Seth Shostak

The thing to keep in mind is that we're still in the very early days when it comes to the search for extraterrestrial intelligence. Saying there's a silence is a bit like if Columbus, looking to discover a new continent, only sailed 10 miles off the coast of Spain before turning back to say, 'Nothing out there!'

Clearly, unless thinking beings inevitably wipe themselves out soon after developing technology, extraterrestrial intelligence could often be millions or billions of years in advance of us. We're the galaxy's noodling newbies.

It's hard to imagine anything more interesting than learning how we're woven into the enormous tapestry of existence. Where did our universe come from? How special is our world, and how special are we? We allocate tens of billions of dollars annually to NASA, NSF and academia in search of the answers.

Are we the only members of the Galaxy that can actually understand what a galaxy is? Could Homo sapiens really be the pinnacle of Creation - the cleverest critters in the cosmos? If we learn the answer is 'no,' that would affect our philosophies forever.

The fact that we can't easily foresee clues that would betray an intelligence a million millennia farther down the road suggests that we're like ants trying to discover humans. Ask yourself: Would ants ever recognize houses, cars, or fire hydrants as the work of advanced biology?

Humans have existed only for the last 0.001 percent of cosmic time. All of which says that - unless the Homo sapiens brain is the one-and-only instance of cogitating machinery - nearly all the intelligence that's out there is beyond our level. And that intelligence is more than just a little bit beyond.

Sure, our three-pound brains might be inadequate to understand the universe. But perhaps they're just good enough to build something that can.