Book Review: More Sex Is Safer Sex

Steven Landsburg’s contribution to the recent flood of pop economics books, More Sex Is Safer Sex, focuses attention on the concept of spillovers and endorses a strong application of cost-benefit analysis. Like other recent books in the genre (Stephen Levitt’s Freakonomics, Ian Ayres’ Supercrunchers, or Robert Frank’s The Economic Naturalist) it is quick reading, and while the reader may or may not agree with all Landsburg offers, he must surely agree that it is thought-provoking and entertaining. Drawing on material from his years as a columnist for Slate, Landsburg delivers a collection of antecdotes with poignant economic insights. This material would be very useful to anyone seeking to enliven an introductory economics class or a cocktail party.

The book begins with the titular chapter, claiming that if the pool of prospective sexual partners is larger, then all participants are less likely to contract an STD. Recreational sex is welfare-enhancing, and aside from the spillover of infection, Landsburg hypothesizes that more people would participate in it. In order to lure otherwise bashful prospective partners from the sidelines and increase the size of the pool, Landsburg suggests that used condoms should be exchangeable for a reward (this is because even at zero cost, a less than socially optimal number of condoms would be used). Thus more people have sex, reducing the chances of infection. But wait, doesn't condom use reduce the risk of infection? Presumably wider-spread condom use would also mitigate the risk of infection just as surely as lerger numbers of uninfected partners. It's also not clear to me that sexual pairings are random. In any event, sexual relationships are evidently a scale-free network, so it's not clear that adding a whole lot of nodes is the way to attack the problem of infection. It seems that attacking the hubs is the way to do it. Landsburg has clearly achieved his goal, since I had to understand his argument in order to come up with that.

Landsburg continues to sling economics curveballs throughout the book. A few examples give the spirit.

• Underpopulation (not overpopulation) is the world's most pressing problem since people solve problems. With more of them, more problems will be solved. (Steve, did you know that only stupid people are breeding?)
• Juries should be paid for correct verdicts and fined for incorrect ones. SURPRISE! The legal system doesn't get the incentives right.
• As a miser, Scrooge was actually among the most generous of people by producing valuable goods and services but not consuming any--at least, until the end of The Christmas Carol. (This smells like pecuniary externalties to me.)
• People (except tycoons with potnetially endowment-changing contributions) should donate to a single charity rather than to multiple charities. Corrollary: Maimonides' Rule is a crock.
• Patents should be purchased by the government and held in the public domain. This rewards innovation and allows public use of knowledge.

All in all, it's a worthy collection of thoughts, logic, contrarianism, and jokes. Landsburg deserves a lot of credit for owning up to the internal conflicts between his fee market training (Chicago) and proclivity and his enthusiasm for selected government interventions (like the condom bounty) in economic life. One sidenote that comes up three or four times during the book: Landsburg has a hardon for Robert Frank of Cornell. Apparently the claim to be the top dog in pop economics is valuable. A cage match sounds like a good idea.