Davoud wrote:
Glad you mentioned that -- I am again reminded that Fermi's question
remains unanswered: "Where are they?"

Of course it's been answered. There are just too many answers to choose
from.

One potential answer is, of course, that (to quote Sagan) "It's a big
cosmos." Lots of people seem to have confidence that the speed of light
is merely another barrier that humans, assuming they survive long
enough, will learn to overcome. But we have no particular reason to
think this is necessarily so. Maybe the interstellar distances really
are too great.

Another answer is that life develops fairly rapidly, but intelligence
doesn't. It took life a matter of just a few hundred million years to
develop on the Earth, but (at least from our provincial perspective)
evolution then stalled at unicellular organisms for three billion years.
If it had stalled another billion, more complex life forms might never
have evolved at all.

Yet another answer is that life is preciously rare, maybe to the point
of our being the only instance. Personally, I don't find that idea
particularly compelling, but it really doesn't matter what I find
compelling, of course!

PS : Belief vs faith? Now that is topic for another thread!

Or, we could just take it as read that that is a distinction without a
difference.

I think that depends an awful lot on context. Perhaps you disagree.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
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