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‘Mass Effect’ Solves The Fermi Paradox?

The views expressed are those of the author and are not necessarily those of Scientific American.

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Who's been munching my galaxy?

Right now, all across the planet, millions of people are engaged in a struggle with enormous implications for the very nature of life itself. Making sophisticated tactical decisions and wrestling with chilling and complex moral puzzles, they are quite literally deciding the fate of our existence.

Or at least they are pretending to.

The video game Mass Effect has now reached its third and final installment; a huge planet-destroying, species-wrecking, epic finale to a story that takes humanity from its tentative steps into interstellar space to a critical role in a galactic, and even intergalactic saga. It’s awfully good, even without all the fantastic visual design or gameplay, at the heart is a rip-roaring plot and countless backstories that tie the experience into one of the most carefully and completely imagined sci-fi universes out there.

As a scientist, and someone who will sheepishly admit to a love of videogames (from countless hours spent as a teenager coding my own rather inferior efforts, to an occasional consumer’s dip into the lushness of what a multi-billion dollar industry can produce), the Mass Effect series is fascinating for a number of reasons. The first of which is the relentless attention to plausible background detail. Take for example the task of finding mineral resources in Mass Effect 2. Flying your ship to different star systems presents you with a bird’s eye view of the planets, each of which has a fleshed out description – be it inhabited, or more often, uninhabitable. These have been torn from the annals of the real exoplanets, gussied up a little, but still recognizable. There are hot Jupiters, and icy Neptune-like worlds. There are gassy planets, rocky planets, and watery planets of great diversity in age, history and elemental composition. It’s a surprisingly good representation of what we now think is really out there.

Galactic spread of life...maybe. (Taken from J. Schombert, U. Oregon)

But the biggest idea, the biggest piece of fiction-meets-genuine-scientific-hypothesis is the overarching story of Mass Effect. It directly addresses one of the great questions of astrobiology – is there intelligent life elsewhere in our galaxy, and if so, why haven’t we intersected with it yet? The first serious thinking about this problem seems to have arisen during a lunchtime chat in the 1940′s where the famous physicist Enrico Fermi (for whom the fundamental particle type ‘fermion’ is named) is supposed to have asked “Where is Everybody?” The essence of the Fermi Paradox is that since our galaxy is very old, perhaps 10 billion years old, unless intelligent life is almost impossibly rare it will have arisen ages before we came along. Such life will have had time to essentially span the Milky Way, even if spreading out at relatively slow sub-light speeds, it – or its artificial surrogates, machines – will have reached every nook and cranny. Thus we should have noticed it, or been noticed by it, unless we are truly the only example of intelligent life.

The Fermi Paradox comes with a ton of caveats and variants. It’s not hard to think of all manner of reasons why intelligent life might be teeming out there, but still not have met us – from self-destructive behavior to the realistic hurdles of interstellar travel. But to my mind Mass Effect has what is perhaps one of the most interesting, if not entertaining, solutions. This will spoil the story; you have been warned.

Without going into all the colorful details, the central premise is that a hugely advanced and ancient race of artificially intelligent machines ‘harvests’ all sentient, space-faring life in the Milky Way every 50,000 years. These machines otherwise lie dormant out in the depths of intergalactic space. They have constructed and positioned an ingenious web of technological devices (including the Mass Effect relays, providing rapid interstellar travel) and habitats within the Galaxy that effectively sieve through the rising civilizations, helping the successful flourish and multiply, ripening them up for eventual culling. The reason for this? Well, the plot is complex and somewhat ambiguous, but one thing that these machines do is use the genetic slurry of millions, billions of individuals from a species to create new versions of themselves.

It’s a grand ol’ piece of sci-fi opera, but it also provides a neat solution to the Fermi Paradox via a number of ideas: a) The most truly advanced interstellar species spends most of its time out of the Galaxy in hibernation. b) Purging all other sentient (space-faring) life every 50,000 years puts a stop to any great spreading across the Galaxy. c) Sentient, space-faring species are inevitably drawn into the technological lures and habitats left for them, and so are less inclined to explore.

These make it very unlikely that until a species is capable of at least proper interplanetary space travel (in the game humans have to reach Mars to become aware of what’s going on at all) it will have to conclude that the Galaxy is a lonely place.

Now, I’d hesitate at placing odds on whether this specific scenario is actually the likeliest solution to Fermi’s “Where is Everybody?”  The mere fact that it’s an invention in a game we play would make it the most supreme irony if this turned out to be true. Nonetheless, the idea does hit on a few themes that are perhaps not crazy. One is that a galaxy full of intelligent, technological species may not be hospitable, a fact that could severely limit or ‘localize’ the spread of anyone (check out an earlier post on “Bad Aliens, Meme Armor, and Intelligence in the Universe“). Another is that there might be phenomena that switch on every so often and either purge life from large areas of the Galaxy, or make interstellar travel impossible. These need not be artificial. For example, we live with a four-million solar-mass black hole at the center of the Milky Way that shows evidence for episodic outbursts of energy as it accretes matter. A moderately large outburst probably happened 300 years ago, a really big outburst may have happened 25,000 to 50,000 years ago – blowing vast ‘bubbles’ of energetic particles into space. Could such events have a deleterious effect on space-faring species? Perhaps.

Better be careful...

And of course it could be that the reason we haven’t noticed the galactic hustle and bustle going on around us is indeed because we haven’t stuck our heads far up enough from our parochial planetary burrow. Who knows what will happen when we eventually do.



Caleb A. Scharf About the Author: Caleb Scharf is the director of Columbia University's multidisciplinary Astrobiology Center. He has worked in the fields of observational cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.) Follow on Twitter @caleb_scharf.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. MadScientist72 3:19 pm 03/15/2012

    There’s also the Erich von Daniken answer – We have encountered sentient extraterrestrial beings, and called them gods.
    Or the L. Ron Hubbard Scientology answer – We were put here by the extraterrestrial beings.

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  2. 2. geojellyroll 3:22 pm 03/15/2012

    Any game is ‘Garbage in and Garbage out’. There are so many variable to decide upon and almost infinite ways to weight each variable.

    just a note…it’s unfortunate Fermi ever made a comment. Talk of potential contact gets hijacked by this silly formula that is silly because it is based on silliness.

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  3. 3. deven8703 4:23 pm 03/15/2012

    I think it is much more likely that said alien beings, in their version of a galactic UN, have declared Earth and its solar system a protected zone. Much as some of us humans hate to disturb ecosystems and introduce foreign biology into them, a more advanced race that could survive the complex social interactions necessary to not destroy each other or themselves with their technology, would most likely understand the devastation to our own social structure and ecosystem that could occur if they were to interfere.

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  4. 4. rlb2 4:45 pm 03/15/2012

    It is only logical to think that the hibernation of 50,000 years theory is wrong, because if they were 50,000 light years or more away we would hear them communicate when they were active. I have the real reason why we haven’t been contacted, I’m almost done with a paper I will publish. If I am right, we are doomed, maybe not this year but soon. This is one of the few times I hope that I am wrong.

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  5. 5. TaedWynnell 5:04 pm 03/15/2012

    Essentially the same “solution” is presented in Michael Kube-McDowell’s trilogy Emprise/Enigma/Empery. In the first book, we discover other humans living around Alpha Centauri when we first go there. In the second, we then start finding evidence of a number of human civilizations around the local stars, which points to a culling every 10,000 years or so. In the third, we bump into those responsible for the culling, and they are not friendly. I strongly recommend the first book (it’s among my favorite sci-fi, along with Ender’s Game and Dragon’s Egg), but the next two are just so-so.

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  6. 6. scientific earthling 5:22 pm 03/15/2012

    If our species is the basis on which we judge intelligence, then of course every intelligent species that ever evolved ended up exterminating itself, as we are so successfully doing now.

    A very good result.

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  7. 7. MadScientist72 5:42 pm 03/15/2012

    @ deven8703 – Or they’ve just decided we’re too primitive to bother with.

    @ rlb2 – “if they were 50,000 light years or more away we would hear them communicate when they were active”
    Only if they happened to be at a radio level of technology 50 KYA, which would have made them far to primitive for culling. Any technology sufficiently advance for interstellar travel would need to develop a form of communication that can bridge vast distances quickly enough to be useful (like subspace communications in Star Trek). And if we’re not listening in the right direction, at the right time AND with the right equipment, we’ll never pick up their signals.

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  8. 8. stevewriter 5:52 pm 03/15/2012

    Mass Effect has an anthropocentric storyline as does your thinking about aliens that might be out in the universe. I suspect that if aliens came to Earth they would bypass the large ordered active structure we call New York City recognizing that the order and activity of New York is a product of life, and not life itself. Here is a shock; they might also bypass large organisms—such as plants, animals, and even human beings—because they are not alive in themselves. From an alien perspective we could be seen as simply large cell cooperatives.
    Human reason is not nearly as innovative as cell evolution.
    Suppose that every person in the world is an engineer and we all love to think, talk, and improve various designs that we are working on. Currently the world population is about seven billion people, so we will say we have seven billion engineers. As an average, how often do engineers get little insights into some design: once a minute, four an hour, hourly, once a day, once a week? Often there is a core insight that a designer chooses to explore, and other insights come during the course of building out an initial idea. Suppose it takes a thousand small insights to produce a physical prototype over the course of a year, perhaps some engineers might get two prototypes built. Certainly, the rate of design improvement would increase. Each year we might get ten billion new prototypes representing a trillion or more small insights into the way materials can be put together to make things better. Ten billion is 10^11 prototypes, and ten trillion is 10^14 insights.

    Some cells can reproduce every twenty minutes if growth medium is available, and others may stay idle for millions of years. Suppose the average cell reproduces once a week—say fifty times a year. We know the cell is set up to duplicate its structure; that energy damage causes it to duplicate inaccurately, and consequently produce variations. We can think of each variation as a prototype. Cells are all prototypes, prototypes that succeed or fail according to the usefulness of their form and function in their environment. Suppose that the number of functioning cells on the Earth is about 10^24. That would generate 5X10^25 reproductive prototypes per year. Therefore, cells automatically generate 10^11 more trial and error prototypes in a year—that is completed physical structures—than a world population of engineers would have abstract insights into how to build their ten billion prototypes. We start with the first cell structure, the last common ancestor, that was already more sophisticated than anything humans have been able to make and then we add 5X10^25 each year for 4X10^10 years and that equals 2X10^35 opportunities to make cells that are more sophisticated, faster, stronger by trial and error.

    The cell’s ability to copy and maintain itself is pretty good. Suppose we say that half the number of reproductions are so good that they are functionally identical to the parent. Their are not improved or degraded. Suppose that significant useful improvements are one in a million over failures. We are still looking at 10^28 useful significant innovations for survival and reproduction in Earth’s environments. People can play with the numbers to attribute fewer or greater successful innovation to the reproductive systems of species, but when we look out at the natural world it is very difficult to deny the innovative success of cells because it is the process causing the diversity of life.

    The inventions of cells happen because of large numbers of duplicating individuals, and energy that damages but does not randomize life to extinction. Extinction is certain unless life can evolve a solution. So far life has escaped extinction through large numbers of variant individuals scattered to the far reaches of the world. The world is a finite place and there are rare anomalies that can take out the whole planet, or make it uninhabitable for life. Evolutionary invention by cells goes on continuously throughout the biosphere, but for evolution to work it must have physical access to the environment, and it must be able to produce large numbers of variant individuals near the environment such that outliers can extend life into the new area. Life is isolated to Earth’s oasis by gravity, and by a desert of space almost completely free of matter. We see great innovation by life over the course of evolutionary history, but we know of no success at leaping to other bodies in the solar system.

    It remains to be seen whether humans become a solution that is able to preserve life by lifting it off the planet and going into space, or whether we will add to the problems of life by the way we consume resources, produce toxins and cause extinctions in other cell lines. We are an evolutionary experiment. Our curiosity about life on other planets has caused us to send devices to those planets. We are trying to be careful to keep those probes sterile, but if we are careless, or intentional, we may move life to another place. That will buy more time for cell evolution to come up with the next solution, perhaps one that would extend life to the stars. Individual cells have no cares one way or another about what humans do, but the thrust of evolution is to use our rational capability, whether we intend for it to happen or not, to diminish vulnerability by starting colonies on other worlds.

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  9. 9. jgrosay 6:07 pm 03/15/2012

    Discussions about aliens seem purposeless to me. If they exist, they must have found a way of travelling that overcomes the enormous amount of time an intergalactic trip would take. Even if you consider speeds above speed of light, the problem remains that when they’re back home, nobody known to them will be able to welcome them, all will be dead for a long, long time. Evenmore: to reach our planet, they must know that it’s habitable, and looking for a planet sustainig life may be more difficult that finding a needle in a thousand haystacks. Finally, if those extremely low probability facts do occur, can anybody give a reason why aliens will show to mankind ?. We can’t be fully trusted, and giving us any information on where they come from, or how to get there, may put them in danger, now or in any future, situations may change. N Tesla, if I’m right he was, conducted an experiment that may represent something like a lighthouse indicating aliens, if they exist, that we are here. He built a coil, and produced electrical discharges, something like natural storm’s lightnings, that do emit waves in most of the radio and other frequencies, just to communicate with presumpt inhabitants of the Moon. Somewhere in the outer space, there are clouds of extremely low temperature gases, that act as natural amplifyers of this waves; when the emissions from the Tesla experiments reach this clouds some day, the clouds will amplify the waves, that as they were made using Morse code are identifiable as artificial, and will signal the whole near universe that we are here. None of us will living to see the effects of this, if there are some, but this reinforces the concept that aliens better never show. Salut +

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  10. 10. jtdwyer 7:50 pm 03/15/2012

    Regarding your statements about time & distances to events occurring at the center of the galaxy:
    “A moderately large outburst probably happened 300 years ago, a really big outburst may have happened 25,000 to 50,000 years ago – blowing vast ‘bubbles’ of energetic particles into space”:

    Your reference
    “…astronomers have recently spotted echoes of it in a large gas cloud called Sagittarius B2. The X-rays took 300 years to travel from the central black hole to the cloud, and when they arrived, they collided with iron atoms, causing them to emit X-rays.”

    However, it also points out that: “Since the center of our galaxy is 26,000 light-years from Earth, both the X-ray flash and the echoes we’re seeing now in Sagittarius B2 actually occurred a long time ago, roughly 26,300 years back.”

    Your reference regarding the enormous bubbles straddling the galaxy’s disk,
    actually states:
    “At more than 100 degrees across, the structure spans more than half of the sky, from the constellation Virgo to the constellation Grus. It may be millions of years old.”

    Also, as far as we know intelligent, technologically capable lifeforms take several billion years to develop and persist for perhaps 200 years, considering how we’ve managed to jeopardize our own continued existence. Depending on when that perhaps only 200 year window might occur for intelligent life on any other planet relative to our own window, any meaningful signals may have already passed us by, or we may not be around to receive them. Considering that any signal may take many thousands of years to reach us, we haven’t been listening for very long, any may not be for much longer…

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  11. 11. Metridia 9:53 pm 03/15/2012

    Thanks for the post- really neat. While Mass Effect may be wrong on the ultimate destroyer, it does explain a lot of the other observations and deductions relating to the apparent absence of sentient life traces. I hadn’t thought about the galaxy-center radiation bubble in this way, for example. However, it seems to be mainly spouting along the galaxy’s axis of rotation, avoiding the planets- does that bubble ever expand downwards, or is it only touch the plane of rotation at the center? Can you show a plot of how it looks through time?

    What about nearby supernovas? They might sterilize a portion of the galaxy ever so often, and since the galaxy is so small, unless one happened in the last 120k years we wouldn’t see it (right?). It might add just enough to the slings and arrows facing life that it cuts down on the number of billion-year stable biomes that can evolve sentients such that they are rare enough to be isolated. It’s been said I think that there is also a galactic Goldilocks zone, and planets closer to the center are just too much at risk.

    However, again it’s not at all clear whether we should expect contact of any type, given the difficulties of travel, the abundance of uninhabited temperate planets (we surmise), and the rarity of sentient evolution (on the order of one out of every 0.5 billion habitable planets would host sentience, based on how long it took us to get here?). Not to mention that with the advent of virtual reality, how long before aliens lose interest in further colonization?

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  12. 12. AveryAndrews 11:40 pm 03/15/2012

    Alasdair Reynolds’ ‘Inhibitors’ (Revelation Space series) are a similar idea.

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  13. 13. Mr.Tie 3:39 am 03/16/2012

    When we get out into interstellar space, we will find an alien beacon. When it is translated I believe it will say something along the lines of “warning system inhabited by psychotic apes: avoid direct contact”

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  14. 14. MadScientist72 8:36 am 03/16/2012

    @ stevewriter – I think your reasoning on alien avoidance of cities & large organisms is flawed. Logically, any organisms capable of interstellar travel would have to be “large cell cooperatives” (multi-cellular) in order to build spacecraft. That’s something that unicellular organisms just can’t do. Also, the development and construction of such a craft would require the cooperative efforts of many individuals – more than you’d find in a tribe, village, or even a small town – which strongly indicates that they’d be city-dwellers. This means that we would that bear enough stuctural & social resemblance to them to be of interest.

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  15. 15. MadScientist72 8:40 am 03/16/2012

    @ Metridia “the rarity of sentient evolution (on the order of one out of every 0.5 billion habitable planets would host sentience, based on how long it took us to get here?)”
    That assumes thour our evolutionary pattern is the norm, rather than an exception. Who knows – maybe the dinosaurs would have developed sentience if it wasn’t for the asteroid.

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  16. 16. Jerzy New 8:41 am 03/16/2012

    If humanity is a guide, advanced civilizations abandon space programs for domestic consumption, and exterminate themselves by using up resources.

    Seriously, the gap between required technology and one useful domestically is enormous.

    One might well expect that no planetary civilization can gather resources and know-how to realistic interstellar mission.

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  17. 17. Jerzy New 8:56 am 03/16/2012

    Another possibility is that advanced civilizations abandoned random information broadcasts into space and transmit on narrow, focused beams directly between planets. Reasons are energy efficency and avoiding noise.

    By analogy, in ancient cities it was common to hear speakers shouting messages very loudly from prominent locations. In modern cities such shouting is inefficent and prohibited, although there is a lot of quiet, directional communication going on.

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  18. 18. TheElfishGene 9:01 am 03/16/2012

    Mass Effect 3 is pure hokum!

    As a gamer and scientist i would have thought EVE Online would be a far more suitable candidate for this article.

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  19. 19. alanborky 9:49 am 03/16/2012

    Caleb (Yo Dog!) if they are there we can infer they’re ethical or sufficiently ethical to restrain any would-be exploiters among their numbers because up to less than a hundred years ago we didn’t even have nuclear weapons to resist any invasion; add to which there’re even reports of ufos displaying technology supposedly interfering with nukes and maybe even nukes’d be useless.

    But put it this way if you were thinking of moving into a new neighbourhood and you started knocking on doors to introduce yourself only to witness not only individual households tearing themselves apart over politics religion science wealth sexuality gender territoriality etc etc but demonstrating the only way they can get along is by attacking the members and properties of other households accusing them of constantly doing what you youself’re constantly doing wouldn’t you in the end decide the best policy’d be to stay as far as possible away from that neighbourhood until you saw some signs of everyone starting to calm down and grow up?

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  20. 20. albion 12:48 pm 03/16/2012

    Imo, maybe our present civilization is a multipurpose experiment of another light-years more evolved intelligent civilization. What for this experiment? Maybe to explore more on this special type of organized matter that inherit intelligent capabilities. I view it this way cause I can see our intelligence limitations reside in our proper cell cooperative. These limitations derives from 1-human’s lifespan, which doesn’t give our brain enough time for development through intelligent activities (exercises), and 2-the other limitation may reside inside human brain biological and biochemicals physical and functional factors. I mean this, I could understood very well basic math calculus or algebra and physics while studying at university, but getting into nowadays math problems and theoretical physics is very difficult for medium intelligent human beings, not talking about calculation and imagination skills to fully understand some aspects of the real physics behind FTL transportation and communication, if it is possible at all. Sensing these built-in boundaries makes me think we are an experiment result, not naturally allowed to go beyond the fence (for now) in a short time. But future genetics developments may allow us to control the reins of our species evolution, so we can surpass these boundaries or limitations. And this of course may happen if the outside factor (our master race or other factors) will allow us to do this biological upgrade, and if we will want to take this path. Grasping the knowledge for the theory of everything will require for us to intentionally biologically or genetically enhance human brain, and or human lifespan.

    If we are lucky we may witness and taste this century human lifespan modification.

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  21. 21. Caleb A. Scharf in reply to Caleb A. Scharf 3:11 pm 03/16/2012

    Thanks for all the great comments and thoughts. These kind of questions are nothing if not stimulating! In part this is obviously because the range of possible answers is so vast at the moment, we have very few meaningful scientific constraints. This is why, in my personal opinion, the ongoing effort to chart out exoplanetary systems is genuine progress. While we may speculate of life utterly unlike anything on Earth (including that which does not occupy planets), the actual search for Earth-equivalent worlds is probably the only way to begin to eliminate options – an approach that works across the sciences; if you can rule out certain hypotheses or parts of parameter space you can make progress. With that kind of strategy in mind it is also not crazy to take even the (very inventive) propositions in a piece of fantasy like Mass Effect a little bit seriously – in order to think of whether there is an obvious way to *disprove* them.

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  22. 22. Postman1 8:00 pm 03/16/2012

    @MadScientist72 I wrote a short story once long ago, based on the premise that the dinosaurs (velociraptors) developed into a smaller, intelligent species, and had just built a Mars colony when the asteroid damaged Earth and wiped out their species’ base. They decided to become a space based race, to avoid another disaster and evolved into the ‘greys’. Now their civilization in built on Kuiper belt object colonies and they continue to watch the home planet, to see if those rascally mammals will survive long enough to follow them into space.

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  23. 23. Postman1 8:19 pm 03/16/2012

    @Caleb A. Scharf – Perhaps those advanced cyber robots move through the galaxy at sublight speeds. When they find a nice planet with a promising species (apes?) they settle in and slowly nudge the species along the path to a technological civilization. When they are finally sufficiently advanced, the cybers reveal themselves and transfer the cream of the species into a new generation of cyber robots. The new robots then spread out to find new planets and the cycle continues.
    My latest scify theory.

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  24. 24. TemplarScribe 12:53 am 03/17/2012

    On the other hand…

    It’s also entirely possible that all of the thousands of UFO and USO sightings, ones that have been recorded since the time of Ezekiel and Enoch, are a perfect indication that we have indeed been visited by non-terrestrial intelligences. It’s also more than likely that in the modern age (post-WW II), that “they” have determined that we’re not yet ready to advance to the exploration phase of our quest for the stars.

    No need for cyber-robots or galaxy-wide cullings. All they need to do is quarantine us for a few hundred years, and our own greed for power, our self-destructive habits, and our lust for resources will do the job for them — unless we wake up, and start behaving like we belong in the company of far more advanced intelligences.

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  25. 25. ironis24 2:00 am 03/17/2012

    Great Article. It reminds me of another one I read in a blog concerning Mass Effect and the future of Robotics

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  26. 26. rlb2 1:31 pm 03/17/2012

    “The Voyage Home” Star Trek, “Live long and reproduce”..

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  27. 27. Ailblentyn 2:15 pm 03/26/2012

    The “explanation” is not that dissimilar to that implied in Studio Gainax’s (sublime) “Gunbuster”.

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  28. 28. Joel454 11:37 am 06/4/2012

    Old plot line. based on Larry Nivans Spacers wars.

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  29. 29. pkoneil 12:59 pm 06/5/2012

    The plotline is from a number of other very good sci-fi writers (and none end with an RGB color scheme). Jack McDevitt, “The Engines of God”; Greg Bear, “The Forge of God” and “Anvil of Stars”. All based on advanced civilization busters lurking about the galaxy. Each story much better than the Mass Effect series.

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