> to it being so rare that our existence is indeed special.
Which is possible but hardly reasonable . . .
Many in STEM would argue that it's reasonable to assume we're not at all special.
Which is possible but hardly reasonable . . .
Many in STEM would argue that it's reasonable to assume we're not at all special.
The reasonable assumption as with most things is that we aren't special, yet the data increasingly does not appear to reflect that. Unlike with detecting exoplanets, blaming our sensors only makes this discrepancy worse.
Unless you're trying to make the argument that we haven't found life because we're looking for specifically Earth-like life, in which case I'd just say that it's more rational with our current technology to focus on the kind of life we definitely know can exist rather than hypothetical biochemstries we can't realistically test. It isn't even as if the conditions we're setting are especially extreme, a planet in a goldilocks zone of a relatively stable star with an atmosphere and signatures of water and potentially significant amounts of oxygen.
It relates to intelligent lifeforms that show themselves in ways we can recognise.
It has little bearing on the question of life elsewhere - a starfish orbiting an exoplanet counts here.
Fermi was a little naive on the "space is big | communication is hard" front - before the James Cook expeditions life existed in Australia and yet the British monarchy hadn't received a single missive by Royal Mail from any of the numerous nations within Australia.
The methods of signalling long distances that we're aware of require focus and|or vast amounts of power and extremely long travel times; focus requires us to be targetted over a staggeringly large number of other solar systems, weilding vast amounts of power requires tech able to do so and not find other more efficient means, etc.
Those communicating across galaxies are doing so in ways we do not yet recognise, those with civilisations that cause their own suns to give them away are yet to be found as we have barely starting looking at a fraction of all the systems there are out there - JWT is good but it's barely been up a day in cosmic terms and there's much left to look at.
The rare earth hypothesis is much more rooted in first principles. The earth has a very rare combination of factors all of which are crucial to life as we know it, and likely anything we could recognize as life due to the factors life requires for maintaining its complexity and ability to self replicate and perpetuate. These are not limited to the specific nature of carbon, water, and oxygen in the Goldilocks zones, the necessity of a magnetosphere, in a very specific galactic structure in a specific part of such a galactic structure, making the specific envelope of Sol and earth with its unique tectonic geology, etc, all of which are literally necessary to evolve life. Other forms of life are theorized (silicon based, etc) but they have almost impossible requirements to assemble into structures complex enough with enough flow of energy without so much energy they fall apart. Every theorized xenobiology other than the one we have is likely impossible for pretty fundamental reasons. This doesn’t mean we have exhausted all possibilities or that nature won’t surprise us in crazy ways beyond our imagination, it just means life is almost certainly MUCH MUCH more rare than drakes equation lets on.
https://en.m.wikipedia.org/wiki/Rare_Earth_hypothesis
Again, I’m not saying life doesn’t exist outside earth. I’m saying we don’t know and despite really hard efforts to approach extraterrestrial life from every possible angle has been fruitless so far, even to the point we have no theories of life’s origins, how to detect life, and no open avenues that have any hope of such a discovery. At the moment it’s feeling less likely we will discover life outside the earth before we can reverse time (as we have done in simple time crystals). That should be daunting to our blind faith.
To my mind this should weigh on us as a burden. As long as we believe life exists elsewhere the loss of life on earth is sad, but ultimately inconsequential. If we are the seed of life in the practically observable universe, then we are the shepherd of the most amazing thing in all of creation. We have a responsibility to tend it, and IMO, spread it as far and wide as we can such that the universe does team with life and for the rest of all time life never feels alone.
That said, the entire universe as is appears to be in incredibly rare event, moreso than mere evolution.
We have no idea how rare the universe is because we can't compare it to anything. We can compare terrestrial species to all of the other terrestrial species we know of. This shows that some evolutionary trajectories and forms appear to be more or less frequent outcomes.
Good luck floating that past your typical theoretical astrophysicist, there are several quite different approaches to taking a stab at that one - all fall into can't be resolved either way basket though, I see your point.
fnordpiglet mentions the rare earth notion, I first came across that in the mid 70's reading an Asimov non fiction essay collection The Tragedy of the Moon which raised the importance(??) of having a moon to create tides to create intertidal zones to nudge life from water to land.
https://en.wikipedia.org/wiki/The_Tragedy_of_the_Moon
There's a long chain of chance that lies behind ourselves arriving where we are ... the argument can still be made (as it was by Douglas Adams) that "The universe is big. Really Big."
The latest JWT images convey just a smidgeon of how big with high res images of tiny arc areas of the night sky packed with tiny lights that are each galaxies the size of the milky way and more.
That's a lot of rolls of the dice out there.
Also, possible doesn’t mean plausible. Objects can teleport to the moon through quantum principles it’s just so unlikely it’s never actually happens in reality. Life may be such a vastly implausible thing that our existence is a miracle so improbable it beggars the imagination.