The day may come when the obese people of the world must give up diets, since metabolizing their fat deposits will lead to DDT poisoning. But, on the… - Paul R. Ehrlich

The idea that we can just keep growing forever on a finite planet is totally imbecilic.... Julian Simon, a professor of junkmail marketing, and his kind, think technology will solve everything.... We can use up the Earth then we can just jump into spaceships and fly somewhere else.... Technology does nothing to solve problems of biodiversity or living space or arable cropland.... Fresh water and arable cropland are finite resources.... We are already far beyond what we can support sustainably.... The provincial view you get from someone living in some wealthy American East Coast city is wildly different from reality. Most of the world is tropical, hungry and poor. Visit the developing world and southern hemisphere and you get a very different view of reality.

The key to understanding overpopulation is not population density but the numbers of people in an area relative to its resources and the capacity of the environment to sustain human activities; that is, to the area’s carrying capacity. When is an area overpopulated? When its population can’t be maintained without rapidly depleting nonrenewable resources.... By this standard, the entire planet and virtually every nation is already vastly overpopulated.

Interstellar transport for surplus people presents an musing perspective. Since the ships would take generations to reach most stars, the only people who could be transported would be those willing to exercise strict birth control. Population explosions on space ships would be disastrous. Thus we would have to export our responsible people, leaving the irresponsible at home on Earth to breed.