Most people are inclined to think that the universe is teeming with life, because the universe is just so darned big. But if so, where are they? That's the question physicist Enrico Fermi famously asked, and has since become known as Fermi's paradox.
One of my first articles concerned the search for extra-terrestrial intelligence. It has been interesting to see new knowledge come in on that front since I wrote that article over a decade and a half ago. This article in the New York Times provides a nice overview from a more recent perspective, such as the discovery of extrasolar planets (none were known when I wrote my original article).