A population of zero is also sustainable.

Dream on!

As I would have expected, the reaction to Jack Alpert’s video is strongly negative. Of course a population of 100 million is a repulsive notion, once we start to think of how it might be achieved.

Alright, so here’s another view that says that the global population is three times over the sustainable level.

http://www.worldpopulationbalance.org/3_times_sustainable

How realistic do you think this is?

Alpert makes sense to me. Our population growth will be reversed eventually. It can be reversed by conflict, starvation, disease or other nasty means. It can be reversed by humans realising that the present level is not sustainable and adopting the most humane methods possible to decrease the population. We will probably choose the former. Alpert's video is an attempt to raise consciousness so we choose the latter.

Whatever we choose our population will eventually be reduced. Eventually like other species we will be extinct. However, we can delay our extinction by using humane means to reverse our population growth.

No species can increase in numbers indefinitely.

You're still not going to convince anybody much with those figures, Ludwig. Is the planet's sustainable population 100 million or 2 billion? Given the huge discrepancy between the estimates, which is correct?

david f, I agree that the current world and Australian populations are unsustainable at our present levels of material consumption. However, I think that plucking widely disparate figures out of the air is not a good strategy for convincing the 'growthists' that they're wrong.

Alpert's figure of 100 million seems ridiculously low, particularly since there is no indication of how such a small world population might be humanely achieved.

Ludwig and others
You are on a hiding to nothing on this one.

Anyone not intellectually wedded to the Norman Lindsay's school of 'culinary reality', knows that humans are consuming themselves self out of food and home, in one bloody big orgy of excess.

notwithstanding, both are based on assumptions that resemble a colander.

Rather than pick it to pieces let me suggest that they would learn a lot from the song title "from little things, big things grow". (small steps, perhaps)

The idea needs thinking through on issues we're addressed before namely *HOW*. One needs to also pay closer attention to human nature.
Fear.... who are going to be the lucky few left? how will it be determined and of course the 'country attitude' "Change? it's us versus them again".

The Uber capitalist (we know a few or them)'I'm entitled!' or more recognizably "Damn socialism by stealth!"
The consumerist cattle "where's the fun, the innovation (toys)?".
The list goes on.

What is needed is to change attitudes from the 'more' to 'enough is as good as a feast'.

The key point is that shock tactics or shear logic doesn't work with the greater public, without whom the idea is dead in the water.

One only needs to look at the AGW debate(?) and the down right deviousness tactics of vested interests there-in. While I'm not a grand fan, as an ex-marketeer I tend to look for the smudged finger prints of manipulation and tactical advantage.

How they play on the emotional 'orphans' i.e. an author of 'conflicted' interests and their part in the country tour of 'Brother Love's traveling salvation show'. I hope you get my drift

No wonder mental health issues are on the rise when this sort of human hating garbage is not only promoted but believed by the gullible. Surely the gigantic uncovering of scientist fraudsters should wake up enough people to the false crap that social engineers want to impose on people.