This was mentioned in a weekly Friday Reflection from Touchstone. I had no idea the search had begun so early:
It began in concept as early as 1896 when Nikola Tesla suggested wireless electrical transmission to contact Martians. In 1899, he thought he had detected a signal from Mars—so he was listening. In 1924, an attempt to listen for Martians from the U. S. Naval Observatory was assisted by Admiral Eberle, chief of Naval Operations: a “National Radio Silence Day” was promoted with radios going silent for five minutes on the hour for 36 hours while a radio receiver in a dirigible floating 1.9 miles up listened for signals.
Personally I am of the opinion that if there are forms of life of a sort with which we could communicate, there is almost no possibility that we will ever know it. Everybody is familiar with the dogma asserted in favor of extraterrestrial life in general: that since there are [very very large number] of stars in the universe, it is so probable as to be all but certain that there will be life of the sort we would recognize as such, and that among those living things there will be some which we would recognize as being like us in having speech and intelligence.
The proponents of this idea, who usually present it as obvious, and even scientific, don't always mention the materialist and evolutionist axiom that underlies it: that life and consciousness are the products of chance working on matter. If you make that assumption, then it's reasonable to say that given enough stars and enough time, enough planets will form and develop in ways that can support life that enough of these will actually somehow give birth to life, and that enough of these life forms will evolve into intelligent beings that we will probably encounter them. It is all but certain, in this view, that they are out there, and highly probable that they will eventually contact us, or vice versa (or, of course, that this has already happened).
But if that axiom is not true, the conclusions are in doubt. If chance alone working on a whole heck of a lot of matter is not in fact the explanation for the existence of life and consciousness, then the only reasonable answer to the question "Does intelligent extraterrestrial life exist?" is "We do not know. And moreover we currently have no way of knowing." For my part, I'm firmly, even passionately, agnostic on the question--passionate because the materialist axiom is so little questioned, or even noticed..
If materialism as a philosophy is not the correct explanation of the world, then "scientific" pronouncements about extraterrestrial life are only speculation with no solid scientific value. I would argue further that the fact that the materialistic explanation of non-material phenomena such as human consciousness seems more plausible to most people in our time is a mere cultural prejudice. (I don't mean, of course, materialistic explanations for everyday material phenomena. If you're going to study the operations of the physical world, it would be unreasonable not to assume that material effects are produced by material causes. Simple experience and common sense tell us that that is the normal way of things.)
There's another big problem with the whole attempt to detect such life by any means we know. No one seems to believe that any nearby star systems have much potential for supporting life. And if there is life on a system 1,000 light years away, any evidence we receive would only tell us that there was life there 1,000 years ago. And our galaxy is estimated to be between 100,000 and 200,000 light years across. We are not likely to have a very interesting relationship with life forms with whom the exchange Hello. How are you? : We're fine. How are you? would take multiple thousands of years.
And travel across those distances? Well, it's easy to say "warp drive" or "hyperspace" or the more currently favored "wormhole," but these are just words that play the role in science fiction that magic plays in folk tales. The Millenium Falcon and a magic carpet are two instances of the same class of thing. I think I'm correct in saying that even the theoretical possibility of faster-than-light travel is vague, and that no technology implementing it can really even be imagined now--imagined as an actual engineering project, I mean.
Sure, all that could be proven mistaken and irrelevant tomorrow by some utterly unknown and unforeseen scientific breakthrough. But "you can't prove it will never be possible" is not a scientific position. I really don't have an opinion on whether there are other sentient material beings on other planets, but I do think it's unlikely that we'll ever meet them.
Now, the possibility of an entirely new order of being in which the spaces and distances we know do not limit us in the way that they now do is another matter entirely. But no possible technology can ever get us there.