Astrobiologist Caleb A. Scharf, takes issue with Harvard astronomer Avi Loeb: Skepticism about ET isn’t just conservatism, he says, it’s experience. Scientists he says, are cautious with good reason. There are many weird natural phenomena like Oumuamua out there.
Here’s another way of looking at it, from information theory: The artifact or signal of an intelligent being should show “specified complexity. That is,
“Specified complexity: A long sequence of random letters is complex without being specified [it is hard to duplicate but it also doesn’t mean anything]. A short sequence of letters like “so,” is specified without being complex. [It means something but what it means is not very significant by itself]. A Shakespearean sonnet is both complex and specified. [It is both complex and hard to duplicate and it means a lot in a few words]”
That’s what we should be looking for in signals from intelligent beings — orderly patterns that hold meanings not found in inanimate nature.
If a roommate comes home and finds Scrabble letters on the board spelling out: IT’S YOUR TURN TO DO THE DISHES TONIGHT, he will hardly suppose that the arrangement resulted from someone dumping the bag of letters on the board.
If we can find signals like that, they will be hard to argue with. Meanwhile, informed skepticism is best.News, “Astrobiologist cautions against jumping the gun in spotting ET” at Mind Matters News
You may also wish to read: Astrophysicist warns: The aliens may be boring or unreachable. Researchers are taking the emissions from the vicinity of exoplanet Proxima B seriously. But if it is truly a technological signal, what would follow? Science fiction would be prophetic in the sense that Proxima B might show that They’re Out There. But maybe too optimistic about our chances of making contact.