Re: Need Clarification on MW

From: Fred Chen <flipsu5.domain.name.hidden>
Date: Tue, 07 Dec 1999 23:25:12 -0800

Fritz Griffith wrote:

>First of all, there is a theorem which states that choosing a random
>number out of a set of n numbers, labelled 1 to n, will give a general idea
>of the size of the set. For example, if the randomly chosen number is 7,
>you can deduce that there is a high probability that the set does not
>consist of very many numbers. But if you choose 1 billion, you know the set
>is very large. This principle, I assume, (and read about, called the
>Doomsday Principle), applies to us. Assuming you are an SAS, randomly
>assigned to a single concioucness within this universe, then you must either
>assume:
>1. The set of past SAS's is infinite, and therefore there must have been
>SAS's before the big bang.
>or,
>2. The set of future SAS's is finite.
>If you do not assume either of these, then you must assume that the set of
>past SAS's is finite, and the set of future SAS's is infinite. But the
>chance of being randomly assigned to an SAS that does not live in a time
>that has an infinite future and past set of SAS's is infinitely small, and
>can therefore be discarded.
>So either life has been going on forever and will always go on, or it
>started at a certain point and will end at a certain point (which goes
>against MWI).
>Is this a proof that life has always existed?

John Leslie wrote a book entitled "The End of the World" in which he did
give
one special situation on p. 230 (akin to the AUH-SSA solution Hal wrote
about
earlier) which would offer hope of avoiding the Doomsday Scenario. This
is the
case where a short-lasting species of (human) observers about to go
extinct
coexists with a long-lasting species in our universe. Like the AUH
solution, the
probabilities are balanced between finding yourself in a 'normal' place
in the
history of the short-lasting species and finding yourself early in the
long-lasting species. This could be generalized to many species of
intelligent
SAS observers in our universe. Of course, this makes the leaping
assumption that
we are not the only intelligent SAS observers in the universe.

Fred
Received on Tue Dec 07 1999 - 23:29:49 PST