> "Would it surprise me, my interlocutor persisted, if SETI fails to find another civilization in my lifetime?"<p>On its face that's a rather silly question; if I'm in a position to reflect on whether SETI has found a civilization then my life is not over. If my life is over then I am not in a position to experience surprise. So it seems to me anyway; I guess if my life <i>were</i> over and I experienced anything I'd certainly be surprised - it just wouldn't be much to do with SETI's discoveries or lack thereof :D<p>Anyway setting that aside, and as nothing more than an interested observer on the topic, it does seem to me exceedingly suspicious that the more we learn about Earth's early history the earlier we push back the origins of life. It all started up <i>very</i> close to the solidification of the surface! So one has to suspect that either panspermia happened or life is relatively easy to kick start.<p>Even if you assume that life is only easy to kick start on planets more-or-less identical to Earth (similar mass, temperature range, supply of elements, star type etc) there's going to be a literally astronomical number of candidates.