If people are a burden, sucking life out of the planet then yes, it’s possible to have too many. But if they are a promise for the future, then we need more.
The Demographic Bomb discusses these points. I wrote about that new documentary here.
(While I’m at it, I’ll recommend Fatal Misconception by Matthew Connelly. A good read, which looks at the history of population control across the globe.)
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This is really going to be a problem.
Too many people brings trouble. Serious trouble. Shortages of everything, massive environmental destruction, and eventually inevitable famine.
And yet we have set up economic systems that can function only so long as population is always increasing. If it ever stops growing, then we are still screwed, just in a different way – pension scheme collapse, and severe inequality.
And so far only one country has managed to get population control to work well, China, and that only by the use of some quite draconian policies that would never be permitted in any country with some protection for human rights.
I think the only long-term way to achieve a comfortable stability will be to go through whatever demographic disaster awaits, be it too many people or too low a growth rate.
Oh, and from what numbers I’ve been able to figure out… the two nightmare scenarios are both likely to occur, just in different places. Currently less-developed countries are either in the middle of an explosion or poised for one, and the most developed countries have already undergone theirs and are now into the decline stage. So I expect to see billions of people fleeing Africa, Asia, the Middle East and South America and making their way towards the promising comparative wealth of Europe and North America, who will have no choice but to accept all the immigrants they can get in order to pay the taxes to support their own ageing populations.