Remember Templeton Prize-winning astronomer Martin Rees? Looking back at what speculative cosmology was like a decade ago, I ran into this opinion piece he wrote in 2003 on why the fact that we never hear from space aliens doesn’t mean anything. A couple of remarks stood out, especially,
Any claims that advanced life is widespread must, of course, confront the famous question posed by the great physicist Enrico Fermi: “Why aren’t the aliens here?” Why haven’t they visited Earth already, or at least manifested their existence in a way that leaves us in no doubt? This argument gains further weight when we realise that some stars are billions of years older than our sun: if life were common, its emergence should have had a head start on planets around these ancient stars.
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The Fermi paradox is not entirely compelling. Indeed, a recent book by Stephen Webb claims to offer 50 different counter-arguments. ET’s signal may simply have been missed, for example. Webb concludes the best option may be that we really are alone. But as often in science, opinions are most strongly polarised when evidence is minimal; we know far too little about how life began, even on Earth, to offer confident odds. Moreover, no matter how heavy the odds against finding it, searches for extraterrestrial intelligence are surely a worthwhile gamble because of the huge philosophical import of any detection.
A manifestly artificial signal – an ultra-narrow-band radio transmission, or a message as boring as a set of prime numbers or the digits of in binary notation – would convey the momentous message that intelligence, though not necessarily consciousness, is not unique to the Earth and has evolved elsewhere, and that concepts of logic and physics are not peculiar to the type of biological hardware contained within human skulls.
First, if fifty different counter-arguments are needed, the most likely situation is that we are indeed alone.
It rather reminds one of Albert Einstein’s comment, on hearing of a book called One Hundred Authors Against Einstein: “Why 100 authors? If I were wrong, then one would have been enough!”
Second, why would we have any reason to believe that, absent space aliens, concepts of logic and physics are “peculiar to the type of biological hardware contained within human skulls.” Do two and two only make four because we think it’s true? Would gravity not exist if it had no impact on us?
The best argument for space aliens right now is the impact they seem to have on the minds of otherwise intelligent people. That is one of the things I learned from researching my recent series on cosmology. Unfortunately, even that does not seem to be a good enough argument; one could make the same claim for Bigfoot and the ghost of Lady Jane Grey.
See also:
What has materialism done for science?
Big Bang exterminator wanted, will train
Copernicus, you are not going to believe who is using your name. Or how.
“Behold, countless Earths sail the galaxies … that is, if you would only believe”
Don’t let Mars fool you. Those exoplanets teem with life!