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    Are We Alone In The Cosmos, Cursed By Fermi's Paradox?
    By David Brin | November 25th 2012 06:19 PM | 24 comments | Print | E-mail | Track Comments
    About David

    David Brin is a scientist, public speaker, technical consultant and author of books including The Postman, Startide Rising, The Uplift War and Existence...

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    And now the news from Alpha Centauri(Oh, I’ve waited for so long to utter those words! News. From Alpha Centauri. Wow!)


    DB-radiotelescopeAfter an incredible decade, in which the number of planets known beyond our solar system increased from zero to several hundred, with a couple of thousand potential "hits" still to verify, astronomers have now detected a roughly Earth-sized world orbiting between the two stars nearest to our system, Alpha Centauri A and Alpha Centauri B.  Much too hot to sustain life, it nevertheless will help in narrowing down the search space for others.  Moreover, now we have a target for the first interstellar probes, which are already under discussion.  Indeed, the youngest of you readers may live to see them launched.


    Ah, but this raises the perennial question.  If planets are more common than we ever thought, then what about life-worlds? And even alien intelligences?


    I have been involved in this topic all my life, having grown up in Southern California, the part of human civilization least rooted in the familiar, traditional or... perhaps... sane.  I am best-known today as an author of novels and stories about our many possible-plausible futures, including some that explore a wide range of possible extraterrestrial civilizations. My scientific career, ranging from optics to astrophysics, led to papers about SETI in the 1980s that include what is still the only full review article in the field, compiling all then public theories for what I called The Great Silence, but that is now more widely known as the Fermi Paradox. (See a collection of articles and speculations about the Search for Extraterrestrial Intelligence (SETI).)


    Today, we'll dive into the Fermi Paradox, in some detail. But first a little background.

    070109-pulsar-nebula_big


    The first time I witnessed the subject of extraterrestrial intelligence brought up in a scientific setting was at a Caltech physics colloquium in 1968, when I was just seventeen. The speaker remarked on the remote possibility that pulsars -- recently discovered radio sources that emitted bursts in perfect rhythm -- might turn out to be beacons of an advanced civilization. They were, after all, several thousand times more regular in their repetitive "beepings" than any other astronomical radio source ever discovered.


    The speaker was only partly serious, though pulsars to this day are listed in catalogues with the prefix LGM -- a smiling reference to "Little Green Man." Despite that whimsy,  sides were quickly taken, and it was soon very clear that most of those with tenure didn't like this kind of talk at all.


    But attitudes were changing rapidly during that decade -- the exciting era of Apollo moon landings and stunning pop music. A few years later some of those who seemed angriest in 1968 applauded loudly when Carl Sagan unveiled the gold plaque that was to be placed upon Pioneer 10, the first human artifact launched on a trajectory that would take it out of the solar system.

    Pioneer10-plaque


    Today that plaque is famous, along with "messages" that followed on Pioneer 11 and the Voyager probes. They depict the nude figures of a woman and a man, an arm raised in greeting, a schematic of the planets of our system, and a rayed pattern of lines and binary dots representing the most prominent pulsars detectable from Earth. The pulsar map should enable any distant beings who recover the spacecraft to trace its point of origin within a light-year in space, and its launch date to within six months.  Oh, and the Voyager probes famously carry disks with recorded sounds and images of Earth. In fact, no scientist expects the messages to be recovered by aliens, though our own speedy descendants may collect Voyager for a museum.


    Ever since the 1960s another, related project went through many ups and downs.  SETI programs (Search for Extraterrestrial Intelligence) prospered and withered under public excitement and ridicule, a cycle that continues even today... and that we may discuss another time. But let's stay focused.


    2001aspaceodysseyOf course other-worlds and their inhabitants had already long been the topic of stories -- some great and others dismal -- on the pages of science fiction pulps of the thirties and forties, then more insightful thought experiments by Arthur C. Clarke, Ray Bradbury Robert Heinlein and others.  A tradition that extends through authors like C.J. Cherryh, Greg Bear and Dan Simmons all the way to more recent speculations about alien thought processes by Ken MacLeod and Iain Banks.


    In fact, this tradition goes back much farther, to wanderers' tales like Journey to the West and the Odyssey. The expansion of our horizons of interest may be among the most human of all activities, as we stretch our gaze and curiosity beyond the mere present, the mere town, nation or even planet.  If we ever do encounter the alien, 

    ExpansionHOrizons

    it can be hoped that the vast literature of science fiction gedankenexperiments (thought experiments) about contact will be consulted by our wisest sages -- who may be enlightened by the vast range of possibilities we humans have already imagined.


    == The Essential Questions About Alien Life ==


    The Fermi Paradox refers to a question posed by the great physicist Enrico Fermi in the 1940s, demanding: "If it seems so likely the universe may host other life forms, how come we haven't seen any signs?"  Not just of radio beacons, but of mighty structures that our own descendants might someday build out there in space. Or leakage from chatty commerce between civilizations.  Or indeed, any trace that the Earth was visited during the 2 billion years that it was "prime real estate" with an oxygen atmosphere, but nothing higher than slime molds to defend it.


    It is a fascinating topic... perhaps the fascinating topic.  For it takes you from pondering the birth and death of stars and planets to the dynamics of atmospheres and the potential origins or life... to intelligence (what is it and how many varieties can it come in?)... all the way to the stark possibility that few technological species survive their tense adolescence, attempting to cross a minefield of potentially lethal errors, from nuclear war or designer plagues to ecological devastation or cultural stagnation.


    == The Drake Equation ==


    The most common tool that folks use, in appraising the Great Silence is a little gem called the Drake Equation (D.E.), concocted by the early SETI pioneer Frank Drake when he was at the Arecibo National Radio Observatory. It remains the most widely accepted tool for xenological speculation.


    DrakeEquationLet N = the current number of technological civilizations in the galaxy. Then,


    N = R P n(e) f(1) f(i) f(c) L


    Here R is the average rate of production of suitable stars since the formation of the galaxy, approximately one per year. (The current rate is slower. R is an average that includes the burst of star creation early in the galaxy's history.)  f(s) is the fraction of stars that are accompanied by stably orbiting planets. Factor n(e) is the average number of planets per system that have the requisite conditions to support life.


    The other factors include f(1), the fraction of these congenial planets on which life actually occurs; f(i), the fraction of these on which "intelligence" appears; f(c), the fraction of intelligent species that attain technological civilizations, and L, the average lifespan of each species.


    The Drake Equation certainly seems to line up the varied factors involved in bringing sapient life to prominence in our galaxy.  All the terms on the far left of the D.E. have to do with the prevalence of stable, reliable stars... and then how many have planets. There are plenty of stable, long-lived G-type dwarf stars like the Sun out there... about 6 percent of the galaxy's several hundred billion stars. Are there planets circling many of them? (We astronomers were always sure there were, for reasons of angular momentum that I won't go into here. We've grown a lot more confident in recent years! Though mysteries still abound.)


    == The likelihood of life ==


    What are the chances of life erupting spontaneously on isolated worlds? It appeared to do so swiftly on Earth, almost as soon as the planet cooled enough for oceans to form. Three scientific discoveries and one useful philosophical tool gave researchers the courage to make crude estimates about the distribution of life among the stars.


    Miller-UreyThe first discovery came when it was found almost ridiculously easy to make amino acids, and other precursors to living matter, from abundant molecules such as methane, ammonia and cyanogen. Stanley Miller subjected a water solution of these substances to electrical discharge and ultraviolet radiation and got an organic "soup" in short order. Leslie Orgel of the Salk Institute accomplished the same thing by a freezing process. The high pressures of ice formation not only gave up amino acids, but the purine adenine as well. (Adenine is one of the four building blocks of DNA, and is the core of ATP, adenosine tri-phosphate, which controls the energy economy of the living cell.


    So many mechanisms have been found that can change crude precursors into "biological" molecules that today organic activity seems almost an automatic consequence of the distribution of chemical elements in the universe.


    The second major discovery supports this point of view. During the last two decades, radio astronomers -- listening to narrow emission lines from interstellar space -- have discovered great clouds of complex molecules: ethylene, formaldehyde, ethyl alcohol; some even claim evidence for -- you guessed it -- adenine. (Astronomer and science fiction author Sir Fred Hoyle, looking at starlight scattered from interstellar dust, even thought that the dust itself might actually be something akin to bacteria... living cells about a micron in size, in diffuse colonies spanning light-years and outmassing suns. It's an extravagant speculation, but fun to think about.)


    It's clear, then, from basic chemistry and radio astronomy, that the basic materials for life are out there. What about the right environments? We have to assume, until we have reason to think otherwise, that complex life must grow and evolve to intelligence on planets orbiting stable stars. Are there other "nursery worlds" like the Earth? Or might ecosystems more likely be found under the ice coverings of "roofed worlds" like Europa and Enceledus, where life-giving heat rises from below and any denizens would never see the stars?


    == The Role of Sapience ==


    Assuming planets are common and life is not rare, then how do we explain the Fermi Paradox?  Well, some hold that the factor that's small -- that keeps the numbers down --if f(l), the likelihood that a planet will create an intelligent species.  After all, it appears to have happened just once in 4.5 billion years on Earth... though some question whether it has happened yet, on this planet, at all!


    What about dolphins, apes, sea lions, crows, parrots... even prairie dogs and octopus, who now show signs of some linguistic ability and problem solving savvy?  They all seem to crowd under a "glass ceiling" that none has ever broken through (except us).  Could that represent some kind of law of nature, and might we be a fluke?


    A separate question, that I explore in EXISTENCE and also in my Uplift Series of novels is whether we should start to help other species burst through that glass ceiling and join us, as fully sapient fellow citizens of a much broader and more diverse Earthly culture.  The end result, that I portray in Startide Rising and The Uplift War, is a much richer and wiser civilization.


    But oh, the pain of the two centuries it might take, to get there.  Are we willing – and sure enough of our skill and compassion – to embark on such a journey? Would it be the height of hubris and arrogance? Or would it be the ultimate act of selfishness to reject this challenge? To say to such species “we made it to the level of art and literature and ideas and science… and we refuse to offer anybody else a hand!”


    == The Minefield Ahead of Us ==


    images-1All of the factors in the Drake Equation that we've discussed so far are ones that might explain the Fermi Paradox by keeping down the numbers of intelligent beings who reach our level.  If any of those factors were responsible for the Great Silence, then that means the Big Filter lies behind us.  We are rare... but the galaxy lies open before us and nothing stands in our way!


    Then come the grouches who insist that life and intelligence and good planets and all that must be abundant, but that the Filter lies ahead of us.  Remember the minefield of possible mistakes that a “smart” race might make, from nuclear war to eco-devastation?  With that long litany of potential failure modes in mind, these folks ask how long any technological species can survive that endless expanse of snake pits, quicksand and possible ways to commit suicide. All of which falls into the Drake Equation factor “L” or how long such a species can survive.


    (As it turns out, Drake left out several possible factors, but I'll leave it as an exercise for the fanatics among you to read my astrophysical article about this.)


    Suffice it to say that these two sides -- those who think the Filter lies behind us and those who cry "look out!" -- are in furious debate to this day.  And it may surprise you that the "grouches" include many in the SETI community, those looking the hardest with radio telescopes, who openly admit that they are searching for the exceptions who do not kill themselves.


    Again, there is no topic like this one, so rife with mind-blowing possibilities... and so free of any data about actual alien life! And yet so prone to sudden, premature conclusions, in which smart people declare "I know the answer!" without a shred of supporting evidence.


    And why not?  This is, after all, the greatest Rorsach Test... a mirror or ink blot on which we project our personalities and notions and worries about our own species... our own selves. (And if so, what does it say about me, that I am one of the few saying "wait! We don't know enough yet. Don't jettison any of the possibilities too soon. The universe may yet surprise us.)


    Here are a few other links for those who relish our most precious human gift.  The wonder of curiosity.  The insatiable thirst to know about what we know... and to speculate about what we don't and to explore this vast realm. A topic we all find fascinating... and as-yet we understand so poorly.





    Comments

    Michael Martinez
    You don't need the Drake Equation or all these speculations to explain the Fermi Paradox, which is not a paradox but just a Magic Assumption.  If intelligent life exists elsewhere in the universe, why is it supposed to land on Earth?  Why is it supposed to send us a sign that it exists?  The Magic Assumption is that any intelligent life out there will know about us, care about us, want to communicate with us, and should have made the effort by now.
    That's a very big, complicated Magic Assumption.  Fermi should be forgiven for posing it.  I find it much harder to forgive the scientific community for continuing to repeat this nonsense after so many decades.
    In point of fact, you don't seem to properly understand the argument that relatively-high frequency life proponents are making, which relates to growth speeds. Make the assumption that the occurrence of life is unusual, but not insanely so. The first stars formed within a billion years of the Big Bang - but they were third population, metal-poor stars. Second population and first population stars took another billion years. At the end of 2 gigayears, you have planets vaguely Earth-like, perhaps enough like to house our kinds of life. Assume we're kinda quick, and it takes 6 GY normally for intelligent life to arise. We're at 8 GY after the Big Bang. This *one* planet in a galaxy starts sending out slowboats - generation ships travelling at 1/1000th C to the next star. Lands, colonizes, eventually starts sending out its own generation ships. How fast to fill up the galaxy they're in? *MAYBE* as much as half a billion years. That leaves us at T+8.5 GY post Big Bang, and *EVERY* planet in the galaxy is occupied. It's 5 gigayears later - where the heck *IS* everyone???

    And that's using what many people feel are severely un-realistic assumptions about the rate of planetary formation, life occurrence, and intelligent life growth. The only realistic presumption is that something cuts off the life span of intelligent races, or otherwise prevents them from reaching us, be it converting a planet into computronium, nuking themselves back to the stone age repeatedly, or mysterious crystal spheres around life-friendly stars preventing races from taking them over (and notice Dr. Brin *still* presumed humans were the 5th or 6th race to arise!)

    Gerhard Adam
    The only realistic presumption is that something cuts off the life span of intelligent races, or otherwise prevents them from reaching us...
    Actually there are several serious flaws already.  One, the concept of intelligence, in this context, is woefully abused and doesn't mean what people think it does.  Human trips into space have little or nothing to do with individual innate human intelligence.  It is a direct result of human social organization.  There is no single human that could venture into space, not ever.  Therefore, intelligence is insufficient to the task of traveling into space or populating other planets. 

    Moreover, intelligence exists in numerous species, so it isn't intelligence, per se, but rather a specific type of intelligence which is obviously rare given the millions of species that exist and have ever existed, from which only one approaches the requisite level.

    I find the concept of planetary colonization quaintly naive, since it requires transporting an entire ecosystem and not merely a few individuals.  In virtually every discussion I've heard regarding human colonization, it's more in line with a Disney view of the "natural world" than anything realistic.   Any planet capable of supporting life [on which life was actually present] would be the most dangerous place to visit.   To colonize it would require destroying it.  

    There's nothing surprising about the Fermi Paradox.  What disturbs most people in such discussions is that the unspoken element that it hints at, in that there may be limits to what is achievable and understandable.  In other words, it suggests that our hubris regarding what humans will be capable of achieving has limits.  We will not become Masters of the Universe.
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Any planet capable of supporting life [on which life was actually present] would be the most dangerous place to visit.   To colonize it would require destroying it. 
    Well, it would not be necessary to destroy it Gerhard, better to genetically modify the planet I would have thought? Say for example there was a planet where all of the life forms were either insect like or plant like both of which were toxic to us humans and animals on Earth, along with probably the climate.

    Rather than destroying the plants and insects or trying to modify the climate we could genetically modify one or other of them to be nutritious for us or genetically modify ourselves to find them nutritious or alternatively we could genetically modify the existing insects with our genes to become more human, you know, to be intelligent and special like us! So we and our human genes would continue to evolve but just in a new life form and environment. Maybe aliens have already genetically modified themselves on to other planets like this? If humans managed to do this too then it would be a bit like an action replay of how Earth's different empires historically grew then explored and then colonised the rest of the World.
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    Sorry, but that would be destroying it.  Since you would literally have to modify millions of organisms, then what is left? 

    Nutrition isn't much of a factor when you consider that one human being would suddenly introduce about 100 trillion microbes to an environment from which they didn't originate.  How long do you think it would be before one or the other destroys the other?

    For those that wish to argue that an alternate biology wouldn't necessarily be capable of interacting and consequently wouldn't be toxic, ... well that is precisely the point isn't it.  If the biology is incapable of interacting, then none of it is useful to sustain ourselves, so why would we allow biological competitors for resources to exist?

    There's simply no compromise.  Again, we've already seen how well non-useful species have fared on earth. 
    Mundus vult decipi
    Michael Martinez
    It has long seemed to me that the most efficient answers are to either find lifeless planets that could support our ecology (and problems would ensue over "generations" as those planets became isolated from the "mainstream") or to construct self-sustaining habitats capable of moving through interstellar space.
    Permanent self-sustaining habitations would allow us to move through space and absorb raw materials from random star systems.  They would not have to move any faster than necessary to get to the next supply of raw materials.

    At least with self-sustaining habitats we wouldn't have to worry too much about adapting to the ecology of any life-bearing planets we encounter; we could "stand off" and be UFOs to some other civilization (sorry -- couldn't resist injecting the irony).

    Our descendants could make a sort of "Grand Tour" of the galaxy and maybe eventually the universe -- and they would not have to worry about how many life-sustaining worlds the universe is capable of producing.  They would make their own worlds.
    Gerhard Adam
    At least with self-sustaining habitats we wouldn't have to worry too much about adapting to the ecology of any life-bearing planets we encounter...
    Actually we'd have quite a lot to worry about, because we aren't in control.  Everything will depend on the behavior and reaction to the trillions of microbes that accompany us, and present evidence suggests that bacteria do not like traveling in space.  Increases in virulence and the rapidity with which they can change [especially in small closed ecosystems] suggests that our requirements aren't the problem that needs to be solved.

    Mundus vult decipi
    Michael Martinez
    I wasn't suggesting SMALL ("closed") ecosystems.  I was suggesting self-sustaining habitats, which would have to solve the many problems that spaceships cannot.  The Earth supports a mostly closed ecosystem.  That ecosystem was once smaller than it is today (and simpler).  It's too soon to write off the possibility just because we haven't yet figured out how to do it.
    Gerhard Adam
    While I don't know specifically what you had in mind, my point is that even if we built a self-sustaining habitat that could accommodate a million people, assorted animals/plants for food, ecological environments, etc. it would still be quite small compared to planet Earth.

    Therefore, it would effectively involve constructing the equivalent of artificial planets.  So on the one hand it would be an immense work of engineering to make something like that capable of traveling, but also it would be biologically tiny in terms of the evolutionary forces that would still be at work. 
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Yes but we haven't started genetically modifying ourselves to fit in with any new environments yet, can you imagine what fun that would be? Humans with wings or gills or shells or heat resistant or solar powered or whatever we need to fit in to a new environment. Surely that has to be the way we would colonise new hostile environments, now we have the technology. I guess that all that would really be evolving is new human intelligent like life forms versus alien intelligent like life forms. Maybe intelligence is compelled to genetically evolve as soon as it has the ability to genetically modify life and itself regardless of whether it is human or alien in origin. What would that even matter really, as long as they and we agreed on an evolving intelligence code of ethics to suit the new environments and/or planet? OK humans now with an average IQ of 100 couldn't do it but they would be a thing of the past :)
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Bonny Bonobo alias Brat
    Sorry, but that would be destroying it.  Since you would literally have to modify millions of organisms, then what is left? 
    Please reread my comment Gerhard you obviously haven't understood what I was saying.
    Nutrition isn't much of a factor when you consider that one human being would suddenly introduce about 100 trillion microbes to an environment from which they didn't originate.  How long do you think it would be before one or the other destroys the other?
    That was only one option, making the plants nutritious, the least likely as the climate is toxic to humans so there is no point in ontroducing humans there at all.
    For those that wish to argue that an alternate biology wouldn't necessarily be capable of interacting and consequently wouldn't be toxic, ... well that is precisely the point isn't it.  If the biology is incapable of interacting, then none of it is useful to sustain ourselves, so why would we allow biological competitors for resources to exist?
    There's simply no compromise.  Again, we've already seen how well non-useful species have fared on earth.
    That was the old human with an average IQ of 100, if intelligence genetically modifies and evolves itself then surely so will an appropriate intelligent code of ethics for this new GM intergalactic family?
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    That was the old human with an average IQ of 100, if intelligence genetically modifies and evolves itself then surely so will an appropriate intelligent code of ethics for this new GM intergalactic family?
    I'm not sure I accept the notion that greater intelligence promotes a higher ethical sense or anything else.  It seems that the greater the intellectual gap is between ourselves and some animal, the worse we tend to treat the animal involved.  Those that fare better are those displaying their own higher levels of intelligence.
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Well I doubt if lower intelligence is likely to promote a higher code of ethics either. I was eating my breakfast just now, while being keenly watched by my three dogs Tess, Zack and Sascha. They are like stalkers monitoring my every move, through every window of my house. All they are really doing though is watching out for me to put on the clothes and footwear that mean I'm about to take them for an outing or walk. The moment I do, they jump around with delight and run to my car and wait for me there. 

    Even though they are not very intelligent compared to humans, they do seem to have a strong sense of fairness and if I only take one or two dogs with me for whatever reason, those left behind are visibly very upset. Also, on the rare occasion that I don't take them out one day because of heavy rains or floods for example, they all become noticeably depressed and even seem to sulk, giving me recriminating looks. 

    Even if they have a sense of fairness, their lower than human intelligence means that they could never develop a communicable code of ethics, that could be used by our potential intergalactic GM family. However, if we were to genetically modify dogs to have much larger brains and a correspondingly much higher 'intelligence' that would be very interesting wouldn't it, to see how different their code of ethics and 'intelligence' would be compared to humans? The same of course could apply to all animals, if we could genetically modify them to have much larger brains and corresponding 'intelligence' and then compare their code of ethics and their intelligence with ours and other species. I can't help wondering why we aren't already doing this or maybe we are somewhere in the world right now and would it be ethically incorrect to do this?

    If so, then who is deciding that it is ethically OK to genetically modify our food to say contain Bacillus thuringiensis (or Bt) which is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide, in every mouthful we eat of Bt genetically modified foods such as potatoes, corn, peanuts and soya  beans but that its not ethically OK to increase the intelligence of the many dumb animals in our Earth family? An Earth family whose members we are often either exploiting or eradicating because they don't have high enough intelligence to either defend themselves or to prevent the ultimate ethical crime of their irreversible genetic extinction? Hundreds of species go extinct every day on this planet.
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    The rules of behavior don't really require higher intelligence nor ethics [consider ants/bees].  Instead we find that higher orders of intelligence don't necessarily improve behavior as much as give rise to the ability to deceive.  This is one of the reason why I point to deception as being a determining criteria in whether an AI has been created.
    Mundus vult decipi
    Bonny Bonobo alias Brat
    This is one of the reason why I point to deception as being a determining criteria in whether an AI has been created.
    Based on a rather limited sample maybe? Therefore hardly very scientific.
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    It's not based on samples, it's a definition.
    Mundus vult decipi
    Bonny Bonobo alias Brat
    What exactly is this definition then? Are you saying that a necessary proof of artificial intelligence (AI) is the AI's ability to deceive and that if it can't deceive then its not artificially intelligent?
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    Yes.  It's my definition that a conditional proof of intelligence is the ability to deceive, since it involves knowing what's true/accurate while deliberately creating an alternative representation that must be plausible and believable.  Therefore it involves holding two contradictory, yet real ideas/representations at the same time. 

    In my view, that is a necessary condition and consequence of possessing the ability to abstract.  In other words, the ability to use one's imagination and make something up.

    Mundus vult decipi
    Bonny Bonobo alias Brat
    a conditional proof of intelligence is the ability to deceive, since it involves knowing what's true/accurate while deliberately creating an alternative representation that must be plausible and believable
    Not sure why you think that's a proof of intelligence, I can easily program a computer to deceive, so what?
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Gerhard Adam
    Programming involves YOU setting the deception.  If a computer were to be considered "intelligent" it would have to be capable of doing so of its own volition.

    You already know that mere programming isn't any criteria for "intelligence".
    Mundus vult decipi
    Bonny Bonobo alias Brat
    AI has to be programmed by something, even we are programmed by our DNA, so I don't see why the ability to deceive is an important criteria for defining intelligence. Anyway, let's drop it as we're going off topic, this blog is about the likelihood of extra terrestrial (ET) alien intelligence existing somewhere out there and Fermi's paradox. It doesn't really matter how ETs or even AIs if they exist have been programmed or whether they are capable of deceiving does it? Unless they are out there and deceiving us somehow into believing  that they are not out there :)
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine
    Michael Martinez
    In point of fact, you don't seem to understand that the Fermi Paradox is neither paradoxical nor useful in a discussion like this.
    Assumptions that don't match the known facts (which are equivalent to a paint speck on a 99% blank canvas) don't mean that assumptions based on assumptions are correct, reliable, or worth noting.

    Let's assume that only 1 planet in every galaxy will ever spawn life and that only 1 in 1 million life-spawning planets will ever figure out a way to send life out to the stars.  That leaves us with absolutely no explanations of anything -- just assumptions.

    NASA scientists occasionally say really stupid things like, "If the space aliens are here, why aren't they landing on the White House lawn?"

    They never bother to explain why aliens should KNOW to land on the White House lawn, much less how the aliens are going to explain themselves once the Secret Service starts firing stinger missiles at them -- and that is after the Air Force scrambles jets to intercept them (which, according to various UFO books, has supposedly happened).

    So let's dispense with the unrealistic assumptions and admit that we're not ready to explain why we who are still glued to this rock haven't communally encountered advanced intelligences from other planets.  If they exist they're not obligated to make the Fermi Paradox work, much less to land here at all.

    Rather than being Columbus, they might be Picard, dedicated to a Prime Directive of Non-interference.  Or maybe they are just more concerned with whatever it is that advanced intelligences do than with dropping by to say "Hello" to us.
    And you've perhaps watched too much hollywood. Scientists don't discuss aliens landing at the White House - they're asking why *WE* even got a chance to evolve. Dr. Brin's astrophysical article, linked above, discusses nicely various factors the Drake Equation more or less lumps in together in some of the terms. The whole exploration of the Drake Equation is not a matter of what we know or don't know, it's a matter of examining what we don't know that we don't know, vs. what we do know that we don't know.

    Michael Martinez
    "And you've perhaps watched too much hollywood. Scientists don't discuss aliens landing at the White House" -- Sorry, but that's just not true.  There are a couple of old NASA q-and-a pages where the scientists -- answering questions from people around the country -- make glib remarks exactly like that.
    The Drake Equation made a nice coffee table discussion in the 1960s.  It's somewhat dated but still gives us a place to start wondering.  The Fermi Paradox, however, has no place in a serious discussion.



    ON EDIT: I documented NASA's terrible track record with statements about space aliens to the citizenry in this article in 2008.  I cannot promise that all the links still lead anywhere but you may be able to find the old NASA pages on Archive.Org.