From the Paramus Post, a story by Bruce Lieberman looks at contrasting views of SETI:
On both sides of the SETI debate, scientists acknowledge that what’s certain is the limit of what they know.
“I personally think that because the origin of life is an extremely difficult process … even simple life is very rare in the galaxy,” Zuckerman said. “But I have no particular claims other than my gut feeling.”
Shostak has publicly debated Zuckerman on the issue, and he remains confident that future searches will make contact. “I doubt that I would conclude that nobody’s out there,” he said. “To me that seems like a last-resort option. But that’s simply my feeling on the matter. And my feeling on the matter … actually means nothing because what counts is what you can find.
“That’s the difference between science and belief.”
A quick overview of the topic, available here.