The environmentalists are correct: Population growth that causes people to level forests and overgraze lands exacerbates poverty.
The socialists are correct: The helplessness of poverty creates the motivation for parents to have many children, as their only hope of providing for themselves.
The free-marketers are right: Economic development can bring down birthrates.
The optimists are right: Development schemes work, but not when they are imposed by large bureaucratic institutions such as the World Bank.
Capital can be the scarcest factor of production at some times and places, labor at other times and places, materials and energy and pollution-absorption capacity at still others. The limits the environmentalists point out really are there. So are the injustices that anger the socialists. So are the market and technical responses the free-marketers have faith in. And so is the wisdom of the people that the optimists respect.
From Natural Capitalism