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How many people have ever lived on Earth?

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Re: How many people have ever lived on Earth?

#31

> Average life expectancy in Iron Age France (from 800 B.C.E. to about 100 C.E.) has been estimated at only 10 or 12 years. Doesn't that sound extremely weird? Like, how does puberty, and 9 months to have a baby, fit in with a 12 year total life expectancy? Maybe I need more coffee or something...

[deleted]

Re: How many people have ever lived on Earth?

#32

> Average life expectancy in Iron Age France (from 800 B.C.E. to about 100 C.E.) has been estimated at only 10 or 12 years. Doesn't that sound extremely weird? Like, how does puberty, and 9 months to have a baby, fit in with a 12 year total life expectancy? Maybe I need more coffee or something...

[deleted]

Re: How many people have ever lived on Earth?

#35
post #22

Wondering how many will ever be born here, if it lasts until the sun dries out for example

The Doomsday Argument[0] relates to this. It says that since the reader is born in the current times with there being X billion humans so far, statisticslly there shouldn't be too many more (not say tens of trillions). I don't think the logic is too sound though. Or rather that the premises should be taken for granted. [0] https://en.wikipedia.org/wiki/Doomsday_argument

I take solace in the Rebuttals section being longer than the actual argument.

Re: How many people have ever lived on Earth?

#37

Wondering how many will ever be born here, if it lasts until the sun dries out for example

I believe current estimate is that the Earth becomes uninhabitable in 1 billion years (increased luminosity will remove all liquid water), well before the sun completes its lifecycle.

Re: How many people have ever lived on Earth?

#39

> Average life expectancy in Iron Age France (from 800 B.C.E. to about 100 C.E.) has been estimated at only 10 or 12 years. Doesn't that sound extremely weird? Like, how does puberty, and 9 months to have a baby, fit in with a 12 year total life expectancy? Maybe I need more coffee or something...

That average, there are people life longer than that.

[deleted]

Re: How many people have ever lived on Earth?

#40
post #30

> Average life expectancy in Iron Age France (from 800 B.C.E. to about 100 C.E.) has been estimated at only 10 or 12 years. Doesn't that sound extremely weird? Like, how does puberty, and 9 months to have a baby, fit in with a 12 year total life expectancy? Maybe I need more coffee or something...

I think this is a case where an average value cloaks the distribution. Consider very high infant and childhood mortality rates, and how that might skew the average value.

Thanks all, that definitely makes sense. :)
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