The Great Filter

version

Who loves ya, baby?
I've always found this equal parts fascinating and ominous, the thought that we haven't contacted any form of extraterrestrial life because every civilization that's existed in the universe has reached the point we are now then collapsed before being able to get off the planet.

https://en.wikipedia.org/wiki/Great_Filter

With no evidence of intelligent life other than ourselves, it appears that the process of starting with a star and ending with "advanced explosive lasting life" must be unlikely. This implies that at least one step in this process must be improbable. Hanson's list, while incomplete, describes the following nine steps in an "evolutionary path" that results in the colonization of the observable universe:

1) The right star system (including organics and potentially habitable planets)
2) Reproductive molecules (e.g. RNA)
3) Simple (prokaryotic) single-cell life
4) Complex (eukaryotic) single-cell life
5) Sexual reproduction
6) Multi-cell life
7) Tool-using animals with big brains
8) Where we are now
9) Colonization explosion

According to the Great Filter hypothesis at least one of these steps—if the list were complete—must be improbable. If it's not an early step (i.e., in our past), then the implication is that the improbable step lies in our future and our prospects of reaching step 9 (interstellar colonization) are still bleak. If the past steps are likely, then many civilizations would have developed to the current level of the human species. However, none appear to have made it to step 9, or the Milky Way would be full of colonies. So perhaps step 9 is the unlikely one, and the only things that appear likely to keep us from step 9 are some sort of catastrophe, an underestimation of the impact of procrastination as technology increasingly unburdens existence or resource exhaustion leading to the impossibility of making the step due to consumption of the available resources (like for example highly constrained energy resources).
 

sufi

lala
7 Hypothetical explanations for the paradox

7.1 Extraterrestrial life is rare or non-existent
7.2 No other intelligent species have arisen
7.3 Intelligent alien species lack advanced technology
7.4 Water world hypothesis
7.5 It is the nature of intelligent life to destroy itself
7.6 It is the nature of intelligent life to destroy others
7.7 Periodic extinction by natural events
7.8 Intelligent civilizations are too far apart in space or time
7.9 Lack of resources to spread physically throughout the galaxy
7.10 Lack of desire to live on planets
7.11 It is cheaper to transfer information for exploration
7.12 Human beings have not existed long enough
7.13 We are not listening properly
7.14 Civilizations broadcast detectable radio signals only for a brief period of time
7.15 They tend to isolate themselves
7.16 Colonization is not the norm
7.17 Outcomes between all and nothing
7.18 They are too alien
7.19 Everyone is listening but no one is transmitting
7.20 Earth is deliberately not contacted
7.21 Earth is purposely isolated (planetarium hypothesis)
7.22 It is dangerous to communicate
7.23 They are here unacknowledged
 

version

Who loves ya, baby?
A distant fear which grips me from time to time is the thought of finding the ruins of a civilisation exactly like ours on another planet.
 

luka

Well-known member
Staff member
People like Bezos are making "conspiracy theories" like the breakaway civilisation and The Ark seem more and more plausible. The mega rich making plans to go off-planet and leaving the rest of us to burn. So long suckas!
 

Mr. Tea

Shub-Niggurath, Please
A distant fear which grips me from time to time is the thought of finding the ruins of a civilisation exactly like ours on another planet.
That would at least involve humanity reaching another start system, which presumably requires us to survive another few hundreds or thousands of years.

For me, the bleakest sci-fi idea possible is "What if we encounter another civilization that has much better tech than we do but is otherwise exactly like us?"

I mean, consider what's happened when cultures at radically different levels of technological development have encountered each other on earth within the last few hundred years.

The closest I've seen to this in fiction is probably the Predator franchise.
 

version

Who loves ya, baby?
That would at least involve humanity reaching another start system, which presumably requires us to survive another few hundreds or thousands of years.
The thing I find unsettling is the thought that it had all happened before and something went very wrong.
 

sufi

lala
hugely anthropocentric
as a species we have a well documented blindspot to our own insignificance in the universe.
my mate Galileo Galillei said so
we have no conception of the vastness or variety of "space", our pitiful reliance on our primitive scoping devices and terrestrial physics is about as fanciful and as useful as astrology in understanding all this
it's pretty obvious that our solar system is a dull backwater and that we have nothing whatsoever to offer an advanced intergalactic civilisation - we're flattering our selves yet again if we think we are even a useful source of nutrition or energy

personally i feel heartened by Oumuamua's stealthy close earth pass 2 years ago (and 40 days before anyone down here was even aware...)
 

Mr. Tea

Shub-Niggurath, Please
The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new dark age.
 
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Mr. Tea

Shub-Niggurath, Please
true but we should try and and recognise our limitations
Literally every single scientist worth their salt does this instinctively. It's an integral part of the scientific method - perhaps the most important single concept.
 

martin

----
Wasn't another possibility that they ARE picking up our messages - but, by the time they arrive, we've all been dead for hundreds of thousands of years?

I guess we could move to Keppler 22b, but you'd have to spend a similar amount of time getting there on some massive city ship. By the time you arrive, you could have mutated into freakish, fingerless, flat-headed monsters with IQs of 30, with zero memories of Earthman traditions, just howling like apes. And Keppler 22b could be populated by eugenicist supermodels.

"The mega rich making plans to go off-planet and leaving the rest of us to burn."

...while The Spectator argues that anyone opposing the idea is a jealous, loony-left snowflake. The good news is that, while we're trapped down here killing each other for a can of beans and riddled with skin cancer, and a 40-year old Greta Thunberg has to apologise for being caught saying off-camera "no, the trashy ones can stay in their ghettos with their plastic straws", there'll probably be a malfunction in the off-world colonisers' air supply, causing them to violently choke to death. Eat toxic Martian gas, yuppie scum!
 

Mr. Tea

Shub-Niggurath, Please
Wasn't another possibility that they ARE picking up our messages - but, by the time they arrive, we've all been dead for hundreds of thousands of years?

I guess we could move to Keppler 22b, but you'd have to spend a similar amount of time getting there on some massive city ship. By the time you arrive, you could have mutated into freakish, fingerless, flat-headed monsters with IQs of 30, with zero memories of Earthman traditions, just howling like apes. And Keppler 22b could be populated by eugenicist supermodels.

"The mega rich making plans to go off-planet and leaving the rest of us to burn."

...while The Spectator argues that anyone opposing the idea is a jealous, loony-left snowflake. The good news is that, while we're trapped down here killing each other for a can of beans and riddled with skin cancer, and a 40-year old Greta Thunberg has to apologise for being caught saying off-camera "no, the trashy ones can stay in their ghettos with their plastic straws", there'll probably be a malfunction in the off-world colonisers' air supply, causing them to violently choke to death. Eat toxic Martian gas, yuppie scum!
Why are you wasting your time on here when you should be writing this novel?!
 

luka

Well-known member
Staff member
hugely anthropocentric
as a species we have a well documented blindspot to our own insignificance in the universe.
my mate Galileo Galillei said so
we have no conception of the vastness or variety of "space", our pitiful reliance on our primitive scoping devices and terrestrial physics is about as fanciful and as useful as astrology in understanding all this
it's pretty obvious that our solar system is a dull backwater and that we have nothing whatsoever to offer an advanced intergalactic civilisation - we're flattering our selves yet again if we think we are even a useful source of nutrition or energy

personally i feel heartened by Oumuamua's stealthy close earth pass 2 years ago (and 40 days before anyone down here was even aware...)
This sounds a lot like clinical depression Sufi!
 
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