Vastness
Bluelight Crew
EDIT: This thread was previously entitled "Great Filters of the Fermi Paradox - what are they?" but I have renamed it because I think I have kind of over-complicated what I was actually hoping to discuss.
I've posted this is Philosophy & Spirituality because, as I see it, one the technology stuff is out of the way, the primary issues affecting the stability of a civilisation on cosmological timescales - millenia to millions (or even billions) of years - are, after a point, going to be cultural - and these cultural issues will probably be unrecognisable to use, mere denizens of this single-planet baby civilisation that we are a part of. So the primary interesting philosophical meat of this topic would be discussing the culture and the mindset that persists within such a culture of beings who without losing their individuality entirely, have been able to establish a stable society that remains stable over inconcievably vast timescales and inconceivably vast distances.
I'll leave everything I wrote below too as it gives a kind of primer to my own thought processes here...
This is a topic I find very interesting and it's been discussed a few times in this forum although maybe not in the most appropriate threads.
I feel like there is a fairly widespread misinterpretation of what the Fermi Paradox actually is which causes people to dismiss it offhand, so before we get started with the actual discussion I'd just like to clear that up. The Fermi Paradox is nothing more than a conceptual basis for further discussion about how common or uncommon life is in the universe, and of that life, the likelihood of any given species evolving and developing technology to the point that they can be considered a truly spacefaring civilisation. It says, in summary "If the universe is so big and old, where are all the alien civilisations?"
Obviously, the paradox is an illusion - evidently, we are here, life evolves sometimes (at least once, anyway). We do not, however, see emissions from broadcasting civilisations or any evidence of megascale engineering from high energy expenditure civilisations - as we would expect to see had a species evolved , say, a couple million years before us (not entirely implausible), developed space travel, and elected to start colonising nearby stars. Either this has not happened (a species evolved in our past that had the capability to do this, or it did happen, but prior to us developing the technology to detect them, they decided for whatever reason to hide themselves - or, possibly, destroy themselves - ie, they failed to surpass a Great Filter to become a truly spacefaring civilization.
So obviously, there are filters - life does appear to be rare, and the galaxy is not swarming with aliens, or at least, waste heat signatures, possible leaky signals, or whatever might conceivably indicate the presence of incredibly advanced alien races, have not reached us in the relatively short blip of time that we would have been able to detect them.
Ergo, there are filters preventing alien civilisations from being so numerous that we couldn't have helped but spot a ship, or just a signal with an unmistakably inhuman and unmistakably artificial design by now. I'm just trying to stress this point so we don't get too bogged down in the "what ifs" that, IMO, aren't really relevant necessarily and just kill any further discussion (like if all aliens quickly develop tech which makes them entirely invisible to us - I would say that even if this were a likely practice, it's not likely that every species would do this).
So can we accept that there are filters?
Good. But what are the filters?
As I see it, the most obvious filters are roughly as follows:
What other filters could there be, either in the past or in the distant future assuming we get past number 6?
Would be very interested to hear all of your inputs!
I've posted this is Philosophy & Spirituality because, as I see it, one the technology stuff is out of the way, the primary issues affecting the stability of a civilisation on cosmological timescales - millenia to millions (or even billions) of years - are, after a point, going to be cultural - and these cultural issues will probably be unrecognisable to use, mere denizens of this single-planet baby civilisation that we are a part of. So the primary interesting philosophical meat of this topic would be discussing the culture and the mindset that persists within such a culture of beings who without losing their individuality entirely, have been able to establish a stable society that remains stable over inconcievably vast timescales and inconceivably vast distances.
I'll leave everything I wrote below too as it gives a kind of primer to my own thought processes here...
This is a topic I find very interesting and it's been discussed a few times in this forum although maybe not in the most appropriate threads.
I feel like there is a fairly widespread misinterpretation of what the Fermi Paradox actually is which causes people to dismiss it offhand, so before we get started with the actual discussion I'd just like to clear that up. The Fermi Paradox is nothing more than a conceptual basis for further discussion about how common or uncommon life is in the universe, and of that life, the likelihood of any given species evolving and developing technology to the point that they can be considered a truly spacefaring civilisation. It says, in summary "If the universe is so big and old, where are all the alien civilisations?"
Obviously, the paradox is an illusion - evidently, we are here, life evolves sometimes (at least once, anyway). We do not, however, see emissions from broadcasting civilisations or any evidence of megascale engineering from high energy expenditure civilisations - as we would expect to see had a species evolved , say, a couple million years before us (not entirely implausible), developed space travel, and elected to start colonising nearby stars. Either this has not happened (a species evolved in our past that had the capability to do this, or it did happen, but prior to us developing the technology to detect them, they decided for whatever reason to hide themselves - or, possibly, destroy themselves - ie, they failed to surpass a Great Filter to become a truly spacefaring civilization.
So obviously, there are filters - life does appear to be rare, and the galaxy is not swarming with aliens, or at least, waste heat signatures, possible leaky signals, or whatever might conceivably indicate the presence of incredibly advanced alien races, have not reached us in the relatively short blip of time that we would have been able to detect them.
Ergo, there are filters preventing alien civilisations from being so numerous that we couldn't have helped but spot a ship, or just a signal with an unmistakably inhuman and unmistakably artificial design by now. I'm just trying to stress this point so we don't get too bogged down in the "what ifs" that, IMO, aren't really relevant necessarily and just kill any further discussion (like if all aliens quickly develop tech which makes them entirely invisible to us - I would say that even if this were a likely practice, it's not likely that every species would do this).
So can we accept that there are filters?

As I see it, the most obvious filters are roughly as follows:
- emergence of life in the first place from abiotic matter, requires a certain unique and rare type of planet, moon, or asteroid with sufficient energy input and chemical content...
- development of life from self-replicating molecules, single cells, into macroscopic organisms
- development of high intelligence, and possession of adequate maniple appendages for fine manipulation of the environment
- development of technology, and living on a planet which allows this phase of development to thrive - for example, water worlds, gas giants if anything could live there, planets extremely metal-poor, would all have major and possibly insurmountable challenges to harnessing electricity, fire, and thus progressing to computers and the technological leap that allows
- development of the technology to leave their homeworld - again, planets with gravity just a little higher than the Earths, poor in the kind of volatiles that make good propellants, or even in a very crowded system like a moon that passed through the debris of it's parent's ring system, would make this very difficult - possibly prohibitively so - even in the presence of a highly advanced culture it would be possible for a species to be essentially trapped on their homeworld even while developing a highly advanced understanding of the universe beyond
- overcoming tribalism - tribalism, or something like it, ie, the drive to survive, compete, and wage war on our competitors - can be argued to be something intrinsic to almost any species that has competed it's way to the apex of it's home planet's ecosystem - as, for better or worse, we humans have - but this same tribalism, once the homeworld is known, fairly culturally homogenous or moving towards it, and there's no one left to fight with who is truly "other", may not be something that can be just switched off, or overcome, as we manufacture reasons to create new divisions that divide us. This same tribal instinct that has given us so much and is no doubt a significant contributor to the might of human ingenuity, could well be the undoing of many a technologically capable, almost next level civilisation... I would actually argue that this is the Great Filter which we are facing right now... The first 5 are handled - but there is a lot of uncertainty in the world - we have the knowledge, resources, and technology to make it better and create a bright future for all of us. But we may well destroy ourselves before this can happen... Maybe this is our inescapable fate and the solution to the Fermi Paradox - intelligent species always destroy themselves. But I hope we overcome it.
- development of technologies to facilitate reliable interstellar travel and extrasolar settlement - maybe this is just not possible, despite what all our science fiction and scientific optimists would have us believe... it seems to me this is surely a filter of some kind, but whether it is a "Great Filter", with almost insurmountable odds of being achieved before succumbing to #6, for example - is up for debate...
What other filters could there be, either in the past or in the distant future assuming we get past number 6?
Would be very interested to hear all of your inputs!

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