"One might think Humanity’s success is guaranteed, except for a few things: First, the increasing scarcity of oil, coal, and natural gas suddenly threatens to remove the punch bowl from which Humanity has been feeding. Second, the carrying capacity of the Earth is far less than 8 billion humans unless we continue to supplement with increasingly scarce resources. And, last, our centuries-long party has now broken the Earth in ways Humanity cannot repair."
January 1, 1970
https://en.wikiquote.org/wiki/Overpopulation