Drake on Drake: ET Life A Certainty 421
astro writes "Frank Drake, Chairman of the Board of Trustees of the SETI Institute applies Occam's Razor to his own Drake equation: 'Life should appear very frequently on other Earth-like planets. There will be microbial life nearby the solar system.' The simplest scenario is that 'Not Life' has a nearly identical number of assumptions as 'Life.' The contrasting view is that experimentation can prove it--but how many times did life independently create itself while the Earth changed through the whole spectrum of what biological forces might conjure up elsewhere. A sample size of 1 is in fact an experimental sample size of many--just here during Earth's climatic history."
1 != Many (Score:4, Interesting)
Ummm....Im sorry, but I thought that there was, perhaps many singular events where life was formed billions of years ago, but simple evolution and extinction dont "scale" to be equivalent to non-life becoming life.
Furthermore, I recall reading a book..."Probability 1", that spend several chapters mucking around before submitting a "proof" that there must be intelligent life elsewhere...As I recall, it hinged on one instance of life, which is us.
Re:1 != Many (Score:3, Interesting)
Re:1 != Many (Score:2)
Re:1 != Many (Score:2)
What we don't know for sure is whether those impacts/upheavals were enough to sterilize the planet or left a few isolated pockets of life from which it re-emerged.
Re:1 != Many (Score:2)
The "rare earth" people that Drake is debating actually assume that such bacterial life is very common, but that multicellular life is very rare, so it's presense on primordial earth prior to mass extinction events does nothing to dispute their claims. (indeed, it is one of their explicitly stated expectations)
It should be pointed out though that if we are talking about complex life we DO have a larger sample than 1 right now. Both Venus and Mars are "earth-like" in astronomical terms. They are about the right size and about the right distance from the sun. But they are not *quite* right. Mars has frozen and Venus is gripped with runaway greenhouse gases, they are each a "little too close" and "a little too far". Though if they had gotten the atmospheric chemistry right I think their distance from the sun could have been compensated for - imagine if their positions were reversed, if Mars had the thick atmosphere with a lot of greenhouse activity and Venus had the thin atmosphere - who knows? As it is they are fairly good examples of what happens if just a few variables on your "earth-like" planet are wrong by just a little (in astronomical terms). Even Mercury with no atmosphere is an example of not only being too close to the sun (and thus too hot) but of being caught in tidal lock (so despite the intense heat on one side the atmoshpere freezes out on the other) This would presumably happen to any planet so close in, even if the star were smaller and a mercury type planet was only getting as much solar energy as earth is getting further away from a larger star.
It is not unlikely that if we could start visiting other systems we would find a *lot* of planets that were candidates to become truly earth-like but failed because they got just a few variables wrong by just a little bit. Even a nearly identical planet to Earth - exactly the same size, exactly the same distance from exactly the same sized star, with exactly the same chemical composition would have a high probablity of succumbing to either runaway greenhouse gases or having it's atmosphere freeze out if it's atmospheric composition was not regulated by the action of plate tektonics & continental weathering or if it's tilt was not regulated by an oversized moon or if it just had the bad luck of being hit with a really big comet (a very likely occurance without a "jupiter" nearby sucking up or pushing out all the debris).
Re:1 != Many (Score:3, Informative)
One possibly critical datum missing from that analysis relates to Earth's history. Earth has a relatively thin crust and the combination of tectonic motion, subduction, and vulcanism recycles elements back to the atmosphere after they'd been locked up in rocks. (Actually you do hint at this in your last para.)
Mars seems to be small enough that it has solidified down far enough that there's no more cycling of the crust and thus the oxygen and hydrogen locked in the rocks stays there, also any free hydrogen (from the ultraviolet lysis of water) escapes to space before it can recombine, thus Mars now has a very thin atmosphere.
Venus may be large enough, although that isn't certain. It certainly seems to have continental masses but I don't know about any active volcanism. It's heavy enough to retain atmosphere though -- too much of it, as you point out.
It's possible that the reason Earth escaped Venus's fate has less to do with the distance from the Sun and more to do with the formation of our Moon. Current theory is that late in the formation of the solar system, the proto-earth was smacked by a Mars-size protoplanet which literally splashed a good chunk of the proto-Earth into space, some of which condensed to form the Moon. This has several implications. The lightest elements would have boiled away in significant quantity, so there's just less of them around to form a thick atmosphere (hence less runaway greenhouse). The medium light-weight elements (that form crust, particularly continental crust) were greatly reduced, some of them forming the Moon (so in one sense, the Moon is the 8th continent), meaning that tectonic circulation has an easier time of it. (The heat from that impact might also have some effect there, although I think that would be dissipated by now.)
All of which leads to the (somewhat depressing) conclusion that Earth is habitable only because of a really unlikely sequence of events (much more unlikely than merely forming at the right size in the right place). OTOH, observation of our own solar system and some of the very strange (to us) places on Earth that life survives and thrives indicate that there could be a lot of places that primitive life exists. Star Trek's "Class M" planets are probably pretty darned rare, though.
(Oh, BTW, Mercury isn't in "tidal lock" like the Moon is with Earth, but in a 3:2 tidal resonance with the Sun.)
Re:Statistics are fun (Score:2)
Hitler, he only had one ball,
Rommel, had two but very small,
Himmler, had something sim'lar,
But only Goebbels, had no balls, at all.
--heard this was a British infantry bit in WWII
Ockham vs. Drake, the remix (Score:4, Interesting)
Francis Drake - "My whole life's work, from SETI to the Drake equation to the 1970's Arecibo radio transmission, depends on their being aliens somewhere in the Universe, so I'll pop up every year or so and assert that ET does exist so I won't be a failure.
Time vs. Certainty (Score:2, Insightful)
I'm always leery of the term "Certain" when a key premise is time on the order of billions of years.
How can this view be proved or disproved? (Score:5, Insightful)
Although I tend to believe there is intelligent life in the universe outside of Earth, I'm not sure this argument serves as proof or even a good starting point for a proof.
I think we ought to just be content saying there might be a chance that other intelligent life exists and we'll get to proving it through empirical data. Then if everything checks out we can go applying theory, probability, and predictions. Until then, this stuff is simply philosophy - the earth was flat until we found out it was not.
Re:How can this view be proved or disproved? (Score:3, Insightful)
After all, philosophy has its place too. Without getting our minds around the possiblities, we will have very little success in conducting our search (or even convincing those with resources to finance the searching, though more likely than not, if life is found, it will be an accident during an economic/political endeavor).
Re:How can this view be proved or disproved? (Score:2, Insightful)
If you're worried about this you wouldn't probably understand any proof ever laid out to you either. It should go without saying that there won't be a proof, ever, until we find an ET or they find us. A lot like us atheists will have a hard time proving there isn't a god.
This may sound trivial, but it really isn't.
Proving something nonexisting outside a purely theoretical system is rather difficult. Because any attempt to show a contradiction in it's existence is quite impossible.
The artice on the otherhand is more about showing a reasonable doubt, if you please, to justify believing in et life. More like showing the reasoning behind such beliefs. I, for one, found few rather interesting points of view there.
Re:How can this view be proved or disproved? (Score:2)
Actually, a number of observers have described SETI as junk science, pseudo-science, bad science, or non-science mainly because of the non-falsifiability of the main hypothesis. While there are differing ideas of what strictly constitutes the "scientific method" it is true that such non-falsifiable investigations don't necessarily meet the bar of being a real "science".
However, I don't think philosophy is the right discription either - I prefer "exploration" - a venture that has traditionally led directly to many of the greatest scientific discoveries and revolutions. The value of exploration to scientific progress is undeniably large, although it is fair to subject such non-falsifiable investigations (especially expensive ones) to strong scrutiny and healthy skepticism.
Perhaps "scientific exploration" is the best description since the bulk of participants are trained scientists who employ the tools and reasoning of science, and search for evidence that will be suitable for falsifiable experiment in the normal scientific sense. Aside from the criticism of non-falsifibiliy, most of the measures employed by these scientists are subject to normal scientific justification and accountabiilty - often refined through induction, statistics, peer review, and debate.
Re:How can this view be proved or disproved? (Score:2)
An interesting aspect of the argument is that L decreases as societies become more technologically advanced (on Earth, at least). Whether this is the case after a certain "threshold" for technology is less clear, though, but it certainly seems plausible that at any given time there may be a species capable of communicating with no one else to talk to.
well. (Score:5, Insightful)
This has a unintended but frightening implication, however.
Humans have existed as a sapient, technological species for approximately 30000 years (and that's generous, really). That means that in the cosmic equivalent of a the beginnings of a heartbeat, we've gone from caves to extraplanetary exploration, and our technology curve will only accelerate from here on out.
Considering that it took almost no time to get here, it will take even less time to get to point where we would be leapfrogging across the galaxy, colonizing everywhere. Within the next 30,000 years we'll have had more than enough time to have distributed explorers to every inhabitable/explorable planet in the galaxy.
The question, then, is why hasn't anyone found Earth yet, if the probability for life is so high? Either every civilization gets wiped out long before they can begin galactic exploration (without exception--a pretty difficult thing to imagine, unless you're an apocalyptic environmentalist), or, perhaps more frightening in an indirect sense, there simply aren't any other intelligent civilizations in the galaxy.
You'd think that even if ancient astronauts had found Earth, we would have uncovered at least SOME sort of artifact. After all, playing the probabilities, if one civilization found us, it would be overwhelmingly likely that many, many others would be able to, and would. So far we've got nothing.
It's a difficult reality to accept, but it may very well be that we're alone in the galaxy, and perhaps even in the universe.
Re:well. (Score:2, Insightful)
You assume a few things:
1-that other life is like us.
2-that other life is interested in or capable of interstellar travel
3-there is no third thing
4-no poofters!
There's no guarantee that other life-forms are anything remotely like us, assuming they exist at all. Assuming evolution is a valid model for the creation of life, we were extremely lucky to have developed this far. Indeed, the sheer variety of life on Earth is amazing when you consider that evolution's functions rely on random chance.
I think it's more likely that other life in the galaxy (let's think small for the moment) is so totally alien and different from us that we wouldn't know it if it paraded up and down in front of us holding up a sign, in English, which read, "We're not from Earth!"
Then again, I like "Enterprise", so what do I know? ;)
another possibility (Score:5, Insightful)
Re:another possibility (Score:2)
I've seen a few posts here assuming that FTL travel is necessary for any kind of interstellar exporation or colonization. It isn't.
Even by conservative projections of technology development, it will soon be possible for starships to reach a significant fraction of the speed of light (say, 10%) by using lightsails pushed by lasers in solar orbit. (The ships would decelerate at their destination by releasing a second sail that would reflect the light from the home laser back to the ship.)
At 0.1c, a ship could cross the galaxy in about a million years -- an eyeblink compared to the lifespan of the universe, which is measured in tens of billions of years. Granted, one ship couldn't make that journey, so you'd need some kind of self-replicating robot probe that built new lasers at each star it stopped at, but the point is that the galaxy can be explored in a reasonable amount of time at speeds well less than the speed of light.
TheFrood
Re:another possibility (Score:2, Insightful)
The problem with this is
KE = 1/2 mv^2
Hitting a 1 mg particle at 10% the speed of light would do serious damage. Thats about 10 times as much energy in a 1g bullet at 300 m/s.
So while warp-drive might not be needed, shields sure would.
Re:another possibility (Score:3)
It launches a second sail ahead of itself, the laser hits that and it reflects the light back; the second sail gets pushed away and lost, but if you can focus it you can keep it pointed at the main craft and slow it down.
I'd draw a bit of ASCII art, but SlashDot is too lame to let me use spaces. Instead, look at something like this paper [transorbital.net], describing a roundtrip lightsail.
Re:another possibility (Score:2)
Assume that the probes travel at
So if any one of those 100 billion stars in our galaxy had intelligent life that hit that point any time 1.5 million years ago or longer, at least one of those civilizations should own the galaxy.
To my mind, there are only a few possible answers: either there is some super-powerful civilization that conserves new life, we live in some kind of simulation run by other intelligent life, or intelligent life so rarely makes it to that point that the chances of there being another civilization are slim.
The problem is that natural selection should apply on these scales like it doesn on a planetary scale. Only the life forms that breed from planet to planet are likely to survive in the long run. Where are they?
Re:another possibility (Score:2)
Re:another possibility (Score:2)
Of course, you'd need a *lot* of energy and some really quite impressive shielding (say, a huge chunk of ice you can refill just about anywhere, ala The Songs of Distant Earth), but given the timeframe we could have to develop that sort of technology, it's not that far out.
Of course, for an external observer, it would be impressive to cross the galaxy in 30k years
Re:well. (Score:5, Interesting)
Re:well. (Score:4, Funny)
For you youngsters, Leo was talking about the brightest man ever, i.e. John von Neumann.
Re:well. (Score:2, Interesting)
Re:well. (Score:2, Insightful)
Perhaps an overwhelming number of forms of life never even come close to becoming intelligent enough (no matter how long evolution has a crack at them
Of those tiny fraction maybe:
- they have been wiped out by disease or astronomic cataclysm (sp?) which is very posssible for every civilization given the generous millions of years it took us to evolve (heck, its already happended once 65m yrs ago that could have almost wiped mammals out as well as prehistoric animals/plants)
- they have caused their own demise.
The latter is probably the most likely of the two, as anyone looking around at the world today can attest to; you've got a bunch of crazies ready to kill other people in the name of [an invisible man] and plenty of ways to do it. Nations fighting for oil, riots, famine, poverty...Name yer poison: shall it be deadly biological agents, nukes, or world-wide war?
Maybe we are just destined to destroy ourselves.
And maybe that old twilight zone episode was right: people are the same throughout the universe.
Re:well. (Score:2)
Your second point well maybe i'm a hopeless optimist, but i think it's a rediculous idea. The thought that we would go against everything we know, ie the fundamental instinct of survival, and just blow ourselves up for some petty war or whatever, doesnt seem so likely to me. Sure we'll commit mass genocide, use chemical weapons, and firebomb/nuke hundreds of thousands of civilians, but we wont bring it apon ourselves, many of us will continue to survive despite our worst efforts...
Re:well. (Score:3)
Taking your 30,000 year figure for example, that's only 0.00001% of the time that there has been life on this planet. As a duration for a technological species capable of communicating across interstellar distances, that is incredibly optimistic -- our track record is barely a century so far, and that's being generous.
Re:well. (Score:3, Insightful)
Maybe because a light year is a really long distance to travel, and Star Trek warp drives are not based on any reality in the universe?
Re:well. (Score:3, Interesting)
It might sound silly, but perhaps the need to explore is something only us earth-bound folks feel the need to do.
What if, say, a greatly advanced life-form existed on Neptune, but was content to create a "utopian" life on their own planet, with no need to explore?
The one thing we as humans fail in every time is that we assume all these aliens will be similar to us in their needs to explore, propogate, and conquer.
Maybe the answer is that they don't care about us, until we come to them.
Just some random ramblings
convergent traits. (Score:2)
Would it not be likely that these traits would appear in alien evolutionary environments? Many examples exist of evolutionary convergergence traits such as wings (birds, bats, insects).
Behavioral explanations for Fermi's paradox (Score:3, Insightful)
I personally believe that the development of tool-using, communicative intelligence is very difficult in evolutionary terms, and is thus exceedingly rare. Remember how quickly unicellular life developed on earth, and how late intelligent life arose. At most, there may be only a few civilizations scattered through our galaxy; but it is very possible that we are the first, the only technical civilization in the galaxy.
Re:well. (Score:2)
Re:well. (Score:2)
Agricultual Revolution -> Industrial Revoulution -> Information Revolution -> Matrix Style Pods That Will Extend Our Lives and Provide Us With Every Imaginable Pleasure
Maybe other extraterrestrial civilizations have followed this pattern, if they can't get around the great distances to travel. It's a common science fiction construct that the last human will die jacked into some computer with a big smile on their face.
Re:well. (Score:2)
Re:well. (Score:2, Interesting)
Considering that it took almost no time to get here, it will take even less time to get to point where we would be leapfrogging across the galaxy, colonizing everywhere. Within the next 30,000 years we'll have had more than enough time to have distributed explorers to every inhabitable/explorable planet in the galaxy.
----
1. I beleive the "higher life forms" claim is already satisfied if there are worms present. If they are really demanding, think of rats.
2. The earth might have been 'found' and visited, way back when, when they built stone henge and those outlines in the andes, but then they decided that we are too dumb and anyways we have only one opposable digit per appendage, so they left us alone and put a sign up; "Do not Disturb", so all that happens every now and then is a few adolecent aliens swoop by in a flying saucer they stole from their father and abduct a few people of whom they know that no-one will ever beleive them. And about the 'Artefacts', either they are there and we are looking at them, or
3. Time. The biggest barrier in Space. If we are around only since a half a heartbeat, other civilisations might have sprung up, conquered the galaxy and then contracted Space Herpes and died out. Rise and Fall of empires.
4. Life has evolved as many times as they claim, and as many times they have been in half a heartbeat at the brink of leaping from planet to planet, but then decided that they don't like they way the guys from the other continent pronounce "Smoerebrod" and start a war that destroys all inhabitants of the planet. Maybe not getting wiped out is the final IQ test.
I am basically agreeing with you, but there too many factors that could make their theory work.
Flup
theflup@yahoo.com
Life numbers (Score:2)
Cultural and technical changes - progress if you will (but I won't) - require lots of head space. "Traditional" cultures are traditional because they are stored solely in the heads of their carriers. Traditional cultures are extremely vulnerable to the loss of members, if the society is too complex. Thus simple cultures survive by redundant storage of the essential information that defines the operational aspects of the society. Once the ability to store information "extrasomatically" comes along (i.e. writing) more complex civilizations become possible and technical change can occur more rapidly because a literate civilization can support intellectual as well as craft specialization.
If you consider it, it is fairly obvious that population growth rates and technical advances heterodyne on each other. The problem that can affect the number of intelligent species (as we understand intelligence) that can make into space comes as the growth of population passes the "knee" in a yeast growth type curve. At that point we have entered a race between environmental degradation, technological advance, and the exhaustion of critical resources. If and only if technological advance can establish a population off planet, if and only if technological advance can offset environmental degradation and resource scarcity can species then start to really explore space.
You can imagine from this that some intelligent species with very slowly growing, or stable populations probably have little reason, except perhaps curiousity, for leaving a planet. More might reach the yeast growth stage, fail in the technical-environmental-resource arena and become extinct or under go drastic reductions. Another few may actually make it off their home planet and into interplanetary or perhaps intersellar space.
Probably on a majority, nothing we could recognize as intelligence ever appears.
We won't be contacted because... (Score:2, Interesting)
or
if the civilisation is more advanced than us, then they have nothing to gain.
I think.
Re:well. (Score:2)
Re:well. (Score:2, Insightful)
There is one more option... What if we are not yet intelligent enough to understand beings outside our immediate circle of vision, in which we are the kings of the animals? The lion, in Disney's safari, for one, is still totally convinced that he too is the king of the animals. He cannot see us or understand us or even detect the way we control his being.
Here's a twilight zone thought because it's 4:40am: What if our communal emotional climate shifts, our tragedies, our discoveries are caused directly by the animals that keep us? What if earth is a stop in a giant zoo
Ponder that as you go to sleep tonight...Re:well. (Score:3, Insightful)
I don't see why it necessarily should. Just because we had a golden couple of centuries of invention does not mean either that it will go on forever, or that people are willing to continue spending time and energy on it.
Just look at manned travel beyond our orbit: we did it, mostly out of some competition with the Russians, but budget priorities have shifted now. We seem to be more given to earthly pursuits, survival in the case of some, hedonistic pleasures for the more lucky.
Too many assumptions (Score:2, Insightful)
1. We would want to explore and colonize the galaxy.
It's not clear if we would want to do it. First, humanity may reach a point when physical exploration would make no difference to the amount of knowledge and physical space would not be needed for progress, just like horses are no longer needed for transportation.
Another reason for not exploring could be extreme enviromentalism: leaving the galaxy alone to preserve the original environment.
2. We would develop a technology for such colonization.
As already mentioned, faster than light travel may not be possible.
3. We are not yet found and colonized.
ET could be here already. They could be just indistingushable from natural phenomena. Maybe we are being observed, like a mother observes a baby in a cradle.
Interesting twist - dinosaur killer asteroid was dropped intentionally to speed up evolution.
You say "we would have uncovered at least SOME sort of artifact". Now, if they indeed have left an artifact, how do you know we would not take it for a natural object? What if moon is an artifact? Imagine CroMagnon finding a CPU chip.
In short 30,000 years we developed this level of technology. Where are we going to be in just another 100 years? I would not even bet that in 100 years humans would be biologically the same as today. What if ET is 100,000 years ahead of us? How would they be different from God?
One thing is clear - the SETI program in its present form (search for EM transmissions) is a waste of public money.
Re:well. (Score:2)
I think a more likely time frame is around 5 million years. That may sound like a long time, but really, it's a very short time in the geologic and cosmologic sense. Were it to take a mere 5 million years, it's still likely that another intelligent, explorative specie, would have colonized the galaxy by now, if they existed.
I believe we'll find signs of single-celled life to be abundant. I think multi-cellular life is going to be far less common. Also, I think we're beginning to find that most solar systems are not inhabitable.
First of all, you can pretty much wipe away between 1/2 and 2/3 of the stars in the galaxy as being too close to the galactic center, and therefore in too radioactive a zone to support any sort of stable life.
Next, most extrasolar planetary discoveries have found the Jupiter-like planets to be in either close orbits, or highly eccentric orbits, making the possibility of a planet in the habitable zone highly unlikely (more likely it's tossed outside of its system or into its sun due to the gravitational effect). I think before these discoveries, most scientist assumed that Earth-like planets, or at least conditions favorable for one, were far more likely.
Of the 100 or so extra-solar planetary systems discovered, only two are capable of having a planet in the habitable zone, and we of course haven't been able to see yet if they even do. Over the next decade, we'll likely learn much more about this.
Re:well. (Score:2)
How long have humans had technology capable of receiving a radio signal over interstellar distances? How long have we been broadcasting signals strong enough to be picked up at those distances? 50-60 years?
So all we know is that there is no civilization as advanced as us with comparable technology within 50 light-years, or no civilization that has heard us without leaking anything that we can currently receive and responded within 25 light-years of earth. These distances are trivial relative to the size of even this galaxy. What if, though a quirk of cultural development, there's another civilization on our doorstep who never liked radio and wired everything? Something as simple as that would make them almost impossible for us to find them.
It's a difficult reality to accept, but it may very well be that we're alone in the galaxy, and perhaps even in the universe.
It is entirely possible that, due to civilizations running their course and either decaying or transitioning to another type of life in which this galaxy is irrelevant, we are the most advanced civilization around at the moment. It's also possible that we are the least advanced civilization around, that no other civilization has used radio for thousands of years, and that we are quarantined until we make it into deep space on our own. No-one knows yet.
There *may well be* a thriving ET colony... (Score:2)
But I've also seen one speculation that the human race is actually rather *early* on the galactic scene. There needs to have been a generation or two of stellar death to give us our heavier elements, for instance. Now *early* can have many meanings, but as long as we're playing statistical games, we have to consider how many intelligent species arise and survive their warlike tendancies. We still haven't passed that hurdle.
Finally, in the words of Douglas Adams, space is big. I suspect Star Trek and Star Wars have given us an underappreciation for just how big space is. On another subthread, someone asserted that you can't have an empire without FTL. Someone else refuted, and said that you could have a Federation.
I'll argue that you can have neither federation nor empire without FTL, and possibly neither with, for that matter. Most problems are local, so the problems of the "Federation" would rapidly diminish. Even directed communication at lightspeed would be barely worthwhile beyond a "We are still here, how about you?" type of message. Interstellar distances are *so* big that by the time you could for instance ask for a piece of technology from the mother world and get a reply, you could have developed it, yourself. Piers Anthony's Macroscope may have fingered interstellar communication most succintly - "Here we are, and look what we can do!"
Even the existence of FTL may not appreciably change this. The Enterprise runs around on antimatter, but other than seeing the moon of Praxis blow up on one movie, we've seen nothing about the source. Antimatter is just a dense means for storing energy. You'd need a Dysan sphere to generate enough antimatter for all of those starships running all over the galaxy, and we know the Federation doesn't have one of those. They neatly ignore the problem so that they can have stories.
So whether FTL is impossible or horribly expensive, chances are there wouldn't be a "wave of colonization" across the galaxy. As each wavelet reached a habitable planet, it would become immersed in "local problems" for several hundred or thousand years, and would have to pass its own fittness test for subsequent interstellar travel.
Re:well. (Score:2)
What, exactly, makes this seem like a reasonable assumption to you? You're suggesting that, perhaps driven by Moore's law or something like it, we're on a geometrically accelerating course, but why does that have to be the shape necessarily?
Why not an S-curve, that settles down after a few decades or centuries? For that matter, why not a bell curve, where bad things happen and a few centuries from now those of us that are left go back to being hunter-gatherers?
Your whole point depends on the assumption that, because technological progress is supposedly inevitable for us, so it must be inevitable for other extraterrestrial civilizations as well, and since thiis geometrically accelerating evolution tends towards infinity, it should be a simple matter for us to dig up examples of other infinitely advanced civilizations. But if you remove the assumption of infinite acceleration, both for us and for our interstellar neighbors -- and really this assumption sounds specious at best to me -- then this whole chain of thought becomes much less necessary. Yes, it seems plausible that we should be able to find evidence of advanced civilizations out there somewhere, but the existence of them isn't necessary for there to be intelligent but perhaps not interstellar civilizations that maybe we'll never be able to trace.
Re:well. (Score:2)
Paltry? Do you know how many stars/planets there are in our galaxy? In the universe? Reachable? We haven't even gotten out of our solar system. That is like moving from one grain of sand to another on a beach.
Considering that it took almost no time to get here, it will take even less time to get to point where we would be leapfrogging across the galaxy, colonizing everywhere. Within the next 30,000 years we'll have had more than enough time to have distributed explorers to every inhabitable/explorable planet in the galaxy.
That is quite a leap you are making. Evolving on your own planet, and being able to traverse the galaxy are entirely different things. And do you know what is outside our galaxy? Who is to say that other life exists in our galaxy?
The question, then, is why hasn't anyone found Earth yet, if the probability for life is so high? Either every civilization gets wiped out long before they can begin galactic exploration (without exception--a pretty difficult thing to imagine, unless you're an apocalyptic environmentalist), or, perhaps more frightening in an indirect sense, there simply aren't any other intelligent civilizations in the galaxy.
We haven't begun galactic exploration yet. We haven't even gotten out of our solar system. Why does life on other planets have to a) be light-years ahead of us in technology and b) have to come and find us. IF there was a life form that was traversing the universe, do you know what the odds are that they would have visited Earth? In the last 30,000 years?
You'd think that even if ancient astronauts had found Earth, we would have uncovered at least SOME sort of artifact. After all, playing the probabilities, if one civilization found us, it would be overwhelmingly likely that many, many others would be able to, and would. So far we've got nothing.
Heh. After all, it is all about US. *sigh* Do you even know what probability is? Do you know how many other planets there are out there? Do you know what it takes to not only traverse the galaxy, but the universe? (hint: you don't)
Re:well. (Score:2)
Re:well. (Score:2)
There might be millions of planets who are just hunters or have even started farming but none that has gotten to the industrial revolution.
The improvemnts in technology in the last 50 years are remarkable. Maybe we are the ones who's are leading the pack.
Or it may be so that it exist many thousands that are just 100 years ahead of us but all are spread at least 1000 ly from each other so no one will know each other for the next 900 years....
Space is very big and it takes time for the signals to travel from other civilisations.
List of Certainties ... (Score:2, Funny)
All right, so now it's official:
Did I leave anything out?
ummm yes (Score:3, Funny)
5 Slashdot misspellings on the front page tomorrow.
The more I read about this stuff (Score:2, Insightful)
And we most certainly don't know enough about the universe in order to make any kind of meaningfull scientific speculation on the subject. I mean seriously, we'd only just barely able to see planets outside this solar system.
We anthropomorphize more than we think (Score:4, Insightful)
Perhaps there is, but I can't imagine limiting ourselves to looking for multicellular, carbon-based, or RNA-based life, or for that matter any form of life patterned upon that on Earth. It seems to me astronomically more likely that highly organized or self-conscious matter found elsewhere would not be recognizable to us as what we would call "life".
I have slowed down my participation in the SETI@home project because I have become increasingly skeptical that other life forms would happen to care enough about radio frequency communications to build a transmitter. I consider it at least equally likely that extraterrestrial life forms are more interested in gazing at their own navels than evolving the means for the complex physical arrangements of materials necessary for instrumentalities designed to emit radio signals.
The yearning to communicate with other beings is both honored as a deeply "human" characteristic, and asserted as a likely goal of extraterrestrial life, but I think we have to choose one or the other, and get realistic about the chances of finding other societies sufficiently similar to us that we could detect each other.
Re:We anthropomorphize more than we think (Score:2)
If one in a million galaxies has planetary systems... and one out of a million planetary systems has a planet that 'could' support life and if one in a TRILLION of those spawned life, and if one in a TRILLION of those spawned something that we could recognize as alive and then one in a million of those became intelligent and then one in a million of those decided to emit radio signals, there would still be an infinate number of them spread througout the universe.
Granted, they might be pretty far apart... but it would be silly of us not to be listening.
Looking at it this way, intelligent life IS out there, it's just probably too remote to ever be seen or found or travelled to or even recognized.
Re:We anthropomorphize more than we think (Score:2)
As a rough estimate:
1 trillion (10^12) or less galaxies in the universe.
1 trillion (10^12) or less stars per galaxy.
10^24 stars total in the universe. Probably less.
That isn't quite room for an infinite number of technological civilizations, but it could hold quite a few.
Being generous, and dropping your first search term, if one in a million planetary systems (10^6) has a planet with life support, and one in a trillion (10^12) spawned life, and one in 10^12 had something we recognized as life, and one in 10^6 became intelligent and emitted radio signals (again, being generous and dropping your last term), then we're all alone most likely, because you've come up to one in 10^36, and that's dropping another 10^18th in your claim.
On the other hand, IMO, the odds are much better. I would just guess that most advanced races just get depressed about the whole long term entropy problem and commit suicide long before bothering to talk to us.
Re:We anthropomorphize more than we think (Score:2)
Re:We anthropomorphize more than we think (Score:2)
How is it then, that when we look around out there we see a couple of hundred billion stars (that's in our galaxy alone) shining away, all cheerfully following a predictable life path of stellar evolution? Thanks to the fundamental physical constraints of the universe, once collected in massive quantities, Hydrogen happens to make an ideal nuclear fuel. Its not completely impossible for a star to be 'burning' something other than Hydrogen (Red giants Fuse every element up to Iron in their old rage), but no star is likely to some into existence in such a state.
The point I'm having difficulty making is that -due to the physical properties of the universe- carbon based, multicellular, and even RNA equipped lifeforms are bound to be more likely than anything else, as these are the most efficient and simple paths to life.
I would hazard to guess that some of the higher order items like intelligence and communication and societal interaction would be far more likely to be completely unrecognizable and 'alien'. Chances are that their are many more potential paths to those states than there are to the state of life itself.
Which I suppose would imply that life is capable of a further order of 'creation' than physics alone is, even though physical law itself is the same foundation which allows for life to be exist. It all makes one's head spin. But in a good way
Timing (Score:5, Informative)
1) Life evolved on Earth pretty much as soon as conditions were stable enough to allow it. This suggests that bacterial life is highly likely.
2) It took at least hundreds of millions of years to develop Eukariotic life (big cells with a nucleus, such as we are made of, as opposed to bacteria.) This means that this step might be rare.
3) It took about 3 billion years to evolve differentiated multicellular life. This means that this step could be exceedingly rare.
4) Multicellular life evolved into a vast array of designs in a just a few million years (the 'Cambrian explosion'.) This means that once multicellular life starts, it will quickly produce complex forms.
5) From the Cambrian explosion to us is something like 500 million years. This is an intermediate time scale that makes it hard to judge how likely intelligent life is.
Disclaimer: I'm not 100% sure of some of the timescales above. It is all from memory.
Disclaimer 2: The Edicara fauna complicate the picture above on the origin of multicellular life, depending on how you interpret them.
Disclaimer 3: All the above is merely probabilistic. E.g. if the evolution of bacterial life is very rare, there is still a 5% chance that it will have occurred during the first 5% of the available time. Therefore we can't strongly exclude the possiblity that the evolution of bacterial life is hard.
the real question is (Score:4, Interesting)
Indeed... (Score:2)
Either that, or they could just have a "Prime Directive" law of their own, which would also make sense. When considering ET contact theorems, who says that the aliens in question actually want to talk to us?
Two schools of thought. (Score:5, Insightful)
There's the thought that its almost an absolute certainty that intellegent life has evolved elsewhere, and probably in vast numbers of individual civilizations.
On the other hand, the theory goes that within a few hundred years, we'll have the ability to (and therefore probably will) send generation ships to other solar systems. If we are to assume that 500 years after each colony is settled, it launches its own generation ship to the next solar system, the entire galaxy could be colonized in a matter of a few million years. This is of course assuming that most of the colonies don't manage to kill themselves off.
The point being, since a few million years is a cosmic blink of the eye, if any intellegent life DID exist, either it should be everywhere already, or all previous incarnations have wiped themselves out before they've had a chance to travel beyond their home world. Either that, or they're leaving us alone. After all, we ARE rather far away from anything. Its possible that a 4.3 lightyear stretch is too far to consider useful. And its also possible that we're the result of such a colonization project and everyone forgot about it, or were dumped here without knowing to begin with. Or maybe they knew and simply never passed it on. Its not like a lot of folklore has lasted for 30K years.
So, to recap this rant. Assuming there IS intellegent life, its already everywhere it wants to be, and either we're a part of it, or it's decided to completely leave us alone.
-Restil
Re:Two schools of thought. (Score:3, Insightful)
I don't think this is really something to put much stock in, considering the fossil record. Given the evidence that seems to support the idea that our species' evolution has taken millions of years from proto-hominid to today, there's not a lot of room for the idea that we are a lost colony.
Even if someone did settle this planet millions of years ago, something quite catastrophic would have had to happen in order to wipe out any fossil record of more advanced creatures than what we have seen so far. Which means we'd not be real descendants of theirs, anyway.
Re:Two schools of thought. (Score:2, Insightful)
The reason we think life elsewhere exists is because there is so much space that even if the odds on a planet producing intelligent life were 10^trillion against, there would be still be trillions of intelligent societies.
When you start to play with the odds, the distances to such life start to change. Better the odds, the closer are the planets that produce life. Worse odds means planets are farther away. The fact that other life forms haven't found us already leads me to believe that they are REALLY far away and never will contact us.
All intelligent life may begin to spread across the universe, but even at near light speed, it's entirely possible that the sphere encompassing their spread will never intersect any others. There is, afterall, a lot of space out there.
Re:Two schools of thought. (Score:2)
Then again, we could be the product of our own planet's evolutionary path combined with some insight from a space-faring race. This could explain the sorts of things we see when examining ancient Egyptian hieroglyphs.
Of course, both Drake's equation and the above are mere speculation, so anything is possible.
Re:Two schools of thought. (Score:2)
Two million years ago the planet of Golgafrincham loaded all of its useless members of society (advertising execs, hairdressers, telephone sanitizers etc) into a big space ship and fired it at Earth. The survivors of the crash supplanted the indigenous proto-intelligent mammals and became what is now the human race. The rest of the Golgsfrinchams died out tragically from a disease caught from dirty telephones.
I know it's tru, I read it in a book.
Re:Two schools of thought. (Score:2)
yeah... we're probably the decendents of telephone sanitizers and hair stylists.
Matrioshka Brains (Score:2)
So why's there no tragedy of the commons with these brains? They're advanced remember; we're just ants in comparison. :-) Just like how the richer/smarter nations on Earth tend to have lower population growth, so too might the MBs have achieved a virtual zero population growth zen.
Anyway, give Bradbury's paper a read, but fair warning: it might be a bit harder to suspend your disbelief when it comes to far-future hard sci-fi with conventional humans at the helm (Star Trek doesn't count). It's only human to anthropomorphize the future I guess...
--
Re:Two schools of thought. (Score:2)
Re:Two schools of thought. (Score:2)
That smells almost (not quite, but almost) as bad as creationism. If we're a colony, then the colonization would have had to have happened, much longer than just 30k years ago. More like two or three billion. The fossil and genetic evidence is just too strong.
Yeah, but what *kind* of life? (Score:3, Insightful)
Personally, I find it hard to get worked up about ET algae or whatever. I mean, it's a good thing in terms of implications for habitability of other worlds, terraforming, etc. But every time someone trots out an argument about how easy it is for life to arise in the universe, people assume that once you have life at all, you have intelligent life.
If life has arisen independently on Earth multiple times, how many times has it produced humans? And by this I mean, how many times did humans evolve, from scratch, our of distinct gene pools? I would have a hard time believing any answer greater than 1 (or less than 1, for that matter). So the more times life has formed and *not* evolved into sentience, the worse the odds are that it will have done so in other environments.
And even if sentient life has evolved on some reasonably nearby planet, what are the odds that we'll inhabit the same slice of time as them? Human beings have been a technological species for an infinitesimal time slice compared to the age of the galaxy, and at the rate we're going that time slice may not last much longer. If this is representative of sentient species in general, it would be very rare for two species to chance upon the necessary coincidence of space and time to actually meet each other. Sad but true.
Possible Fermi Paradox Solution (Score:3, Interesting)
We make a lot of assumptions (Score:2, Interesting)
There is lots of intellegent life! (Score:3, Funny)
The Prime Directive (Score:2, Interesting)
It seems logical, that any intelligent alien life, which came across us, would take note, that we are moving along quite quickly with our technology, and who are they to come in and say "You've got it all wrong!" Leave us be, and wait for us to catch up. If these aliens are there, they're simply employing a trait my father taught me years ago.
Give a man a fish, you've fed him for a day. Teach a man to fish, you've fed him for life.
V - the miniseries and Stephen Gould (Score:3, Interesting)
I recently rewatched "V - the series" and "V - the final battle". For those few here that haven't seen it, a bunch of seemingly humanoid aliens come to earth. However, these aliens end up being lizards who wear human skin to disguise themselves. A group of partisans realize the intent behind these aliens (to steal our water and use us for food).
One of the partisans makes what I consider a pretty good point (and makes this whole post on-topic). He notions the idea that unlike Earth, where some sort of disaster (meteor) wipes out many of the reptile species, the alien planet had no such disruption and the reptiles were free to evolve into sentient human-like beings.
Perhaps this is far-fetched. However, it is possible given our current idea of evolution. Why couldn't reptiles evolve into conscious beings? I'm not very knowledgable about the physiology of the human brain, but I do remember that temperature may have been a big factor in our evolution. The again, the word may implies that no one really knows exactly how evolution occured, and until we do I would say it is possible that reptiles may very well have been a predominent life on this planet if not for the meteor or whatever that wiped out all the dinosaurs.
Re:V - the miniseries and Stephen Gould (Score:2)
B) Any multicellular lifeform (including reptiles, dinosaurs, trees, mammals, etc etc) could POTENTIALLY evolve intelligence, but intelligence is a VERY steep/complicated peak of the genetic 'design space' that represents phenotypic possibility. From some areas of the design space (including those that are currently occupied by many species) it may be nigh impossible to make the jump to the base of such a peak and begin the climb. In other words, if you don't have things like endothermy (warm-bloodedness), binocular vision, quick reproduction cycle, relatively large mass, manipulating limbs, etc, etc, then your chances of developing sapience are that much more astronomical. The evidence lies all around us. With the exception of manipulators (and that is a big chicken & egg issue in and of itself), most mammals (for example) are fundamentally similar to us. But so far, humans seem to be the only really smart species of mammal. Having all the necessary environmental conditions and the genetic potential requirements all aligned perfectly for intelligence to even have a chance, is quite unlikely.
C) Think about this: perhaps we have already started up the wrong slope, and the limits of our brand of intelligence are far less than some other unaccessible (from our current location) area of design space. All those abundant aliens might just consider us mere animals too stupid to trifle with.
Old Argument + Same Logic = Same Conclusion (Score:2, Insightful)
The Earth radiates like a small star in the radio region, from our civilization's emissions. Yet we don't hear a peep of anything like that out of the rest of the universe, and there's no obvious evidence of stellar engineering to be seen either. Where are other forms of intelligent, information-exchanging, perhaps macro-engineering life? Well, it could be they aren't macro-engineers, or that they don't pass information like we expect them to.
But it could also be that there isn't any other life at all, or just low-level forms that we won't be talking to.
We only have one assured point of data to answer the Life question, and that's not good enough. One point doesn't "trend"; it has an infinite number of slopes; you can fit any curve to it. You can hardly expect to win your case for universal life without evidence of detecting anything outside of the Earth. Even other planets in the same system show no evidence of engineering or biochemical activity, and we've been looking at them for decades with some pretty good instruments.
We must keep looking, sure, but the evidence is pretty well on the side of a lifeless galaxy. Be scientists for once, and ditch that superstitious need for alien races and galactic empires. The facts are overwhelmingly against alien life, and until we expand our methods of searching, that's how we must judge it if we are to pay any due respect to logic.
On the hope side of things, our methods and assumptions can change with more data. For instance, it was taken for granted (although well-enough thought out) that if aliens existed, biochemistries between two such races would almost always be dissimilar. One race might settle on carbon, oxygen and sunlight, and another on silicon, hydrogen and geothermal energy. But recent theories and observations suggest that cosmic gas clouds harbor molecules that can start biochemistry upon planets. Since such clouds are large, it could be that this seeding process could produce similar biochemisty across different star systems. Hence, across the lightyears, biochemically-similar lifeforms might be able to arise if the seeding process has the potential we theorize. So the basic philosophy about alien differences has changed
Myself, personally, I figure we will need Jodie Foster {tm} to take up radio astronomy before we get the signals we are looking for.
Re:Old Argument + Same Logic = Same Conclusion (Score:2)
(There is a relatively small set of controlled situations where it is reasonable to claim certain things do not exist within the universe of the experiment based on the details of the observeration excluding the possibility of the existence of thing being proved to not exist within the confines of the experiment.)
That said, we do have several data points of planets that do not currently appear to us to harbor life. So it is fair to say that our present stage of knowledge, there do not appear to be any other intelligent forms of life in the universe.
Yet we also need to acknowledge the limits of this statement and admit that the state of our knowledge may be the limiting factor and not the presence of other intelligent life forms.
Two Points (Score:2, Informative)
Best - and most chilling - explanation I've seen (Score:3, Interesting)
Is in Toolmaker Koan [amazon.com]. Lousy book, interesting premise. The premise is that progress comes through conflict, and that any society with the social drive to achieve the technology necessary for space travel is - axiomatically - so conflicted that it always bombs itself back to the stone age.
It's hard to argue against. We haven't destroyed ourselves - yet - but then again, we haven't achieved space travel either. I don't count holding our breath while we dash out, touch the moon, and dash back. That's proof of concept. When we get a self sufficient and growing colony on another planet, get back to me.
Fermi Paradox Explainations (Score:2)
One of the standard arguments against the existance of ETI are 'von-Neuman' probes - self reproducing probes that go to a star system, use local resources to make more of themselves, then head off to other systems. Repeat until you've explored the whole galaxy. This can take as little as 15 million years. The absence of von Neuman probes in the solar system was used by Frank Tipler to argue against the existence of ETI.
A simple change to this idea leads to 'Beserkers' - von Neuman probes that don't just look for life, but hunt it out and destroy it, to remove competition for their builders. This idea was originally described in Fred Saberhagen's Berserker books, and something similar comes up in Greg Bear's Forge of God and Anvil of Stars, Alistair Reynold's Revelation Space and other recent work, and elsewhere. This also could explain the failure of SETI to detect radio signals - if you make yourself obvious, you get wiped out.
An alternative to this is that its not the probes that kill you, but colonising aliens, who use up all the resources in a part of the galaxy and then expire, making way for a fallow period and then another round of colonisation. Stephen Baxter's Space addresses this idea.
The basic message of these theories is that the galaxy may be like a quiet forest, but its not quiet because there's nothing there, its quiet because there are wolves in the forest.
And that's quite scary...
Human-like intelligence on this planet... (Score:2, Interesting)
Intelligent life has clearly evolved many times on earth, from dinosaurs to dolphins, octopi to owls.
Is there any strong evidence that no technological intelligence ever evolved on earth before America was born (irony)? I mean before humans came along?
If we all died tomorrow in an asteroid blast, what evidence would there be of our existence in a mere million years?
There was good article on this in New Scientist once which concluded the answer was 'little'.
Just a weird thought.
Don't forget - (Score:2)
Drake has one data point in his favor - us. We're here, and are the very sort of intelligent-life-that-arose-from-the-muck he's talking about.
If the conditions were right anywhere on this planet for our kind of biology to take hold and flourish, then I can believe that conditions elsewhere will click for either the same sort of biology we have, or a different biology based on other resources and processes.
The Drake Equation (Score:2)
The equation itself is as follows (as explained at the SETI Institute [seti-inst.edu]):
Where,You can check out Drake Equation calculators at MSNBC [msnbc.com] or at PBS's Life Beyond Earth [pbs.org] site. And for a little more reading, you might want to check out Is Anyone Out There?: The Scientific Search for Extraterrestrial Intelligence [amazon.com] by Drake himself.
Hopefully that helps.
The Rare Earth Equation (Score:2)
N* X fp X fpm X ne X ng X fi X fc X fl X fm X fj X fme = N
Where:
N* = Stars in the Milky Way Galaxy
fp = fraction of stars with planets
fpm = fraction of metal-rich planets
ne = planets in a star's habitable zone
ng = stars in a galactic habitable zone
fi = fraction of habitable planets where life does arrive
fc = fraction of habitable planets where complex metazoans arise
fl = percentage of lifetime of a planet that is marked by the presence of complex metazoans
fm = fraction of planets with a large moon
fj = fraction of solar systems with jupiter-sized planets
fme = fraction of planets with a critically low number of mass extinction events.
A few quick calculations... (Score:3, Informative)
show that we've 'reached' only about 5000 star systems by radio.
The first radio transmission with any power occurred on Dec 12, 1901 (the first trans-atlantic radio signal by Marconi).
According to the Nasa Near Stars Database [nasa.gov], there are 2633 stars within 81.5 ly. Assuming constant stellar density, extrapolation to 101 ly gives 5011 stars.
According to this site [cornell.edu], there are roughly 100 billion stars in our galaxy. That amounts to 0.000005011% of the stars in the galaxy. Not an impressive figure.
One simple proof: find life on Mars (Score:2)
If we can prove that microbes did exist on Mars in the past, then this does prove that life does have a chance to exist on other Earth-like planets orbiting other stars even in our own galaxy.
Why life on Earth arose only once? (Score:2, Interesting)
All evidence points that life here on Earth evolved, meaning each lifeform is derived from a previous lifeform. Considering that together with the fact that cellular life (all known life on Earth) multiplies by cell division, it most likely all the life on Earth, plant and animal, is the same old cell split in half googlezillion times.
So in four billion years, only one viable cell was produced (or one viable batch of identical cells). I would divide the number of viable planets anybody comes up with that 4 billion which are the yearlong chances life was to given to arise on Earth a second time and didn't take it.
Chances of intelligence (Score:2)
Compass Needle and Cell Development (Score:2)
of a magnet-needle on the Earth's surface in such a way as to try to
explain these movements solely out of what can be observed within the
space occupied by the needle. The movements of the magnet-needle are, as
you know, brought into connection with the magnetism of the Earth. We
connect the momentary direction of the needle with the direction of the
Earth's magnetism, that is, with the line of direction which can be
drawn between the north and south magnetic poles of the Earth. When it
is a question of explaining the phenomena presented by the magnetic
needle, we go out of the region of the needle itself and try to enter,
with the facts that have been collected towards an explanation, into the
totality which alone affords the opportunity to explain phenomena, the
manifestations of which belong to this totality. This rule of method is
certainly observed in regard to some phenomena, - to those, I should
say, the significance of which is fairly obvious. But it is not observed
when it is a question of explaining and understanding more complicated
phenomena.
Just as it is impossible to explain the phenomena of the magnetic needle
from the needle itself, it is equally and fundamentally impossible to
explain the phenomena relating to the organism from out of the organism
itself, or from connections which do not belong to a totality, to a
whole. And just for this reason, because there is so little inclination
to reach the realm of totalities in order to find explanations, we
arrive at those results put forward by the modern scientific method in
which the wider connections are almost entirely left out of the picture.
This method encloses the phenomena, whatever they may be, within the
field of vision of the microscope; while the celestial phenomena are
restricted to what is observable externally, with the help of
instruments. In seeking for explanations, no attempt is made to consider
the necessity of reaching out to the surrounding totality within which a
phenomenon is localised...
(Rudolf Steiner, Lecture Lecture X, January 10th, 1921)
http://home.earthlink.net/~johnrpenner/Articles/E
--
Suppose someone looks at the needle of a compass, finds it pointing from
South to North, from North to South, and then decides that the forces
that set the needle in the North-South direction lie in the needle
itself. He would certainly not be considered a physicist today. A
physicist brings the needle of the compass into connection with what is
called earthly magnetism. No matter what theories people evolve, it is
simply impossible to attribute the direction of the needle to forces
lying within the needle itself. It must be brought into relation with
the universe.
In studying organic life today, the relationship of the organic to the
universe is usually regarded as quite secondary. But suppose it were
indeed true that merely on account of their different positions the
liver and the brain are actually related quite differently to universal
forces outside the human being. In that case we could never arrive at an
explanation of the human being by way of pure empiricism. An explanation
is possible only if we are able to say what part the whole universe
plays in molding the brain and the liver, in the same sense as the earth
plays its part in the direction taken by the needle in the compass.
Suppose we are tracing back the stream of heredity. We begin with the
ancestors, pass on to the present generation, and then to the offspring,
both in the case of animals and of human beings. We take into account
what we find -- as naturally we must -- but we reckon merely with
processes observed to lie immediately within the human being. It hardly
ever occurs to us to ask whether under certain conditions in the human
organism it is possible for universal forces to work in the most varied
ways upon the fertilized germ. Nor do we ask: Is it perhaps impossible
to explain the formation of the fertilized germ cell if we remain within
the confines of the human being himself? Must we not relate this germ
cell to the whole universe?
In orthodox science today, the forces that work in from the universe are
considered secondary. To a certain limited extent they are taken into
consideration, but they are always secondary. And now you may say: "Yes,
but modern science leads us to a point where such questions no longer
arise. It is antiquated to relate the human organs to the universe!" In
the way in which this is often done, it is antiquated, but the fact that
generally such questions do not arise today is due entirely to our
scientific education. Our education in science confines us to this
purely sense-oriented empirical mode of research, and we never come to
the point of raising questions such as I have posed hypothetically by
way of introduction. But the extent to which man is able to advance in
knowledge and action in every sphere of life depends upon raising
questions. Where questions never arise, a person is living in a kind of
scientific fog. Such an individual is himself dimming his free outlook
upon reality, and it is only when things no longer fit into his scheme
of thought that he begins to realize the limitations of his conceptions.
http://wn.elib.com/Steiner/Medicine/19221026p01.h
--
Rights (Score:2)
Re:ET Life (Score:2, Insightful)
Especially regarding the probability that life will start in a puddle... Or in some wet clay, just as well... but taking puddles as an example:
Take a square mile of earth. Picture a kind of primordial earth, the surface seething with puddles. Maybe, say, one square foot of puddle for every four square foot of earth. That's
6,969,600 puddles per square mile. There are 197,000,000 square miles on earth; assume 1/10 of these are land, so multiply 6.9 million by 1.97 million: 13,730,112,000,000 puddles. Oh, then multiply that by 365 billion or so days, to yield the number of daily heating/cooling cycles provided by the rising and setting of the sun. That's 5,011,490,880,000,000,000,000,000, right? So maybe I've overestimated the surface area, or the number of viable puddles. OK, divide that by 10 to the third or fourth; it's still a pretty darn big number.
Next time some Creationist lectures you about how improbable it is that life started in a puddle, be sure to multiply whatever probability they provide by that number.
Of course there's that detail about cells, and multiple cells, and the "sudden" leap to intelligence (forgetting a few billion years here and there). Well, that would require... evolution! But then, this is starting to look like a troll, and I didn't mean it that way.
Re:ET Life (Score:2, Interesting)
"To claim life evolved is to demand a miracle. The simplest conceivable form of single-celled life should have at least 600 different protein molecules. The mathematical probabilitya that only one typical protein could form by chance arrangements of amino acid sequences is far less than 1 in 10^450. To appreciate the magnitude of 10^450, realize that the visible universe is about 10^28 inches in diameter.
From another perspective, suppose we packed the entire visible universe with a "simple" form of life, such as bacteria. Next, we broke all their chemical bonds, mixed all atoms, then let them form new links. If this were repeated a billion times a second for 20 billion years under the most favorable temperature and pressure conditions throughout the visible universe, would one bacterium of any type reemerge? The oddsb are much less than one chance in 10^99,999,999,873. Your odds of drawing at random one preselected atom out of a universe packed with atoms is about one chance in 10^112--much better. "
http://www.creationscience.com/onlinebook/LifeS
Re:ET Life (Score:2)
Like most creationists, you assume that atoms form molecules completely randomly. However, this is most definitely not the case. Basic organic chemistry, the seeds of life, has been seen throughout the cosmos - vast clouds of acetic acid, alcohol, and of course water vapor have been detected in outer space. These don't form randomly; they are an inevitable result of the atomic structures of the basic elements.
More complex things like amino acids also appear to be readily formed when their constituents are put together and energy is added. And, the recent synthetic polio virus experiment seems to indicate that very simple life forms just naturally fall into place. If atoms truly arranged themselves randomly, the experimenters would not have gotten a complete functioning virus.
The "tornado in a junkyard assembling a 747" argument is one tht creationists pop up quite often, but it simply doesn't hold water. All the parts of the 747 of life seem to fit together only in a few ways, and automatically snap together correctly when two parts came close to each other. Correct your analogy for this fact, and remember that there are trillions of trillions of junkyards and trillions of trillions of tornadoes. Life might or might not be common in the cosmos, but it's not the impossible event creationists make it out to be.
Besides, to me, the idea of a God who intricately designed all these individual parts and set up the parameters and laws of the universe in such a way that life was inevitable, is far more awe-inspiring than the idea of God just saying "poof" and the universe popping up in six days. Maxwell's electromagnetic field equations seem a far cry more stunning testament to a Creator than a simple "let there be light". Don't constrain God and His Creation to the simplistic fables of people thousands of years ago.
Re:ET Life (Score:2)
The Rare Earth Hypothesis that they are arguing about looks at those assumptions a bit more critically. It does not assume that there is no other life like ours out there but that it is VERY rare. That the life-friendly atmosphere and climate our planet enjoys is the result of a fairly large number of low-probablity chances.
The authors contend that on our planet at least life is dependent on being a certain distance from the center of the galaxy (too much radiation) but not on the outer edge (too little metal for a planet the right size to form). That cuts down significantly on the number of stars in our galaxy that can support life. We also need an unusually large moon (to stabilise tilt, create tides). We need plate tectonics (for a host of reasons) which also means the planet has to be a certain size and have a particular make-up and peculiar history.
After meeting all these conditions your potential planet with it's evolving life must avoid having that life wiped out by a mass extinction event. It helps to have a Jupiter sized planet to "clean up" all those comets, asteroids, planetoids etc. that would otherwise bombard your planet from time to time, periodically vaporising the oceans. But if that Jupiter is too close, or in an eliptical orbit (as all the extrasolar "jupiters" we have so far found orbiting other stars) it's gravitational effect will either drive your earthlike planet into the star (not healthful for life) or knock it right out of the star system (also not healthful for life).
Now your very rare earth like planet must simply avoid some bad luck, nearby magnetars, supernovas etc., getting hit by the chance comet that your friendly jupiter didn't clean up for you. etc.
Certainly starting with a large enough sample even these very stringent, and unlikely requirements will be met from time to time. But they will be rare and spaced far apart. Out of the billions of stars in our galaxy only a handful (hundreds, maybe only dozens) will meet those conditions, not the millions of advanced civilisations originally suggested by Sagan and Drake.
Re:Occam's Razor (Score:2, Informative)
Gravity is described as f = m(1)m(2)G/r^2. Einstein's theory of relativity is described as E = mc^2. F=ma, D = 1/2at^2 + vt + d(0), PV = nRT etc. etc... All seemingly complicated things described by very simple formulas. The vast majority of phenomena in physics are described by relatively simple equations. (major exceptions being any form of turbulence or a result of turbulence)
Then again, Occam's Razor doesn't apply very well to life sciences, which is what this is about.
Re: Occam's Razor (Score:2)
> Occam's Razor, that 'The simplest answer is most often the correct one.' has no actual logical value behind it.
The value of Ockham's Razor isn't "logical". The value of Ockham's Razor is that it keeps special pleading from getting a free pass.
Re:focus on what's here (Score:2, Funny)
That's why my CPU utilization is always 100%!
Ob OnTopic Tie-In: Because I'll get cancer long before you'll chat with aliens.
Re:Something that's rarely brought up (Score:2)