I wouldn't go that far...the universe is big, and it's becoming increasingly evident that planets are common. I would guess that sentient life is prevalent throughout the universe, although I have no way to assign a probability. But that's doesn't mean they've ever come here. The distances are just too vast.
But men are famous for entertaining hypotheses, which are part of our survival gear. And what is the source of all these speculation, these imaginings of alternatives to what we know.:? What is the mind? A ghost in the machine, or a product of the workings of the machine, and how is is to that it does have the ability to extrapolate far beyond what we see, hear, taste and smell? What is the nature of mathematics?Is it part of the machine, ot is to a product of the mind? And how is it that it seems to corrolate with our common perception of the world? And what is this world beyond the things we bump into right now?
I've never been that intrigued by questions of this nature...if it's not falsifiable, what's the point? One good engineer is worth a hundred philosophers!
And, of course, how is it that we are the only animals who think, who have this power of abstraction and detachment, so that even the savages have a sense of the immaterial?
That one's easy. Homo Sapiens in the most intelligent animal to ever evolve on this planet. Previous to our existence, animals simply didn't have the cognitive ability to think in this manner.
I think it pretty clear that we have only an inkling of what the whole universe is like. Relatively speaking, not that much more than what Ptolemy did. The pure positivism that Popper delineated gives us not much to deal with. As for falsifrication, the problem with evolution theory is that beginning with Darwin himself, it has been adopted as a kind of “theory of Everything.” It certainly can’t handle the basic question: how does intelligence look at itself?