Sunday, November 25, 2012

Are We Alone in the Cosmos, cursed by Fermi's Paradox?

And now the news from Alpha Centauri

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

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

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

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

(See a collection of articles and speculations about the Search for Extraterrestrial Intelligence (SETI).)

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

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

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

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

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

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

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

In fact, this tradition goes back much farther, to wanderers' tales like Journey to the West and the Odyssey. The expansion of our horizons of interest may be among the most human of all activities, as we stretch our gaze and curiosity beyond the mere present, the mere town, nation or even planet.  If we ever do encounter the alien, it can be hoped that the vast literature of science fiction gedankenexperiments (thought experiments) about contact will be consulted by our wisest sages, who will be amazed and enlightened by the vast range of possibilities we humans have already imagined.

== The Essential Questions About Alien Life ==

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

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

... all of which I talk about in my most recent novel, EXISTENCE.   In ways that I hope readers find both fascinating and thrilling, embedded in an exciting, near-future plot  There's a new idea on almost every page.  And why not? I've been cataloguing the possibilities for what feels like eons.

== The Drake Equation ==

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

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

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

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

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

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

== The likelihood of life ==

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

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

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

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

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

== The Role of Sapience ==

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

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

A separate question, that I explore in EXISTENCE and also in my Uplift Series of novels – (now being re-released in the UK in beautiful omnibus editions by Orbit Books) -- is whether we should start to help other species burst through that glass ceiling and join us, as fully sapient fellow citizens of a much broader and more diverse Earthly culture.  The end result, that I portray in Startide Rising and The Uplift War (both won the Hugo Award for best novel), is a much richer and wiser civilization.

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

== The Minefield Ahead of Us ==

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

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

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

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

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

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

Perhaps the most painless and entertaining way to learn more is probably on the pages of my novel (I promise).  But I'll supply plenty of other links for those who relish our most precious human gift ---

-- The wonder of curiosity.  The insatiable thirst to know about what we know... and to speculate about what we don't and to explore this vast realm. A topic we all find fascinating... and as-yet we understand so poorly.

David Brin
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Anonymous said...

I'd think that life is bound to be widespread in the Universe, but distance in both time and space will probably eliminate the chance of us encountering intelligent lifeforms any time in the near future. I will say, however, that just because we can't hear their radio signals doesn't mean that no one is there. Such a form of communication could be barbaric in a civilization just a few hundred thousand years older than we are.Light could be used much more discreetly to communicate over great distances. Of course, for all I know, you might be a flying saucer dude yourself, Mr. Brin. Ha-Ha. Just Joking.

Boogeyman said...

Not all traps have to be filled with snakes. How many races might have willingly shut themselves away in a much more pleasant version of the Matrix? The real universe is messy and difficult. The attractions of living in a (near) perfect holo-deck world of your own creation, where you are a virtual god and every thing and diversion can be brought forth by wishing it, must be almost impossible to say no to.

Unknown said...

You guys are raising some of the classics! You might enjoy reading some of the detailed appraisals of all of that (and more) that I offer elsewhere.

David desJardins said...

We have to assume, until we have reason to think otherwise, that complex life must grow and evolve to intelligence on planets orbiting stable stars. Excuse me? Why do we have to assume that? In my opinion, common sense suggests that the probability of intelligent (or even multicellular) life is likely to be infinitesimal. That's what we should assume until someone produces reason to think otherwise.

Unknown said...

DdJ read the sentence again and take the other meaning of "must".

Stefan Jones said...

I just (finally!) finished reading the printed version of Existence and feel TOTALLY BURNED OUT on this subject! ;-)

A news story making the rounds last week reported on a study suggesting that star formation had all but ceased in the Milky Way.

I have a hair-brained idea on how a long-lived and forward-thinking civilization might deal with that . . .

Mike said...

It seems to me that the question isn't about the presence of life, or even intelligent life. But rather, the presence of intelligent life that can create technologies capable of signaling other worlds.

In our world this was made possible one important natural resource. Fossil fuels.

So you need a candidate world that has life for a billion years, and then creates conditions possible for intelligent life, and then that intelligent life has to discover fossil fuels, and then industrialize without killing itself or the world's environment.

We've had radio for about a century, and in that time we've almost destroyed civilization, and we're in the process of possibly doing it with global warming.

So over the 4 billion life of our planet, we've had about 1 century of radio emissions. Let's say, for the sake of argument, that we last about 100 centuries. That's only 1250 planets in our galaxy that might be currently in a phase for communicating (assuming 50 million exoplanets in the habitable zone. Let's further assume that only 10% of these are near enough to us to communicate.

That assumes 100% of all the other factors. It seems to me that industrialization process and its dependencies on the factors leading to fossil fuel creation are the governing factors in the drake equation.

The only unknown is how long technical civilizations last. If they last considerably longer than my 100k estimate, we should see more, less? Well then we've got other issues.


Tim H. said...

A society might not pursue technology for cultural reasons, or might be aquatic and unable to play with fire. A visiting warp ship might've inadvertently irradiated developing worlds. Or possibly, we won't hear anyone else until we can build outrageously large arrays off-planet.

David desJardins said...

Fossil fuels?? Come on. If we had no fossil fuels at all, our civilization would look virtually the same, we would just pollute less. We could make all the energy we want from solar power or from wind power or from fission or from geothermal sources or several other possibilities. Fossil fuels are a political problem because they are so easy and tempting to use. But, from a societal point of view, if we simply didn't have them the whole problem would disappear.

Acacia H. said...

I've gone on at length concerning this in the past, Dr. Brin. You are fully aware of my feelings on this. But in essence, I feel that there are specific factors that need to be kept in mind to allow for intelligent spacefaring species which would be rare when taken as a whole. One, which you discount, is the importance of a sizable moon to stabilize the axis tilt of the planet so that seasons remain fairly sedate over a long term.

Another is how a Super Earth would be viable for life... but would be the ultimate gravwell trap for the species and force them to remain within their atmospheric prison (and for that matter, a sufficiently dense atmosphere could conceal the presence of stars outside of their sun... and thus diminish any real interest in an "outside" to explore).

A third is the fact that insufficient landmass would make it difficult to expand and develop technology - superintelligent octopuses would be limited in not being able to forge metals and the like, for instance. And if the planet is coated by a layer of ice, then that shell becomes a ceiling from which they cannot escape in any event.

Stellar neighbors could also cause problems - a nova could irradiate a planet if it were in the wrong place at the wrong time. Life-bearing worlds would become increasingly rare the closer you come to the core of the galaxy due to the presence of so many larger stars which could explode and irradiate the region. Thus you're left looking at stars in arms of the galaxy like ours... or halo stars on the outreaches.

We lucked out. We're the first to make it this far in this region of the galaxy. Possibly in the entire galaxy.

Rob H.

David desJardins said...

Rob, you do know there are 300 billion stars just in our galaxy, right? And you think the problem is not the vast improbability of random amino acids bumping into each other and forming DNA along with all of the self-reproducing machinery, but the issue is that there aren't enough large moons in the galaxy? Seriously??

Acacia H. said...

What I'm saying is that when you factor in the stars that are best suited for habitable planets (red dwarfs have problems because they tend to flare a lot, which can irradiate a world before complex organisms even arise), the need for a world that's not too small to retain an atmosphere nor too big to trap life on its surface, with a stable orbit and stable axis tilt, in the life-bearing zone of a world, that develops an intelligent species that overcomes the glass ceiling other intelligent species other than humanity have not overcome, and then overcome self-destruction or cosmic accidents... and that 300 billion suddenly gets cut seriously down to a much much much smaller number.

David desJardins said...

I think you're underestimating how many times you can divide 300 billion by factors of 2 or 3 or 4 and still have it be a very big number.

On the other hand, if the probability of random chemicals self-assembling into a self-reproducing machine is 1 in 10^1000000, then that one thing by itself is plenty to explain why there's no (intelligent, complex, multicellular) life in the universe, but us. Occam's Razor, and all that.

Acacia H. said...

You're not dividing 300 billion stars. You're taking the fraction of that in which the star is stable enough to not risk irradiating the planet on a regular basis (ie, not too big or too small). From that, you then factor in the rest of the externalities and you end up with a remarkably SMALL number.

Mind you, I'm not talking about the existence of life. I'm not even talking about the existence of intelligent life. I'm talking about SPACEFARING life. If the life cannot move beyond simple tool use because it's an underwater species or even just can't leave its planet because of the gravwell or atmosphere, then it's not going to be a civilization we readily detect. Or care about.

The question is: why are there no advanced spacefaring civilizations. I'm stating that the factors leading up to a spacefaring civilization is far harsher than people are thinking. It's not that there's Berzerkers out there destroying life... or other cosmic boogeymen. It's that we're the first species in this region to actually step outside the boundaries of our world. We lucked out to get this far.

Rob H.

David desJardins said...

I guess, if somehow we discover that there's actually other complex life in the galaxy, then complicated explanations to resolve the Fermi "Paradox" will be necessary. But, until we have such evidence, the bog-simple explanation that there just isn't any other complex life, seems by far the most straightforward and reasonable.

David desJardins said...

P.S. "In this region" also isn't a very good answer, because it's pretty obvious that any intelligent species that advances to tool using can, in a relatively short period of time thereafter, build self-reproducing machines and transform its entire galaxy into whatever form it wants. If there were intelligent life in other galaxies, it would be obvious.

duncan cairncross said...

There was an article in New Scientist a while ago,

Life: is it inevitable or just a fluke?

Life may be very common - seems to have appeared as soon as the earth was cool enough,
Eukaryotes seems to have come a LOT later,
The article considered the dynamics of complex cells like ours and put forwards the idea that while prokaryotes may be very common Eukaryotes could be insanely rare

David Brin said...

Stefan so how'd you like it in paper form? gud buk?

Mike good point. Many other worlds may have developed good anaerobic digesting bacteria that failed to develop on Earth, allowing the plant matter to pile up and form hydrocarbons deep below.

DdJ fossil fuels let us bridge a huge gap. We STILL cannot make solar arrays or wind mills without burning lots of fossil fuels to make the panels and motors!

Robert, your list of reasons just don't strike me as being highly compulsory ones. I can see them being factors on maybe a 10% level. Except the water worlds thing, which I do mention a lot. Earth skates the innter edge of its goldilocks zone and that one might plausibly affect factors by an order of magnitude or two.

I lean towards Intelligence explanations. The glass ceiling shattered only once on Earth in 500 million years since metazoans got complex. But yeas, the previous 3.5 billion years was glacial at even starting with metazoans.

David desJardins said...

I totally agree that fossil fuels provided a big jump (albeit with a big cost). But, seriously, does anyone argue that if there weren't oil and coal and gas in the ground, we would have gotten to the 19th century and then technological progress would have just stopped forever? Come on. We'd just go down some different energy path. Maybe it would take a little longer, but then, we've got plenty of people (the vast majority of the world's population!) not really working or doing anything useful now, if we needed to develop more capacities to power our society we would just do it. It's hard to convince people to do without gasoline when it's so easy and cheap, but if no one had ever heard of the stuff, human beings would just shrug and come up with some other solution.

Jumper said...

Birth control is inimical to any life form, perhaps. Maybe that's the bottleneck. With birth control, though, wood power would suffice. Even for rockets. But wood power could lead to fission and fusion eventually.

Aren said...

A thought that crossed my mind and of which I don't know the physical feasibility – Do thick ice shields protect against random stellar bursts?

Essentially, what about planets or moons way beyond the goldilocks zone, covered in thick layers of ice, but still hot or at least warm on the inside. Mr. Brin called them roofed worlds, I think. Those worlds could reasonably contain life, right? Of course we can only assume and guess until we get a few or at least one data point on the subject. But, would these layers protect against the random bursts by stars that aren't very stable (but stable enough)? And not necessarily from the stars they're orbiting, but also by neighbouring stars.

I'm asking because I had an idea. Basic premise: Life is plentiful enough. But there's a sliding scale of the origin/cradle of life in star system based on its stellar activity and also proximity to the galactic core. I.e. the "outer" stars are settled by surface dwelling lifeforms (yet also roofed ecospheres occur) whereas the inner systems only contain life in roofed cases, with stellar bursts resetting or totally wiping out surface dwelling life.

Hence my question: Could ice of realistic proportions protect against such bursts, or not?

Acacia H. said...

Water is a very good method of protecting against cosmic radiation. One of the methods talked about for protecting astronauts is to have water act as a shield between the habitable part of the station or ship and the outer hull. The problem is, of course, the weight.

Now, if a few inches of water can protect against regular cosmic radiation... then a mile of ice can likely protect against radiation even in the galactic center.

Rob H.

Acacia H. said...

On a tangential note, Dr. Brin, I do have a couple questions concerning "Existence" - first, is there a listing of definitions for some of your words anywhere? The use of futurease is commonplace with science fiction, I must admit sometimes I'd like to know if what I suspect a term is in fact is what the author intended.

Second, I'm wondering about the underlined sections of the print compilation. Are these actual links for use with e-books? If not, why do they exist? Seeing that I'm not about to spend $15 for the e-book version when I can hopefully see the price drop once the paperback edition of "Existence" comes out (that and I feel $15 is too much for an e-book; publishers do not need worry about printing, paper, or distribution costs with e-books. I'd spend $10 for the book easily. But going over $10 and publishers aren't getting my e-commerce). (That said, if publishers had put out a joint-purchase deal where you buy the hardcover and for an extra $5 or $7 get the e-book as well, then they'd have gotten a number of sales that way.)

Rob H.

Acacia H. said...

And last... here's a prediction that I've not heard bandied about yet. Rather than Curiosity having discovered life or methane or the like, I'm going to predict that Curiosity detected liquid water just under the surface of the planet and that NASA is investigating a couple areas to verify the liquid water.

Rob H.

Paul451 said...

Rob H.,
If it was liquid water (or life, for that matter), it would have leaked by now (no pun intended). You couldn't keep something that big restricted to just the team.

Methane's also out because MSL's chem team has already announced a noticeable lack. Fossils would be visual not chemical, so it's the wrong team for that.

Subsurface ice? Which at MSL's latitude would be brilliant for a manned mission. (Or less "earthshaking", but along the same lines, a high level of extremely hydrated minerals, ie, 40-50% water by mass.)

Hmmm, how about literal Earth-shaking, MSL discovered a meteorite with an isotopic ratio similar to Earth's crust. Curiosity goes all the way to Mars, finds earth. (Pun very much intended.)

gregory byshenk said...

DdJ, it seems to me you underestimate just how hard it is to get to a technological civilization without fossil fuels.

As David notes, even now we use fossil fuels to provide the technology we use to harness solar and wind power. Certainly one can do some simple things with wind and solar (as people have been doing for a very long time), but things like refining ore are really hard without something like coal to provide the energy density. And a society needs to get past that point to reach the high-technology state that we are now at, where we can use our technology to better harness wind, solar, etc.

Acacia H. said...

People were using charcoal for forging for some time. While the energy use to create charcoal is fairly high, it is still doable and thus societies would be able to work with a number of metals - assuming of course that there are veins of metal in their planetary crust and that the metals didn't just sink to the core for the most part (it is believed that the impact that helped create the Moon also resulted in the mixture of a lot of iron into the crust and mantle... though to be honest we'd need to have a more thorough exploration of Venus to determine crustal composition of Earth-sized planets that did not suffer a massive collision like that which caused the Earth-Moon double planetary system).


I honestly think NASA would be better able to conceal data leaks about liquid water just under the planet's surface. After all, they aren't under an obligation to report hoaxes or incorrect data. Thus they wish to verify. And liquid water is far more likely to have been detected than microscopic fossils or the like. But we'll find out in another month or so, no doubt.

Rob H.

David desJardins said...

We use fossil fuels because it's easier, not because it's necessary. Can't you see the difference? Human society made no significant use of fossil fuels before, when, 1800? The entire course of human history up to that point would be the same if the planet had zero fossil fuels. If there were no fossil fuels, what would happen after that point? You seriously think that human civilization would stall at the 1800 level of development, forever?? Seriously??? We would just pursue the second-easiest form of energy, and eventually we would have enough of that to power everything we do. OK, maybe it would take an extra 100 years to get from 1800 technology to today. So what? It took billions of years to get to 1800 technology. What difference could the additional effort to develop a civilization-wide source of energy, possibly make?

Paul451 said...

Rob H.,
"we'd need to have a more thorough exploration of Venus to determine crustal composition of Earth-sized planets that did not suffer a massive collision"

That's assuming Venus didn't. It's a very odd world.

gregory byshenk said...

Robert, yes, one can do some basic forging with charcoal, but one is limited both in what one can do, and in the amount of wood available to what one can. Without access to coal, it is really hard to produce significant industry without running out of wood.

DdJ, coal has been used since antiquity, and saw significant use in England already in the 14th c. As the Wikipedia article History of Coal Mining (which I believe to be accurate in this area) notes, "However, by the middle of the 16th century supplies of wood were beginning to fail in Britain and the use of coal as a domestic fuel rapidly expanded."

That said, I have no idea whether "human civilization would stall at the 1800 level of development, forever". No doubt something would be different, but no one knows exactly how. But just asserting "We would just pursue the second-easiest form of energy" is facile. I don't think we know even now how we could jump-start high-tech civilization without fossil fuels. The "catch-22" is that you need high technology in order to recover high energy from solar, wind, etc., while you need high energy in order to get high technology.

Paul451 said...

David desJardins,
"Human society made no significant use of fossil fuels before, when, 1800"

In the pre-Roman middle east, there were wars fought over good sources of bitumen, it was so important.

Europe's emergence from the dark ages and ascendancy to world power correlates strongly with their rediscovery of the uses of local sources of fossil fuels.

There's no argument that our 7 billion people use more than their couple of hundred million. But that doesn't mean it wasn't important to development.

Besides, why the argument? If there's life, there's kerogen. If there's kerogen, there's going to be fossil fuels somewhere.

pindiespace said...

David, this one is one I think a lot about. I'm not sure the problem is up in the "civilizations destroy themselves" era. We can speculate, but we only have our own minds as a basis for analysis. One recent idea (John Smart) is that races disappear into their virtual realities in all cases as preferable to the real world (though Olaf Stapledon also covered that one in his 1930s novel "Star Maker").

The biggest hurdle, IMHO, is the origin of life itself, which is frequently assumed to be easy. The building blocks appear naturally. But we don't see the next level. The assumption of life is "easy" to mees seems very weak. The problem is that we have very little evidence that this is the case.

This has been an issue that I have been interested in since grad school at U Chicago, when I experimented with trying to keep enzymes functional in liquid ammonia. Over the years, I have become less optimistic, and feel that the origin of life, is the stumbling block.

Here's the problem: while intelligence might not be a Von-Neuman style computing system, life certainly is - code, data, and substrate are split neatly. You have code in DNA and RNA specifying the assembly of machines (enzymes) using a pick and place robot (ribosome). The origin of the code and its ability to drive assembly is the big problem - what pre-evolutionary, pre-Darwinian force would create an arbitrary code describing a process?

Despite the hoopla every few months in the press over "the creation of life in a test tube" (story titles since the 1960s on this topic) nobody has created life in the lab. We can take material from existing living organisms, and stitch them together, frankenstein-style, into a "new" organism (this is what Craig Venter did). But this isn't the same as evolving a coding system from building blocks.

There have been lots of theories on how a coding system might "bootstrap" itself - but no real experiments. There have been lots of attempts to evolve coding systems in the lab, e.g. RNA molecules catalyzing the synthesis of other RNA molecules. Every attempt I'm aware of quickly ground to a halt with a "frozen" collection of endpoint molecules, none of which looking like something alive. In other words, it's not acting like a code-based system, but a typical physical process going to an endpoint (like cloud formation).

This isn't the "rare earth" hypothesis popularized by Ward and Brownlee. Their version of the Drake Equation assumes that Earth-style conditions are required for the emergence of life. This is false, since there may be many other ways life might emerge (even Fred Hoyle's intelligent stellar clouds). The problem is not the molecules, but the probability of a coding system emerging "by accident" from said collection of molecules.

A pure information theory approach (where you calculate the probability of a specific sequence of information ending up in a molecule (Yockey) gives such low values that we shouldn't be here, even considering all the stars and galaxies in the visible universe. This is too pessimistic, since there must be many degenerate coding sequences specifying life. However, even assuming coding degeneracy, the number is still likely to be super-low.

The only plausible idea I've ever heard to lower the odds is Marty Sereno's "DNA and Language" theory (, which seeks to draw parallels between the origin of DNA coding and symbolic language in humans.

Even then, I'm not convinced. Once life is established, it seems very hardy. The trick is getting life at all. I wouldn't be surprised if our own origin of life was a ultra-freak accident that we see as likely owing to too much anthropic thiking

David desJardins said...

You're just vastly overestimating how hard these things are. It's an illustration of how some people don't do well at imagining things different than actually exist. You can generate huge amounts of energy just by burning biomass---if you cut the world's population by a factor of 2 or 3 or 4, and used most of the land for growing biomass rather than food, you can generate a large fraction of the energy we currently use in that single way. Crystalline silicon cells are rather energy-intensive to make, but you can make amorphous silicon panels with much less energy, we don't do much of that now mostly because energy is cheap. I could list 20 other ways to build a high-technology society without fossil fuels, without breaking a sweat. I can't predict which of them would be most successful, or whether something else would emerge that didn't make my list, but obviously one of them would be. The most important thing is that you look all around at the technology that was invented because of the circumstances that people face, and you don't see at all the technologies that were never invented because there was no demand for them. But on your alternative world without fossil fuels, they would be all over the place.

David desJardins said...

The trick is getting life at all. I wouldn't be surprised if our own origin of life was a ultra-freak accident that we see as likely owing to too much anthropic thiking.


gregory byshenk said...

DdJ, yes, there is energy in biomass, but it isn't dense or convenient. Consider your scenario and you must consider the question of transportation. To be able to transport that amount of fuel those kind of distances, you would need to already have the ability to produce large quantities of steel at an affordable price in order to build railroads, steam engines, ships, etc. One is not likely to be able to transport vast quantities of biomass over vast distances using animal power or wooden sailing ships.

I don't know what your "20 other ways" are, but your number one looks like a non-starter.

Does any of this mean that something couldn't have happened? Of course not. But just waving our hands and saying "it would have had to have happened somehow" isn't an answer.

David desJardins said...

DdJ, yes, there is energy in biomass, but it isn't dense or convenient.

Just listen to yourself. Not convenient? That misses the whole point. The aliens on that planet with no fossil fuels aren't going to sit around whining about how inconvenient it is that no one buried dense, convenient energy right underground for them to dig up. They are just going to get on with filling their needs in some other way. Converting biomass to electricity or denser, more convenient fuels is, in fact, very easy. It's limited in efficiency, but that's not at all the same thing as saying you can't do it. That society would use energy differently than we do---sure, it might not get around in internal combustion vehicles and drive 50 miles to and from the office each day---but in all essential regards it could do everything we do. And there are literally 20 other ways to accomplish exactly the same thing.

I try not to judge people on the internets, but you've got to be smarter than this. You seem like a bright guy with a huge mindblock in your ability to imagine any society even slightly different from our own.

What I'm thinking of right now is the Greg Byshenk on that other planet thinking about their own energy system and about how no other intelligent civilization could possibly have developed elsewhere in the universe because they probably wouldn't have the same kind of photosynthetic organisms, or the same convenient wave activity to draw energy from, or the same geothermal sources right near the surface, or any of fifty other things that their civilization might have happened to grow up around.

Acacia H. said...

Back in the times of Greece there were stories of using curved mirrors to burn ships on the horizon. While Mythbusters proved this to be a genuine myth... the use of curved mirrors to focus sunlight and provide intense heat at a localized point remains a valid method of generating very high temperatures. It could be something as simple as creating magnifying glasses and using the crude magnifying glasses to melt sand more effectively to create better-quality magnifying glasses... and on down the line. Eventually you have mirrors and magnifying glasses powerful enough to melt metals and start the forging processes. Yes, you need sunlight to do this... but it's still doable.

Rob H.

sociotard said...

And yet the Mythbusters showed that the mirror-burns-ship story is likely just a story.

Acacia H. said...

You didn't read what I said, did you. I stated that Mythbusters found the story to be a myth. The underlying aspect to it (using focused light for heating and burning) remains true despite that myth.

Library Ogre said...

I had never read the "space dust as bacteria" hypothesis before. That was beautiful.

Ian Gould said...

Not wood per se but wood gas and wood oil fueled a larger part of the industrial revolution than many peopel realize: that's lquidi and gas-phase fuel produced by the pyrolysis of wood.

New Scientists recently offered a new and depressing explanation for the Fermi Paradox (without reaiizing it).

The time it takes to actually master a scientific discipline to the point where you can contribute to advancing it, keeps increasing.

For example, the average age of Nobel laureates in Physics and Chemistry when they did the work that subsequently earend them their Prizes has increased over the past century from 30 to 38.

If we accept David's view that huge potential increases in human life expectancy aren't realistic and the ageing trend increases, then the period in which peopel have both the knowledge and the mental capacity to do orginal scientific work should decline - as the complexity of the challenges increases.

So it may be that there are, relatively speaking, many technologically advanced species in the galaxy - stuck at a level of technology not very advanced beyond our own.

Maybe even though an Alcubierre warp drive appears theoretically possible, it will take us thousands, tens of thousands or millions of years to actually build one.

shaun said...

If you ask me, the search for extraterrestrial life begins and ends with the phrase "Know Thyself".

Ian Gould said...

"DdJ, yes, there is energy in biomass, but it isn't dense or convenient. Consider your scenario and you must consider the question of transportation. To be able to transport that amount of fuel those kind of distances, you would need to already have the ability to produce large quantities of steel at an affordable price in order to build railroads, steam engines, ships, etc. One is not likely to be able to transport vast quantities of biomass over vast distances using animal power or wooden sailing ships."

Except that, that's pretty much what most societies did up until the 18th century.

The first industrial revolution - the one that started around 1750 was based largely on canal transportation and wind power.

A lack of cheap abundant fossil fuels would probably have retarded our progress by 50 or 100 years - which is largely insignificant on a galactic tismescale.

David Brin said...

Aren your scenario for roofed worlds is very convincing.

Robert & Greg & DdJ, Nobody is saying that a resilient and determined sapient species cannot continue moving forward and bridging the gap to solar/geo/wind electricity using charcoal alone. Indeed, science could still proceed moving forward, using charcoal.

But metals would remain as they were till say 1500 CE... relatively rare, precious and owned by elites, giving them huge advantages, leading to treinforcement of the pyramid-society failure mode.

Notice also that charcoal-making is a forest killer. Read Jared Diamond's COLLAPSE.

That gives you three fermi failure modes all deriving from low levels of fossil fuels... though a LATER fermi (global warming) that arises BECAUSE of fossil fuels! Hence DdJ there is no reason to be insulting or offended. Robert's reasoning was just fine.

Question, if most gaia worlds have more CO2 than Earth... because we skate the inner edge of our goldilocks zone... what would be the consequences?

Pindiespace thanks for the cogent defense of what I think to be a very unlikely Fermi. Temporal matters are persuasive. Life clearly needed acres of time to become metazoan (3.5 billion years)... and then more acres (500 millions) to go from metazoan to sapience. But life itself seems to appear almost as soon as the rocks cooled enough for seas to form.

Hoyle & Wickramasinghe speculated in my area, comets, about how recent supernovas might seed new comets with aluminum26 which they melts the interiors creating trillions of cubic-mile reactor vessels for that many separate organic chemistry experiments... hence life starts out there then falls here. See HEART OF THE COMET.

I am increasingly amazed how many different Earth species crowd against the glass ceiling of basic vocabulary and tool use. Arguably chimps and dolphins are a run higher... but only a rung. Something is very hard about intelligence... and we burst a thousand rungs farther than Darwin could ever have required of us, to be masters of the planet.

Ian link to that New Scientist article?

Unknown said...

I feel possibility of intelligent life is a pretty good one. The fact that we haven't heard from anyone isn't really a problem for me. How long have we been "transmitting"? A hundred years or so out of 14 billion? That's like saying whales don't exist while looking through an electron microscope.

I also don't have a problem with ET not contacting us. Can you imagine the pandemonium that would ensue if ET picked the US over China/Russia to communicate with? Hmmm...maybe that's why there is such a push for a one world government....

Not to mention, we are way too barbaric. We like to think we are civilized, but just listen to 5 minutes of any news cast anywhere and you'll realize we are anything but. What would be their motivation to speak and or visit with us other than zoology?

Maybe it's just like Star Trek...until we are capable of traveling between stars, we are not worthy. Makes perfect sense to me. Fortunately they don't have the need for primitive pets, or we would be in big trouble!

Jumper said...

Jared Diamond is why I mentioned birth control as a very useful method of husbanding energy. Overpopulation can cause all manner of doomsday scenarios. For examples, look around.

I do believe trains ran on firewood when far from coal supplies.

Making of Damascus steel was wood powered.

I like the ideas of wood extracts! Trucks running on turpentine...

There's always water power, too.

Jumper said...

Just for fun I propose the Mars mystery is the discovery of a strong signature of gold in one of the samples.

David Brin said...


Prakash said...

Mike and DdJ,

I agree with Mike and DB that fossil fuels were a huge factor. The economy looks completely different with fossil fuels. Just the amount of things that are possible with access to more metal and plastic is huge. I remember thinking, when I visited Holland, on why windmills were not pioneered by India or China. Innovation is difficult, coordination is difficult.

Without access to fossil fuels, one either has to rely on animal labour or human labour. With access to that, there is no incentive to develop energy sources. Also speaking from an ancient indian perspective, thinking about how to improve the labourers' lot would rarely have struck a brahmin lost in metaphysical speculation. I could be wrong, but it is something that is a logical possibility. Fossil fuels freed humanity to apply an incredible amount of unused brain power to scientific advancement, without hard labour having to be done. The universe could be full of feudal societies that never took the steps to the industrial revolution.

David desJardins said...

Without access to fossil fuels, one either has to rely on animal labour or human labour.

It's just not true. There are many other sources of energy, easily available to humans, any one of which can provide far more than the entire current energy consumption of human civilization.

why windmills were not pioneered by India or China.

Not that it matters here, but windmills existed in China before Europe.

David desJardins said...

But metals would remain as they were till say 1500 CE... relatively rare, precious and owned by elites, giving them huge advantages, leading to treinforcement of the pyramid-society failure mode.

I guess I don't understand what kind of "failure modes" you're talking about. It seems to me that once human beings develop cognitive abilities that they have, they inevitably have to reach our current level of technological development, sooner or later, unless wiped out by some unlikely global catastrophe first. Sure, there comes a time when civilizations might destroy themselves, but they can't destroy themselves before they develop the technology to destroy themselves. So if it takes longer or shorter period of time to develop that technology, it doesn't really matter, they all have to get there in the end.

duncan cairncross said...

I'm not sure about the density argument - I'm thinking about whale oil
A society that used very little fossil fuel used sailing ships to sail all around the world - to bring back whale oil

If there was no oil or coal there would be biological substitutes - and peak oil would occur early
But that would be transition to some form of farmed oil
Rape Seed??

gregory byshenk said...

DdJ, please note, as I already said, that I am -not- claiming that technological development would be impossible without fossil fuels.

I am arguing that one cannot simply hand-wave away the difficulties; without fossil fuels, the development of industrial/technological society is much, much, much harder. And the problem with evaluating whether it would be "too" hard is that we have only one "industrial revolution" to compare against, which makes it difficult to say anything useful even about the -chances- of success or failure.

Perhaps development would be unable to become self-sustaining, collapsing back to pre-existing levels. Perhaps, as David notes, technology would remain a toy of the ruling class. Perhaps ever-growing demand for "biomass" would lead to conflict and social collapse, or to ecological collapse.

Or perhaps not. My point is that we have no way of knowing one way or the other, and we cannot presume that some other solution would arise.

David Brin said...

"I guess I don't understand what kind of "failure modes" you're talking about. It seems to me that once human beings develop cognitive abilities that they have, they inevitably have to reach our current level of technological development, sooner or later,"

David you are making unwarranted assumptions. Most human cultures were highly conservative and the pyramidal shaped oligarchies. Someone give the link to where I recently discussed this.

I think you deeply misunderstand the potential for stagnation which was the norm in human affairs...

...during which ecological deterioration proceeds anyway, at lower tech! Vast deserts were spread by goat herders and salinified soild from irrigation. Have you ever looked at "fertile crescent" Iraq? Easter Island? Or read Jared Diamond's COLLAPSE?

Frankly, I expect many races to enter steady decline if they stagnate. Our rapid rise was lucky.

Ian Gould said...

I mentioned some of this before and should really develop my thoughts further:

One of the key results of the discovery of the Americas was the discovery of what were in effect, highly concentrated sources of embedded energy.

These were: the cod of the Great Banks, the otter, beaver and deer furs of the the north west fur trade and cheap sugar (both raw and in the form of rum).

A kilo of cod displaced probably 50-100 kiloes of grain fed to domestic livestock to produce an equivalent amount of meat.

A fur hat or jacket displaced probably a hectare of cotton or flax - and cheap winter clothing displaced both fuel consumption and additional food consumption.

While we think of sugar as a sweetener and rum as an inebriant, they were both highly significant as another source of cheap carbohydrates. (A British tar in the 18th century got 50% or more of his daily calories from his rum and beer rations.)

I'd love to see someone who had the proper academic background and resources research the impact of those factors on economic and political developments in Europe.

So Europe's development in particular was being fueled by biomass well before the arrival of wdiespread coal use.

Jerry Emanuelson said...

In a 2004 article in the Journal of Experimental Zoology, Reinhard Stindl hypothesized that species only have a finite number of generations before a biological clock in their genomes causes them to go extinct.

Stindl writes, "According to the fossil record, 99.9 percent of all species that have ever lived on Earth have disappeared. However only about 4 percent died out during the five mass extinction events, whereas it seems that the majority of species vanished without any signs of significant earthbound or extraterrestrial physical threats."


If Stindl's hypothesis is correct, then we only have a limited number of generations to take full control of our own genome. The same problem would be faced by any DNA or RNA based organism with linear chromosomes.

For a less technical description of Stindl's hypothesis, see the last page of:

We don't quite have the technical means to confirm Stindl's hypothesis yet, but the appealing thing about it is that it explains so much in many diverse areas, and it helps in explaining the Fermi Paradox. Species may nearly always simply run out of time before they attain the necessary biological and physical technology. Species have a maximum lifespan for the same reason that the individuals of a species have a maximum lifespan.

sociotard said...

I read the Stindl article. My first reaction was "but sharks and crocodiles have remained relatively self-consistant for tens of millions of years." But, that's a Family thing and not a Species thing.

My second was after reading this bit:
"inbreeding, through unknown mechanisms, results in the elongation of telomeres"
1) Gross
2) Haven't they found DNA in the old mummies? those are both hundreds of generations older in humanity's history and were subject to heavy inbreeding. Did they find that the pharohs had long telomeres?

David desJardins said...

I think you deeply misunderstand the potential for stagnation which was the norm in human affairs...

Stagnation just means slower growth. Knowledge still accumulates over time. I certainly don't deny that the progress we've seen could have taken 50% or 100% longer (or, conversely, 50$ shorter). I just don't see how that makes any difference to the original outcome.

If the hypothesis is that human civilizations that have developed writing, tools, etc., could enter a state where they make no technological progress for tens or hundreds of thousands of years, well, that doesn't seem at all possible to me, it's a zero percent chance. And ecological collapse on the scale of Easter Island doesn't really have any effect on the whole planet, any such effects are too localized to make a global difference. It's certainly possible for this to happen in one place or another, but that just means that the eventual breakout of advanced civilization will ultimately happen somewhere else. To posit that it could possibly never happen at all, well, I just don't get it.

Tacitus said...

The Worlds without Fossil Fuels is interesting. You could conjure up a place that is simply....more mountainous. And wet. Hydro power is pretty effective for low tech stuff like milling and manufacturing and eventually for electricity. Let's imagine these mountains also have a fair bit of one of the few metals that occurs in rather pure form, copper, for wires.

Mountains also tend to cut society up into smaller bits, harder to build that whopping aristocratic empire. Switzerland, not Assyria. Might have fewer mega wars.

Agriculture is a little difficult in a "vertical world". But for the diligent...look at China, a substantial population in a place with not that much flat farmland.

Could happen. They might even start flying earlier, lots of peaks to launch gliders...


rewinn said...

" many different Earth species crowd against the glass ceiling of basic vocabulary and tool use..."
Doesn't this points at a local version of Fermi's Paradox: where are the rest of Earth's intelligent species?
It may be that homo sapiens interbred with the some of the tool-using, symbol-making competition. As for the rest, the land-based non-hominids intelligent enough to be trainable have became useful assistants, but carefully bred by us not to be threats. The Galactic parallels are obvious; assuming interbreeding is not an option, how do the Galactics guide our uplift into non-threatening paths? If the key shaping mechanism for a species developing as rapidly as humanity is not slow-moving genetics but more nimbly-changing culture, then what forces can efficiently shape humanity for galactic participation ?
In this context, is it not noteworthy that few, if any, major writers of science fiction have denied being aliens?


If a world roofed in ice has a fortuitously placed moon, perhaps civilization would generate electricity via tides. Water being so much denser than air, tide mills should be much more energy dense than wind mills.

sociotard said...

So, David, what's your bet regarding Egypts Morsi? Do you think he'll walk away from power in a timely manner?

Paul451 said...

"Fortunately they don't have the need for primitive pets,"

Have you seen the number of missing persons? Sure we're not being over-harvested, so they must be breeding domesticated stock, but geez. Hmmm, would be interesting if there were more humans "out there" than down here, in the wide and bizarre varieties typical of pets, while we are the original dull wild-stock with few distinct dull sub-types. And they love their owners, our god-worship trait being the principle reason we were domesticated. (Plus our hands. Because ohmygod look at our widdle hands, we think we're people.)

"In this context, is it not noteworthy that few, if any, major writers of science fiction have denied being aliens?"

And just to think, the bastard actually had the gall to issue a "challenge" to "aliens" on the "internet".

Are 'Cons just a front to allow family and friends from home to visit without adopting ridiculous human disguises? The whole thing sickens me.

Paul451 said...

Re: Narrowing window of knowledge+flexibility in science.

Worse, if we lose that combination of enough knowledge with enough flexibility of mind to further the field, you are likely to see society devolve back into David's favourite 6000 year pyramid, with "science" in place of the old priesthoods. (As the loony left likes to accuse it of being, but actually.) It will drive any young smart creative-types into other fields, so even if they have the genius to both absorb the knowledge quick enough and to expand the field, they just won't be there. Leaving science for the quiet country pastors to run the thousand year old power plants, and the ambitious power hungry bishops to run the academies. So getting to a warp drive won't just take longer, it may be forbidden as heresy.

However, that doesn't solve the radio silence. At least some of those scientific-but-stagnant civilisations will be close enough to hear each other's routine radio emissions with their slightly more advanced than us radio astronomy. That should spark (even if it takes them a few millennia to digest it) a dedicated search for more, if only to control the information. (I can see some responding by banning radio astronomy, but all of them? And natural paranoia says "listen" even if you don't answer.) Eventually, after millions of years, you end up some version of a Sagan Network, which should have been tight-beaming at us the moment they detected unnatural chemicals in our atmosphere indicating industry, which we should have picked up by now.

[The Network would also, IMO, solve the bottleneck for new ideas, simply by having alien minds interpret the same physics through their own mental and cultural filters, adding enough variation to the Network to overcome the lack of young informed minds. Accidental creativity.]

So instead...

Paul451 said...

So instead, a variation of your idea, and of David's Uplift glass ceiling, which I think has been discussed before here. If there are multiple glass ceilings - prokaryotes to eukaryotes, simple eukaryotes to Cambrian complexity, dolphin/chimp level intelligence to human intelligence - then the next one might be the scientific revolution. And we're the only species in the galaxy that spontaneously broke that last barrier, just as our line was the only one on Earth to break the previous barrier.

So we crack the warp drive, head out and discover tens of billions of worlds with prokaryotic life, billions with mushrooms, coral and jellyfish, millions with complex animals occasionally up to chimp-level, and tens of thousands of worlds with intelligent sophonts stuck in the old agrarian empires mode. Tens of thousands of alien species perfectly capable of understanding science, but just failing to have that magic moment where it all came together. Then we get all the fun of golden age pulp SF - space navies, federations/republics/empires, human-like-but-different aliens, white man's burden redux - without worrying why Earth wasn't visited/colonised/broken-up-for-parts before we evolved or why there's no SETI contact now.

Paul451 said...

Ooh, combining all three themes, we aren't the first. But their method of uplift is to abduct and train a handful of young natives, then return them as... the opposite of a saboteur... to seed their civilisation with enough ideas of science to create the philosophical break-throughs necessary to, well, break through the final glass ceiling. And they are doing the same thing all over the galaxy at the same time.

We will emerge to find a galaxy full of young vibrant races also just emerging. With one slightly older race sitting back smugly enjoying the all the noise.

Acacia H. said...

Doubtful. Our geniuses appeared randomly through time up until civilization allowed for a series of civilizations that were all stable at the right time. After all, it doesn't matter if there was an Einstein among the Amerindian tribes right when the small pox and influenza epidemics were busy eradicating these peoples. And a genius could exist in Somalia... and have been gunned down or put to death by militants. (Or even ended up a pirate and used that genius to evade capture.)

Rob H.

Catfish N. Cod said...

@Randy Winn: "Doesn't this points at a local version of Fermi's Paradox: where are the rest of Earth's intelligent species?"

Do I have to point out the dolphins? Yes, we eliminated or interbred with the ones *in our eco-niche*. But that leaves plenty of space elsewhere. I'm not convinced the dolphins are actually pre-sapient.

No, the real question is why no other species evolved intelligence prior to us. There has been a sufficient level of complexity in multicellular creatures and their brains since the Permian at least. Either there *were* (and they caused the mass extinctions, erasing the evidence in the process) or there were not and we have to wonder why. If we really have as many pre-sapient species as Dr. Brin hypothesizes, we have to ask what f(i) really is -- the number of presapient species N(ps) is a subfactor of f(i), and if it's high, the remaining full sapience fraction f(fs) is that much lower.

I'm still interested in exploring the subfactors of f(c). Dr. Brin has explored one mode -- a potential tendency to develop pyramidal resource allocation that impedes progress. But what if the species faces much greater challenges in acquiring resources, living space, etc. than we do? What if -- due to any number of biological or cultural specializations -- they're not INTERESTED in expanding their territory? Could there be a scenario like the venerable game series CIVILIZATION, where many planetary versions of those little villages that you find in exploration exist for every species that actually even TRIES to surmount the hurdles to spacefaring?

There are many factors that predispose us to developing an exploratory civilization -- territoriality, curiosity, cooperative social interactions, evolutionary adaptations to long-distance travel, and a series of biomes requiring minimal behavioral adaptation. (What if the Ice Age never ended? What if the sea were poisonous to us? What if we had a nutritional requirement we could only obtain in one place? What if traveling too far from home was disorienting?) I am unconvinced by arguments that our particular set of adaptations will inevitably be repeated in all intelligent species -- which is another way of saying that the only way to evolve intelligence is the way we did it.

What if intelligence is common, but travel and communication are rare?

Alfred Differ said...

Stagnation does not mean slower growth. There are examples in our history of populations that got cut off from their neighbors in the sense of trade. Look up what happened in Tasmania after the ice melted. The short version is they got cut off and lost skills over the ensuing generations because they had to become more self-sufficient, thus they had less time to bother with teaching peripheral skills. Their tech and population shrank in unison.

I've seen many argue that our innovations caused our population to boom, but I think they have it backwards. I argue that our innovation and population explosions aren't just correlated, but necessarily linked. Historically speaking, the percentage of us involved in innovation attempts is fairly small, so an innovation explosion requires a population explosion. This isn’t a chicken and egg problem though. People have to come first. In hind sight, fossil fuel innovation was easy compared to renewable energy techniques. That ease appears as population in the next generation because of a feedback loop, but I argue that people who think innovation caused population miss one step of the feedback cycle.

If we had been forced to stick to renewables our population would be much smaller at this point, thus the number of innovators in past and present generations would be smaller. I have no doubt that we would be nowhere near the tech level we have now and I worry there is a reasonable chance that we would be growing too slow to make up for the damage we do to our own croplands. I know people who argue that we naturally destroy our environment as if we were a cancer, but I’m not one of them. What I do recognize is that we have innovated very rapidly in the last two centuries and learned how we were doing the damage. Without that burst of knowledge pushing us through one of David’s glass ceilings (a thing we tend to recognize after we have broken through) we might have slid back down the hill we were climbing just before the industrial revolution. While wood and water power were present at the start of our boom, I seriously doubt they would have been enough to get through the ceiling we shattered with the steam engine.

Innovation requires a population that can set aside the time of some of its people to search potentially fruitless ideas. Whether our population is constrained by energy limits or contraception techniques, I argue that they also limit the rate of innovation. It is easy to argue that the steam engine ended the institution of slavery, but I think the best explanation for the European explosion that began in the 17th century is a new tool that came in the shape of a social institution. The idea market we call Science enabled innovators to more quickly sift through what might be true and remove what was demonstrably false. This institution was like the invention of a new and better stone axe in that those who had it had an innovation advantage. That advantage is apparent enough that the percentage of us devoted to innovation increases with each generation and THAT feedback loop shattered the glass.

Acacia H. said...

There is something else to consider: the effect that the aristocracy and oligarchy has on technological advancement. An example of this can be found with Bell Laboratories/Ma Bell. This monopoly company was paying for research into various technologies over a century ago. One of the discoveries... was I believe for some form of electronic memory system usable in computers and computing. They buried the research. They felt it not only had no application for the telephone industry, but that it could actually THREATEN their current monopoly.

In short, we could have had electronic computers... during or even before World War II. But a monopolistic entity squelched the advancement. Similarly, a government could refuse to allow an advancement - say Germany had banned the Printing Press and destroyed all plans for it and killed its creator as an abomination against God (because they were printing Bibles)?

Thus the society in which a genius is raised can also impact on technological innovations... because a society that views innovations as a threat will do everything in its power to keep innovations from arising or from escaping to another nation.

Rob H.

David desJardins said...

Historically speaking, the percentage of us involved in innovation attempts is fairly small, so an innovation explosion requires a population explosion.

This is clearly wrong. By far the biggest factor in "innovation attempts", at least among human beings, is loading the dice to favor innovation, not throwing more dice. You can increase the number of innovators in a society by a factor of 10 or 100 or 1000 just through social changes. Whereas the number of people hardly matters at all. There are billions of poor people in the world who are never going to discover new methods of controlled fusion. You could increase the number of such people by 100 and it wouldn't matter at all.

Alfred Differ said...


There is the history of the aristocrats acting as patrons to counter the impact of those who would squelch innovation. David's description in the latest book portrays the conflict well. There are potential traitors within the aristocratic clade and we benefit from their actions. There are also the unseen effects their non-traitors don't foresee. We benefit from those too.


Loading the dice certainly would help. I apologize if I sound dismissive of that possibility, but I'm not convinced that we know how to load them. I'm even less convinced that we knew how to do it in the past. The closest thing I can think of is a subsidized/free education system. Redistributing some of our wealth in order to educate more people would load the dice a bit, but my experience with our education institution suggests it is better at replicating what is already known than it is at innovating. Innovation, when it occurs at learning institution, is often associated with failed replication attempts. I know this from my own personal experience trying to learn physics in grad school. At some point with some concepts, I couldn’t understand the professors and books and had to invent my own ways. I knew the problems were solvable, thus I had a leg up in the effort, but part of what I know I had to invent even in the presence of those who were willing to teach me their ways. I suspect this happens a lot and eventually happens to all of us if we work hard enough to become expert.

Poor people don’t have to innovate fusion in one leap any more than our paleolithic ancestors had to innovate moon rockets. As long as they CAN innovate, they will solve little problems they face every day and occasionally trip across big ideas. The more of us stumbling about, the higher the chances are of big ideas being found.

I’d argue that the contributions of the Puritans (poor by our standards) came at a time of a weak government and support for their research efforts by a faith meme. They didn’t invent fusion either. Instead, they created a social institution that took Science out of the hands of a few smart people living on patronage (and a few smart, rich people too) and made of it a market with a large number of traders. They increased the number of us throwing dice.

ERic said...

Apologies if this has already been mentioned, but I did a little searching on the page and didn't see it:

A Drake Equation Calculator on the BBC website

Ian Gould said...

There are examples in our history of populations that got cut off from their neighbors in the sense of trade. Look up what happened in Tasmania after the ice melted. The short version is they got cut off and lost skills over the ensuing generations because they had to become more self-sufficient, thus they had less time to bother with teaching peripheral skills. Their tech and population shrank in unison.- adiffer

The latest archaeological evidence is that the Tasmanians had started expanding their technology (i.e. making boats) in the last millenium prior to European colonization and that their population was growing.

The "dying race" hypothesis was essentially concocted by guilty Australians to excuse genocide.

Ian Gould said...

Paul - but what if The Network requires a consensus amongst all members before adding new members and the debate and voting has to proceed at sublight speed?

David Brin said...

Jiminy! You guys got off to a slow start this time, but I am delaying my next blog because you fellows are having a terrific day!

This blogmunity is one of the hidden gems of the web and I am proud of you.


Wow, Ian, excellent missive about the bio-riches that came from early N. America. As distinct from the gold sought by the Spaniards and also from the genetic crops that were brought from America, a separate matter.

Jerry E. The Stindl hypothesis is weak in many ways. Some species of Shark have been around for eons. Homo Erectus for vastly longer stretches than homo sapiens has been around. Above all, "new" species generally continue a previous one.

DdJ: Yes you don't get it. Please go read COLLAPSE. Smart but crude humanity relentlessly degraded its own environments long before gaining technology. Irrigation made salt deserts of the middle east, protecting goat herds helped spread the Sahara and many other deserts. California's central valley today is in a serious salinification crisis from irrigation. You keep repeating that SLOW does not prevent INEVITABLE scientific advancement. This is an article and declaration of faith, not a hypothesis that stands up to scrutiny.

When Europeans - amid a renaissance boom fostered by special circumstances - came to Ming China they were impressed. But in most ways Ming China had forgotten most of its science and was sinking into stagnation and forgetfulness. The great Muslim centers from Timbuctu and Salamanca to Baghdad had similarly withered. You presume teleology where there is none.

adiffer summarizes this point brilliantly.

Rewinn: cool thought re roofed worlds and tides.

Sociotard, I have no idea re Morsi. It is a tipping point. It Egyptian society advanced enough to prevent an Iranian disaster?

Robert describes the scenario also shown in the Ray Bradbury story about the Chinese Emperor who rewards the inventor of a flying machine with a day of pleasure, then kills him and burns the device. Anyone know that story's name?

Paul, I was gonna give Ian post-of-the-day but you and Randy are really on, as well! In fact, your cascade of glass ceilings is exactly what I consider to be the top-credible Fermi... augmented by the fact that the Earth may have been unusually calm, nice in orbit, protected and so on. And I'll not refuse the importance of the moon, just only at a 10% level, not a decider. All of this may FEED into the cascade of glass ceilings.

As for returning humans to Earth as guides, well, Yes. They would be sci fi authors, wouldn't they? Leaving clues laced through their works... wait! Where did I already see that?

Catfish, good points. But dig it. Any species that CAN do starships and decides not to... but has a small subset that goes ahead anyway... that subset will inherit the stars. Well... if they succeed.

"What if intelligence is common, but travel and communication are rare?" Indeed, Intelligent herbivores may be paranoid and incurious. Intelligent carnivores may be too obsessed with inward competition. Sapient omnivores who are solitary (bears) may lack the ability to cooperate. and so on.

DdJ I agree that social matters are important. A non-pyramidal, enlightenment society rewards innovation... and we finally got such a society from the rough phases helped by new powers and new fuels. But do not discount numbers! If the world's new middle class educates all its kids, especially girls...

...AND if hollywood succeeds at spreading the best western memes ... then those vast numbers will bring much innovation.

Again, wow, glad y'all are having fun! Braaaaaaaaaaaaiins!

David desJardins said...

You definitely don't need teleology to think that progress is inevitable. You just need "learning" to be asymmetrical with "forgetting". I think Diamond's work is fine, but it doesn't say anything at all about global progress, only about local progress. By definition, local civilizations can only produce local collapse. These are at most incidental to the overall course of progress, at worst your civilization reverts and then you try again. Or your civilization reverts but meanwhile some civilization elsewhere is moving forward. You can't have a global collapse until you have a global civilization, which is the point we're now at but is past the bar we were discussing. I don't think it's inevitable for humans to colonize space. But it's inevitable, once humans come into existence (and, of course, barring some global catastrophe like asteroid impact) for them to advance to a modern technological level and form a global civilization. It could happen faster or slower, but it has to happen eventually. And things like access to fossil fuels are irrelevant to that.

I'm really surprised to discover that people could question this.

Ian Gould said...

A question of relevance to SETI which I've raised before but didn't really get much of a response.

Assume today we detected a extraterrestrial radio signal, how long would it take us to respond?

First the scientists would likely spend a year or so double-checking their data.

Then they'd either submit it for peer review or notify the IAU.

who've they talked to would likely spend another year or so double-checking their work and looking for independent confirmation.

Then they go public and - what?

Presumably, the world's governments get together to discuss how and whether to respond.

Any government acting unilaterally would probably come under huge pressure not to respond. Does aayone really want North Korea downloading blueprints for a phaser?

So how long does it take for the government's to come to a decision?

If they decide to respond, how long does it take for them to negotiate for free and equal access to the means of communication and any data received.

How long does it take to actually design and build, say, a multi-megawatt orbital laser? (And how does North korea respond to having an orbital laser going over their heads daily?)

And to agree on the content of the message?

Who builds it? Roskosmos? NASA? Elon Musk?

so how long are we talking from first detection to a response?

Six months?

A year?

5 years?



Would a hypothetical alien civilization take more or less time?

Maybe the Tau Cetan beacon lost its funding half way through construction due to budget cuts; the Eridanean one was lost in a launch accident and the Centauran one is built but environmentalists and social justice activists are blocking it in the courts because its clearly an attempt to exploit the poor simple Earth folk? (Or alternately the local Republicans think its all a hoax because it clearly contradicts the word of Ghod.)

David desJardins said...

I guess it depends what kind of a signal. An obviously artificial but otherwise uninterpretable signal from a galaxy a million lightyears away would be pretty different from a message written in English from a ship orbiting Jupiter.

BCRion said...

A thought for your consideration on the Fermi paradox.

The discovery of fission led to the first way we could destroy our civilization through war. I wonder if we happened to get lucky about the societal conditions that existed when nuclear weapons were first developed.

Perhaps fission was discovered late here on Earth relative to social advancements that occurred. Suppose development of democratic systems of government are very rare throughout the universe. The more typical path may be that feudal systems persist through much slower technological development. Eventually, fission is discovered and atomic weaponry is invented for use by the elites in a largely illiterate society. They use it against enemies, seeing the power offered, others come to technological parity soon enough though hook or crook. Eventually, nuclear exchanges escalate to the point of damaging the environment to the point where civilization collapses.

Instead, here on Earth, it was a liberal democracy that developed it first, mainly out of the fear that the Nazis would acquire it first -- the Germans discovered fission after all, another coincidence that motivated the U.S. Had fission been discovered in peacetime, perhaps it would have been the Soviet Union that would have been first. I doubt Stalin would have hesitated using it aggressively had the U.S. not served as a counterbalance.

Or consider if it had been developed prior to mass media and radio, such that the devastation nuclear war causes would not be widely known except by the elites. Perhaps the U.S. using it during a time when mass media was available, made people acutely aware of the possible devastation. Having leaders accountable to voters, it perhaps became impossible for the U.S. to muster the political will to use the brief advantage for aggression.

In other words, in this hypothesis, numerous unique circumstances happened in the right order that created a rare situation where nuclear weaponry would not be used in anger and spiral out of control, therefore allowing us to avoid one of many pitfalls.

Ian Gould said...

Just a note on technology and egalitarian societies.

The key proximate events leading to liberal democracy were the English Revolution of 1688; the American Revolution of 1776 and the French Revolution of 1789.

Arguably the most important of these was the English Revolution - not so much because it brought William and Mary to the thronw but because Parliament effectively asserted its sovereignty for the first time by deposing James the Second and declaring itself "the crown" until such time as a new monarch was chosen.

These all preceded the widespread use of fossil fuels.

David Brin said...

David you deny teleology, yet you keep insisting on "inevitability". Please grok. 99% of human cultures entered a style of governance that ensured conservatism toward science and research, top-down avoidance of criticism and hence lousy statecraft, and nasty intellectual property regimes that encourage secrecy... hence we lost the Baghdad Battery and Anthikithera Device and steam engines and Damascus Steel and Greek Fire and so many other advances that would have powered industries, otherwise.

Now add in the monkey factor... we may be less regimented than most races. Sorry. Add it horrible eco self-destruction here, then there, then over there and you have a recipe for impoverishment.

I am not saying this is THE 'fermi" explanation. But to dismiss it so blithely seems foolish.

Ian I served on the SETI Protocols committee. As soon as it is confirmed to be extrasolar in origin ALL data will be mass published world wide. We'll try to hold rushed discussions. But everybody on Earth will be building radio dishes and within a years screaming their heads off.

Alfred Differ said...


Thank you.

I'll track down the pesky 'dying race' meme to see if my source is infected. If so, I'll dose up on the appropriate antibiotic. 8)

I have little doubt the revolution of 1688 is the more important one. They set a precedent some of their colonies chose to follow later. On a personal level, though, I don't see the French revolution as being the same kind of event. They were all revolutions for sure, but the French pursued a different philosophical path from those of us in the English speaking world. Liberty isn't the same as Equality.

David desJardins said...

Perhaps I don't understand what you mean by "teleology". I thought that teleology was the idea that a particular outcome is predetermined. I'm not arguing for any predetermined outcome, just that, eventually, sufficient technology to support a global civilization must develop, one way or another. It's like the difference between dropping a bowl of marbles on the floor, and claiming that the specific final arrangement was inevitable (silly) or claiming that the entropy had to increase (inevitable due to the laws of thermodynamics). Obviously there are still lots and lots of different high-entropy outcomes available, so this is not teleological, in my view.

To get my result, you only have to accept some basic propositions: (1) humans will keep trying to improve their technology, (2) completely losing discoveries is somewhat harder than making them, and (3) until human civilization has global reach, it can't destroy itself globally. None of these seem very controversial.

So I think human technological advancement to a global civilization was inevitable, the only question was about timing. Your examples illustrate that, there were plenty of missed opportunities for faster advancement, yet the ultimate result was still reached.

Now, you also make a different point that an alien species could have the intellectual abilities of humans, but not the curiosity or drive or some other attribute that causes us to seek progress. I agree this is entirely valid. It seems unlikely to me that a large number of intelligent species would evolve across the universe, but virtually none of them would be much interested in using their intelligence to develop technology and improve their lives. But while it seems unlikely, it's not logically inconsistent.

Alex Tolley said...

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

Apart from the octopus, all the other examples are from the phylum Chordata. Thus the path to intelligence is not just life to prokaryotes to eukaryote animals, but a particular body plan that happened to prove very successful with forms that were selected for individual intelligence. This may be an unlikely fluke. Even if chordates never existed, is there any evidence that molluscs could have fulfilled the same terrestrial role that would lead to industrial civilization?

On other worlds, we have to consider whether alternative body plans might ever lead to intelligence. Perhaps we are truly unique in that regard.

I tend to think, even though currently unproven, that many worlds will harbor life, even complex life. But perhaps not life intelligent enough to create a space faring technology, but merely crude tool using. IOW, I am optimistic that the "great filter" is behind us, not in front of us.

David Brin said...

Many, many regions on Earth entered into long, slow curves of grinding ecological decline because human cultures were advanced enough to chop the forests spread salt thru irrigation, protect herds that ravaged the land... but not advanced enough to know what they were doing. While clinging to social structures that actively delayed that day.

Sure, that day might eventually come. But if it's grindingly slow, what kind of Earth would be left to pay the cost of interstellar culture? And if it's even slower elsewhere?

matthew said...

What if fossil fuels are common on planets with intelligent life? Say, much more common than they are here? Then we might have a situation where the Fermi filter that we are currently facing -massive climate change that threatens the life carrying capacity of our planet- what if that filter usually comes earlier in a social maturity order? Think of the roman empire burning gigatons of crude oil. Planetary ecological collapse before the technology of science to understand the cause of the collapse, let alone remediation of the underlying problems

rewinn said...

David desJardins said...

"...You can't have a global collapse until you have a global civilization..."

I disagree. Once humanity figured out that coal and petroleum burn nicely, it's just a matter of time before global warming kicks in; no need for a global civilization, merely for independent discovery or casual sharing of information.

IIRC the idea that greenhouse gasses could threaten our planet is not at all obvious even to scientists; thousands of academics could have done the math a century ago but it was only when Hansen tried to figure out Venus that the danger to Earth became apparent.

We may have much for which to thank the Morning Star!

Catfish N. Cod said...

"...Do I have to point out the dolphins?..."

I explicitly referred to "land-based" because I have no idea why ocean-borne intelligences haven't evolved to match us. Although, as you may be suggesting, it could be that dolphins have done so.

Perhaps the 'phins are so well adapted to their environment that they feel no need to develop technology. An historical parallel is my own Puget Sound country, where Indians have lived since before the Celts invaded England; their technology never got beyond the whale-hunting canoe, perhaps because it is such an easy place to live. Every day, the tide pulls back to reveal another meal, so what's the big deal with agriculture?

Might dolphins (and Galactics in general) be caught in a similar Cornucopia Trap?

Catfish N. Cod said...

@Dr. Brin: Catfish, good points. But dig it. Any species that CAN do starships and decides not to... but has a small subset that goes ahead anyway... that subset will inherit the stars. Well... if they succeed.

I wasn't referring to species with the capabilities and a cultural reason not to. I meant species that are genetically or environmentally predisposed not to. In the manner of the "cascade of glass ceilings" we are talking about, I'm just pointing out that there's little reason the anaerobe/aerobe ceiling must be the one that most worlds block at. Or the pre-sapient/sapient ceiling. Or the development of a culture (that is to say, a means of intraspecies interaction) that permits rapid technological development. You also have to ask if, like 90% of all macroscopic species on Earth, most intelligent species are trapped by their biology and environment... we were for 90-99% of our lifetime as a species! Homo erectus never made it beyond the equatorial belt. Homo sapiens made a few forays out of Africa before the Toba event nearly wiped us. Then we, too, spread around the equator... but not until the melting did we expand our range to all of Earth's habitable landmasses.

Could we have made it if we hadn't had a vast number of habitats to try? If you can only develop a technological culture in a single environment suited to your biology, you may not learn how to colonize outside it before Jared Diamond's collapse nails you...

Acacia H. said...

Here's something to consider: Scientists drilled to a brine lake and found microorganisms in the extremely salty environment. Microorganisms. Not fish. Not amphibians. Not reptiles. Microorganisms. Life exists in that extremely hostile environment... and was isolated for a long long time, but never outgrew the single-cell organism stage.

If there is life on Europa or on any number of ice worlds out there, it will likely be as microorganisms. Not multicellular life... or if it is multicellular, very likely not intelligent, let alone sapient.

And this is the thing to consider: if we find microorganisms on Mars... does it matter? I know there is an "ethical" group that claims Mars should remain untouched if it bears life (and some who feel it should remain untouched anyway, along with the Moon, the Asteroids, and pretty much most of the Earth to boot), but if it's unintelligent and non-multicellular life, why does it matter? It's not like we'd be going to Mars and killing off Martian Indians to steal their gold and oil.

Rob H.

Acacia H. said...

Oh dear. It seems the Orion Space Capsule cracked under pressure - literally. Let's see... the Bush Space Capsule that was forced down the Obama Administration's throat has proven flawed and cracked under a simple pressure test. And yet Republicans (and Democrats) insist that this is the path we need to take to the stars (or solar system at least) rather than trusting private space industry?

It'll be interesting to see if the human-rated Dragon capsule is able to handle those pressure tests. And given the technological upgrades of the Dragon to the older systems (like having rockets in the sides of the capsule for use in landing or escape rather than a rocket tower that is ejected partway into flight to become Yet Another Piece Of Debris), the question isn't "is the future of space travel through private industry" but rather "why are we wasting taxpayer dollars on a flawed and failed system when private industry is proving better apt at the job?"

Rob H.

P.S. - Dr. Brin, you didn't answer my questions on the underlined sections of "Existence" or if there is any sort of "term dictionary/vocabulary" for people to get a better understanding of your futurese

Tacitus said...

I'm actually kinda happy they only found unicellulars down there in that brine lake. Imagine what it would have been like to sink a pipe down there and have "somebody" start banging on it in the cliched fashion of telling the upstairs neighbors to stop making so much racket!

Acacia H. said...

Oh, I'm not disappointed either, Tacitus. We didn't need an X-Files episode or "The Thing From Another Planet" being played out in reality. My point was just that it's unlikely we'll see advanced organisms in the seas of Europa or on any ice world. I'm doubtful we'll even find any multicellular life on Titan, and that world's got an atmosphere rather than ice-covered oceans.

Rob H.

Paul451 said...

Rob H.,
Re: Alien uplifters & historical geniuses

But that kind of proves my point. It's not that we never had geniuses before the renaissance and the following scientific and democratic revolutions, it's that their genius was limited by adaptation to their environment. Just as there are plenty of highly intelligent animals adapted perhaps a fraction to tightly their niches, which limits their ability to go further. Therefore there's nothing special in the uplifting aliens reaching us during the European middle ages. Could have happened during the ancient Greek or Roman era, the post-Greek Arab and Indian scholars, the Egyptian or Chinese or Mayan empires (of perhaps better, the smaller nations around them to avoid the monopoly protection effect you mentioned.) How many technologies were invented prior to the modern period that stalled? Steel, printing, steam. How many civilisations seemed to be right on the edge? (Looking back, the Greeks got so close. They are the dolphins of civilisation.)

"it doesn't matter if there was an Einstein among the Amerindian tribes right when the small pox and influenza epidemics"

Not an Einstein, but how about a Jenner to re-discover variolation? And a Pasteur to work out where the sickness came from, and a Caesar to bring the tribes together long enough to end the threat of invasion while their nations heal and repopulate. And that repopulation leading to a surge of ideas and innovation that results in some kind of, oh I don't know... scientific renaissance.

Re: SF writers.
Isn't it an interesting coincidence that when we seemed to be getting stuck with the concept of "alien" meaning "enemy", from War of the Worlds to golden era pulp SF, suddenly a handful of SF writers (and later people like Gene Roddenberry) emerged to promote the idea of aliens as potential allies, friends, and yes, even lovers Captain. And when the Nazi's, and the Victorians before them, left the concept of eugenics as a universal blasphemy, suddenly a scientist in California gets the idea to write stories about uplifting dolphins.

Paul451 said...

Re: Sagan Networks as a buffer against post-scientific stagnation.
"but what if The Network requires a consensus amongst all members before adding new members and the debate and voting has to proceed at sublight speed?"

Then it would have already been overtaken by a less restrictive Network. Besides, like the Uplift culture in David's universe, I think that a contact culture would become the norm. After all, if you are the millionth link in a chain spanning an entire galaxy, and you know they are all watching your reaction, there is a hell of a lot of psychological pressure supporting the pro-contact faction in your society. For you not to respond and "break the chain", your whole culture would have to be uniformly against the idea. (Or else ruled by a hierarchy that enforces such uniformity.) And even then, others would see you as damage to the Network and route around you.

check peer-review recheck... "Then they go public"

Yeah, that story isn't going to leak. From scientists.

Paul451 said...

"fission led to the first way we could destroy our civilization through war."

Not really. It would have set us back. But it's hard to produce an extinction level event with regular old nukes. Or set back a technological civilisation far enough, for long enough, for them to be unable to rebuild. IMO, civilisations only fail when there is a constant downward pressure on them. (An eco-collapse, a resource loss, a slow multi-generational stagnation.) A sudden sharp shock leaves a culture of survivors that fundamentally believe in the normality of their prior civilisation, one they desperately want back. A slow stagnation produces a culture that accepts the normality of decline.

I made this point with the comparison of the film version of The Postman and the book. David had to create the accursed Holnists to explain why civilisation hadn't grown back. The survivors would have assumed recovery. Everyone with rank, a uniform or a badge would automatically be seen as a local authority. Some would abuse it, but most would assume they were responsible for rebuilding and try to connect with their fellow authorities in surrounding areas. The film, like most post-Apocalypse fiction, ignores the need for something to cause a loss of will. [David also added other disasters to explain why other continents failed to recover, such as the Asian pandemics. Although, IMO, it still isn't enough, too many potential hubs of recovery, not enough nukes. Too many people with ham radios, too many people know know how to build ham radios.]

[Also, have we truly crossed this bridge? There's still plenty of scenarios that allow us to take Johnny Atom to war.]

"I doubt Stalin would have hesitated using it aggressively had the U.S. not served as a counterbalance."

Errr, it's not as if the US hesitated to it use it aggressively before the Soviets created as a counterbalance.

David Brin said...

Catfish, I grasp your gist. Indeed, one of my top five "fermis" is that other sapients achieve full capability too slowly or are otherwise crippled from achieving their potential.

I do think folks bend over backwards to make excuses that dolphins must be as smart as us "in their own way." No one ever offers a scintilla of evidence. Language? other communication? Problem solving? Even problem solving that's intrinsically underwater... they are clever and they clearly WANT to be smart. But they are frustrated not to be able to think through things a human 8 year old can. I am not saying they lack honor and dignity and merit respect! My books indicate respect. But they aren't "intelligent."

Robert, I have no glossary of neologisms for EXISTENCE. Alas. Ask about a few here and I might answer... or else just respond with an evil cackle....

Paul451 the best example of how stalwart people would actually be after a nuclear war was the lovely-chilling post-nuke film TESTAMENT. Very feminine and the opposite of Mad Max. The cops stay on duty till they drop. some looting but basically Folks try to help each other and keep it together. Weep-worthy.

Acacia H. said...

You do know this claim that "aliens did it" is no different than the religious claiming God created mankind and the universe in seven days, don't you? Seriously. Is it so difficult to accept the concept that humanity pulled itself up by its own bootstraps, that there are no ancient astronauts that guided us through the years, and that maybe, just maybe, humanity as a whole is able to do good things without an external force making us?

Why did science fiction writers start writing about "good" aliens? Easy! Because they are contrarians! Because they decided to go "but what if..." and write the alternative perspective! Is this site not called Contrary Brin? Why? Because Dr. Brin... is a contrarian! Because he doesn't just go with the common perceived belief and says "yeah, but what if?"

We don't need ancient astronauts. We don't need aliens. Humanity itself is a grand and glorious thing... and it is that because humanity makes itself great. Yes, we're not perfect. But you know something? We don't need Gods or Aliens to allow us to excel. We just need to believe in ourselves.

Rob H.

David desJardins said...

Once humanity figured out that coal and petroleum burn nicely, it's just a matter of time before global warming kicks in; no need for a global civilization, merely for independent discovery or casual sharing of information.

A pre-industrial society just can't burn very much coal, much less extract oil and gas from deep underground and use it in a productive way. You can't realistically get significant warming this way, not on our planet. And what if you did? Global warming itself isn't an existential threat to human life. Extinction of species, property damage, and the like, are big concerns for us, but they aren't going to eliminate human life. Humans survived Ice Ages with 200 feet of ice over where I'm sitting right now.

Paul451 said...

Errr, Rob, you do realise I don't in any way seriously believe that aliens created the renaissance or the scientific revolution? (Or science fiction for that matter.)

rewinn said...

David desJardins said...
"... Global warming itself isn't an existential threat to human life...."

In a paragraph full of wrong statements, that is the most mind-bogglingly wrongest.

The rest of the paragraph is simply a failure of math and of imagination, but to suggest that humanity could survive turning Earth into Venus without inventing some magic level of technology requires further explanation.

Alfred Differ said...

I have to agree that use of fossil fuels with pre-industrial tech wouldn't be much of a threat. Not only can we not burn the stuff fast enough to notice, we can't get at the stuff fast enough to matter. If I remember my history correctly, the steam engine was developed first as a pump for a mine to get water out. Without the feedback loop that connects tech innovations to access to fossil fuels, the costs associated with coal and oil would still be very high. That alone would prevent their widespread usage.

On top of that, oil desn't burn all that nicely. Wood is far superior due to its form factor. If I want to do a backyard BBQ with chicken, the easiest way (for a very long time) involved wood. Look at the tech related to the gas bottles in use today and you'll see a complicated and costly set of innovations that would not have been done if an even more complicated and costly infrastructure were not already in place. Remove all that and our BBQ's would be firepits.

A couple of nits now... 8)

1. Hansen wasn't the first. Look through the history regarding the discovery of CO2 and shortly after they noticed its IR absorption spectrum, someone speculated that industrial production could alter the climate. The history is easy to look up and fun to read and use given the current skepticism of some of our politicians. 8)

2. There is plenty of evidence that modern humans expanded away from the equator before the ice melted. You don't get Native American people here in time to match the evidence otherwise. Of course, there is also evidence that those who went far north also got isolated and killed/culled.

Acacia H. said...

While it would be possible with today's technology to turn Earth into Venus, the level of technology a 100 years ago would have been very hard pressed to do that. What would happen is uncontrolled climate change that would devastate civilization and eliminate many species (and probably cause a number of human societies to fall)... but there is still a chance humanity would survive. And after a few thousand years the environment would stabilize. We probably won't be a technological species at that point... but humanity is if anything else... adaptable.

Rob H.

Alfred Differ said...

I don't think DdJ is suggesting we could survive turning Earth into Venus. He might be questioning whether we COULD turn it into Venus, though. I would join him in that doubt.

I don't view climate change as an existential threat either. I see it as a moral threat. If I sit on my behind and do nothing, I'm morally culpable for the mega(giga)deaths that might occur.

I think it is a stretch, though, to argue that humans will go extinct. The conditions that would lead to a runaway greenhouse that involve our input would all fail when our actions changed under climate pressures.

David desJardins said...

The rest of the paragraph is simply a failure of math and of imagination, but to suggest that humanity could survive turning Earth into Venus without inventing some magic level of technology requires further explanation.

Come on, Randy. You're going completely off the deep end. Venus's atmosphere weighs 4.8e20 kg, and 96.5% of that is CO2, so that's 4.6e20 kg of CO2. Human emissions today (this is at the peak consumption rate of a highly industrial society that extracts fossil fuels anywhere and anywhere we can find them) amount to 3e13 kg of CO2 per year. So at the current rate, it would take 15 million years to emit enough CO2 to turn Earth's atmosphere into Venus's. That's with all of our industrial society behind us, if you did it with a preindustrial society burning whatever coal they could easily find, it would maybe take 300 million years. That's if that much fossil fuel existed, which it doesn't, not remotely.

Earth isn't turning into Venus. Regardless of whether humans extract and burn every molecule of coal and hydrocarbons that we can find.

Paul451 said...

The "runaway greenhouse" scenario is that our emissions warm the oceans enough to cause the release of the methane clathrates, which causes enough warming to cause the oceans to release most of the dissolved CO2/etc (hot water dissolves less gas), etc etc, which causes enough warming to dissociate limestone, which feeds on itself until we're left with Venus II.

Why it's crap is that we've had up to ten degrees warming in the past (possibly from a significant clathrate release, caused one of the five major extinctions, bad thing, very bad thing) without an unstoppable runaway feedback.

duncan cairncross said...

Hi Paul,
"Why it's crap is that we've had up to ten degrees warming in the past (possibly from a significant clathrate release, caused one of the five major extinctions, bad thing, very bad thing) without an unstoppable runaway feedback."

But since then the sun has got brighter - if a similar event occurred now... - we don't know

It's probably very long odds BUT a very bad prize

As the sun ages it's output increases, the "Goldilocks zone" moves outwards,

We believe that the earth is near the inner edge of that zone - certainly closer to the inner edge than it was hundreds of millions of years ago

Acacia H. said...

The thing to remember is this: methane breaks down in the atmosphere. While it has a significantly higher heat retention ability, if significant methane clathrates levels are released, then when they run their course over a hundred years they'll break down into carbon dioxide, which has a lower heat retention ability. At this point, the plants that survived (and some would) would start pulling that carbon out of the atmosphere in greater and greater numbers.

Assuming some form of humanity survives and that it retains some technology (very likely), then this would be encouraged by man and you'd see the terraforming of the Earth into a cooler environment. Seeing this entire worse case scenario would happen in probably a thousand years, it's likely the ultra-rich would be able to set up enclaves and try to wait out the massive climate change. Then they'd reemerge on a massively changed world as the lords and masters of all they see. And then go to war with other enclaves. ;)

Rob H.

Ian Gould said...

There's a couple of sf works that are relevant to the discussion here but I've forgotten both the names and the authors.

In one - a series of short stories and novellas published in one of the digests - it turns out that anti-gravity and FTL drive are ludicrously easy.

Most species discover the technology while still in the bronze age - at which point outward expansion takes over as the main form of development and most other technologies stagnate.

So when the first alien ship lands on Earth, they attempt to overawe the natives with the might of their match-lock muskets.

The other was a novel set in a galaxy divided between alpha Humans and Beta Humans. The Alphas are our descendants - the Betas are the descendants of humans taken as servants by aliens centuries ago.

(Actually if you were considering first contact, setting up a small offworld colony using abductees, letting it develop undisturbed for a couple of hundred years then contacting them might be the way to go.

Alfred Differ said...

It would take much more than all the carbon in the fossil fuels to get a heavy Venus-like atmosphere. I think you have to burn the limestone currently locked up in the Earth's crust. That's where most of it went when the water precipated out of the atmosphere.

If I remember right, most of our second generation atmosphere is sitting on the ground or just under ground.

David Brin said...


Only now it's time to move on to the next posting.


rewinn said...

Since I was discourteous enough not to explain that "Venus" was a bit of hyperbole, let me note that an extinction event does not require heating our atmosphere to that of Venus'; merely boiling our oceans would be plenty, but a good deal less would suffice to end its role in the renewal of oxygen. Nor is an atmospheric composition as that of Venus required to perform such feats.

As for the math, I will let Dr. Hansen explain, since he's the actual scientist and expert on the subject.

A world without a global civilization is quite capable of releasing sufficient stored carbon (and other greenhouse effectors) into the atmosphere, so long as it has enough non-global civilizations working on the problem; it just takes longer than we are observing in our reality. Historical speculation, such as what might happen in the absence of a global civilization, cannot argue that a thing cannot happen because it did not happen (post non hoc ergo propter non hoc ;-)). It is a fortunate historical accident that models such as Stable Medieval China did not sufficiently dominate the other land masses to develop our world as Eternally Feudal Earth, with no-one especially interested in studying the problem of increasing global temperature and (more importantly) capable of urging the other civilizations to cooperate in solving it (in a pre-nuclear world, forgoing the burning of carbon would have adverse military consequences.)

But this is all speculation and if it's time to move onward, well enough.

David desJardins said...

Unfortunately, Hansen doesn't say that CO2 emissions at a much slower rate than modern industrial society (or even at our current rate, or even at a significantly higher rate) can do anything remotely like boiling the oceans, or turning our planet into Venus. You should follow your own link, because Hansen's site doesn't say anything like what you say it does. It says we'll have more storms, mass extinctions, coastal flooding, etc. Huge costs, but not remotely like an extinction of human civilization.

Unknown said...

The Fermi paradox may be more mundane than it looks. One of the problems with SETI is finding a needle in a haystack. The galaxy is a very, very big place, and with the inverse-square law, radio transmissions become almost undetectable within just a few light years unless extremely powerful, aimed right at us, and we are looking in exactly the right spot at the right time. The most likely explanation for the Fermi Paradox is that interstellar travel and communication is just too resource-intensive to do, leaving each sentient civilization as isolated castaways separated by distances that may as well be infinite.

David desJardins said...

The most likely explanation for the Fermi Paradox is that interstellar travel and communication is just too resource-intensive to do, leaving each sentient civilization as isolated castaways separated by distances that may as well be infinite.

I just don't see how that's plausible. Once you have self-replicating intelligent machines, with exponential growth, converting the whole solar system or the whole galaxy into whatever form you want is just a matter of time. And not that much time, on the scale we're talking about.

So you have to assume, more or less, that self-replicating machines are impossible. Is that plausible? It doesn't seem so to me. What's the obstacle?

Acacia H. said...

Read "Existence" - the last third of the novel actually focuses on part of this. Alternatively, you could read "Lungfish" (Dr. Brin's short story on the subject) but you'll get the general just of "Lungfish" with "Existence"

Rob H.

Paul451 said...

"In one - a series of short stories and novellas published in one of the digests - it turns out that anti-gravity and FTL drive are ludicrously easy. Most species discover the technology while still in the bronze age"

Harry Turtledove's "The Road Not Taken".

I always liked the "taste their own medicine" aspect. The aliens that try to invade Earth previously had free run of the galaxy because all rival races discovered anti-gravity even earlier, giving the "late bloomers" more advantage. But it never occurred to them what would happen if they met a race which took even longer.

"The other was a novel set in a galaxy divided between [...] Alphas are our descendants - the Betas are the descendants of humans taken as servants by aliens centuries ago."

This one I can't recall, and google isn't helping.

Anonymous said...

Based on global warming, my current estimate of "L" is 200, maybe 300 years.

(And I'm using the test for whether we *hear* from anyone -- radio-capable civilization.)

Given the other values, this makes our odds of hearing from anyone else out there really really really low, doesn't it?

All we have to do is have enough eco-collapse to stop sending radio signals. Given that we're screwing with our food chains, this is tremendously easy; human extinction is quite likely.

Tom Miller makes me reconsider this, though:
"The Fermi paradox may be more mundane than it looks. One of the problems with SETI is finding a needle in a haystack. The galaxy is a very, very big place, and with the inverse-square law, radio transmissions become almost undetectable within just a few light years unless extremely powerful, aimed right at us, and we are looking in exactly the right spot at the right time. "
This is a really interesting point. I thought, however, that our spray of radio signals into the ether was more detectable than that. (We don't have to be able to *read* them, just spot that they're not behaving 'naturally'). I'd love to see the numbers on radio signal decay.

Now, in response to everyone who expects a galactic empire:

Interstellar travel appears to be essentially non-viable, so it can be completely counted out. The only possibility, given our current knowledge of physics, is a generation ship. There are many, many ways to screw up generation ships, so they probably mostly die in deep space.

The generation ships aren't a very attractive thing to do anyway, since they take a lot of expensive resources and make them unrecoverable. We know now that any civilization which survives has to be recycling-based rather than extraction-based, which makes the entire concept even less attractive.

The few survivors probably fail to colonize their target worlds, since there are so many incompatibilities which can make that fail.

Exponential growth is not sustainable and self-replicating machines need energy and material resources.

Regarding the rarity-of-sapience question: Surely y'all have read "Swarm", by Bruce Sterling? The problem is that sapience is *not always an evolutionary advantage*, let alone the most valuable one. So it takes some tricky circumstances for it to evolve and thrive.

In contrast, the bacteria have a permanently successful evolutionary strategy: reproduce a whole lot and mutate really frequently. Most successful clade on Earth. If we find alien bacteria-like things on asteroids I would not be at all surprised any more.

David desJardins said...

What is the point of a "generation ship" once we can make intelligent machines that live forever? What does a "generation" even mean to an intelligence that lives forever?

Brendan said...

Quite late to the party, but...

Solving the Drake Equation will not, of itself, solve the Fermi Paradox. The reason is because the Drake Equation is simply a critical path representation for a single datapoint - the development of Human intelligence - which is presumed able to colonize, explore or interact with the galaxy. Block a critical path, and percolation can still occur via wide range of initial sources and pathways. Convergent evolution suggests that that may occur, just to name one element that could create a bypass in the Drake Equation.

What evidence does satisfy the Fermi Paradox to the positive? The literature suggests the following:

First contact
Signals that are not attributable to natural sources
Evidence of galactic engineering (or solar level engineering)
Artifacts in the solar system

None of these require "life as we know it" to provide the evidence. The torus's in Sundiver, or the dark-matter Xelee in Baxter's universe, or a myriad of alternative (speculated in science fiction) life forms could provide each of these pieces of evidence if they had the intelligence and will. So I find the emphasis on the "habitable zone", or the importance of the moon, or particular evolutionary critical jumps, as arguments to why intelligence has only occurred once, entirely misses the complexity of the paradox.

Here are two takes on solutions - both coming under the Singularity Solution approach, and both, even by science fiction standards, extremely speculative.

The first is that by the time a culture has the technical ability to send out reliable probes, they are only a few years/months/hours away from going into their singularity. Once they do, they, or a garbage collecting post-singularity being (and it only takes one) stops the probe years before they reach their first system. Why don't they go and explore/build K3 engineering complexes? Simple. The logical extension of Moore's law, which is a critical aim for singularity beings, is to drive mechanisms towards smaller "bits" so they can improve "brain power", until they utilise the limits of space (or spacetime) itself. Entirely speculative, I know, but not how well it sits with this fact: the acceleration of the expansion of the universe results in a net increase in the energy of the universe (it is not conserved, as it would be for a flat non-accelerating universe). Given a second potential aim of a singularity creature/race could be to prevent long-term "death" or loss of function by reversing or bypassing the consequences of entropy, kicking the universe into an accelerating mode could have been an elegant solution.

The second solution is that perhaps a singularity creature/race has sufficient power over time, that it can protect itself and its own development from external interference backwards in time.

Anonymous said...

Why we are so alone in the universe,this is impossible in’s always confused us for a long time.but if we solve the following qusetions.maybe we can find the answer obviously.
Can we read our memory from our brain by some kind of technology?and can we write it to a new brain of a new body we make it by genic technology or others.let’s assume it’s there are a series of questions coming.they are divided three parts.
Part one: personal
1:if your memory have been removed,who are you?
2:if your memory have been replaced another one’s memory,who are you?think this question carefully,you can image that when you wake up in every morning.
3:do you think the memory actually is your soul.( It doesn't matter if you don’t think so)
4:do you want to prolong your life by this way that read and write your memory?if not,how about the time you will die very soon.I think if I will died and I will try it because I have nothing could be lost.
Part two:Human
1:if someone among us want prolong their life by the way read&write memory,does their life have huge advantage to normal person.because they are immortal,they can choose their body and etc.
2:if 1% person in the world want prolong their life by this way,can they finally replace all human’s life form like now .
3:if you can be immortal and change your body if you live in the world a few thousands years after.what do you think about the meaning of the live.I have thought this question and I get a result that we will become observer from participator for nature.just watch,hear and feel the running of nature.
4:can you image where the genic technology or other technology lead us to.the standard of body we choose is more strong, pretty or simple but can receive enough information from the nature that we can feel it better to be a observor.
Part three: nature
1:why every one in the earth thought they have soul and the soul is they real one had ever seen or heard it.whatever they have different faith,education,nationality or etc.why this theory is infused into every one’s brain?can we define it is instinct.and every intelligent creature in the universe like or better than human have this instinct?
2:if we calculate the length of human civilization from the birth of words.there have already been a few thousands years till now.let’s assume we will be observer within 5000 years.(it’s a very long time for human).so current human civilization is totally ten thousands years. The extinction of the Dinosaurs had occurred 66 million years ago.then you can image a scene that you have a book have 6.6 thousands pages.the kind of civilization of human just is one page among it.and we look for it in infinite space and time.the chance that we meet is very impossible.
3:we all aware not every creature can be intelligent like human.human thing just is occasionaly maybe other “human” had appeared in the earth in other page.we just dose alien.the civilization like human that we look for just is a transition stage from participator to observer,the length is very short for the universe.and if we become observer,we just feel the running of the nature.don’t want to interfere in it.
4:if we don’t like this future,can we stop it?I don’t think so.because no one can stop the science go forward.and there must have someone to try it when the read-mind technology is matured.
5:Is there other way we can go?no,because the memory is the only answer for the soul,not DNA,face or something else.and the soul is human real one can deny if we can ,we must do

SteveMcK said...

I've actually either never under stood "Fermi's Paradox" or just think it's absurd.

All the advances of the last 200 years, and we just detected our first PLANET outside our solar system in the last decade?

How are we supposed to recognize any "structures" he's talking about?

And why would they use radio waves? More then likely they became obsolete a long time ago. Either that, or because of the vast distances, haven't reached us yet.

Or have reached us, but since it originated from a wholly alien intelligence, we couldn't decode it or even recognize it.

I don't see "Fermi's Paradox as any problem whatsoever.