Re: Thirty ghosts...
Brian Campbell
http://www.snopes.com/science/stats/dead.asp
According to this, using the most widely accepted figure of 60 billion as
the total population over time, at 6.6 billion now, that means there is 1
alive now for 9 dead, not to far off of my estimate 1:6 or 1:7 below.
When 2001 was written, I think the population was around 3 billion +,
meaning that the ratio then was 1:15 to 1:20 using this accepted figure.
But the article notes that estimates vary widely (up to 120 billion). So if
you assume a value halfway between the accepted value and the high end value
(i.e. 90 bilion dead), then Clarke's ratio 1:30 fits that value when when
2001 was written.
"Brian Campbell" <briandc...@qwest.net> wrote in message news:...
> OK, this quote has intrigued me as well. I do not know where Clarke got
> the number, but after looking into it a bit, I believe the number is
> rather high.
>
> First, Wikipedia (World Population article) claims that of the population
> living in the last 6,000 years, 1/5 is living today. That suggests a ratio
> of 1 person to 4 ghosts, since 4,000 BC.
>
> However, using a spreadsheet, I crunched their historical figures, making
> what I think were reasonable mortality rates, I came up with a ratio of 1
> to 5. Still within their ballpark. Projecting the population back to
> earlier historic times doesn't change this much.
>
> Going back to all prehistoric times, say when modern man emerged some
> 100,000+ years ago probably moves this up no more than a notch, probably 1
> to 6, or 1 to 7.
>
> Looking at the numbers in my spreadsheet, during the mid-60s when Clarke
> wrote the book, the ratio then looks more like 1 to 10.
>
>
>
> "Colonus" <sm...@iserv.net> wrote in message
> news:1154142568.5...@i42g2000cwa.googlegroups.com...
>> At the start of 2001 comes the asssertion that for every person now
>> living there are thirty ghosts.
>>
>> I've always wondered where that claim comes from. Is Clark quoting
>> some demography available at the time?
>>
>> Also, given population change since the book came out, what would the
>> ratio be now?
>>
>> thanks
>>
>
>