The Great Filter, a possible explanation for the Fermi Paradox – interview with Robin Hanson

I grew up wondering about the nature of alien life, what it might look like, what they might do, and whether we will discover any time soon. Though aside from a number of conspiracy theories, and conjecture on Tabby’s Star, so far we have not discovered any signs of life out there in the cosmos. Why is it so?
Given the Drake Equation (which attempts to quantify the likelihood and detectability of extraterrestrial civilizations), it seems as though the universe should be teaming with life.  So where are all those alien civilizations?

The ‘L’ in the Drake equation (length of time civilizations emit detectable signs out into space) for a technologically advanced civilization could be a very long time – why haven’t we detected any?

There are alternative many explanations for reasons why we have not yet detected evidence of an advanced alien civilization, such as:
– Rare earth hypothesis – Astrophysicist ‘Michael H. Hart’ argues for a very narrow habitable zone based on climate studies.
– John Smart’s STEM theory
– Some form of transcendence

The universe is a pretty big place. If it’s just us, seems like an awful waste of space.Carl Sagan - 'Contact'

 

Our observable universe being seemingly dead implies that expansionist civilizations are extremely rare; a vast majority of stuff that starts on the path of life never makes it, therefore there must be at least one ‘great filter’ that stops the majority of life from evolving towards an expansionist civilization.

Peering into the history of biological evolution on earth, we have seen various convergences in evolution – these ‘good tricks’ include things like transitions from single cellular to multi-cellular (at least 14 times), eyes, wings etc. If we can see convergences in both evolution, and in the types of tools various human colonies created after being geographically dispersed, Deducing something about the directions complex life could take, especially ones that become technologically adept could inform us about our future.

The ‘Great Filter’ – should we worry?

The theory is, given estimates (including the likes of the Drake Equation), it’s not an unreasonable to argue that there should have been more than enough time and space for cosmic expansionist civilizations (Kardashev type I, II, III and beyond) to arise that are at least a billion years old – and that at least one of their light cones should have intersected with ours.  Somehow, they have been filtered out.  Somehow, planets with life on them make some distance towards spacefaring expansionist civs, but get’s stopped along the way. While we don’t specifically know what that great filter is, there have been many theories – though if the filter is real, seems that it has been very effective.

The argument in Robin’s piece ‘The Great Filter – Are We Almost Past It?’ is somewhat complex, here are some points I found interesting:

  • Life Will Colonize – taking hints from evolution and the behavoir of our human ancestors, it feasible that our ancestors will colonize the cosmos.
    • Looking at earth’s ecosystem, we see that life has consistently evolved to fill almost every ecological niche in the seas, on land and below. Humans as a single species has migrated from the African Savannah to colonize most of the planet filling new geographic and economic niches as requisite technological reach is achieved to take advantage of reproductively useful resources.
    • We should expect humanity to expand to other parts of the solar system, then out into the galaxy in so far as there exists motivation and freedom to do so.  Even if most of society become wireheads or VR addicted ‘navel gazers’, they will want more and more resources to fuel more and more powerful computers, and may also want to distribute civilization to avoid local disasters.
    • This indicates that alien life will attempt to do the same, and eventually, absent great filters, expand their civilization through the cosmos.
  • The Data Point – future technological advances will likely enable civilization to expand ‘explosively’ fast (relative to cosmological timescales) throughout the cosmos – however we a yet have no evidence of this happening, and if there was available evidence, we would have likely detected it by now – much of the argument for the great filter follows from this.
    • within at most the next million years (absent filters) it is foreseeable that our civilization may reach an “explosive point”; rapidly expanding outwards to utilize more and more available mass and energy resources.
    • Civilization will ‘scatter & adapt’ to expand well beyond the reach of any one large catastrophy (i.e. a supernova) to avoid total annihilation.
    • Civilization will recognisably disturb the places it colonizes, adapting the environment into ideal structures (i.e. create orbiting solar collectors, dyson spheres or matrioshka brains thereby substantially changing the star’s spectral output and appearance.  Really really advanced civs may even attempt wholesale reconstruction of galaxies)
    • But we haven’t detected an alien takeover on our planet, or seen anything in the sky to reflect expansionalist civs – even if earth or our solar system was kept in a ‘nature preserve’ (look up the “Zoo Hypothesis”) we should be able to see evidence in the sky of aggressive colonization of other star systems.  Despite great success stories in explaining how natural phenomenon in the cosmos works (mostly “dead” physical processes), we see no convincing evidence of alien life.
  • The Great Filter – ‘The Great Silence’ implies that at least one of the 9 steps to achieving an advanced expansionist civilization (outlined below) is very improbable; somewhere between dead matter and explosive growth lies The Great Filter.
    1. The right star system (including organics)
    2. Reproductive something (e.g. RNA)
    3. Simple (prokaryotic) single-cell life
    4. Complex (archaeatic & 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
  • Someone’s Story is Wrong / It Matters Who’s Wrong –  the great silence, as mentioned above seems to indicate that more or more of plausible sounding stories we have about the transitions through each of the 9 steps above is less probable than they look or just plain wrong. To the extent that the evolutionary steps to achieve our civilization were easy, our future success to achieve a technologically advanced / superintelligent / explosively expansionist civilization is highly improbable.  Realising this helps may help inform how we approach how we strategize our future.
    • Some scientists think that transitioning from prokaryotic (single-celled) life and archaeatic or eukaryotic life is rare – though it seems it has happened at least 42 times
    • Even if most of society wants to stagnate or slow down to stable speeds of expansion, it’s not infeasible that some part of our civ will escape and rapidly expand
    • Optimism about our future opposes optimisim about the ease at which life can evolve to where we are now.
    • Being aware of the Great Filter may at least help us improve our chances
  • Reconsidering Biology – Several potentially hard trial-and-error steps between dead matter and modern humans (lifecomplexitysexsocietycradle and language etc) – the harder they were, the more likely they can account for the great silence
  • Reconsidering AstroPhysics – physical phenomena which might reduce the likelihood we would see evidence of an expansionist civ
    • fast space travel may be more difficult even for superintelligence, the lower the maximum speed, the more it could account for the great silence.
    • The relative size of the universe could be smaller than we think, containing less constellations
    • There could be natural ‘baby universes’ which erupt with huge amounts of matter/energy which keep expansionist civs occupied, or effectively trapped
    • Harvesting energy on a large scale may be impossible, or the way in which it is done always preserves natural spectra
    • Advanced life may consistently colonize dark matter
  • Rethinking Social Theories – in order for advanced civs to be achieved, they must first loose ‘predispositions to territoriality and aggression’ making them ‘less likely to engage in galactic emperialism’

We can’t detect expansionist civs, and our default assumption is that there was plenty of time and hospitable space for advanced enough life to arise – especially if you agree with panspermia – that life could be seeded by precursors on roaming cosmic bodies (i.e. comets) – resulting in more life-bearing planets on them.  We can assume plausible reasons for a series of filters which slow down or halt evolutionary progress which would otherwise finally arrive at technologically savvy life capable of expansionist civs – but why all of them?

It seems like we as a technologically capable species are on the verge of having our civilizaiton escape earths gravity well and go spacefaring – so how far along the great filter are we?

Though it’s been thought to be less accurate than some of its predecessors, and more of a rallying point – let us revisit the Drake Equation anyway because its a good tool for helping understand the apparent contradiction between high probability estimates for the existence of extraterrestrial civilizations, and the complete lack of evidence that such civilizations exist.

The number of active, communicative extraterrestrial civilizations in the Milky Way galaxy N is assumed to be equal to the mathematical product of:

  1. R, the average rate of star formations, in our galaxy,
  2. fp, the fraction of formed stars that have planets,
  3. ne for stars that have planets, the average number of planets that can potentially support life,
  4. fl, the fraction of those planets that actually develop life,
  5. fi, the fraction of planets bearing life on which intelligent, civilized life, has developed,
  6. fc, the fraction of these civilizations that have developed communications, i.e., technologies that release detectable signs into space, and
  7. L, the length of time over which such civilizations release detectable signals,

 

Which of the values on the right side of the equation (1 to 7 above) are the biggest reasons (or most significant filters) for the ‘N’ value  (the estimated number of alien civilizations in our galaxy capable of communication) being so small?  if a substantial amount of the great filter is explained by ‘L’, then we are in trouble because the length of time expansionist civs emit signals likely correlates with how long they survive before disappearing (which we can assume likely means going extinct, though there are other possible explanations for going silent).  If other civs don’t seem to last long, then we can infer statistically that our civ might not either.  The larger the remaining filter we have ahead of us, the more cautious and careful we ought to be to avoid potential show stoppers.

So let’s hope that the great filter is behind us, or a substantial proportion is – meaning that the seemingly rare occurrence of expansionist civs is likely because the emergence of intelligent life is rare, rather than it being because the time expansionist civs exist is short.

The more we develop our theories about the potential behaviours of expansionist civs the more we may expand upon or adapt the ‘L’ section of the drake equation.

Many of the paramaters in the Drake Equation are really hard to quantify – exoplanet data from the Keplar Telescope has been used to adapt the Drake equation already – based on this data it seems that there seems to be far more potentially earth like habitable planets within our galaxy, which both excites me because news about alien life is exciting, and frustrates me because it decreases the odds that the larger portion of the great filter is behind us.

Only by doing the best we can with the very best that an era offers, do we find the way to do better in the future.'Frank Drake' - A Reminiscence of Project Ozma, Cosmic Search Vol. 1, No. 1, January 1979

Interview

…we should remember that the Great Filter is so very large that it is not enough to just find some improbable steps; they must be improbable enough. Even if life only evolves once per galaxy, that still leaves the problem of explaining the rest of the filter: why we haven’t seen an explosion arriving here from any other galaxies in our past universe? And if we can’t find the Great Filter in our past, we’ll have to fear it in our future.Robin Hanson - The 'Great Filter' - should we worry?

As stated on the Overcoming Bias blog:

We have three main sources of info on existential risks (xrisks):

  1. Inside View Analysis – where we try to use our best theories to reason about particular causal processes.
  2. Earth Track Records – the empirical distribution of related events observed so far on Earth.
  3. The Great Filter – inferences from the fact that the universe looks dead everywhere but here.

These sources are roughly equally informative. #2 suggests xrisks are low, even if high enough to deserve much effort to prevent them. I’d say that most variations on #1 suggest the same. However, #3 suggests xrisks could be very high, which should encourage more xrisk-mitigation efforts.

Ironically most xrisk efforts (of which I’m aware) focus on AI-risk, which can’t explain the great filter. Most analysis efforts also focus on #1, less on #2, and almost none on #3.

“What’s the worst that could happen?” – in 1996 (revised in 1998) Robin Hanson wrote:

Humanity seems to have a bright future, i.e., a non-trivial chance of expanding to fill the universe with lasting life. But the fact that space near us seems dead now tells us that any given piece of dead matter faces an astronomically low chance of begating such a future. There thus exists a great filter between death and expanding lasting life, and humanity faces the ominous question: how far along this filter are we?The Great Filter - Are We Almost Past It? - 'Robin Hanson'
If the ‘Great Filter’ is ahead of us, we could fatalistically resign ourselves to the view that human priorities too skewed to coordinate towards avoiding being ‘filtered’, or we can try to do something to decrease the odds of being filtered. To coordinate what our way around a great filter we need to have some idea of plausible filters.
How may a future great filter manifest?
– Reapers (mass effect)?
– Bezerker probes sent out to destroy any up and coming civilization that reaches a certain point? (A malevolent alien teenager in their basement could have seeded self-replicating bezerker probes as a ‘practical joke’)
– A robot takeover? (If this has been the cause of great filters in the past then why don’t we see evidence of expansionist robot civilizations? see here.  Also if the two major end states of life are either dead or genocidal intelligence explosion, and we aren’t the first, then it is speculated that we should live in a young universe.)

Robin Hanson gave a TedX talk on the Great Filter:

Bio

Robin Hanson is an associate professor of economics at George Mason University, a research associate at the Future of Humanity Institute of Oxford University, and chief scientist at Consensus Point. After receiving his Ph.D. in social science from the California Institute of Technology in 1997, Robin was a Robert Wood Johnson Foundation health policy scholar at the University of California at Berkeley. In 1984, Robin received a masters in physics and a masters in the philosophy of science from the University of Chicago, and afterward spent nine years researching artificial intelligence, Bayesian statistics, and hypertext publishing at Lockheed, NASA, and independently.

Robin has over 70 publications, and has pioneered prediction markets since 1988, being a principal architect of the first internal corporate markets, at Xanadu in 1990, of the first web markets, the Foresight Exchange since 1994, of DARPA’s Policy Analysis Market, from 2001 to 2003, and of Daggre/Scicast, since 2010.

Links

Robin Hanson’s 1998 revision on the paper he wrote on the Great Filter in 1996
– The Drake Equation at connormorency  (where I got the Drake equation image – thanks)|
Slate Star Codex – Don’t Fear the Filter
Ask Ethan: How Fast Could Life Have Arisen In The Universe?
Keith Wiley – The Fermi Paradox, Self-Replicating Probes, Interstellar Transport Bandwidth

Another Milestone in Achieving Brain Preservation & Whole Brain Emulation

A technology designed to preserve synapses across the whole brain of a large mammal is successful – covered in this interview with Keith Wiley, Fellow of the Brain Preservation Foundation.
(see below)
In an announcement from the Brain Preservation Foundation, it’s president Ken Hayworth writes:

Using a combination of ultrafast glutaraldehyde fixation and very low temperature storage, researchers have demonstrated for the first-time ever a way to preserve a brain’s connectome (the 150 trillion synaptic connections presumed to encode all of a person’s knowledge) for centuries-long storage in a large mammal. This laboratory demonstration clears the way to develop Aldehyde-Stabilized Cryopreservation into a ‘last resort’ medical option, one that would prevent the destruction of the patient’s unique connectome, offering at least some hope for future revival via mind uploading. [ref]

The neuroscience and medical communities should begin an open debate regarding ASC’s ability to preserve the information content of the brain. BPF President Ken Hayworth

The significance of the Aldehyde-Stabilized-Cryopreservation as a means to achieve future revival is hotly debated among neuroscientists, cryonicists, futurists, philosophers, and likely some concerned clergymen of various persuasions. Keith Wiley (a fellow at BPF) reached out to me to do an interview on the subject – always eager to help fan the flames, I enthusiastically accepted. I also happen to think that the topic is very important (see my previous interviews with Kennith Hayworth on the first small-mammalian preservation prize being won: ‘Verifiable Brain Preservation’, and a two part epic interview on brain preservation: see part 1 and part 2).

Interview with Keith Wiley

Discussing the Brain Preservation Foundation’s announcement of the large mammal prize and related topics.


Topics covered:

Keith Wiley

Keith Wiley

– 1000ft view: What/why research brain preservation?
– The burning of the library of Alexandria was an unfortunate loss of knowledge. How can we be so complacent about brain death?
– Where are we at? Neuroscience imaging technology is preparing to map entire insect and small mammal brains at the nanometer scale using ultrafast electron microscopes, with the near-term goal of reading memories.
– Aldehyde-Stabilized Cryopreservation: what is it? How does it work?
– Previous small-mammal brain preservation prize won in 2016 – how does large-brain one differ? Extra proof of concept? How is it emblematic of progress?
– The difference between biological and uploaded revival (because the award winning technique that made the news can’t be reversed for biological revival) – Ship of Theseus / Grandfathers Axe
– The BPF’s heavy interest in gaining scientific credibility for brain preservation through peer-reviewed publications and research, and through objective investigation of preserved brains for verification — the BPF’s lack of confidence in relying on futuristic nanotechnology to repair any damage caused by the preservation process (which cryonics folks generally rely on when told their process might be damaging the brain)

Brain Preservation Foundation: http://www.brainpreservation.org/

About the BPF: The Brain Preservation Foundation is a non-profit organization with the goal of furthering research in whole brain preservation. The BPF does not currently support the offering of ASC, or any other preservation method, to human patients. This single Prize winning laboratory demonstration is insufficient to address the types of quality control measures that should be expected of any procedure that would be applied to humans. BPF president Kenneth Hayworth has released a document outlining his position on what should be expected prior to any such offering.


About Keith Wiley: he is a fellow with the Brain Preservation Foundation and a board member with Carboncopies, which promotes research and development into whole brain emulation. He has written several articles and papers on the philosophy of mind uploading. His book, A Taxonomy and Metaphysics of Mind-Uploading, is available on Amazon. Keith’s website is http://keithwiley.com.

A link to the associated text chatroom discussion (which seems to disappear after the live event ends) is here.

The Debate Rages On!

The BPF prize kindles debates around the world on

  • which brain preservation techniques actually work, and how do we verify this?
  • what are the best roadmaps to achieve viable brain preservation in view to achieve individual survival beyond our current understanding of biological death?
  • and ultimately, if ‘technological resurrection’ were possible, should we allow it?

All very healthy debates to be having!

See PrWeb’s article
Aldehyde-Stabilized Cryopreservation Wins Final Phase of Brain Preservation Prize
.

The significance of this Prize win is sure to be debated. Those who dismiss the possibility of future mind uploading will likely view ASC as simply the high-quality embalming and cold storage of a deceased body—an utter waste of time and resources. On the other hand, those who expect that humanity will eventually develop mind uploading technology are more likely to view ASC as perhaps their best chance to survive and reach that future world. It may take decades or even centuries to develop the technology to upload minds if it is even possible at all. ASC would enable patients to safely wait out those centuries. For now, neuroscience is actively exploring the plausibility of mind uploading through ongoing studies of the physical basis of memory, and through development of large-scale neural simulations and tools to map connectomes. This Prize win should shine a spotlight on such neuroscience research, underscoring its importance to humanity.

I point this out because adoption of pattern versus continuity views of identity should determine an individual’s view of the utility of vitrifixation for brain preservation. The primary point to consider here is that chemical fixation is a good deal less reversible than present day vitrification, low temperature storage with cryoprotectants. The reversible vitrification of organs is a near-future goal for a number of research groups. But reversing chemical fixation would require advanced molecular nanotechnology at the very least – it is in principle possible, but far, far distant in our science fiction future. The people advocating vitrifixation are generally of the pattern identity persuasion: they want, as soon as possible, a reliable, highest quality means of preserving the data of the mind. It doesn’t matter to them that it is effectively irreversible, as they aren’t hoping to use the brain again after the fact. ASHBURN, Va. (PRWEB) March 13, 2018

Fight Ageing’s alternative view on preservation of pattern and continuity is summarized here here

For those of us who adhere to the alternative viewpoint, the continuity theory of identity, the self is the combination of the pattern and its implementation in a specific set of matter: it is this mind as encoded in this brain. A copy is a copy, a new entity, not the self. Discarding the stored brain is death. The goal in the continuity theory view is to use some combination of future biotechnology and nanotechnology to reverse the storage methodology, repair any damage accumulated in the brain, and house it in a new body, restoring that individual to life.

I point this out because adoption of pattern versus continuity views of identity should determine an individual’s view of the utility of vitrifixation for brain preservation. The primary point to consider here is that chemical fixation is a good deal less reversible than present day vitrification, low temperature storage with cryoprotectants. The reversible vitrification of organs is a near-future goal for a number of research groups. But reversing chemical fixation would require advanced molecular nanotechnology at the very least – it is in principle possible, but far, far distant in our science fiction future. The people advocating vitrifixation are generally of the pattern identity persuasion: they want, as soon as possible, a reliable, highest quality means of preserving the data of the mind. It doesn’t matter to them that it is effectively irreversible, as they aren’t hoping to use the brain again after the fact. Fight Ageing -

Also see the Alcor Position Statement on Brain Preservation Foundation Prize.

While ASC produces clearer images than current methods of vitrification without fixation, it does so at the expense of being toxic to the biological machinery of life by wreaking havoc on a molecular scale. Chemical fixation results in chemical changes (the same as embalming) that are extreme and difficult to evaluate in the absence of at least residual viability. Certainly, fixation is likely to be much harder to reverse so as to restore biological viability as compared to vitrification without fixation. Fixation is also known to increase freezing damage if cryoprotectant penetration is inadequate, further adding to the risk of using fixation under non-ideal conditions that are common in cryonics. Another reason for lack of interest in pursuing this approach is that it is a research dead end on the road to developing reversible tissue preservation in the nearer future.

I point this out because adoption of pattern versus continuity views of identity should determine an individual’s view of the utility of vitrifixation for brain preservation. The primary point to consider here is that chemical fixation is a good deal less reversible than present day vitrification, low temperature storage with cryoprotectants. The reversible vitrification of organs is a near-future goal for a number of research groups. But reversing chemical fixation would require advanced molecular nanotechnology at the very least – it is in principle possible, but far, far distant in our science fiction future. The people advocating vitrifixation are generally of the pattern identity persuasion: they want, as soon as possible, a reliable, highest quality means of preserving the data of the mind. It doesn’t matter to them that it is effectively irreversible, as they aren’t hoping to use the brain again after the fact. Alcor President, Max More

 

No doubt these issues will inspire heated discussion, and challenge some of the core assumptions of what it means to be human, to have a thinking & self-aware mind, to be alive, and to die. Though some cherished beliefs may be bruised in the process, I believe humanity will be better for it – especially if brain preservation technologies actually do work in .

Medical time-travel for the win!


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