I suggest that the total number of dead people exceeds, by some
margin, the total number of people alive today (6 billion, I believe).
Is there some mathematical model for arriving at a reasonably accurate
figure?
Regards,,
Jack Wales

Dear jackwales-ga,

Any calculation of how many people have lived before is very
speculative as there are no reliable population figures prior to the
19th century, and do you mean homo sapiens or hominids?

The Population Reference Bureau has made some estimates and come to these figures,
Number who have ever been born 106,456,367,669 
World population in mid-2002 6,215,000,000

More information as to how that was reached is on this page.
http://www.prb.org/Template.cfm?Section=PRB&template=/ContentManagement/ContentDisplay.cfm&ContentID=7421


The US Census Bureau has a page on Historical Estimates of World Population
http://www.census.gov/ipc/www/worldhis.html

The contents of this page was discussed in a question was previously
asked on here on GA and you may be interested in the answer and
comments section.
http://answers.google.com/answers/threadview?id=609946

This United Nations Report - World Population Growth - may also be of interest.
http://www.un.org/esa/population/publications/sixbillion/sixbilpart1.pdf

In the absence of any reliable population figures, I believe that
these links best answer your question.

I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.
Thank you
answerfinder

A much fuller answer than I was expecting. You have contributed to an
on-going debate (initiated by me) at work. This is the first time I've
used GA. Many thanks.
Jack Wales

In the introduction to "2001" Arthur Clark wrote, ""Behind every man
now alive stand thirty ghosts, for that is the ratio by which the dead
outnumber the living."

What the Bible says; (Revelation 20:12-13) And I saw the dead, the
great and the small, standing before the throne, and scrolls were
opened. But another scroll was opened; it is the scroll of life. And
the dead were judged out of those things written in the scrolls
according to their deeds. 13 And the sea gave up those dead in it, and
death and Ha?des gave up those dead in them, and they were judged
individually according to their deeds.

Thought. The sea gave up its dead. Hades gave up its dead. This
implies that Hades is man's graves in the land. Not a place of
torment, as taught by some religions. And what about the 'very bad
individual' who happened to die at sea. Was he sent to Hades as a
ceaseless punishment? How can it be ceaseless if its going to be done
away with?
(Revelation 20:14) And death and Ha?des were hurled into the lake of
fire. This means the second death, the lake of fire.