Quirky way to beat queues

Take the state of Texas, divide it into lots of 5,000 square feet, put a house on each lot, and put a family of four in each house. You've just housed the entire world population."

Like one of those little believe-it-or-not books, More Sex Is Safer Sex is full of mind-boggling facts of this kind. But unlike the believe-it-or-not books, More Sex uses the mind-boggling facts to build equally mind-boggling hypotheses. The fact that Texas could easily house the world's entire population, leaving the rest of the globe deserted, is part of Steven Landsburg's justification for arguing that we should all start breeding like rabbits. Why? Because all creativity is a product of the human mind; thus the more human minds there are at large, the more likely it is that we will solve the world's problems (and overpopulation, in his view, is not one of them).

As the book's title suggests, Landsburg delights in being a quirky iconoclast - and More Sex Is Safer Sex is, in large part, a delightfully quirky, iconoclastic collection of essays. Landsburg's eccentric theses include the virtue of meanness ("What I like about Scrooge"); the virtues of sweatshops in underdeveloped countries; making jurors pay penalties if it turns out they got the verdict wrong, and rewarding them if their verdict is later substantiated; letting firefighters keep all the property they rescue, including the houses; and doing away with queues by getting people to join them at the front rather than at the back - which would swiftly ensure nobody would bother to line up behind them. If most of this sounds wacky, it is. But Landsburg advances his arguments with enthusiasm and painstaking logic, exploring the objections and dealing with them rigorously. This is not to say his arguments and logic are watertight. Most of them manifestly are not. But, in the main, they are sufficiently provocative and sufficiently well argued to force you to give them serious consideration before you reject them.

Unfortunately, one of Landsburg's weakest theses is the one encapsulated in the book's title. His attempt to prove that more sex is safer sex is based on the unarguable fact that people who have little sex and few partners are unlikely to catch, or to pass on, transmittable diseases. So the more sex these people have, the fewer the diseases that will be transmitted. True - unless they become so sexually active they become transmitters themselves. Worse, the presumption that the injunction to have "more sex" would somehow impinge only on the sexually inactive, bypassing those who are already sexually hyperactive, is palpable nonsense. To use marketing terminology, light users - of anything - are always less likely to increase their usage than heavy users are. This is because the light users do not enjoy whatever it is as much as the heavy users do. (That is why they are light users.) Landsburg has simply gone for a provocative, catchpenny title - a temptation economics professors should eschew.

Most of Landsburg's theses are intriguing, but by the end his almost desperate desire to be iconoclastic gets a mite wearisome. This is especially true of the book's final section, titled "The big questions". Here he analyses - in typically unconventional style - how to tell right from wrong, truth from fiction and other grand philosophical conundrums. But his understanding of human behaviours in these complex areas is heavy-handed. He retreats too often into the hardline economists' belief that every action human beings take they want to take. If people do not want to do something, he argues, they do not do it. But life is not that simple. We all do things we wish we did not - driven perhaps by our subconscious or by uncontrollable desires. Perhaps Landsburg is never driven by uncontrollable desires, except by his uncontrollable desire to be outrageous.

Similarly he attacks the naming of people he believes should simply be treated as statistics. He argues "the distinction between a statistical and an identified life is incoherent, morally obtuse and impossible to maintain... Why on earth should I care more about one stranger than another just because I happen to know their names?" Like most of Landsberg's arguments this seems rational at first blush: why should knowing the name of, say, a stranger killed in a car accident make any difference? But it does. The name gives the stranger in the car accident a humanity that being just a statistic denies him. This is precisely the kind of insensitivity that leads psychologists to question economists' blunter theories.

Still, even if many of his theses are dotty, Landsburg advances them with such exuberance that they are almost always fun to read, which is more than can be said for most economists' tomes.

Winston Fletcher is chairman, the Royal Institution.