by Dan Wolaver
I once attended a lecture by a researcher involved in the Search for
Extra-Terrestrial Intelligence (SETI). The speaker said they
narrowed their search for signals by assuming any life would be similar
to that on Earth—water-based, evolving about 5 billion years after
their planet formed, etc. Therefore the team listened for
frequencies that aren't inhibited by a water-rich atmosphere, and those
coming from the direction of stars at least 5 billion years old.
I pictured all these beings around the Universe hunkered by their radios listening for somebody, but nobody talking. So I asked him whether SETI was broadcasting signals for aliens that are listening for us. "Oh, no." he said. "There'd be no government funding for that because we wouldn't get an answer from the the aliens for thousands of years." I said, "Since you're assuming aliens would be similar to us, then they won't be broadcasting either, and we're wasting our time listening."
I forget his response, but I think he was having a rather good time with his search, and he wasn't interested in my logic. My conclusion was that what we spend our time on doesn't have to be useful—just enjoyable. (And it's a nice bonus if someone is willing to fund it.)
And that's my philosophy.