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Archiver > GEN-MEDIEVAL > 1999-07 > 0932322952


From: "D. Spencer Hines" <>
Subject: "Everyone of European Ancestry is Descended From Charlemagne"?
Date: Sun, 18 Jul 1999 08:35:52 -1000


_Everyone of European Ancestry is Descended From Charlemagne_

Readers will find this piece at:

http://www.oz.net/~lee/Genealogy/charlemagne.html

D. Spencer Hines

It was reportedly written by:

John M. (Jack) Lee
Professor of Mathematics
Graduate Program Coordinator
University of Washington
Department of Mathematics
C-546 Padelford Hall
Box 354350
Seattle, Washington 98195-4350
USA
Phone: (206) 543-1735
Fax: (206) 543-0397
E-mail:

Whose Home Page is at:

http://www.math.washington.edu/~lee/

D. Spencer Hines

Lux et Veritas
Fortem Posce Animum
--

As I was researching my Lee ancestral line back into the middle ages,
I was excited to find that I am apparently a direct descendant of
Charlemagne, the first Holy Roman Emperor. As I dug deeper, I found at
least three separate lines of descent from him to me, and I saw more
and more genealogical sites on the Web that claimed similar descent.
This started me thinking about how likely it is that I, or anyone for
that matter, might be descended from a particular person that far
back. As a mathematician (though not by any means a probabilist), I
figured I ought to be able to come up with at least a rough estimate
of the probability. My conclusion, which was surprising (to me at
least), is that there is virtually no chance that anyone of European
ancestry is not directly descended from Charlemagne.

Here's my reasoning. Charlemagne was approximately 40 generations back
from the present day. Each person has 2 parents, 2^ 2 = 4
grandparents, 2^ 3 = 8 great-grandparents, ... and 2^ 40, or
approximately 1,000,000,000,000 (one trillion), 40th-generation
ancestors, which means half a trillion male ancestors. Of course,
since the entire male population of Europe at the time of Charlemagne
was only about 15 million, these half trillion ancestors cannot all
have been different men -- obviously there has been a lot of
cross-breeding, and many of our ancestral lines cross and re-cross,
eventually ending up at the same person. Let's assume that each of my
40th-generation male ancestors is a randomly-chosen man from
eighth-century Europe (this is not really valid, but more on that
below). Choosing any one such ancestor, say my father's father's ...
father's father, the probability that that particular person is
Charlemagne is one in 15 million. Pretty small. To put it another way,
the probability that any particular ancestor was not Charlemagne is
1 - 1/15,000,000, or approximately 0.999999933

But now consider the probability that none of my 40th-generation
ancestors is Charlemagne. For that to happen, every one of my half
trillion male ancestors has to not be Charlemagne, which would be an
amazing coincidence. To see how amazing, let's compute the
probability. Assuming all of these various not-being-Charlemagne
occurrences are independent of each other (more on this below), the
laws of probability state that the probability of all these events
occurring simultaneously is obtained by multiplying together their
individual probabilities:

(0.999999933)(0.999999933)...(0.999999933) = (0.999999933)^
500,000,000,000.

This turns out to be an incredibly small number: about one chance in
10^ 15,000. That's a one with 15,000 zeroes after it, a number that's
too big even to display in a browser window. This is way more than the
number of atoms in the universe (which is estimated to be about 10^
80). Therefore, if this analysis is even remotely close to correct,
it's virtually impossible that Charlemagne is not among my direct
ancestors.

Of course, there are a few sources of errors in this analysis, so
there are various corrections one could make that might yield a more
accurate estimate. Most obviously, one's ancestors are not in fact
randomly chosen people from eighth-century Europe. For example, anyone
who had no children, or no grandchildren, cannot be an ancestor of
someone living now. (Charlemagne has well-documented descendants down
to the present day.) More generally, wealthy people survived at a far
higher rate than the rest of the population, and so were much more
likely to produce descendants - thus one's ancestors are more likely
to be found among the relatively small population of royalty and
nobility, including Charlemagne. You might think of other, smaller,
corrections, such as the fact that the probabilities of different
ancestors being Charlemagne are not really independent: for example,
if my father's ... father's father was Charlemagne's brother, then the
probability that my father's ... mother's father was Charlemagne
himself is very small. And, of course, some of my ancestors came from
outside of Europe. But I believe these effects cannot change the fact
that the probability we're talking about is so tiny as to be zero for
all practical purposes.
- --------------------------------------------------------------------
----------
Lee/Weizenbaum Genealogy Lee/Weizenbaum Home

http://www.oz.net/~lee/Genealogy/charlemagne.html
--

D. Spencer Hines --- "She [Hillary Rodham Clinton] loves eunuch geek
men." [CP]; "Like Who?" [The Women's Quarterly]; "Oh my God, look at
them all! Sidney Blumenthal, Ira Magaziner, Harold Ickes --- they all
look alike. They are all weird Ichabod Crane men, all high IQ men who
have no natural virility, okay? It's really weird. She loves to have
her little cabals with them. And the other one --- the lawyer David
Kendall --- they're all alike, and they all bond with her. They're all
joined at the hip with her! "Camille Paglia, Professor of Humanities
at the University of the Arts in Philadelphia is a culture critic,
libertarian feminist, and columnist for the Internet magazine _Salon_.
She is also the author of four books including _Sexual Personae: Art
and Decadence from Nefertiti to Emily Dickinson_; _Art and American
Culture_; and _Vamps and Tramps_." _The Women's Quarterly_, Spring
1999, Number 19.

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