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What percentage of people are alive today?

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Re: What percentage of people are alive today?

#41

Post by spindritf »

yummyfajitas wrote: post #33
reasonattlm wrote: post #24

Earlier quoted context omitted.

Malthus was wrong in principle. He didn't understand human action or economics, and that misunderstanding remains very common. See: http://www.fightaging.org/archives/2006/09/overpopulation.ph... "Common Malthusianism - the idea that a given resource (such as living space or food) will run out in the future based upon extrapolation of present trends - stems from fundamental misunderstandings about economics, human ac…

"Common Malthusianism" is a strange name to apply to a claim Malthus didn't make. Malthus didn't attempt to extrapolate current trends, he merely pointed out (correctly) that there will eventually be a limit to productivity. From "An Essay on the Principles of Population": We may be quite sure that among plants, as well as among animals, there is a limit to improvement, though we do not exactly know where it is. It i…

> he merely pointed out (correctly) that there will eventually be a limit to productivity

I don't understand this point. Why would there be a limit to productivity, especially with machines and computers to leverage our efforts thousandfold and more?

And how could anyone know that such limit exists, even if it is actually reached one day? That would require predicting any possible innovation of the future.

Re: What percentage of people are alive today?

#42

Post by wulczer »

hugh3 wrote: post #40
wulczer wrote: post #38

Earlier quoted context omitted.

And he died condemned to death and executed, too! So he could have lived happily for many more years.

Xenophanes of Colophon supposedly lived to 95. Pyrrho of Ellis lived to 90, and Democritus to 109. On the other hand, Epimenedes is supposed to have lived to the age of 154 or 290 depending on whom you believe, so take these numbers with a grain of artery-clogging sodium chloride.

Yeah, and Noah reportedly died at 950, so I'd definitely take these numbers with a drop of hemlock :)

Re: What percentage of people are alive today?

#43

Post by corin_ »

hugh3 wrote: post #40
wulczer wrote: post #38

Earlier quoted context omitted.

And he died condemned to death and executed, too! So he could have lived happily for many more years.

Xenophanes of Colophon supposedly lived to 95. Pyrrho of Ellis lived to 90, and Democritus to 109. On the other hand, Epimenedes is supposed to have lived to the age of 154 or 290 depending on whom you believe, so take these numbers with a grain of artery-clogging sodium chloride.

Go back far enough in history and numbers get even less believable, just think of Methuselah.

Re: What percentage of people are alive today?

#44

Post by a-priori »

amalcon wrote: post #23
iskander wrote: post #20

Earlier quoted context omitted.

I'm still not completely getting it. Let's say in some year there are a billion people alive and the average life expectancy is 50 years. How are these two pieces of information sufficient to determine how many children were born in that year?

You also need the previous year's population. With population and life expectancy, you can approximate the per capita death rate, and then it's a straightforward linear equation.

What about infant mortality? If a million babies are born in the year 234BC, and die before 233BC rolls around, they won't be counted in the population for either year.

Re: What percentage of people are alive today?

#45

Post by barry-cotter »

spindritf wrote: post #41
yummyfajitas wrote: post #33

Earlier quoted context omitted.

"Common Malthusianism" is a strange name to apply to a claim Malthus didn't make. Malthus didn't attempt to extrapolate current trends, he merely pointed out (correctly) that there will eventually be a limit to productivity. From "An Essay on the Principles of Population": We may be quite sure that among plants, as well as among animals, there is a limit to improvement, though we do not exactly know where it is. It i…

> he merely pointed out (correctly) that there will eventually be a limit to productivity I don't understand this point. Why would there be a limit to productivity, especially with machines and computers to leverage our efforts thousandfold and more? And how could anyone know that such limit exists, even if it is actually reached one day? That would require predicting any possible innovation of the future.

I don't understand this point. Why would there be a limit to productivity, especially with machines and computers to leverage our efforts thousandfold and more?

There are limits to what you can do with matter. It's unlikely the economy (our productive capacity) will continue to grow much for 100,000 years after all mass we can get at is weird ass artificial quark composite computronium.

Re: What percentage of people are alive today?

#46

Post by TeMPOraL »

petercooper wrote: post #31

Not to detract from the insight but: Until very recently life expectancy at birth hovered between 20 and 35 years, but in the past century it has risen to 67 years Most of this increase has been due to a precipitous crash in infant mortality, rather than a soaring increase in the median life expectancy. For example, even in the 1500s it seems a well-to-do Englishman (who lived a somewhat more hazardous life medically…

I still don't understand why the average is used instead of median (or average of data between the first and third quartile), when people talk about life expectancy. It leads to misconceptions.

Re: What percentage of people are alive today?

#47

Post by [deleted] »

wulczer wrote: post #42
hugh3 wrote: post #40

Earlier quoted context omitted.

Xenophanes of Colophon supposedly lived to 95. Pyrrho of Ellis lived to 90, and Democritus to 109. On the other hand, Epimenedes is supposed to have lived to the age of 154 or 290 depending on whom you believe, so take these numbers with a grain of artery-clogging sodium chloride.

Yeah, and Noah reportedly died at 950, so I'd definitely take these numbers with a drop of hemlock :)

[deleted]

Re: What percentage of people are alive today?

#49

Post by b_emery »

ANH wrote: post #29
georgieporgie wrote: post #28

I thought that 'humans', as in, you would see one and say, "yeah, that weird looking guy over there," went back about 2.2 - 2.3 million years. http://en.wikipedia.org/wiki/Human_evolution Populations would have been small, but an extra 2.1 million years is a long time.

There have been catastrophic events in that time that some believe acted as population bottlenecks, in particular the Toba eruption 70,000 years ago: http://en.wikipedia.org/wiki/Lake_Toba Of course, there is much debate about the effect this had. [edit] In a recent Seminar About Long Term Thinking, a biologist said that there is evidence the human population was reduced to a few thousand by the Toba event. That is t…

Quote from that link:

"There is some evidence, based on mitochondrial DNA, that the human race may have passed through a genetic bottleneck around this time, reducing genetic diversity below what would be expected from the age of the species. According to the Toba catastrophe theory proposed by Stanley H. Ambrose of the University of Illinois at Urbana-Champaign in 1998, human populations may have been reduced to only a few tens of thousands of individuals by the Toba eruption."

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