I do not believe that anything really worthwhile will come out of the exploration of the slag heap that constitutes the surface of the moon...Nobody … - Fred Hoyle

It has often been said that, if the human species fails to make a go of it here on the Earth, some other species will take over the running. In the sense of developing intelligence this is not correct. We have or soon will have, exhausted the necessary physical prerequisites so far as this planet is concerned. With coal gone, oil gone, high-grade metallic ores gone, no species however competent can make the long climb from primitive conditions to high-level technology. This is a one-shot affair. If we fail, this planetary system fails so far as intelligence is concerned.

It is easy to give a recipe for writing a successful non-fiction book—simply find grounds for optimism that no one has spotted before and expatiate thereon.

The concept here is that a highly organized society can collapse through a population overload, even though the people themselves are not starving. It is the organization that ultimately becomes overloaded and collapses.