"I do believe ... that human population pressure--the sheer number of people on this planet--is the single most important cause of the degradation of the natural environment, of the progressive extinction of wild species of plants and animals, and of the destabilization of the world's climatic and atmospheric systems. The simple fact is that the human population of the world is consuming natural renewable resources faster than it can regenerate, and the process of exploitation is causing even further damage. If this is already happening with a population of 4 billion, I ask you to imagine what things will be like when the population reaches six and then 10 billion.... All this has been made possible by the industrial revolution and the scientific explosion and it is spread around the world by the new economic religion of development."