Came up in Q&A. Hard to cover it all!

Overpopulation x consumption = Exponential depletion of resources + exponential increase of inorganic harmful waste

Thats about all you can say. Nobody can really do anything to control population (genocidal maniacs may disagree) but we can all do something about consumption of natural resources. Reducing consumption to a point which allows the currently overpopulated earth to depopulate through natural attrition is the only morally acceptable path we have.

Except that consumption of resources is strongly corrolated to benign demographic transition...

I have never seen evidence of a "benign demographic transition." Every nation that has apparently gone through it has an ecological footprint and accumulated debt that is enormous.

The best response to cornucopianism I've seen so far. +100

Do you really think Nature cares one iota whether human population can be reduced on a moral path? When the food supply can no longer be relied upon to support our vast numbers, billions will die in relatively short order of starvation, plus some disease. This is basic ecology, with many examples in the field and in the literature to cite. Some interesting modern examples for humans can be found in Northern China. Just scale up the process. It's not that hard to envision. Morality has nothing to do with it.