[1] Many articles about global population just assume that overpopulation is a problem, and that the more people a poor country has, the likelier it is to remain poor. But Eberstadt of the American Enterprise Institute argues that these "obvious" facts often prove "to be either impossible to substantiate or demonstrably false." 

[2] What, for instance, does it mean to say a country is "overpopulated"? If overpopulation is measured by population density, then Bermuda must be overpopulated, because it has more people per square mile than Bangladesh. If overpopulation is measured by the rate at which a country's population rises, then the U.S. in the last half of the eighteenth century was overpopulated, since America's population shortly after independence rose at a faster annual rate than the population of Africa has risen in the past quarter-century. 

[3] Most of the problems associated with "overpopulation"-starving children, packed cities, disease-are actually problems of poverty, not of population. And on the poverty front, progress is being made. Between 1900 and 1992, the world's population has tripled, but economic historian Angus Maddison calculates that the global gross national product has quadrupled. Parts of the Third World have done quite well. Maddison calculates that Brazil's economy has increased by 600 percent during this period, while the Mexican and Turkish economies have quadrupled. Even the poorest countries are doing better than before. The average African nation is twice as rich today as it was in 1900. 

[4] Eberstadt also warns against accepting demographic forecasts uncritically. Demographers, he argues, are very good at calculating life spans of people who have already been born, but "cannot provide us guidance when it comes to the unbornand to long-range population trends." A comparison of 1977 United Nations estimates of 1990's population levels to actual data, for instance, shows that most of the U.N. forecasts were substantially wrong. The demographers predicted that average Mexican women in the '90s would have at least five children; the actual rate is about three. Brazilian families, according to the U.N., would have four children on average in the 1990s; the actual rate is about two. Overall, Eberstadt calculates, the U.N. demographers predicted global families would have nearly one child more than they have actually had. 

[5] Eberstadt concludes that we should be wary of sweeping analyses of global population trends. "When it comes to population matters," he warns, "reach is often greater than grasp."