For all we know, it takes a whole universe banging molecules together before metabolizing self-replicating life randomly arises. If it has only emerged one time in the entire universe, nothing would look different to us than it does right now.
Or maybe it happens all the time. But with only one sample, we have no data either way.
> But with only one sample, we have no data either way.
Sure we do, that one instance of life pushes the needle in favor of life. A fun exercise is to imagine or visualize the concept of nothingness, as far as you can take it. Eventually you realize even the "idea of nothingness" negates the meaning of "nothingness." You reach a paradox in awareness that you're incapable of resolving because to do so would mean the idea didn't exist in the first place. Applying it to life, the existence of life negates the existence of no-life, and increases the probability in our favor.
Functionally I think life is more commonplace than anyone realizes, and we're probably just incapable of understanding life outside of our perception of reality.
We know life is not nonexistent, but that's all we know.
Given that life exists, here are two possibilities: life is common but we just haven't seen other life yet, or life is unique and necessarily we're it. Since those two possibilities look exactly the same to us, what data can we have to prefer either one?
If we ever did see other life, then we could be confident that it's everywhere. But without seeing it, we don't know. We can only guess, according to our personal preferences.
In fact, I'd go further. Compared to not looking at all, looking for life and not finding it increases the likelihood that we're alone. Maybe not by that much, since astronomy isn't all that good yet, but the more we look without finding, the more rare we'll know life to be.
Excellent thinking, unassailable logic. I'd go a step further to state we truly are incapable of "understanding" nothingness, we're not constructed to know (in any sense) what that state is like. Precisely the reason we can't truly anticipate death, it's completely foreign to our sensibilities.
Humans evince resistance to an obvious reality, we can't know what is unknowable, that is to say, that which we are incapable of experiencing. I can't know what another person experiences let alone some living entity built according to some alternate template.
Logic dictates a conclusion that other life likely exists in the universe. Also the odds favor that we can't know what it is given the intrinsic limits to what humans are capable of knowing.
So we only have one data point of a planet producing what will quite possibly be a spacefaring civilization or, in the very least, one able to comprehend as such.
But if you accept that the Dyson Swarms are a likely outcome then we have a while bunch of negative data points in systems within even thousands of light years of us.
That then brings into focus the hypothesis about Dyson Swarm. Such a thing can be built incrementally, requires no material stronger than stainless steel and requires no energy tech beyond solar power. It is a massive engineering challenge to be sure but not requiring new physics is significant.
Or maybe it happens all the time. But with only one sample, we have no data either way.