In infinite wisdom Joseph Lazio answered:

"R" == Rich  <someone@somewhere.com> writes:

R> In infinite wisdom Joseph Lazio answered:

However, [that intelligent life might exist elsewhere is] enough to
justify SETI.  If you think that intelligent life may exist
elsewhere, the only way to find out is to look.

R> This does not necessarily follow. Even if life exists everywhere,
R> there is no guarantee that looking will show it. [...]  Who
R> knows. But SETI is a two part exercise, you've stated the
R> first. The second requirement is that ET is out there pointing a
R> radio dish in our direction. It's not enough that we look, they
R> must be broadcasting. If SETI finds nothing, it does not prove that
R> ET does not exist. And I see no basis for a reasonable expectation
R> that the current SETI will find anything.

The nature of science is to try to ask questions that can be answered
by experiment.

Exactly, and SETI is not an experiment. It's not research, it's a simple
search. There is a difference.

Existing and past SETI programs already set some,
albeit quite crude, limits on the existence of ET civilizations (e.g.,
Horowitz & Sagan 1993).

Methinks we'll hear this a lot over the years.

I'd prefer to have some hard data on the
number of ET civilizations, rather than rank speculation about all of
the possible reasons that we might not detect something.

If we had hard data, why do SETI?

If you prefer otherwise, well, so be it.

Eh?

Rich