7 replies to this topic

[bascule]

I was looking at a chart of the projected growth of Earth's population yesterday:

http://www.prb.org/C...tion_Growth.htm



As you can see, it shows us in the middle of an exponential trend. But the full shape of the graph is more akin to an S-curve, tapering off as time goes by.

I then remembered the graph Kurzweil had done of exponentially increasing human life expectancy in his Law of Accelerating Returns article:



And thought what a gross oversight it was in the population growth study.

Surely the exponential growth of the human population will continue on its present trend due to exponentially increasing lifespans, will it not?

People don't seem to grasp this... (well, perhaps the people in this forum do, society as a whole is oblivious)

[Mind]

Remember....population growth also depends on the birth rate. In fact it is much more highly dependent on the birth rate.

Just think of it this way. If no one died and no one was born, how much would the population change over the next 30 years? There would be no change. Birth rates in developed countries are waaaaaaaay down over the last couple decades and the birth rate in less developed countries is also going down - even without birth control laws.

[Live Forever]

Overpopulation is not a problem. Kurzweil, Aubrey de Grey, as well as others have shown that just using today's technologies that life extension will not put a serious burden on the planet without even mentioning technologies that are out of the realm of public consciousness (ex. uploading).

[bascule]

Remember....population growth also depends on the birth rate. In fact it is much more highly dependent on the birth rate.

Just think of it this way. If no one died and no one was born, how much would the population change over the next 30 years? There would be no change. Birth rates in developed countries are waaaaaaaay down over the last couple decades and the birth rate in less developed countries is also going down  - even without birth control laws.

But if you have a stable (nonzero) birth rate and eliminate aging/natural death, the population will continue to increase exponentially. When people are living 500+ years, what's to stop them from having, say, 8 families and raising 8 sets of children?

Overpopulation is not a problem. Kurzweil]Aubrey de Grey[/URL], as well as others have shown that just using today's technologies that life extension will not put a serious burden on the planet without even mentioning technologies that are out of the realm of public consciousness (ex. uploading)

I'm certainly not saying it's a problem at all, but I think earth's population is growing exponentially and, aided by exponentially increasing lifespans, will continue to do so until the advent of posthumanity.

[bgwowk]

bascule said

But if you have a stable (nonzero) birth rate and eliminate aging/natural death, the population will continue to increase exponentially.

No. If, for example, every couple makes a fixed number of children and then stops, long-term population growth will be linear, not exponential.

When people are living 500+ years, what's to stop them from having, say, 8 families and raising 8 sets of children?

When people are living to be 80 years old in wealthy countries, what's to stop them from having ten kids like short-lived people in poor countries? Answer: They have the knowledge and resources to choose otherwise, and most do choose otherwise.

Why assume that just because something is possible, everbody will do it? Asking why immortality wouldn't result in exponential population growth and Malthusian disaster is like considering modern automobiles and asking, "What's to stop everybody from just turning the steering wheel and crashing into everybody else?" Answer: Because people choose not to.

Debates about exponential growth are ultimately academic because the universe by its nature will not permit it. The universe cannot sustain long-term population growth at a rate higher than time cubed, so that is probably what the growth rate of immortals (humans or posthumans) will end up being. Either entities choose to live within their means, or reality forces them to. That's equally true for mortals, immortals, posthumans, pre-humans, whatever. Immortality has *nothing* to do with it. Nothing at all.

---BrianW

[John Schloendorn]

graph Kurzweil had done of exponentially increasing human life expectancy

Heh, I can see nothing exponential in this graph, at least not in the dots underlying it... It is a miracle he cannot get it to look more like exponential by picking the time points as arbitrarily as he does!

As I have just argued elsewhere, the past trend of increasing life expectancy at birth *must* hit a ceiling as soon as nearly everyone who is born lives to see 50 years, because life-expectancy at fifty has nearly not been increasing at all in the past century.

Overpopulation is not a problem. Kurzweil, Aubrey de Grey, as well as others have shown

Nobody has "shown" anything. They have made an argument and expressed their opinion, that's all.

And well, said Brian!

[jaydfox]

because life-expectancy at fifty has nearly not been increasing at all in the past century.

Actually, it's been increasing at a little more than 0.1 years per year, starting in the 1960's or so, which is about a third to half as fast as the rate of increase for LE from birth during that period.

Edit: added s's; my 's' key isn't working too well.

[rillastate]

I may be a moron here, but both of those graphs seem awfully linear to me. Where's the exponentiallity...(wow, that word reminds me of that merry poppins song for some reason)