archive: Re: SETI [Fwd: Probability of other ET Life is 1]

Re: SETI [Fwd: Probability of other ET Life is 1]

Dr. H. Paul Shuch ( (no email) )
Fri, 18 Dec 1998 08:59:17 -0500

At 05:22 AM 12/18/98 -0800, Alfred A. Aburto Jr. wrote:

>In the book Aczel writes that the probability (P) that there
>is life around at least one other star in the Galaxy

>First of all, we know that P0 is not zero, because life
>already exists on Earth.

>So, if this
>value of P0 is accurate, then, yes (!), there must be other
>life in the Universe! This is a pretty profound conclusion!

Maybe I'm missing something here. We determine that P0, the probability of
life forming, is not zero because we exist, and then we use that fact to
say that P, the probability that life has formed, equals 1. It's been a
long time since I took probability theory (as opposed to just plain
statistics), but to say that live exists in the Universe because life
exists in the Universe looks to me like circular reasoning.

Still, I gotta read that book.

H. Paul Shuch, Ph.D. Executive Director, The SETI League, Inc.
433 Liberty Street, PO Box 555, Little Ferry NJ 07643 USA
voice (201) 641-1770; fax (201) 641-1771; URL
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"We Know We're Not Alone!"