From a Wash Times review of economist (and occasional Reason contributor) Steven Landsburg's new book, More Sex is Safer Sex:
The "More Sex" thesis: If prudes occasionally slept with strangers, it would slow the spread of STDs.
Here's how it works. One such prude walks into a bar, and he's uninfected. If he takes home an uninfected woman, great—he distracted her from a potential disease carrier. If he gets herpes, that's also great, because he's sexually conservative and won't pass the infection along very often. Better him than someone with less self control.
Either way, society benefits when the chaste open up slightly.
The reviewer concludes, the "book reads fast and provides plenty of intellectual red meat." Whole thing here.