Which is more dangerous, a gun or a swimming pool? What do schoolteachers and sumo wrestlers have in common? Why do drug dealers still live with their moms? How much do parents really matter? What kind of impact did Roe v. Wade have on violent crime?

These may not sound like typical questions for an economist to ask. But Steven D. Levitt is not a typical economist. He is a much heralded scholar who studies the stuff and riddles of everyday life-;from cheating and crime to sports and child rearing-;and whose conclusions regularly turn the conventional wisdom on its head. He usually begins with a mountain of data and a simple, unasked question. Some of these questions concern life-and-death issues; others have an admittedly freakish quality. Thus the new field of study contained in this book: freakonomics.

Through forceful storytelling and wry insight, Levitt and co-author Stephen J. Dubner show that economics is, at root, the study of incentives-;how people get what they want, or need, especially when other people want or need the same thing. In Freakonomics, they set out to explore the hidden side of ... well, everything. The inner workings of a crack gang. The truth about real-estate agents. The myths of campaign finance. The telltale marks of a cheating schoolteacher. The secrets of the Ku Klux Klan.

What unites all these stories is a belief that the modern world, despite a surfeit of obfuscation, complication, and downright deceit, is not impenetrable, is not unknowable, and-;if the right questions are asked-;is even more intriguing than we think. All it takes is a new way of looking. Steven Levitt, through devilishly clever and clear-eyed thinking, shows how to see through all the clutter.

Freakonomics establishes this unconventional premise: If morality represents how we would like the world to work, then economics represents how it actually does work. It is true that readers of this book will be armed with enough riddles and stories to last a thousand cocktail parties. But Freakonomics can provide more than that. It will literally redefine the way we view the modern world.

Economics is not widely considered to be one of the sexier sciences. The annual Nobel Prize winner in that field never receives as much publicity as his or her compatriots in peace, literature, or physics. But if such slights are based on the notion that economics is dull, or that economists are concerned only with finance itself, Steven D. Levitt will change some minds. In Freakonomics (written with Stephen J. Dubner), Levitt argues that many apparent mysteries of everyday life don't need to be so mysterious: they could be illuminated and made even more fascinating by asking the right questions and drawing connections. For example, Levitt traces the drop in violent crime rates to a drop in violent criminals and, digging further, to the Roe v. Wade decision that preempted the existence of some people who would be born to poverty and hardship. Elsewhere, by analyzing data gathered from inner-city Chicago drug-dealing gangs, Levitt outlines a corporate structure much like McDonald's, where the top bosses make great money while scores of underlings make something below minimum wage. And in a section that may alarm or relieve worried parents, Levitt argues that parenting methods don't really matter much and that a backyard swimming pool is much more dangerous than a gun. These enlightening chapters are separated by effusive passages from Dubner's 2003 profile of Levitt in The New York Times Magazine, which led to the book being written. In a book filled with bold logic, such back-patting veers Freakonomics, however briefly, away from what Levitt actually has to say. Although maybe there's a good economic reason for that too, and we're just not getting it yet. --John Moe