Fewer people, please

Robert Engelman is concerned about overpopulation:

Arguably, population is the greater force than per capita consumption in these interactions. There are roughly a thousand times more people on the planet today than at the dawn of agriculture. But even with all our use of fossil fuels and other natural resources, it seems unlikely that the average human being today has a thousand times the environmental impact of individual hunters and gatherers, who depended on large animals and wild plants for their food supply. In any event, it is obvious that no amount of reduction in individual consumption can produce enduring sustainability if population does not stop growing. If we ever succeed in eliminating the gross disparities that today characterize per-capita consumption levels, our success will make even more obvious the eventual necessity of a non-growing population for true sustainability.