# SETI logically proves advanced intersteller civilizations **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 10, 2014, 6:10pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369 "2014-03-10T18:10:41Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [March 11, 2014, 3:05am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/41 "2014-03-11T03:05:51Z")
> [@Happy\_Fun\_Ball](#): > > Personally, I pray that SETI is correct that there is intelligent life out there in our finite galaxy, because there is bugger down here on Earth. We’re getting better. ---
**Author:** ![levdrakon](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Post date:** [March 11, 2014, 3:17am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/42 "2014-03-11T03:17:06Z")
> [@Smeghead](#): > > There’s a surprisingly solid argument to be made that we humans are simply the artificial mobile homes for E. coli bacteria. No matter how clever we think we are, we’re simply providing more and more cushy living space for our single-celled overlords. I’ve heard the quip that humans are merely an elaborate method for sperm to reproduce. Something like that. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [March 11, 2014, 4:19am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/43 "2014-03-11T04:19:21Z")
> [@pancakes3](#): > > It does seem odd that God would make the entire universe only to place life on a single planet billions of years after creating the universe. But think of poor Jesus! Does he have to get crucified on every one of the billions upon billions of inhabited planets? ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [March 11, 2014, 5:38am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/44 "2014-03-11T05:38:54Z")
> [@KneadToKnow](#): > > Okay, let’s get this straight: _is there_ or _is there not_ an intergalactic kegger? I gotta buy Solo cups. Not a kegger, but I hereby[direct you to the galactic liqour cabinet](http://news.bbc.co.uk/2/hi/science/nature/1589028.stm). ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [March 11, 2014, 5:48am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/45 "2014-03-11T05:48:19Z")
> [@levdrakon](#): > > I’ve heard the quip that humans are merely an elaborate method for sperm to reproduce. Something like that. Seems to me it was in one of the quip-runs in _Time Enough for Love_: the purpose of gametes is to make more gametes. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [March 11, 2014, 9:30am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/46 "2014-03-11T09:30:28Z")
> [@buddha\_david](#): > > Sorry, but I must side with **kanicbird** on this point, at least. > > Merely observing our own planet, we’ve discovered that life is hyper-abundant, including places where prior logic would assume no life could possibly exist – [extremophiles](http://en.wikipedia.org/wiki/Extremophile) thrive in fumaroles, [tube worms](http://en.wikipedia.org/wiki/Tube_worm) exist in the deepest, darkest ocean trenches, etc. Granted, all these lifeforms are very simple and non-intelligent, but such lively abundance compels us to accept the possibility, if not outright assume as fact, that abiogenesis is virtually guaranteed for any location _where conditions exist for life to appear._ Except that all DNA evidence proves that all that life is the result of a single event. How far it spread is therefore irrelevant. It’s still a single sample. Your argument is akin to saying that since half the people in town have a cold, that is evidence that the cold virus must have evolved lost of times. Nope. It doesn’t work that way. A single sample is still a single sample. What that sample does \*after \*it occurs can’t be used to infer anything at all about the chance of it occurring in the first place. We have exactly one sample of life. That alone would be nearly statistically worthless since it allows infinite degrees of freedom. But that sample is a precondition of any analysis. If it hadn’t occurred we wouldn’t be here to analyse it. That makes it. Logically and statistically we can;t infer anything from such a sample. > [@](#): > > Oh, and just because it’s freakin’ awesome, I fixed your TVTropes link: [Insane Troll Logic - TV Tropes](http://tvtropes.org/pmwiki/pmwiki.php/Main/InsaneTrollLogic) Thanks. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [March 11, 2014, 10:19am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/47 "2014-03-11T10:19:14Z")
> [@kanicbird](#): > > Since life happened here, we have to take that life happened elsewhere as well. No we don’t. High probability is not the same as absolute certainty. Taking this as axiomatic doesn’t prove a thing, though it does seem to demonstrate a strong desire to wish one’s belief into fact. ---
**Author:** ![Lightnin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lightnin/32/180_2.png) [@Lightnin](https://boards.straightdope.com/u/Lightnin)\ **Post date:** [March 11, 2014, 10:29am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/48 "2014-03-11T10:29:29Z")
1. We’ve found life damn near everywhere we’ve looked here on Earth. There’s no reason to assume that Earth is special, especially since it looks like there are an uncountable number of Earths in the universe. 2. In six thousand years we’ve gone from a hunter-gatherer to being so big that we’re affecting the climate. In 200 years we’ve gone from horse-drawn carriages to sending probes to another planet. In 60 years we’ve gone from slide rules to a globally connected computer network. 3. Space is freakin’ big. 4. Moore’s Law says that computer processing power will double every 18 months. Given those, my personal theory is there’s only a small window of time in which any given civilization even bothers to explore the universe. Traveling to the nearest star will take us a huge amount of energy and time- even if we can get to the speed of light, it’d still take us over four years just to get to it. It’s far cheaper to explore _inward_, to simulate the universe, rather than do the messy physical exploration of it. I think all of those alien civilizations are out there. I think they’re just exploring their own simulated universes instead of exploiting the real universe. Corollary: the number of simulated universes far outweighs the number of real universes, so therefore the odds are extremely likely that we live in somebody’s simulation. ---
**Author:** ![mandala](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mandala/32/95_2.png) [@mandala](https://boards.straightdope.com/u/mandala)\ **Post date:** [March 11, 2014, 1:08pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/49 "2014-03-11T13:08:31Z")
Most of the discussion I hear on this topic is about “intelligent life” capable of signalling their presence in some way. Is the presence of microbial, floral and unintelligent faunal lifeforms assumed to be inevitable? Is that the current scientific opinion, but we don’t have a hope in hell of detecting them, so we are scanning the EM spectrum instead? IOW, is life itself (of any kind) now considered/expected to be ubiquitous all over the galaxy / universe? ---
**Author:** ![Frazzled](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/frazzled/32/3368_2.png) [@Frazzled](https://boards.straightdope.com/u/Frazzled)\ **Post date:** [March 11, 2014, 1:26pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/50 "2014-03-11T13:26:30Z")
> [@mandala](#): > > Most of the discussion I hear on this topic is about “intelligent life” capable of signalling their presence in some way. Is the presence of microbial, floral and unintelligent faunal lifeforms assumed to be inevitable? Is that the current scientific opinion, but we don’t have a hope in hell of detecting them, so we are scanning the EM spectrum instead? > > IOW, is life itself (of any kind) now considered/expected to be ubiquitous all over the galaxy / universe? SETI was a shot in the dark. Had it worked it would have been cool but it hasn’t. NASA is currently working to find life supporting planets in nearby systems. It will work similarly to the Kepler Space Telescope. If you recall, that telescope worked by watching a stars light dim as a planet moved in front of it. By measuring the frequency of the dimming, and the amount the star dimmed, we can infer the size and location of the planet. As a result, we know that Earth sized planets in a stars habitable zone are frequent. The next step is to determine the content of those planet’s atmospheres using spectroscopy. We assume that there are gasses (including Oxygen) that will only be high because of life processes. This will help us find life in any stage of development, not just intelligent, and will give us a good idea of how frequently life can occur in the Galaxy. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 11, 2014, 1:35pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/51 "2014-03-11T13:35:51Z")
> [@mandala](#): > > Most of the discussion I hear on this topic is about “intelligent life” capable of signalling their presence in some way. Is the presence of microbial, floral and unintelligent faunal lifeforms assumed to be inevitable? Is that the current scientific opinion, but we don’t have a hope in hell of detecting them, so we are scanning the EM spectrum instead? > > IOW, is life itself (of any kind) now considered/expected to be ubiquitous all over the galaxy / universe? We simply don’t know. As others have pointed out, we only have a single sample to extrapolate from and with a single point you can extrapolate out to anything. So we’ll look for bio-markers we’re familiar with on exo-planets (like ozone, methane and oxygen) and search locally for physical specimens. We’ll be able to infer life by the bio-markers but the local specimens would be more interesting - are they similar to earth life because of similar chemical/evolutionary pressures or are they similar because life around Sol has a common source? Should be fun to find out. ---
**Author:** ![levdrakon](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Post date:** [March 11, 2014, 8:55pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/52 "2014-03-11T20:55:26Z")
> [@Blake](#): > > Except that all DNA evidence proves that all that life is the result of a single event. How far it spread is therefore irrelevant. It’s still a single sample. I wonder about this too. All life on Earth shares the same DNA? We’re all descended from a single type of pre-microbe? What are the odds of that happening so soon after Earth cooled enough for liquid water to collect on its surface? Why don’t we see new forms of replicating macromolecules? ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [March 11, 2014, 9:06pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/53 "2014-03-11T21:06:26Z")
> [@levdrakon](#): > > I wonder about this too. All life on Earth shares the same DNA? We’re all descended from a single type of pre-microbe? What are the odds of that happening so soon after Earth cooled enough for liquid water to collect on its surface? Why don’t we see new forms of replicating macromolecules? Yes, ALL available evidence points unequivocally toward a single origin of life. The odds of this having happened are one, because it did happen. “So soon after” is a matter of opinion, and again, we don’t really have the data to know how likely it is to happen. The reason we don’t see new life gradually building up out of nothing is because it would quickly get eaten long before it managed it. There’s a HUGE difference between a primordial soup right before the first life form manages to organize itself together, and a primordial soup a few centuries after. The first life forms would almost certainly have been pathetic - barely able to manage to be alive at all. The only reason it would have survived would have been because it was alone. Once life gets going and natural selection takes over, and especially when competition sets in, it’s a whole different ballgame. No more free, easy ride for those pathetic little proto-cells. It’s eat or be eaten; kill or be killed. Then, of course, oxygen came along and fucked everything up even more. ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [March 12, 2014, 12:30am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/54 "2014-03-12T00:30:55Z")
> [@Lightnin](#): > > . . . 4) Moore’s Law says that computer processing power will double every 18 months. . . . Well, yes, but Malthus’ Law also says that the human population will double ever few hundred years. It would, if left absolutely unchecked and in an environment with unlimited resources. Moore’s Law is wonderful – we all love having terabytes in our home computers! – but it’s a limited phenomenon, and cannot be claimed to be a fundamental law of nature. It’s like watching Intel or Microsoft or Apple stock prices explode: they did…and then they stopped again. Instead, the thing to take away from this is that things can change rapidly. Advanced civilizations might blow through an entire technological regime in only decades. We pretty much will have drunk up all the petroleum in the world in a spasm of only 200 years. ---
**Author:** ![That\_Don\_Guy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/that_don_guy/32/538_2.png) [@That\_Don\_Guy](https://boards.straightdope.com/u/That_Don_Guy)\ **Post date:** [March 12, 2014, 12:51am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/55 "2014-03-12T00:51:25Z")
> [@kanicbird](#): > > 2- The earth/solar system/sun is not unique, but common and made of common material. Since life happened here, we have to take that life happened elsewhere as well. Why? Some planet had to be the first - why not Earth? ---
**Author:** ![Lightnin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lightnin/32/180_2.png) [@Lightnin](https://boards.straightdope.com/u/Lightnin)\ **Post date:** [March 12, 2014, 10:49am UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/56 "2014-03-12T10:49:20Z")
> [@Trinopus](#): > > Well, yes, but Malthus’ Law also says that the human population will double ever few hundred years. It would, if left absolutely unchecked and in an environment with unlimited resources. > > Moore’s Law is wonderful – we all love having terabytes in our home computers! – but it’s a limited phenomenon, and cannot be claimed to be a fundamental law of nature. It’s like watching Intel or Microsoft or Apple stock prices explode: they did…and then they stopped again. > > Instead, the thing to take away from this is that things can change rapidly. Advanced civilizations might blow through an entire technological regime in only decades. We pretty much will have drunk up all the petroleum in the world in a spasm of only 200 years. Well, yeah. That’s kind of what I mean. I believe that there’s really only a narrow window of time in which any given civilization has the resources _and the inclination_ to expand outward into space. It’s far cheaper to just stay home. ---
**Author:** ![mandala](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mandala/32/95_2.png) [@mandala](https://boards.straightdope.com/u/mandala)\ **Post date:** [March 12, 2014, 5:15pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/57 "2014-03-12T17:15:50Z")
> [@Lightnin](#): > > Well, yeah. That’s kind of what I mean. I believe that there’s really only a narrow window of time in which any given civilization has the resources _and the inclination_ to expand outward into space. It’s far cheaper to just stay home. Not to mention a government that cares, and an enabling political climate. I mean, if something catastrophic happened today to the US, humans can kiss their space ambitions goodbye for the foreseeable future. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [March 12, 2014, 5:24pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/58 "2014-03-12T17:24:40Z")
> [@Lightnin](#): > > Well, yeah. That’s kind of what I mean. I believe that there’s really only a narrow window of time in which any given civilization has the resources _and the inclination_ to expand outward into space. It’s far cheaper to just stay home. I think the idea is that we are currently pushing the boundaries of what the Earth is capable of supporting: growth is an inherent, inevitable part of life, so, logically, we will need to use space, and figure out relatively practical FTL travel in order to keep living (“growing”). _We need more space_. The unending growth paradigm is questionable, though. Since we have already over-stressed the planet’s biosphere, to the extent that we may have less than a century before it stomps us back to Amish life, or to extinction, the likelihood that going into space to ease our local pressures will be happening before those pressures overwhelm us is disingenuous at best. We, here, have two major hurdles to overcome. The first, obviously, is the technical one, making some kind of useful, practical, mass-producible FTL system. But perhaps the bigger hurdle is the social one: getting enough of us on the same page that we can focus on that goal and achieve it without killing each other along the way, or getting involved in massive IP litigation that stalls the project before it can get anywhere. And the social factor is important as well because we simply cannot go out into the vast guns-a-blazing. We just do not have a suitable attitude for interstellar travel unless we learn to think more sensibly. Assuming that other planets have fostered some form of life bearing abstract intelligence, I think it is fair to guess that they would have faced very similar issues, because knowledge and learning can only develop dynamically in a social species (or in some kind of creature that gains knowledge by somehow absorbing and auto-integrating the genetic material of other beings that it eats or has sex with). As has been said before, basic intelligence is a pretty normal evolutionary development (predator avoidance, food discover, tool use), but abstract intelligence (language, art) is anomalous and, quite frankly, superfluous. ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [March 12, 2014, 8:59pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/59 "2014-03-12T20:59:37Z")
> [@Lightnin](#): > > Well, yeah. That’s kind of what I mean. I believe that there’s really only a narrow window of time in which any given civilization has the resources _and the inclination_ to expand outward into space. It’s far cheaper to just stay home. Oops! Sorry, I thought I was rebutting you. (Embarrassed.) David Brin has an amusing argument for The Great Silence: people from advanced civilizations don’t contact us, because they’re all plugged in to their internet equivalent. They aren’t talking to us, because they’re all much too busy sharing pictures of kittens on pianos. ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [March 12, 2014, 9:02pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/60 "2014-03-12T21:02:49Z")
> [@For You](#): > > . . . basic intelligence is a pretty normal evolutionary development (predator avoidance, food discover, tool use), but abstract intelligence (language, art) is anomalous and, quite frankly, superfluous. It is frosting on the cake…but the frosting is the best part of the cake! Sure, we’d have continued to do pretty damn well if we’d never gone much beyond “Lucy” and the early Australopithecines – just being big and quick and good at running pretty much assured our survival. But, oh, the joys of abstract knowledge! [Previous page](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369.md?page=2) [Next page](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369.md?page=4)