we could be the oldest civilization in the Galaxy

--in spacesettlers@yahoogroups.com, "Combs, Mike" wrote:
> The difficulty with these and other similar explanations is that one
> must assume that EVERY technical species heads down the path
> proposed WITHOUT EXCEPTION.

True enough. In fact, I'm wondering why so many people, when
discussing the Fermi Paradox, have the mindset of a *single* factor
which is the proverbial one big reason for why interstellar
civilizations are so rare.

I think it's probably multiple factors, which collectively make it that
way.

As a simplified model: if there are 39 different factors, each of
which halves the number of interstellar civilizations in the galaxy,
then the number of interstellar civilizations in the galaxy would go
down to just 1 (the number of stars in the galaxy, ~400 billion,
divided by 2^39). Even though none of these is an absolute impass to
interstellar civilizations.

It is analogous to the life of a salmon: many millions born in the
stream, but only a few make it back to that stream to spawn again.
There isn't any one process which does all that elimination, but many
put together.