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There's a lot of talk about the great filter this, and the great filter that. Even if life is abundant, what gives you the impression that civilization level in

There's a lot of talk about the great filter this, and the great filter that. Even if life is abundant, what gives you the impression that civilization level intelligence would be? Out of all the species that ever roamed the earth, only a single one has reached this point. Perhaps it's an absolutely incredible fluke or glitch in our biology that is one in a [insert astronomical number]. It's tempting to think something in the lines of "oh but if it happened here in our little shitty solar system, it can't be very special". But that's more or less the anthropic principle.

profmonocle 6y ago
The hypothesis also makes a huge assumption: that if intelligent civilizations were common, they would be detectable by us. The radio waves emitted by our own civilization don't go that far (compared to the distance between stars) before becoming nearly indistinguishable from background noise.
- rsynnott 6y ago
  Also, they’re dying. Earth is probably less noisy now that 50 years ago.
  - umanwizard 6y ago
    Why is that the case?
    - rsynnott 6y ago
      As I understand it, the most visible stuff would be TV signal and over the horizon radar. TV signals have gotten less powerful, over the horizon radar is less of a big deal than it used to be. In another 50 years, will terrestrial TV, or any high power terrestrial radio, be a thing at all?
    - jodrellblank 6y ago
      It’s wasteful to spend the power to broadcast up into the sky when no viewers are up there; more focused directional transmitters, more sensitive receivers which allow lower power signals, more information sent over cable and fibre optic and undersea transmission lines and point-to-point satellite, more microwave and laser links compared to spam-everywhere radio broadcasts.
- garmaine 6y ago
  On the other hand, stars are extremely wasteful. A technological civilization will, eventually, encase their sun in an energy extracting Dyson swarm. So why isn't the sky full of dim uniform-distribution infrared blobs?
  - JauntTrooper 6y ago
    Would they still be detectable? Or could they capture enough energy that the stars would be barely noticeable, like trying to find a brown dwarf?
    - saberdancer 6y ago
      I followed Tabby's Star news for a while (star that showed massive dips, speculation was that it is a dyson sphere being built). Most scientists believe that even if the star is encased in Dyson sphere that there would be excess infrared emissions as the sphere would need to vent heat. It would be hotter than surrounding space and thus visible. They are thus trying to detect such stars with higher mass and IR excess than expected, but so far there are not many candidates.
    - garmaine 6y ago
      You cannot simply absorb all the energy of the star and never emit it. The waste heat has to go somewhere. An efficient Dyson sphere would still emit lower energy infrared radiation in a way that would be detectable from out space-based observatories.
  - Filligree 6y ago
    Because there's no other intelligent life out there. You know that. But it bears mention, for others following along, that rampant artificial intelligence or similar does not count as a great filter candidate, because it would be just as visible as the life it's replacing. That doesn't leave a lot of fast-acting filters that could still be in our future, to be honest. Nuclear war? Sure, but we've avoided it too long for that to be a good one either.
    - 6y ago
- laretluval 6y ago
  Some proportion of civilizations would develop to the point that their signals are detectable to us (this is a parameter in the Drake equation). Since we haven't detected anyone, there must be some problem in reaching that point.
  - StanislavPetrov 6y ago
    Unless: 1) The Drake Equation is wrong and its difficult to detect advanced civilizations. 2) We have detected other civilizations but we haven't recognized their signals properly. 3) We have detected other civilizations and the government is concealing it from us. 4) The UFO footage released recently by the Pentagon is proof of detection.
    - nckthrn 6y ago
      IANAA, but I have always wondered if dark matter / energy is an explanation for 2)
- yreg 6y ago
  Our planetary system (formed 4.5B years ago) is comparatively late to the game. The waves from older civilizations should have been everywhere by now. If they were expansionist, they should have even collonised the whole Galaxy long ago.
cmrdporcupine 6y ago
100% this. Unfortunately people still think very teleologically, as if nature works in a progressive fashion towards some structured end; this tendency is deep in western thought all the way back to Plato (and probably beyond), and it's all over science fiction.
- alquemist 6y ago
  The core observation is that organisms with an ability to model the Universe, even if imprecisely and in a tiny space-time neighborhood, increases the chances of survival. See the ubiqutous living beings with a nervous system. The hypothesis is that increased precision and/or size of the prediction bubble is correlated with survival fitness, which, in the limit, gives raise to beings with a God-like ability to predict the Universe. It's a relatively simple inductive argument.
  - ball_of_lint 6y ago
    Even if it is true that "in the limit" increased foresight implies increased fitness, it doesn't necessarily follow that being with God-like foresight exist. That said, IMO there's a lot of things that could confound the usefulness of increased foresight. After a certain point (which humanity has likely passed) foresight is not a particularly visible measure of fitness except in those rare extinction events that require significant cooperation to survive. I suppose that even given that foresight is the most valuable trait for long-term survival of a species, it's very rare that it is selected for beyond a certain point because the events that it allows a species to survive are too rare to be selected against.
jules-jules 6y ago
If I remember the argument by Bostrom correctly, finding life would increase the probability that one or possibly a number of great filters are further up in the evolutionary development of life, as a corollary this would mean a higher likelihood that such filters still lie ahead of us.
- mekkkkkk 6y ago
  Bostroms original article was about how finding intelligent life would be concerning. He even goes into detail about how a great filter could be somewhere in the evolutionary steps between simple life to complex, intelligent, civilization-building life. My point is that the "omg great filter confirmed" is a bit premature, and is a misunderstanding of the argument. EDIT: Re-reading your comment, maybe this isn't contradictory to your point. Finding out that there is an abundance of life does indeed eliminate at least one major candidate great filter. I'm not sure that would somehow move the odds of a real one being ahead of us though.
  - jules-jules 6y ago
    It's not about intelligent life per se; rather the more advanced life we find, the more concerning for the future it would be, as the likelihood of a great filter being located ahead of us increases, precisely because we haven't been able to detect more advanced life forms than us. Another interesting consideration is the Dark Forest, of course. I dug out the section in Bostrom's paper: "What has all this got to do with finding life on Mars? Consider the implications of discovering that life had evolved independently on Mars (or some other planet in our solar system). That discovery would suggest that the emergence of life is not a very improbable event. If it happened independently twice here in our own back yard, it must surely have happened millions times across the galaxy. This would mean that the Great Filter is less likely to occur in the early life of planets and is therefore more likely still to come. If we discovered some very simple life forms on Mars in its soil or under the ice at the polar caps, it would show that the Great Filter must exist somewhere after that period in evolution. This would be disturbing, but we might still hope that the Great Filter was located in our past. If we discovered a more advanced life‐form, such as some kind of multi‐cellular organism, that would eliminate a much larger stretch of potential locations where the Great Filter could be. The effect would be to shift the probability more strongly to the hypothesis that the Great Filter is ahead of us, not behind us. And if we discovered the fossils of some very complex life form, such as of some vertebrate‐like creature, we would have to conclude that the probability is very great that the bulk of the Great Filter is ahead of us. Such a discovery would be a crushing blow. It would be by far the worst news ever printed on a newspaper cover."
noisy_boy 6y ago
So you are saying, we are special for real? :)
yreg 6y ago
There are many candidates for the Great Filter, in fact what you are proposing (it's unlikely to evolve civilization-level intelligence) is one of them.

profmonocle 6y ago

The hypothesis also makes a huge assumption: that if intelligent civilizations were common, they would be detectable by us. The radio waves emitted by our own civilization don't go that far (compared to the distance between stars) before becoming nearly indistinguishable from background noise.

rsynnott 6y ago
Also, they’re dying. Earth is probably less noisy now that 50 years ago.
- umanwizard 6y ago
  Why is that the case?
  - rsynnott 6y ago
    As I understand it, the most visible stuff would be TV signal and over the horizon radar. TV signals have gotten less powerful, over the horizon radar is less of a big deal than it used to be. In another 50 years, will terrestrial TV, or any high power terrestrial radio, be a thing at all?
  - jodrellblank 6y ago
    It’s wasteful to spend the power to broadcast up into the sky when no viewers are up there; more focused directional transmitters, more sensitive receivers which allow lower power signals, more information sent over cable and fibre optic and undersea transmission lines and point-to-point satellite, more microwave and laser links compared to spam-everywhere radio broadcasts.
garmaine 6y ago
On the other hand, stars are extremely wasteful. A technological civilization will, eventually, encase their sun in an energy extracting Dyson swarm. So why isn't the sky full of dim uniform-distribution infrared blobs?
- JauntTrooper 6y ago
  Would they still be detectable? Or could they capture enough energy that the stars would be barely noticeable, like trying to find a brown dwarf?
  - saberdancer 6y ago
    I followed Tabby's Star news for a while (star that showed massive dips, speculation was that it is a dyson sphere being built). Most scientists believe that even if the star is encased in Dyson sphere that there would be excess infrared emissions as the sphere would need to vent heat. It would be hotter than surrounding space and thus visible. They are thus trying to detect such stars with higher mass and IR excess than expected, but so far there are not many candidates.
  - garmaine 6y ago
    You cannot simply absorb all the energy of the star and never emit it. The waste heat has to go somewhere. An efficient Dyson sphere would still emit lower energy infrared radiation in a way that would be detectable from out space-based observatories.
- Filligree 6y ago
  Because there's no other intelligent life out there. You know that. But it bears mention, for others following along, that rampant artificial intelligence or similar does not count as a great filter candidate, because it would be just as visible as the life it's replacing. That doesn't leave a lot of fast-acting filters that could still be in our future, to be honest. Nuclear war? Sure, but we've avoided it too long for that to be a good one either.
  - 6y ago
laretluval 6y ago
Some proportion of civilizations would develop to the point that their signals are detectable to us (this is a parameter in the Drake equation). Since we haven't detected anyone, there must be some problem in reaching that point.
- StanislavPetrov 6y ago
  Unless: 1) The Drake Equation is wrong and its difficult to detect advanced civilizations. 2) We have detected other civilizations but we haven't recognized their signals properly. 3) We have detected other civilizations and the government is concealing it from us. 4) The UFO footage released recently by the Pentagon is proof of detection.
  - nckthrn 6y ago
    IANAA, but I have always wondered if dark matter / energy is an explanation for 2)
yreg 6y ago
Our planetary system (formed 4.5B years ago) is comparatively late to the game. The waves from older civilizations should have been everywhere by now. If they were expansionist, they should have even collonised the whole Galaxy long ago.

cmrdporcupine 6y ago

100% this. Unfortunately people still think very teleologically, as if nature works in a progressive fashion towards some structured end; this tendency is deep in western thought all the way back to Plato (and probably beyond), and it's all over science fiction.

alquemist 6y ago
The core observation is that organisms with an ability to model the Universe, even if imprecisely and in a tiny space-time neighborhood, increases the chances of survival. See the ubiqutous living beings with a nervous system. The hypothesis is that increased precision and/or size of the prediction bubble is correlated with survival fitness, which, in the limit, gives raise to beings with a God-like ability to predict the Universe. It's a relatively simple inductive argument.
- ball_of_lint 6y ago
  Even if it is true that "in the limit" increased foresight implies increased fitness, it doesn't necessarily follow that being with God-like foresight exist. That said, IMO there's a lot of things that could confound the usefulness of increased foresight. After a certain point (which humanity has likely passed) foresight is not a particularly visible measure of fitness except in those rare extinction events that require significant cooperation to survive. I suppose that even given that foresight is the most valuable trait for long-term survival of a species, it's very rare that it is selected for beyond a certain point because the events that it allows a species to survive are too rare to be selected against.

jules-jules 6y ago

If I remember the argument by Bostrom correctly, finding life would increase the probability that one or possibly a number of great filters are further up in the evolutionary development of life, as a corollary this would mean a higher likelihood that such filters still lie ahead of us.

mekkkkkk 6y ago
Bostroms original article was about how finding intelligent life would be concerning. He even goes into detail about how a great filter could be somewhere in the evolutionary steps between simple life to complex, intelligent, civilization-building life. My point is that the "omg great filter confirmed" is a bit premature, and is a misunderstanding of the argument. EDIT: Re-reading your comment, maybe this isn't contradictory to your point. Finding out that there is an abundance of life does indeed eliminate at least one major candidate great filter. I'm not sure that would somehow move the odds of a real one being ahead of us though.
- jules-jules 6y ago
  It's not about intelligent life per se; rather the more advanced life we find, the more concerning for the future it would be, as the likelihood of a great filter being located ahead of us increases, precisely because we haven't been able to detect more advanced life forms than us. Another interesting consideration is the Dark Forest, of course. I dug out the section in Bostrom's paper: "What has all this got to do with finding life on Mars? Consider the implications of discovering that life had evolved independently on Mars (or some other planet in our solar system). That discovery would suggest that the emergence of life is not a very improbable event. If it happened independently twice here in our own back yard, it must surely have happened millions times across the galaxy. This would mean that the Great Filter is less likely to occur in the early life of planets and is therefore more likely still to come. If we discovered some very simple life forms on Mars in its soil or under the ice at the polar caps, it would show that the Great Filter must exist somewhere after that period in evolution. This would be disturbing, but we might still hope that the Great Filter was located in our past. If we discovered a more advanced life‐form, such as some kind of multi‐cellular organism, that would eliminate a much larger stretch of potential locations where the Great Filter could be. The effect would be to shift the probability more strongly to the hypothesis that the Great Filter is ahead of us, not behind us. And if we discovered the fossils of some very complex life form, such as of some vertebrate‐like creature, we would have to conclude that the probability is very great that the bulk of the Great Filter is ahead of us. Such a discovery would be a crushing blow. It would be by far the worst news ever printed on a newspaper cover."

noisy_boy 6y ago

So you are saying, we are special for real? :)

yreg 6y ago

There are many candidates for the Great Filter, in fact what you are proposing (it's unlikely to evolve civilization-level intelligence) is one of them.