From: miner@kuhub.cc.ukans.edu
Newsgroups: sci.philosophy.meta
Subject: Re: Question about SETI:summary & response
Date: 10 Nov 92 06:22:25 CST
Organization: University of Kansas Academic Computing Services

In article <1992Nov8.182558.15459@mp.cs.niu.edu>, rickert@mp.cs.niu.edu (Neil Rickert) writes:
> In article <1992Nov8.105016.44517@kuhub.cc.ukans.edu> miner@kuhub.cc.ukans.edu writes:
> 
>>NEIL RICKERT:
>>
>>>    If, after a considerable period of time, say twenty more
>>>years, has been devoted to SETI, and still we have no reliable
>>>indication that intelligent life exists elsewhere in the universe, do
>>>you think this would have any effect on your personal philosophical
>>>outlook, and if so, what effect?  
>>
>>Since that is exactly the result I expect, it will not change my outlook
>>at all.
>>
>>>    And if not, do you therefore consider SETI philosophically
>>>irrelevant?
>>
>>I haven't thought about whether it should or should not be 
>>philosophically relevant.  I already consider SETI to be 
>>scientifically irrelevant.

This sounds a bit strong considering that (as I understand it) we
already have had seven or eight "wow" phenomena--apparently patterned
signals which (alas) have not been repeated.  For me personally, that
sort of thing maintains my interest; and it would seem, to me, to be
scientifically significant.

> Evolution has a large element of randomness.  Thus it is quite improbable
> that life elsewhere will develop as life on earth.  But, just for a
> moment, suppose it does.
> 
> There has been some form of life on earth for over 1 billion years.  If
> we manage to avoid a nuclear catastrophe, life on this planet may last
> one to three billions more years.
> 
> During that time, life on earth has been visible to a SETI type search
> for approx 50 years (since TV broadcasting).  After another 50 years
> our communication will be almost entirely by optic fiber links and low
> powered satellite links.  Thus we will be invisible again.

*Unless* we send a purposeful beacon.

> If life on earth is at all typical, then, visibility to SETI searches
> has a probability of about 100/2000000000.  These are not very good
> odds.  The galaxy might be teeming with life, yet it is highly improbable
> we would ever discover it with a SETI type program.
> 
> Some of the SETI exploration is based on other assumptions such as
> the idea that alien intelligences would have high powered beacons.
> These assumptions seem just as improbable.

This is the only part of your reasoning I don't understand.  It seems
to me that anything we would be willing to call intelligence would be
curious as we are to know whether it is alone, and would maintain a
beacon.  I always assumed that's what SETI is looking for, a
purposeful signal intended to be picked up.  *If* the galaxy is
"teeming with life" I don't see why that's improbable.

> Add to all of this the improbability of intelligent life on earth.  It
> is easy to imagine an evolution with insect, worms, etc, but no
> verterbrates.  Even with verterbrates, it is easy to imagine fish and
> amphibians, but no birds or mammals.  If you allow mammals, it is easy
> to imagine sheep, deer, lions, etc, but no apes.  And even with apes it
> is not at all clear why there is any necessity for homo-sapiens (and a
> powerful language ability) to evolve.  Human level intelligence most
> likely requires large size (to support sufficient processing power),
> high mobility (to allow a highly varied environment in which this
> intelligence has ecological benefits), a compact brain rather than a
> distributed system, to allow the possibility of developing associations
> between seemingly unrelated stimuli, and lots of luck to support the
> right type of language.
> 
> Thus, in summary, we may not be alone.  But we won't find the other guys
> with anything as naive as SETI.

I suggested in my original posting that new technology would evolve.
If SETI is now naive it may not remain that way.  I would expect the
approach to develop as findings (such as the "wows") come in.  All
research was naive initially, with hindsight, no?

As for the uniformitarian assumptions upon which SETI is based, it
seems to me they are part and parcel of the scientific method.  We may
have every reason to suspect that alien intelligence is nothing like
ours, yet we must assume that it is until we have evidence to the
contrary, which may be forthcoming as SETI develops.

Summarizing, then, it seems to me you may wrongly assume

	(a) a static rather than evolving SETI, and
	(b) that we are the only intelligence doing SETI.

NB: I'm not in hard science (just linguistics) and am coming at this
completely as a layman, so if I've overlooked something obvious, I
won't be too surprised.
-- 
-Ken <miner@kuhub.cc.ukans.edu> {Sometimes you have to look reality straight
 OPINIONS ARE MY OWN            {in the eye, and deny it. - G. Keillor