Ideally, how many humans should live per sq mile?

Question

I remember reading something that suggested that to live in an environmentally friendly way, there should only be about 1-2 billion humans on earth and not the huge amount we have now.

Can someone reduce this to sq miles? Is there any study that shows how many humans can live per sq mile, as to be sustainable and not exhaust and pollute their environments?

Answer 1

To me, it's not the number of humans, it is the total resource consumption by humans which governs the upper limits of population density.

Answer 2

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