originals. Hebrew, in particular, has an alliterative rhythm that has no direct equivalent in English but the KJV somehow captures it. The heavens declareth the glory of God and the firmament showeth his handiwork. Almost Shakespearean.

Sorry, my comment was not clear. I meant that the Hebrew and Greek originals could have been created by poets of near-Shakespearean quality *without* divine inspiration, and that such people do exist from time to time. Keats, Byron, Shelley, Coleridge, Blake, and Wordsworth lived within one generation of each other in a little country of 10 million. While I believe that a historical Jesus existed, the superb quality of the writings about him is not a proof of his existence; there is also great writing about the Greek gods and goddesses.

2 Shakespeares in one generation from a small population, writing about the same human being in whom they obviously had complete trust, and 2 other writers as good as Livy and Cicero, who had the same level of trust.

If you understand the ancient world, or even if you simply understand what we know about the limits of literary talent over the small sample size of a few hundred generations from a few thousand distinct populations, that is a very persuasive argument (for either the existence of Jesus or for an otherwise almost infinitely inexplicable explosion of genius).

But I am not here to persuade you - just to evangelize you (or convert you).

If you don't care about literary genius, well, nothing I said makes real sense.

If you do, maybe it does.

Correction - 3 Shakespeare level writers (Paul being the third).

Try and imagine any English writer besides Shakespeare being capable of writing the prison letters or the letter to the Romans.

China came close with Li Po and Tu Fu, but there were an awful lot of Chinese people who liked to write over the last 80 generations.

And they were exactly the sort of people one would expect to be geniuses.
Can't say that about John and Luke and Paul - well, maybe Paul, the student of Gamaliel.

Hard to find this out on the internets, but Jani von Neumann and Kolmogorov both considered this to be a very good argument, I think.
Remember, before you defensively give an internal sneer - as so many people who read comments on the internet too too frequently do - remember, Gauss almost regretted, all his life, having chosen mathematics over the study of languages, and Gauss would have loved to know what I know ----

That John the Evangelist was a poet not of Whitman's caliber but much better than that

That Luke the Evangelist was a poet not of Keats' caliber but much better than that.

non omnes omnia possumus

cor ad cor loquitur

Thanks for reading, and please give a moment's thought to the consideration that I am not just possibly correct, but actually correct.

(I usually only post on Professor Cowen's comments, but I was seriously offended by the commenter who said "nobody Knows" on a subject on which I know a lot about ---- more than poor Bloom and poor Kolmogorov. It is not a subject about which it can be honestly said that "nobody knows" .... trust me

Neumann - not sure about him. He may have known a lot more than he let on. Nobody knows? maybe Bloom and Kolmogorov did not know, but me and Neumann ....

Two schools of thought on that.

not every day on the internet that you read a comment that includes the phrase "Gauss would have loved to know what I know"

cor ad cor loquitur

Congresswoman Hill will be leading a fact-finding delegation


You left "wide ranging and extensive" out of the description of her fact finding efforts.

I like how everything needs to be either free or banned.

"Everything not forbidden is compulsory."

Of course the alternative is that the Martins in a society (perhaps even with the implicit help of the Maxwells) instill a culture that discourages the Joans from having casual, unmarried sex with either party.

The current collective imagination is somewhat crude and limited and Martin may be cast in a comic role only.

Until he shoots up a school or mosque at which point he becomes a menace only to be solved by banning YouTube channels or anime messageboards.

Let's go get stoned. Sounds like fun.

Landsburg wrote his column in 1997, a year before a large University of San Francisco study showed that the odds of a woman contracting HIV through vaginal intercourse from an infected man is 1 in 8,000 and the odds of a man contracting HIV from a woman is even lower. The risk of contracting HIV from an infected partner through anal sex is around 1 in 100. Another University of San Francisco in 2002 showed the risk of HIV through oral sex "is a very rare event - statistically our study showed a probability of zero - and is rarer than HIV infection through receptive anal intercourse using a condom."

Given this huge disparity in risk between sexual practices, I don't see how Landsburg's argument holds up.

The risks of an infection from Maxwell are even less if he is not bisexual or an injection drug users. In today's share everything about yourself culture, Joan would probably know the former about Maxwell (and suspect the latter). She could also adjust for race. With all of this, Joan could make an informed decision.

I might add, after making her calculations, she's probably better off heading over to Baxter's apartment for an evening of playing cards.

Eh.... I badly want to see the Sure take on this. I suspect it to be both out of agreement with the OP, and correct. Though I may be surprised.

To avoid argument - I would propose an empirical test though; where we have specifically shifts from low partner to celibacy, and upwards shifts from mid-partners to higher partners, at the same time, do we see higher STD infection rates?

Progressives should frame this as an inequality issue.

Maxwell is part of the 1%. Laissez-faire sexualism has created a concentration of privilege and the rest of us are getting screwed. Or not, actually.

The solution is single-payer universal sex care. Formerly marginalized people get steady jobs with benefits, with new unions that reliably fund Democratic candidates. Progressives sweep to power in a grand coalition of incels and SJWs.

And then sex-robot automation throws everyone out of work. Ah well.

"Laissez-faire sexualism has created a concentration of privilege and the rest of us are getting screwed."

You mean, women not being forced to sleep with you hurts your feelings? Do you want a safe space?

Being forced to support (through taxes and subsidies) the lifestyles of women who have no interest in sleeping with me hurts my wallet.

When the cautious Martin withdraws from the mating game, he makes it easier for the reckless Maxwell to prey on the hapless Joan.

Can one apply the same reasoning to feminism and conclude that when feminist admonitions about "men" judging and objectifying women make sensitive men (partially) withdraw from the mating game, they make it easier for insensitive and exploitative men to prey on the hapless Janes?

No, that would be sexist.

If you don't let him cum inside your ass, you should be fine.

Bizarre. My response to Thiago shilling for Tulsi Gabbard got removed but his comments weren’t. I would understand if the whole thread was censored, but why just me? Thiago’s IP address should be banned for all the useless, counterproductive trolling he’s done.

Because you are lying to try to elect lying Warren.

Nice try. I didn’t even mention her name. My post had nothing to do with Warren.

Yes, it had. The corrupt Democratic Party machine wants to steal another nomination and nominate Warren. It won't happen. We are the people!

At this point, I'm willing to accept the theory that Tyler is Thiago.

Is there any good reason why Ty lets Thiago crap all over his website?

The only explanation for that would be a weird sexual fetish, or a long term GMU study on human-propaganda bot interaction.

More Sex is Safer Sex.

I have been telling this

To my wife for years.

That's correct but what's special about the names Stacy and Becky? They seem perfectly ordinary to me.

Thank god we have prostitutes. And wankers.

I never heard that before; thanks for clarifying. I thought Stacy and Becky were slightly old-fashioned names and that all young women were named Ashley if over 25 and Madison if under. Hence the website

This is what happens when nerds who know nothing about sex attempt to understand how it all works.

This is by far the most idiotic thing I’ve ever seen on this blog

I found the newbie!

Sorry -- just think of MR as the National Enquirer of blogs. Nothing has to make sense here. Laughably false things get posted all the time. It's all about what SEEMS INTERESTING.

Wait, wait wait... The CDC is promoting abstinence from sex? That's like trying to control obesity by promoting starvation. Sure, technically, there would be no obesity if people actually stopped eating food, but the end result would be the opposite of good health.

Just where does a government organisation get off (or fail to get off) promoting unhealthy behavior among that is likely to shorten lives and add to the burden of ill health in society? It sounds like they have been co-opted by religious nuts.

The spread of AIDS depends far more on the level of male homosexual promiscuity than on the level of heterosexual promiscuity, since buggery is inherently unsafe, as Michael Fumento explained in his 1990 book "The Myth of Heterosexual AIDS".

When he's old enough, someone should take him aside and explain that heterosexuals can do butt stuff.

That was likely unfair snark given that publishers often choose the titles of books, not authors.

Alex, next time you are fawning over Larry Summers ask him about his opinion on Epstein and pedophilia. I bet they had some interesting conversations

The model is ludicrous.

1. Less sex is clearly safer for Martin, who isn't going to get an STD by staying home.

2. Less sex would have been safer for Joan,

3. On what basis does Landsburg assume that Maxwell wouldn't have connected with some other woman had Martin and Joan gotten together?

There seems to be a sort of "lump of sex" fallacy here - an assumption that there will be a fixed number of sexual encounters, so that if prudent people participate in more of them, imprudent people will participate in fewer.

The whole thing is pathetic in way that Landsburg specializes in.

Well, yeah... The spirit is willing, but the sex is lumpy.

I am Martin. If I save Joan this time, do I have to save her from Maxwell at the next office party too? What about the time after that? I might decrease her risk this time, but have I not helped encourage her in a habit which puts her at greater cumulative risk across her life-time? What about my own risk of contracting from Joan? (Mightn't she have already hooked up with Maxwell?) Does increasing my own risk not mean anything?

I married Joan instead, before she went down the path of promiscuity. By thus doing, I removed both of us from the pool of people at risk of contracting STDs. In my view, this makes the system and population as a whole better off. Of course, it does not help those who are still in the pool of at-risk persons ("the rest of us"). I don't care. They can go to hell.

Is this theory consistent with other communicable diseases? Are you less likely to get the flue working in a large office in a city than in a small office in a small town? Does travel reduce the spread of the flu?

Is data on herpes infections over time consistent with this theory?

Good day Sir/Madam,

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