Category: <span>Fermi’s Paradox</span>

What “The Expanse” Can Teach Us about Fermi’s Paradox

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This post is going to draw fairly extensively from The Expanse series. It contains definite spoilers for anyone who hasn’t made it through book 3 of the series or season 3 of the TV show. Also the post will have some vague allusions to what happens after that. (I have not personally had the chance to watch the TV show much past season 1, so the exact amount I’m spoiling there might be more than I think.) 

You have been warned.


This blog has been fascinated by Fermi’s Paradox since its inception. As such I’m always interested in the explanations science fiction authors create in the course of tackling the paradox in their books. Some explanations are fascinating and thought provoking, some are implausible and lazy. The explanation given by the Expanse Series, by James S. A. Corey, is fortunately one of the former.

We get Corey’s answer at the end of Abaddon’s Gate, the third book in the series. As it turns out there was someone else out there, and they created a empire of over 1300 planets and knit them together with a network of gates. Earth was supposed to be one of those planets, but the device which would have created the gate (and dramatically hijacked all life on Earth in the process) was captured by Saturn’s gravity and never made it to its final destination.

Eventually people find this device and hilarity ensues. Okay not really, the device (what the series calls the protomolecule) actually turns people into horrible zombie-like creatures who eventually merge with each other into something even more horrible, which then eventually turns into the “Sol Gate” humanity’s very own connection to the ring network. You may have noticed earlier that I said that there was something out there. Well, when the humans travel through the ring they find out that the aliens who built the gates have vanished. Nor is the reason for their disappearance entirely mysterious. It is soon discovered that they were killed off by something even bigger and nastier. 

From the perspective of the series the creation of the gate is good and bad. It’s good because now humans have easy access to hundreds of new, habitable worlds. It’s bad because not only do they know that there exists some other awesomely powerful entity—an entity which is horribly, and seemingly blindly malevolent, something like Lovecraft’s description of the elder gods—but they also may have just brought themselves to the attention of this entity.

As I mentioned this all comes out at the end of book three. The series just barely concluded with book 9 (review coming soon!) So based on this mix of good and bad news what do you imagine the humans do in the subsequent books? Well, and I think Corey predicts this accurately, they spend all of their time on the bounty of the 1300+ systems they’ve just discovered, and almost none of it on the giant, horrible elder gods lurking in the shadows. Now to be fair, they’ve got a lot of problems to deal with other than the elder gods. The animosity between Earth, Mars and the Belters has not gone away just because there’s a bunch of new worlds, in fact if anything the discovery has inflamed tensions. But still one would hope that should we be confronted with this situation in actuality that we would spend more time on the giant, horrible alien problem than the people in the book do, but maybe not.

There is however one person in the books who’s different. One person who will stop at nothing to ensure the survival of humanity. This is Winston Duarte. If you have read many books like this, you may have already guessed that he’s the bad guy. Whether this would be so in reality is not the point of this post, and to be clear, in the context of the books he does end up doing some very bad things. No, the point of this post is to imagine what we might do if we were Duarte. If we decided that the problem of the missing aliens was really the biggest problem humanity faces. 

Of course to a certain extent there are such people, people who are really interested in identifying and dealing with existential issues, because if we don’t we may not be around to deal with anything else. I’ve reviewed some of their books, for example: Global Catastrophic Risks by Nick Bostrom and Milan Ćirković and The Precipice by Toby Ord. And I will continue to review and read these books. I think they touch on one of the most important subjects people can be thinking about. But while reading the final book of The Expanse I was struck by the similarity between Duarte’s situation and our own. And I wanted to use it as a springboard to revisit the profound implications of Fermi’s Paradox, and how it’s easy to understand those implications when it’s fiction, but far harder when it’s reality.


The insight which prompted me to write this post was the realization that there are a lot of similarities between our position and the position of the humans who have just discovered the gates. There were many, many years when neither was even aware of the problem, and then suddenly, in their case, and almost as suddenly, in our case, we both realized that we had a big problem. Both of us have every reason for believing that there should be aliens out there. And as it turns out (thus far) the rest of the universe is empty.

Of course there are obviously some differences. To begin with you may think that our situation is not as bad as the one Duarte is focused on, but I’m not sure that’s the case. He has the advantage of knowing exactly what the problem is: there is some sort of Lovecraftian elder god which eradicates any civilization above a certain level of technology. Of course this is a very big problem, possibly insoluble, but at least he knows where to direct his attention and his energy. And while it is true that nearly everyone else in the books seems to be ignoring the problem. At least they’re aware of it. And when the time comes it doesn’t take much to get them to throw enormous resources at it. On the other hand, most people today aren’t even aware that there is a problem, if they are aware of it they may wonder whether it’s appropriate to even call it a “problem”, and if they grant all of that, there’s still very little agreement on what sort of problem it might be.

To get more concrete, sitting on a shelf in front of me is a book which contains 75 explanations for Fermi’s paradox, and even this collection of 75 explanations doesn’t cover all of the possibilities. Duarte only has to concern himself with one of those explanations: malevolent aliens, and not even malevolent aliens as a general concept, but rather a specific malevolent alien whose existence has already been demonstrated beyond any reasonable doubt. This is not to say that all of the questions posed by the paradox have been answered. For example, did the ring builders really wipe out all other life before being wiped out themselves? But as far as Duarte is concerned the part that matters has been solved, and now he just has to deal with the problems arising from the reality of that solution. And he has lots of options for doing just that. The elder gods might have left clues as to their motivations; there might also be precautions he could take; experiments he could run; or at least data he could collect. 

Duarte doesn’t have to worry about other possible solutions. He doesn’t have to worry that all intelligent aliens destroy themselves in a nuclear war so humans will as well. Or at least he doesn’t have to worry about this nearly as much as we do. Humans are now on hundreds of worlds, and have gone hundreds of years without such a war. He doesn’t have to worry about the difficulties intelligent species might encounter in making it off their home planet in the first place. Humans (in The Expanse) have already shown that can be done as well. Nor does he have to worry about interstellar distances, not only has the gates made this point moot, but even without the gates a major plot point of the first few books is that the Mormons (Go team!) are preparing to leave the solar system in a generational ship. And the list of things he no longer has to worry about goes on and on beyond these examples.

On the other hand, when we contemplate the silent universe we have to consider all 75 solutions, while also being aware of the fact that this list might not be exhaustive, we have probably overlooked some of the possibilities, perhaps even the correct one. 

Some of the potential solutions to the paradox are better for us than the elder gods of The Expanse. Some are worse. You might take issue with the idea that anything could be worse than implacably hostile, nearly omnipotent super aliens, but I disagree. There’s always some chance that we could avoid, placate, or defeat the other aliens. In fact, the chances of avoiding them seem particularly high, since we already managed to do so for tens of thousands of years. But if we consider the entire universe of possible solutions, there are explanations where our chances of survival are much, much lower. As an example, what if the answer to Fermi’s paradox is something inherent to intelligence, or technological progress, or biological evolution itself? Something that hasn’t merely defeated one set of aliens (as was the case with The Expanse) but has defeated all of the potential aliens. Something which because of this inherency will almost certainly defeat us as well.

Back in 1998 Robin Hanson gave a name to this idea of something that defeats all potential aliens, he called it the Great Filter. This is the idea that there is something which prevents intelligent life from developing and spreading across the galaxy in an obvious fashion. Some hurdle which makes it difficult for life to develop in the first place, or which makes it difficult for life, once developed, to achieve intelligence, or which makes it difficult for intelligent life to become multiplanetary. Since Hanson came up with the idea, people have obviously wondered what that hurdle or filter might be, but more importantly they’ve wondered, is it ahead of us or behind us? 

Pulling all of this together, I would say the idea that the Great Filter is ahead of us, and not merely ahead of us, but nearby—a built in consequence of technological progress—is a far scarier solution to the paradox than even the elder gods of The Expanse. The only thing that mitigates the scariness of this solution is the fact that it’s not certain. There is some probability that the true explanation for the paradox is something else. 

It is this uncertainty, and not the magnitude of the catastrophe which represents the key difference between Duarte’s situation and ours.


This is not the first time this blog has covered potential catastrophes with uncertain probabilities. In fact it might be said to represent the primary theme of the blog. So how do you handle this sort of thing if you’re a real, modern day Duarte, rather than the fictional one a couple of centuries in the future? How do you proceed if the threat isn’t certain, if there’s no data to collect, no experiments to run, no motivations to probe? Are there at least precautions one could take?

There might be, but most people who do end up focusing on this sort of thing spend far more time trying to assess the probabilities of the various catastrophes, the various solutions to the paradox, than in trying to understand and mitigate those catastrophes. And frequently the conclusion they come to is that one can explain the paradox without resorting to catastrophic explanations. It can be explained entirely by the fact that we’re extraordinarily lucky. And I mean EXTRA-odinarily lucky. Since I’ve already alluded to Stephen Webb’s book If the Universe Is Teeming with Aliens… Where Is Everybody?: Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life we might as well look at the account he gives of our unbelievable luck.

I did a very detailed breakdown of it in a previous post, but in essence it assumes that there are 1 trillion planets in the galaxy and out of the trillion places where it could have happened Earth was the only place where life did happen.

That we were lucky enough to be on a planet in the galactic habitable zone.

…which also orbits a sun-like star

…in the habitable zone of that same star

…which turned that luck into life

…that this life was lucky enough to avoid being wiped out prematurely

…developing from single-celled to multicellular life

…and not merely multicellular life, but intelligent, tool-using, mathematical life.

In other words we won the lottery, but actually we did better than that. You actually have a 1 in 300 million chance of winning even a really big lottery, like the Mega Millions. 1 in a trillion is actually 3,000 times less likely even than that. 

This explanation and similar explanations for the paradox are given the label “Rare Earth”, and I’ll admit that I’m probably not the best person to talk about them because they strike me as being optimistic to the point of delusion. Similar to the people in The Expanse who look at the gates and only see the hundreds of inhabitable worlds, not the omnicide of the aliens who built the gates in the first place. Yes, it’s possible that Earth, alone out of the trillion planets in the galaxy, has managed to get past the Great Filter. That some species on some planet was going to get lucky, and it just happened to be us. That, now, as the beneficiaries of this luck, a glorious transhuman future stretches out in front of us, where everything just keeps getting better and better. Certainly this vision is attractive, the question is whether it’s true. Of course it’s impossible to know, but many people have decided to treat it as such. Is this because the body of evidence for this position is overwhelming? Or is it because it’s comforting? My money is on the latter. But we’re not looking for comfort. We’re not interested in the hundreds of habitable worlds. We’re Duarte and we’re focused on the danger. 

This is not to say, in our role as Duarte, that we entirely dismiss the possibility of a Rare Earth explanation. Only that such an explanation is being adequately handled by other people. Duarte doesn’t need to focus on how to speed up the colonization of the newly discovered worlds. Everybody else is doing that. He’s focused on the paradox, and the potential danger. He doesn’t care whether there are a trillion planets in the Milky Way or only 800 billion. He doesn’t worry about knowing the minutia of astrobiology. He’s just worried about preventing humanity’s extinction, and in that effort, spending all of your time debating probabilities is just a distraction. 

Why? Well to begin with, as we’ve seen with people making the Rare Earth argument, people will ignore probabilities when it suits them. And if they were really concerned about assigning probabilities to things, what probability would they assign to the ideas I’m worried about, the ideas I’ve talked about over the course of this blog? For example, the possibility that intelligence inevitably creates the means of its own destruction. Less than 1 in a billion? Less than 1 in a thousand? And yet for reasons of sophistry and comfort they will proudly claim that Fermi’s paradox has been dissolved because we happen to be the result of odds which are much longer than that. 

Second, and even more importantly, assigning such probabilities is difficult to the point of basically being worthless. We have no idea how hard it is for life to arise on an earth-like planet, and still less of an idea how hard it is for that life to progress from its basic form to human-level intelligence. And if, despite these difficulties, we decide that we’re going to persist in trying to assign probabilities, it would seem easier and more productive to try to assign probabilities to the potential catastrophes rather than buttressing our illusion of safety. It’s easier because while we have no other examples of complex life developing we have plenty of examples of complex civilizations collapsing (for examples see the Fall of Civilizations Podcast) And it’s more productive because even if everyone who believes in the rare earth explanation is absolutely correct, we could still be in trouble from our own creations. 


If the previous parts have been enough to make you sympathetic to the “Duarte viewpoint”, and you’re ready to move from a discussion of probabilities to a discussion of precautions, then the obvious question is what precautions should we be taking?

Here I must confess that I don’t actually know. Certainly there’s the general admonition to gradualism. Also I think we should be attempting to reduce fragility in general. And to the extent I have advice to give on those topics, I have mostly already given it in other posts. What I was hoping to do in this post was to make the whole situation easier to understand by way of analogizing it to the situation in The Expanse and in that effort there are a couple of points I would still like to draw your attention to.

As I said I’m not sure what precautions we should be taking. But I am sure we have more than enough people focused on “colonizing new worlds” and not nearly enough focused on “scary elder gods”. Additionally we seem unwilling to make many tradeoffs in this area. Lots of people give lip service to the terrible power of the elder gods, but almost no one is willing to divert resources from the colonization project in order to better fight, or even just understand their awful power.

Finally there’s the objection I think most people will have, particularly those who’ve read the books, or who are otherwise familiar with totalitarianism. If we do manage to get more Duartes isn’t it possible or even likely that they will go too far? That the neo-neo-luddites will throw the baby out with the bathwater? If the pandemic has taught us anything it’s that reasonable people can disagree about how threatening something is, and whether a given response is appropriate for that threat.

Obviously such an extreme outcome is possible, but thus far it isn’t even clear that we’re going to ban gain of function research despite there being at least some chance that it was responsible for the pandemic. If that’s where we’re currently at on managing the unexpected harms of technological progress I don’t think we’re in much danger of going too far anytime soon. 

I suppose the big takeaway from this post is that we need more Duarte’s. I suspect that there are a lot of people who read The Expanse and think: Those foolish individuals! They’re so focused on colonizing the habitable planets, when really they should be focused on the huge malevolent aliens that wiped out the last civilization. If you are one of the people that comes away with this impression then you should come away with precisely the same impression when viewing our own situation

It’s possible that someone out there is wondering what they could get me for Christmas. Well mostly I want the ability to ruthlessly crush my enemies, just like everyone. But if that seems too difficult to arrange, consider donating

Eschatologist #7: Might Technology = Extinction?

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One of the great truths of the world is that the future is unpredictable. This isn’t a great truth because it’s true in every instance. It’s a great truth because it’s true about great things. We can’t predict the innovations that will end up blessing (or in any event changing) the lives of millions, but even more importantly we can’t predict the catastrophes that will end up destroying the lives of millions. We can’t predict wars or famines or plagues—as was clearly demonstrated with the recent pandemic. And yet on some level despite the impossibilities of foretelling the future we must still make an attempt.

It would be one thing if unpredicted catastrophes were always survivable. If they were tragic and terrible, but in the end civilization, and more importantly humanity, was guaranteed to continue. Obviously avoiding all tragedy and all terror would be ideal, but that would be asking too much of the world. The fact is even insisting on survivability is too much to ask of the world, because the world doesn’t care. 

Recognizing both the extreme dangers facing humanity, as well as the world’s insouciance, some have decided to make a study of these dangers, a study of extinction risks, or x-risks for short. But if these terminal catastrophes are unpredictable what does this study entail? For many it involves the calculation of extreme probabilities—is the chance of extinction via nuclear war 1 in 1,000 over the next 100 years or is it 1 in 500? Others choose to look for hints of danger, trends that appear to be plunging or rising in a dangerous direction or new technology which has clear benefits, but perhaps also, hidden risks. 

In my own efforts to understand these risks, I tend to be one of those who looks for hints, and for me the biggest hint of all is Fermi’s Paradox, the subject of my last newsletter. One of the hints provided by the paradox is that technological progress may inevitably carry with it the risk of extinction by that same technology

Why else is the galaxy not teeming with aliens

This is not to declare with certainty that technology inevitably destroys any intelligent species unlucky enough to develop it. But neither can we be certain that it won’t. Indeed we must consider such a possibility to be one of the stronger explanations for the paradox. The recent debate over the lab leak hypothesis should strengthen our assessment of this possibility. 

If we view any and all technology as a potential source of danger then we would appear to be trapped, unless we all agree to live like the Amish. Still, one would think there must be some way of identifying dangerous technology before it has a chance to cause widespread harm, and certainly before it can cause the extinction of all humanity! 

As I mentioned already there are people studying this problem and some have attempted to quantify this danger. For example here’s a partial list from The Precipice: Existential Risk and the Future of Humanity by Toby Ord. The odds represent the chance of that item causing humanity’s extinction in the next 100 years.

  • Nuclear War                       ~1 in 1000
  • Climate Change                 ~1 in 1000
  • Engineered Pandemics     ~1 in 30
  • Out of control AI                ~1 in 10

You may be surprised to see nuclear war so low and AI so high, which perhaps is an illustration of the relative uncertainty of such assessments. As I said, the future is unpredictable. But such a list does provide some hope, maybe if we can just focus on a few items like these we’ll be okay? Perhaps, but I think most people (though not Ord) overlook a couple of things. First, people have a tendency to focus on these dangers in isolation, but in reality we’re dealing with them all at the same time, and probably dozens of others besides. Second it probably won’t be the obvious dangers that get us—how many people had heard of “gain of function research” before a couple of months ago?

What should we make of the hint given us by Fermi’s Paradox? How should we evaluate and prepare ourselves against the potential risks of technology? What technologies will end up being dangerous? And what technologies will have the power to save us? Obviously these are hard questions, but I believe there are steps we can take to lessen the fragility of humanity. Steps which we’ll start discussing next month…

If the future is unpredictable, how do I know that I’ll actually need your donation. I don’t, but money is one of those things that reduce fragility, which is to say it’s likely to be useful whatever the future holds. If you’d like to help me, or indeed all of humanity, prepare for the future, consider donating.

Eschatologist #6: UFOs, Eschatology and Fermi’s Paradox

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UFOs have been in the news a lot recently. This is not the first time this has happened — the period immediately after World War II featured quite a bit of excitement about UFOs with some describing it as full on “mania”. But while this is not the first time UFOs have been in the news it is probably the first time reported sightings have been treated so sympathetically. The Washington Post recently announced, “UFOs exist and everyone needs to adjust to that fact”, and declared “It’s time to take UFOs seriously. Seriously.

Of course, the existence of UFOs does not necessarily imply the existence of aliens, but that’s the connection everyone wants to make. In many respects this is a hopeful connection. It would mean that we’re not alone. As it becomes increasingly obvious how badly humanity bungled 2020, the idea that there are superior beings out there is no longer a source of dread but of comfort.

I’m very doubtful that the UFOs are aliens. First for reasons of natural skepticism, second, it isn’t too difficult to find reasonable, mundane explanations for the videos and finally for many subtle reasons I don’t have time to get into, but which boil down to the suspiciously convenient timing of the craft’s discovery and their all too human behavior. They’re not alien enough. 

Accordingly, I would contend that the videos are probably not evidence of aliens. They don’t answer the question of whether we’re alone or not. But that doesn’t mean the question is not tremendously important. But if the videos don’t answer the question is there some other way of approaching it?

In 1950, during the last big UFO mania, Enrico Fermi decided to approach it using the Copernican Principle. Copernicus showed that the Earth is not the center of the universe. That our position is not special. Later astronomers built on this and showed that nothing about the Earth is special. That it’s an average planet, orbiting an average star in an average galaxy. Fermi assumed this also applies to intelligent life. If the Earth is also average in this respect then there should not only be other intelligent life in the universe, i.e. aliens, but some of these aliens should be vastly more advanced than we are. The fact that we haven’t encountered any such aliens presents a paradox, Fermi’s Paradox.

In the decades since Fermi first formulated the paradox it has only become more paradoxical. We now know that practically all stars have planets. That there are billions of earthlike planets in our galaxy, some of which are billions of years older than Earth. And that life can survive even very extreme conditions. So why haven’t we encountered other intelligent life? Numerous explanations have been suggested, from a Star Trek-like Prime Directive which prevents aliens from contacting us, to the idea that advanced aliens never leave their planet because they can create perfect virtual worlds.

Out of all of the many potential explanations, Robin Hanson, a polymath professor at George Mason University, noticed that many could be boiled down to something which prevents the development of intelligent life or which prevents it from surviving long enough to be noticable. He lumped all these together under the heading of Great Filter. One possibility for this filter is that intelligent life inevitably destroys itself. Certainly when we gaze at the modern world this idea doesn’t seem far-fetched.

Accordingly, Fermi’s Paradox has profound eschatological implications — ramifications for the final destiny of humanity. If the Great Filter is ahead of us, then our doom approaches, sometime between now and when we develop the technology to make our presence known to the rest of the galaxy. In other words, soon. On the other hand, if the Great Filter is behind us then we are alone, but also incredibly special and unique. The only intelligent life in the galaxy and possibly beyond. 

Consequently, whatever your own opinions on the recent videos, they touch on one of the most profound questions we face: does humanity have a future? Because when we look up into the night sky at its countless stars we’re seeing that future, in the billions of Earths far older than our own. And as long as they’re silent, then, after a brief moment of light and civilization, our own future is likely to be just as silent.

I think some people would like it if I were silent, but if you’re reading this I assume you’re not one of them. If your feelings go beyond that and you actually like what I say, consider donating.

Don’t Don’t Fear the Filter

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On the occasion of the end of the old decade and the beginning of the new, Scott Alexander of Slate Star Codex, wrote a post titled What Intellectual Progress Did I Make in the 2010s. I am generally a great admirer of Alexander, in fact, though I don’t mention it often in this space I have been turning every one of his blog posts into an episode in a podcast feed since late 2017. In particular, I am impressed by his objectivity, his discernment, and dispassionate analysis. But in this particular post he said something which I take strong exception to:

In terms of x-risk: I started out this decade concerned about The Great Filter. After thinking about it more, I advised readers Don’t Fear The Filter. I think that advice was later proven right in Sandberg, Drexler, and Ord’s paper on the Fermi Paradox, to the point where now people protest to me that nobody ever really believed it was a problem.

I am not only one of those who once believed it was a problem, I’m one who still believes it’s a problem. And in particular it’s a problem for rationalists and transhumanists, which are exactly the kind of people Alexander most often associates with and therefore most likely to be the people who now protest that nobody ever really believed it was a problem. But before we get too deep into things, it would probably be good to make sure people understand what we’re talking about.

Hopefully, most people reading this post are familiar with Fermi’s Paradox, but for those who aren’t, it’s the apparent paradox between the enormous number of stars and the enormous amount of time they’ve existed, and the lack of any evidence for civilizations, other than our own, arising among those billions of stars over those billions of years. Even if you were already familiar with the paradox you may not be familiar with the closely related idea of the Great Filter which is an attempt to imagine the mechanism behind the paradox, and in particular when that mechanism might take effect. 

Asking what prevented anyone else from getting as far, technologically, as we’ve gotten, or most likely a lot father is to speculate about the Great Filter. It can also take an inverted form, when someone asks what makes us special. But either way, the Great Filter is that thing which is either required for a detectable interstellar presence or which prevents it. And what everyone wants to know is whether this filter is in front of us or behind us. There are many reasons to think it might be ahead of us. But most people who consider the question hope that it’s behind us, that we have passed the filter. That we have, one way or another, defeated whatever it is which prevents life from developing and being detectable over interstellar distances.

Having ensured we’re on the same page we can return to Alexander’s original quote above, where he mentions two sources for his lack of concern. First his own post on the subject: “Don’t Fear the Filter”, and second the Sandler, Drexler, Ord paper on the paradox.


Let’s start with his post. It consists of him listing four broad categories of modern risks which people hypothesis might represent the filter. Which would indicate both that the filter is ahead of us, and that we should be particularly concerned about the risk in question. Alexander then proceeds to demonstrate that these risks as unlikely to be the Great Filter. As I said, I’m a great admirer of Alexander, but he makes several mistakes in this post.

To begin with, he makes the very mild mistake of dismissing anything at all. Obviously this is eminently forgivable, he’s entitled to his opinion and he does justify that opinion, but given how limited our knowledge is in this domain, I think it’s a mistake to dismiss anything. To return to my last post, if someone had come to Montezuma in 1502 when he took the throne and told him that strangers had arrived from another world and that within 20 years he would be dead and his empire destroyed, and that in less than 100 years 95% of everyone in the world (his world) would be dead, he would have been dismissed as a madman, and yet that’s exactly what happened.

Second, his core justification for arguing that we shouldn’t fear the filter is that it has to be absolutely effective at preventing all civilizations (other than our own) from interstellar communication. He then proceeds to list four things which are often mentioned as being potential filters, but which don’t fulfill this criteria of comprehensiveness, because these four things are straightforward enough to ameliorate that some civilization should be able to do it even if ours ends up being unable to. This is a reasonable argument for dismissing these four items, but in order to decisively claim that we shouldn’t “fear the filter”, he should at least make some attempt to identify where the filter actually is, if it’s not one of the things he lists. To be charitable, he seems to be arguing that the filter is behind us. But if so you have to look pretty hard to find that argument in his post.

This takes me to my third point. It would be understandable if he made a strong argument for the filter being behind us, but really, to credibly banish all fear, even that isn’t enough. You would have to make a comprehensive argument, bringing up all possible candidates for a future filter, not merely the ones that are currently popular. It’s not enough to bring up a few x-risk candidates and then dismiss them for being surmountable. The best books on the subject, like Stephen Webb’s If the Universe Is Teeming with Aliens … WHERE IS EVERYBODY?: Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life (which I talked about here) and Milan M. Ćirković’s The Great Silence: Science and Philosophy of Fermi’s Paradox (which I talked about here and my personal favorite book on the topic) all do this. Which takes me to my final point.

People like Ćirković and Webb are not unaware of the objections raised by Alexander. Both spend quite a bit of time on the idea that whatever is acting as the filter would have to be exceptionally comprehensive, and based on that and other factors they rate the plausibility of each of the proposed explanations. Webb does it as part of each of his 75 entries, while Ćirković provides a letter grade for each. How does he grade Alexander’s four examples?

  1. Nuclear War: Alexander actually includes all “garden variety” x-risks, but I’ll stick to nuclear war in the interests of space. Ćirković gives this a D.
  2. Unfriendly AI: Ćirković places this in category of all potential self-destructive technologies and gives the entire category a D+.
  3. Transcendence: Ćirković gives this a C-/F. I can’t immediately remember why he gave it two grades, nor did a quick scan of the text reveal anything. But even a C- is still a pretty bad grade.
  4. The Dark Forest (Exterminator aliens): Ćirković gives this a B+, his second highest rating out of all candidates. I should say I disagree with this rating (see here) for much the same reasons as Alexander.

With the exception of the last one, Ćirković has the same low opinion of these options as Alexander. And if we grant that Alexander is right and Ćirković is wrong on #4 which I’m happy to do since I agree with Alexander. Then the narrow point Alexander makes is entirely correct, everyone agrees that these four things are probably not the Great Filter, but that still leaves 32 other potential filters if we use Ćirković’s list, and north of 60 if we use Webb’s list. And yes, some of them are behind us (I’m too lazy to separate them out) but the point is that Alexander’s list is not even close to being exhaustive.

(Also, any technologically advanced civilization would probably have to deal with all these problems at the same time, i.e. if you can create nukes you’re probably close to creating an AI, or exhausting a single planet’s resources. Perhaps individually they should each get a D grade, but what about the combination of all of them?)

If I was being uncharitable I might accuse Alexander of weak-manning arguments for the paradox and the filter, but I actually don’t think he was doing that, rather my sense is that like many people with many subjects, despite his breadth of knowledge elsewhere, he doesn’t realize how broad and deep the Fermi’s Paradox discussion can get, or how many potential future filters there are which he has never considered.


Most people would say that the strongest backing for Alexander’s claim is not his 2014 post, but rather the Sandler, Drexler, and Ord study (SDO paper).

(Full disclosure: In discussing the SDO paper I’m re-using some stuff from an earlier post I did at the time the study was released.)

To begin with, one of Alexander’s best known posts is titled Beware the Man of One Study, where he cautions against using a single study to reach a conclusion or make a point. But isn’t that exactly what he’s doing here? Now to be fair, in that post he’s mostly cautioning against cherry picking one study out of dozens to prove your point. Which is not the case here, mostly because there really is only this one study, but I think the warning stands. Also if you were going to stake a claim based on a single study the SDO paper is a particularly bad study to choose. This is not to say that the results are fraudulent, or that the authors made obvious mistakes, or that the study shouldn’t have been published, only that the study involves throwing together numerous estimates (guesses?) across a wide range of disciplines, where, in most cases direct measurement is impossible. 

The SDO paper doesn’t actually center on the paradox. It takes as its focus Drake’s equation, which will hopefully be familiar to readers of this blog. If not, basically Drake’s equation attempts to come up with a guess for how many detectable extraterrestrial civilizations there might be by determining how many planets might get through all the filters required to produce such a civilization (e.g. How many planets are there? What percentage have life? What percentage of that life is intelligent? etc.). Once you’ve filled in all of these values the equation spits out an expected value for the number of detectable civilizations, which generally turns out to be reasonably high, and yet there aren’t any, which then brings in the paradox.

The key innovation the SDO paper brings to the debate is to map out the probability distribution one gets from incorporating the best current estimates for every parameter in the equation, and pointing out that this distribution is very asymmetrical. We’re used to normal distributions (i.e. bell curves) in which the average and the most likely outcome are basically the same thing, but the distribution of potential outcomes when running numbers through Drake’s equation are ridiculously wide and on top of that not normally distributed which means, according to the study, the most probable situation is that we’re alone, even though the average number of expected civilizations is greater than one. Or to borrow the same analogy Alexander does:

Imagine we knew God flipped a coin. If it came up heads, He made 10 billion alien civilization. If it came up tails, He made none besides Earth. Using our one parameter Drake Equation, we determine that on average there should be 5 billion alien civilizations. Since we see zero, that’s quite the paradox, isn’t it?

No. In this case the mean is meaningless. It’s not at all surprising that we see zero alien civilizations, it just means the coin must have landed tails.

As I said, it’s an innovative study, and a great addition to the discussion, but I worry people are putting too much weight on it, because the paper does some interesting and revealing math and it looks like science, when, as Michael Crichton pointed out in a famous speech at Stanford, Drake’s equation is most definitely not science. (Or if you want this same point without climate change denial you could check out this recent post from friend of the blog Mark.) The SDO paper is a series of seven (the number of terms in Drake’s equation) very uncertain estimates, run through a monte carlo simulator, and I think there’s a non-trivial danger of garbage in garbage out. But at a minimum I don’t think the SDO paper should generate the level of certainty Alexander claims for it. 

If this is right – and we can debate exact parameter values forever, but it’s hard to argue with their point-estimate-vs-distribution-logic – then there’s no Fermi Paradox. It’s done, solved, kaput. Their title, “Dissolving The Fermi Paradox”, is a strong claim, but as far as I can tell they totally deserve it.

His dismissal of parameter values is particularly hard to understand. (Unless he thinks current estimate ranges will basically continue to hold forever.) The range of values determines the range of the distribution. Clearly there are distributions where the SDO paper’s conclusion no longer holds. All it would take to change it from “mostly likely alone”, to “there should be several civilizations” would be a significant improvement in any of the seven terms or a minor improvement in several. Which seems to be precisely what’s been happening.


From 1961 when Drake’s equation was first proposed, until the present day, our estimates of the various terms has gotten better, and as our uncertainty decreased it almost always pointed to life being more common.

One great example of this, is the current boom in exoplanet discovery. This has vastly reduced the uncertainty in the number of stars with planets. (Which is the second term in the equation.) And the number of planets which might support life (the third term). The question is, as uncertainty continues to be reduced in the future, in which direction will things head? Towards a higher estimate of detectable civilizations or towards a lower estimate? The answer, so far as I can tell, is that every time our uncertainty gets less it updates the estimate in favor of detectable civilizations being more common. There are at least three examples of this:

  1. The one I just mentioned. According to Wikipedia when Frank Drake first proposed his equation, his guess for the fraction of stars with planets was ½. After looking at the data from Kepler, our current estimate is basically that nearly all stars have planets. Our uncertainty decreased and it moved in the direction of extraterrestrial life and civilizations being more probable.
  2. The number of rocky planets, which relates to the term in the equation for the fraction of total planets which could sustain life. We used to think that rocky planets could only appear seven billion years or so into the lifetime of the universe. Now we know that they appeared much earlier. Once again our uncertainty decreased, and it did so in the direction of life and civilizations being more probable.
  3. The existence of extremophiles. We used to think that there was a fairly narrow band of conditions where life could exist, and then we found life in underwater thermal vents, in areas of extreme cold and dryness, in environments of high salinity, high acidity, high pressure, etc. etc. Yet another case where as we learned more, life became more probable, not less.

But beyond all of this, being alone in the galaxy/universe reverses one of the major trends in science. The trend towards de-emphasizing humanity’s place in creation.

In the beginning if you were the ruler of a vast empire you must have thought that you were the center of creation. Alexander the Great is said to have conquered the known world. I’m sure Julius Caesar couldn’t have imagined an empire greater than Rome, but I think Emperor Yuan of Han would have disagreed.

But surely, had they know each other, they could agreed that between the two of them they more or less ruled the whole world? I’m sure the people of the Americas, would have argued with that. But surely all of them together could agree that the planet on which they all lived was at the center of the creation. But then Copernicus comes along, and says, “Not so fast.” (And yes I know about Aristarchus of Samos.)

“Okay, we get it. The Earth revolves around the Sun, not the other way around. But at least we can take comfort in the fact that man is clearly different and better than the animals.”

“About that…” says Darwin


“Well at least our galaxy is unique…”

“I hate to keep bursting your bubble, but that’s not the case either,” chimes in Edwin Hubble.

At every step in the process when someone has thought that humanity was special in any way someone comes along and shows that they’re not. It happens often enough that they have a name for it, The Copernican Principle (after one of the biggest bubble poppers). Which, for our purposes, is interchangeable with the Mediocrity Principle. Together they say that there is nothing special about our place in the cosmos, or us, or the development of life. Stephen Hawking put it as follows:

The human race is just a chemical scum on a moderate-sized planet, orbiting around a very average star in the outer suburb of one among a hundred billion galaxies.

This is what scientists have believed, but if we are truly the only intelligent, technology using life form in the galaxy or more amazingly the visible universe, then suddenly we are very special indeed. 


As I mentioned the SDO paper, despite its title, is only secondarily about Fermi’s Paradox. It’s actually entirely built around Drake’s Equation, which is one way of approaching the paradox, but one that has significant limitations. As Ćirković says, in The Great Silence:

In the SETI [Search for Extraterrestrial Intelligence] field, invocation of the Drake equation is nowadays largely an admission of failure. Not the failure to detect extraterrestrial signals—since it would be foolish to presuppose that the timescale for the search has any privileged range of values, especially with such meagre detection capacities—but of the failure to develop the real theoretical grounding for the search.

Ćirković goes on to complain that the equation is often used in a very unsophisticated fashion, and in reality it should be “explicated in terms of relevant probability distribution functions” and to be fair, that does appear to be what the SDO paper is attempting, whether they’re succeeding is a different matter. Ćirković seems to be suggesting a methodology significantly more complicated than that used by the study. But, this is far from the only problem with the equation. The biggest is that none of the terms accounts for interstellar travel by life and civilizations to planets beyond those where they arose in the first place. 

The idea of interstellar colonization by advanced civilizations is a staple of science fiction and easy enough to imagine, but most people have a more difficult time imagining that life itself might do the same. This idea is called panspermia, and from where I sit, it appears that the evidence for that is increasing as well. On the off chance that you’re unfamiliar with the term, panspermia is the idea that life, in its most basic form, started somewhere else and then arrived on Earth once things were already going. Of greater importance for us is the idea that if it could travel to Earth there’s a good chance it could travel anywhere (and everywhere). In fairness, there is some chance life started on say, Mars and travelled here, in which case maybe life isn’t “everywhere”. But if panspermia happened and it didn’t come from somewhere nearby, then that changes a lot.

Given the tenacity of life I’ve already mentioned above (see extremophiles) once it gets started, there’s good reason to believe that it would just keep going. This section is more speculative than the last section, but I don’t think we can rule out the idea, and it’s something Drake’s equation completely overlooks, and by extension, the SDO paper. That said, I’ll lay out some of the recent evidence and you can decide where it should fit in:

  1. Certain things double every so many years. The most famous example of this phenomenon is Moore’s Law, which says that the number of transistors on an integrated circuit doubles every two years. A while back some scientists wanted to see if biological complexity followed the same pattern. It did, doubling every 376 million years. With forms of life at the various epochs fitting neatly onto the graph. The really surprising thing was that if you extrapolate back to zero biological complexity you end up at a point ten billion years ago. Well before the Earth was even around (or Mars for that matter). Leaving Panspermia as the only option. Now the authors confess this is more of a “thought exercise” than hard science, but that puts it in a very similar category to Drake’s equation. And there’s an argument to be made that the data for the doubling argument is better.
  2. There’s a significant amount of material travelling between planets and even between star systems. I mentioned this in a previous post, but to remind you. Some scientists decided to run the numbers, on the impact 65 million ago that wiped out the dinosaurs. And they discovered that a significant amount of the material ejected would have ended elsewhere in the Solar System and even elsewhere in the galaxy. Their simulation showed that around 100 million rocks would have made it to Europa (a promising candidate for life) and that around a 1000 rocks would have made it to a potentially habitable planet in a nearby star system (Gliese 581). Now none of this is to say that any life would have survived on those rocks, rather the point that jumps out to me is how much material is being exchanged across those distances.
  3. Finally, and I put this last because it might seem striking only to me. Apparently the very first animal (as in the biological kingdom Animalia) had 55% of the DNA that humans have. They ascribe this to an “evolutionary burst of new genes”, but for me that looks an awful lot like support of the first point in this list. The idea that life has been churning along for a lot longer than we think, if the first animal had 55% of our DNA already half a billion years ago.

Now, of course, even if panspermia is happening, that doesn’t necessarily make the SDO paper wrong. You could have a situation where the filter is not life getting started in the first place, the filter is between any life and intelligent life. It could be that some kind of basic life is very common, but intelligence never evolves. Though before I move on to the next subject, in my opinion that doesn’t seem likely. You can imagine that if life itself has a hard time getting started, in any form, that out of the handful of planets with life, that only one develops intelligence. But if panspermia is happening, and you basically have life on every planet in the habitable zone, a number estimated at between 10 and 40 billion, then the idea that out of those billions of instances of life that somehow intelligence only arose this one time seems a lot less believable. (And yes I know about things like the difficulty of the prokaryote-eukaryote transition.)


The final reason I have for being skeptical of the conclusion of the SDO paper is that as far as I can tell they give zero weight to the fact that we do have one example of a planet with intelligent life, and capable of interstellar communication: Earth. In fact if I’m reading things correctly they appear to give a pretty low probability that even we should exist. My sense is that when it comes to Fermi’s paradox this is the one piece of evidence no one knows exactly how to handle. On the one hand, as I pointed out, the history of science has been inextricably linked to the Copernican principle. The idea that Earth and humanity are not unique, and yet on this one point the SDO paper make the claim that we are entirely unique, that there is probably not another example of detectable life anywhere in our galaxy of 250 billion stars. 

You might think there is no, “On the other hand”, but there is. It’s called the anthropic principle, which says there’s nothing remarkable about our uniqueness, because only our uniqueness allows it to be remarked upon. Or in other words, conscious life will only be found in places where conditions allow it to exist, therefore when we look around and find that things are set up in just the right way for us to exist, it couldn’t be any other way because if they weren’t set up in just the right way no one would be around to do the looking. There’s a lot that could be said about the anthropic principle, and this post is already quite long. But there are three points I’d like to bring up:

  1. It is logically true, but logically true in the sense that a tautology is logically true. It basically amounts to saying I’m here because I’m here, or if things were different, they’d be different. Which is fine as far as it goes, but it discourages further exploration and a deeper understanding of why we’re here, or why things are different, rather than encouraging it.
  2. To be fair, it does get used, and by some pretty big names. Stephen Hawking included it in his book A Brief History of Time, but Hawkings and others generally use it as an answer to the question of why all the physical constants seemed fine tuned for life. To which people reply there could be an infinite number of universes, so we just happen to be in the one fine tuned for life. Okay fine, but there’s no evidence that the physical constants we experience don’t apply to the rest of the galaxy. The only way it makes sense for Fermi’s Paradox is to argue that our Solar System, or the Earth is fine-tuned for intelligent life. Or that we were just insanely, ridiculously lucky. 
  3. It’s an argument from lack of imagination. In other words, critics of the paradox assert that we are alone because there has not been any evidence to the contrary. But it is entirely possible that we have just not looked hard enough, that our investigation has not been thorough enough. On questioning they will of course admit this possibility, but it is not their preferred explanation. Their preferred explanation is that we’re alone and the filter is behind us, and they will provide a host of possibilities for what that filter might be, but we really know very little about any of them. 

As you might have gathered, I’m not a very big fan of the anthropic principle. I think it’s a cop out. Perhaps you don’t, perhaps, on top of that, you think the idea of panspermia is ridiculous. Fair enough, my project is not to convince you that the anthropic principle is fallacious, or that panspermia definitely happened. My project is merely to illustrate that it’s premature to say that the Great Filter is behind us, that the Fermi Paradox is “solved” or “kaput”. And all that requires is that any one of the foregoing pieces of evidence I’ve assembled ends up being persuasive. 

Beyond all this there is the question we must continually revisit, in which direction is the error worse? If the Great Filter is actually behind us but out of an abundance of caution we spend more effort than we would have otherwise on x-risks, that’s almost certainly a good thing. In particular since there are plenty of x-risks which could end our civilization which are nevertheless not the Great Filter. Accordingly, any additional effort is almost certainly a good thing. On the other hand, if the Great Filter is ahead of us, then the worst thing we could do is dismiss the possibility entirely, and dismissing it on the basis of a single study might be the saddest thing of all.

Much like with Fermi’s Paradox, everyone reading this assumes that if they’re intelligent enough to appreciate this post, then there must be other readers out there somewhere who share the same intelligent appreciation, but what if there’s not, what if you’re the only one? Given that this might be the case wouldn’t it be super important for you, as the only person with that degree of intelligence to donate

Fermi’s Paradox and the Dark Forest

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I thought that while I was in the zone I would continue the discussion of Fermi’s Paradox I started in my last episode. As a reminder, the paradox is, that, despite the seemingly high probability that aliens exist, we have seen no evidence of them. As I also mentioned in my last episode (and explained at great length in an episode I recorded late last year) my explanation of the paradox is that we ARE communicating with aliens we just call the communication prayer, and the aliens God.

In order for this to make sense I am assuming that given enough time that aliens would be indistinguishable from gods. From a technological perspective everyone seems to basically agree that this would be the case. But what about from the standpoint of morality? Would aliens with the technology of gods also have the benevolence of gods?

At least one explanation of the paradox argues that aliens aren’t naturally benevolent. That in fact the reason we see no evidence of aliens is that they’re all hiding, worried that by revealing their presence they will give away their location to a galaxy full of other aliens who are not only more powerful, but who, once alerted to their existence, will have every reason to destroy them.

The recent science fiction series Remembrance of Earth’s Past (also called the Three Body Trilogy) by Chinese author Liu Cixin is built around this explanation of the paradox, and once again if you’re worried about spoilers you might just want to skip this episode.

Still here? Very well then, he calls this explanation the Dark Forest, and he describes it thusly:

The universe is a dark forest. Every civilization is an armed hunter stalking through the trees like a ghost, gently pushing aside branches that block the path and trying to tread without sound. Even breathing is done with care. The hunter has to be careful, because everywhere in the forest are stealthy hunters like him. If he finds other life–another hunter, an angel or a demon, a delicate infant or a tottering old man, a fairy or a demigod–there’s only one thing he can do: open fire and eliminate them. In this forest, hell is other people. An eternal threat that any life that exposes its own existence will be swiftly wiped out. This is the picture of cosmic civilization. It’s the explanation for the Fermi Paradox.

Liu’s theory, and by extension his worry is not unique. There are many people who warn about the dangers of actively revealing our location and existence to the rest of the universe. Stephen Hawking has said that we should avoid revealing ourselves to aliens because contact between us would end up similar to contact between the Native Americans and the Europeans (with humanity playing the role of the Native Americans). David Brin, a noted science fiction author, has also been very vocal in urging caution. These people would have no need to issue warnings if there was not group of people, on the opposite side of the issue, who actively advocate broadcasting our existence as widely as possible. These broadcasts are called either METI (Messages to ExTraterrestrial Intelligences) or Active SETI (Search for ExTraterrestrial Intelligence). The two sides both have valid points, and it is not my intention to enter into a debate on the merits of METI. I’m more interested in discussing how benevolent advanced aliens are likely to be, though I can see where that discussion could have a definite bearing on the wisdom of METI.

As long as we’re in the realm of science fiction, there is another set of books which explores this issue. This series of books by Fred Saberhagen is about an intergalactic scourge of self-replicating robots called the Berserkers.  (Imagine the Terminator movies only on a galactic scale.) The Berserkers were created long ago in a war between two extraterrestrial races. Having passed beyond the control of their creators their mission is to destroy all life, and they feel no remorse or pity.  The books follow the desperate war for survival humanity is forced to wage against this most implacable foe. These fictional Berserkers are a fantastic example of exactly the sort of thing that Brin and Hawking are worried about. And if that’s the kind of aliens who are out there, then we should indeed do our best to remain hidden and it further goes without saying that METI is a colossally bad idea. But are the Berzerkers a good representation of the extraterrestrial civilizations we’re likely to meet? Or to restate it, what level of benevolence should we expect from an extraterrestrial civilization when and if we ever encounter one?

Let’s start by examining the hypothetical malevolent, aliens. The kind who wander the Dark Forest shooting infants and old men on sight. We can imagine that they would come in two types.

The first type are purposefully malevolent, e.g. the already mentioned Berserkers. While they could be similar to what was envisioned by Saberhagen, they could also take the form of an out of control AI, some sort of resource maximizer with no morality we can detect or a morality completely foreign to us. Despite our inability to understand them, they would have an expansive and all consuming purpose. Something that drives the extraterrestrial civilization to swallow up humanity if for no other reason than that they represent resources which can be put to better use.

Extraterrestrial civilizations in this category would not need to be truly malevolent, anymore than someone building a road is expressing malevolence towards the ant hill they pave over. The best example of this in fiction might be the opening of the Hitchhiker’s Guide to the Galaxy. The Vogons show up to destroy Earth because it’s in the way of a hyper-spatial bypass. There is more interaction between the humans and aliens than between us and an anthill, but not much more. Humanity is simply not important to them. When one considers the, almost certain, vast technological difference between humans and any aliens we might encounter, positing that the interaction might be similar to that between us and the ants is probably not far off.

Of this first type we can say a couple of things, to begin with they would spread fast. In the example of both the Berserkers and the resource maximizers their malevolence comes from their single-minded motivation. This single mindedness would drive them to accomplish their goals in the most expeditious fashion possible which means expanding at a truly blistering rate from the standpoint of interstellar travel. Of course as has been discussed here and elsewhere it doesn’t even take a blistering rate of expansion for the Milky Way to have long ago been completely colonized.

Thus we are once again brought to Fermi’s Paradox and the question that created it, “Where is everybody?” If there is an advanced, expansionistic, single-minded, malevolent civilization out there, why have they not already arrived? The arguments related to this are well-trod, both by myself and others, but to restate it as it relates to this particular argument. Let’s assume that if we can make it another 10,000 years that we won’t have to worry about the Berserkers because it will either be obvious that they don’t exist or we will be technologically advanced enough to not have to worry. That sounds like a long time, but for the kind of rapaciously malevolent civilization we’re talking about it wouldn’t matter if they got to Earth two billion years ago or tomorrow, the result is the same. If the Berserkers had shown up at any point since the start of life 3.8 billion years ago, we’re assuming that it would all be over. In other words we’re 99.9997% through the danger zone. I choose the figure of 10,000 years, but if it makes you feel better you could use 100,000 or a million years and all you’re doing is moving the decimal point one or two places. The point is that if this kind of extraterrestrial civilization exists they should have wiped out life on Earth long, long ago.

The second category of malevolent extraterrestrial civilizations resembles the Europeans I mentioned earlier. They’re not single-minded about anything. They have plenty to keep the occupied in their own corner of the galaxy, but if they become aware of us, or specifically aware that we have something valuable. Some number of them will arrive to take it from us, without much concern for the impact. If we do fight back they may decide to exterminate us, but only because it’s easier than the alternative. This category of extraterrestrial civilization presents an interesting thought experiment. If they’re just consuming the raw material of the universe in the most expeditious fashion available, then they fall into the first category of malevolent aliens.

For them to fall into the second category, and for them to be of concern to the opponents of METI, their expansion has to have basically stopped, but we have to possess something so valuable that they’re willing to come and get it, expending the enormous resources necessary to reach us. (You may argue that for sufficiently advanced aliens the journey might be trivial. If so why aren’t they here already?)

What could we have that is so valuable? The costs of “importing” raw materials over a distance of multiple light years is so ridiculous as to be unthinkable. Only something unique could possibly have any interest to the aliens. Are we imagining that we have the only supply of iron or rhodium in the galaxy? No, the only thing truly unique to Earth is Earth based life, meaning that if anything the aliens might end up taking better care of the planet that we do. One could certainly imagine that they might take some humans and put them in a zoo, in fact the Zoo Hypothesis (closely related to Star Trek’s Prime Directive) is one of the explanations for the paradox. But just like humans, the aliens would probably want to largely leave earth alone. In any event this scenario bears no resemblance to the Dark Forest as described by Liu.

One could imagine extraterrestrial civilizations between the two extremes, expansive, but taking millions of years to go from one solar system to the next. Even in this case the galaxy is so old we still have to wonder that we haven’t encountered them yet. And again we have to imagine aliens who are close enough that they will arrive in the window where we can’t defend ourselves, but far enough away that they haven’t arrived already.

As an aside, this all assumes that there is no faster than light travel. If faster than light travel is possible (we just haven’t figured it out) then the situation is drastically different. Even so, we’re still left with the original question of “Where is everybody?” and if aliens can travel at faster than the speed of light, they should be everywhere, including here.

Thus far we’ve approached the question by starting with the assumption that there are aliens who are both advanced and malevolent. Now we’re going to question that assumption by examining whether it’s really possible to be both advanced and malevolent.

We are accustomed to thinking of nature as being red in tooth and claw, a Darwinian struggle where only the strong survive. I have no problem granting that in most cases this is in fact the case. But I would argue that it can’t be the case for an extraterrestrial civilization. To begin with all extraterrestrial civilizations would have to start as single planet civilizations. If it starts out as warlike how is it going to get off that planet? Let’s imagine what our own situation would look like if we were more warlike.

Colonizing even Mars is going to be enormously expensive, and enormously fragile. It wouldn’t take much to hamper the efforts while they were taking place on Earth or to fatally damage the colony’s chances once they were established. We’ve already talked about the difficulties of creating a permanent settlement on Mars. Now imagine that Elon Musk is trying to do it while we’re at war with Russia. The difficulty, which is already off the charts, would increase an hundredfold. In other words unless the original one planet civilization has an extended period of peace and cooperation they’re never going to become a multi-planet, extraterrestrial civilization. Once they’d mastered cooperation would they abandon it the minute they spotted the first alien? Also in any encounter between two of these civilizations one would almost certainly be, technologically, thousands if not millions of years ahead of the other, leaving the weaker of the two no choice but to cooperate, and the stronger no incentive to abandon the cooperative spirit they already possess.

Of course if you read much science fiction you’re going to encounter alien races who didn’t learn to cooperate, they were born to cooperate. In other words they resemble social insects, like ants or bees, with one queen and a lot of workers. These aliens might cooperate very naturally with each other, but not at all with anyone else. Making them naturally malevolent to anything they encounter. Here at last, perhaps, we have found a model for our malevolent extraterrestrial civilizations.. Though most of the previous caveats still apply. Why have we not already encountered them? Or if they’re not expansionary, what do we have that would make them change their mind?

Also, in this specific scenario we’re imagining something that resembles a super intelligent ant colony. Obviously it is unforgivably myopic to draw conclusions based only on the evidence of life on Earth. But you’ll notice that none of the life forms which work in this fashion have anything close to what we would describe as intelligence. One can imagine (as Douglas Adams did) that Dolphins might be sentient, but it’s a lot more difficult to imagine how ants eventually evolve to be a space faring race. As I said, lots of science fiction authors have imagined extraterrestrial civilizations that operate on a model similar to ants and other social insects (Ender’s Game and Starship Troopers both come to mind) but in every case these aliens have been hand waved into being a space faring race. I haven’t seen any credible attempt to explain how they would have evolved into one.

Perhaps that point is overly pedantic, but consider this. Technological progress is fed by idea generation, idea generation is fed by creative individuals, generally operating in a competitive environment with other creative individuals. If the thinking for your entire society is done by a handful of “queens”, how many ideas will actually be generated? It appears quite likely to me that if such a civilization did exist they would be fatally hampered by the inability to creatively generate sustained technological progress. To look at it from another angle, if a society is mindlessly cooperative then wouldn’t they lack the mind necessary to develop technology in the first place?

Of course there are a group of people I’ve talked about previously who believe that progress and morality go hand in hand. From their perspective obviously any aliens we encounter would be benevolent. You will also recall that in both my episode on the Religion on Progress and during my episode on  Steven Pinker that I took issue with these people, and yet it may appear that I’m making a similar argument. That godlike technology results in godlike benevolence. There are, however at least two important differences. The most fundamental being the assertion that just because someone, somewhere will achieve godlike technology and benevolence that humanity will inevitably do it as well. Perhaps an even even bigger difference is their assertion that the current progressive ideology of the last few decades is what has put us on this inevitable path to future perfection.  All that said, to the extent that our views do overlap I’m happy to use their opinions as additional support for the idea that a certain level of civilization requires a certain level of morality. (Though even here they may be reversing cause and effect.)

Having come this far I’ve hopefully established that we can eliminate certain categories of aliens from consideration. If all conceivable extraterrestrial civilizations are benevolent, then we can dispense with any discussion of what non-benevolent aliens might do and how that impacts the paradox. And, finally, with any luck, we’re left with assumptions that more accurately reflect the true state of the universe.

This is important because the field is already crowded with assumptions. Most of them derived, not from the sort of deep examination we’ve engaged in, but rather from the most recent TV show or movie the person saw (a point I made in my last episode.) If you were to establish a composite picture of alien contact based on the average person’s vision of it. Call this the distilled conventional wisdom of what aliens are like. It would involve them arriving suddenly, without any warning, sometime in the next few years. In addition, while they would be recognizably alien, they wouldn’t look too weird and they would have technology that’s advanced, but not too advanced, the sort of thing that given a few days or at most a few weeks, humans could easily reverse engineer. According to this convention wisdom we may marvel at their strange appearance, or be baffled by their weird ideas, but interaction with aliens really comes down to their technology. How does it work? How can we defeat it, steal it or use it to cure cancer?

Everything about the conventional wisdom of alien contact is silly, the silliest part being that they would arrive in the next few years after not giving any evidence of their presence for the last ten million. The next silliest is our conception of their technology. First what makes us think that alien technology is even going to resemble our technology. Remember Clarke’s Third law: Any sufficiently advanced technology is indistinguishable from magic. Secondly what makes you think that their technology would even enter into it?

If aliens are malevolent then of course their technology matters because how else are we going to stop them? If they’re neither excessively malevolent or excessively benevolent then their technology matters because what else do they have to offer? But if, as we have concluded in this episode their benevolence probably exceeds our own, then their technology might be of secondary importance, assuming we even recognized it as technology and didn’t just view it as magical (or perhaps even more likely miraculous). And of course we haven’t even taken into account how the aliens would react to us. One assumes that they wouldn’t just give us super-advanced technology and then wash their hands of the whole situation. They might just leave us alone, but if they were going to interact with us, it seems obvious that they’d want to improve our morality first.

I’d like to expand on that point with an analogy. Imagine that we’re dealing with a group terrestrial people perhaps an uncontacted tribe. As a starting point imagine which presents the greater difficulty, supplying them all with cell phones or implanting a morality into them? And when I say implanting morality, I’m not just speaking of giving them a bible, I’m talking about imparting actual morality, such that this group, going forward, ceases from all murder, rape, theft and even extramarital affairs. I think the answer is obvious. Just giving someone some technology is easy. Teaching them correct behavior (and here you may define correct behavior as anything you like) is extremely difficult, particularly if you have any interest in their behavior conforming to those teachings.

It would be the same for any highly advanced aliens who might exist. Giving us technology is easy. Teaching us how to use it without causing untold damage, that’s the hard part. Thus if a benevolent extraterrestrial civilization does choose to contact us, they might be far more worried about our morals than our tech level.

In the end we’re left with aliens being most likely beings of godlike technology and godlike benevolence who are mostly concerned with making humans moral. Am I the only one who thinks that sounds like a religion?

If you’re looking for an easy way to demonstrate your own advanced level of benevolence consider donating to this blog. Of course you don’t have to, but it’s what all the cool aliens are doing.

Fermi’s Paradox and the Movie Interstellar

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After several political posts of varying intensity I thought it might be nice to take a break, and return to some of my other interests. In particular I wanted to return to a discussion of Fermi’s Paradox. If you haven’t read any of my previous posts on the topic you can find them here and here. I would recommend reading them first, but I also suspect you might not bother, so for those that don’t, allow me to provide a brief introduction, both to the paradox and to my specific take on it. In brief Fermi’s Paradox is the seemingly irreconcilable set of facts that on the one hand, we have not been visited or contacted by aliens despite, on the other hand, billions of planets on which life could arise and billions of years during which they could have visited Earth. As for my take on it I think the simplest resolution of the paradox is that we ARE communicating with aliens we just call the communication prayer, and the aliens God.  

I have a couple of methods available for advancing this very unorthodox opinion (an opinion largely shared by no one else.) First I can show ways in which the beliefs of traditional religions (Mormonism in particular) fit in with the facts and even the speculations associated with the paradox. Or second, I can show how none of the other explanations for the paradox make sense, or at least show they make less sense than my explanation. Of course on top of all of that I have to be able to communicate my ideas period. Which is a bigger challenge than it appears even aside from the obvious limitations of being me. One of the ways to overcome that challenge is to piggyback on something from popular culture. And that is what I intend to do in this post, by discussing Fermi’s Paradox using the movie Interstellar.

I only recently got around to watching Interstellar. (I know. I’m behind.) And even though it never mentions Fermi’s Paradox it ends up lurking in the background nonetheless. The movie itself was interesting and beautiful, and engaging. It also about gave me an aneurysm. If you haven’t seen the movie and you don’t want to be spoiled then you should probably skip this post. But we’re also talking about an Oscar-winning movie (ok, it was just visual effects) from two years ago that made $675 million dollars worldwide. If you haven’t already seen it by now, can you really expect to not be spoiled? I certainly had no such expectations.

The point of talking about Interstellar is not to get into a detailed review of the movie. I’m more interested in talking about how the movie portrayed things like space travel, aliens, habitable planets, and the future of humanity, and tying that portrayal into a discussion of the paradox.

Let’s start with space travel. If you read my post from a couple of weeks ago you know how costly it is to get out of gravity wells. And indeed in Interstellar they needed a two stage rocket to get off of Earth, so there is some acknowledgement of what’s called the tyranny of the rocket equation. But after this brief nod to reality for the rest of the movie escaping gravity wells is trivial. In particular they have no problem either lifting off from a planet with 1.2 times the gravity of Earth or casually maneuvering in the vicinity of a black hole using just their lander. I have seen some weaselly answers about how the lander used a different fuel, with some people suggesting anti-matter. Ahh… yes those troublesome anti-matter engines are always flooding. They just cannot handle the tiniest bit of water. (That said the visuals of the giant wave were very cool.)

Moving beyond the physics of Interstellar the movie also implied that space travel had to happen quickly or it wouldn’t happen at all. Not to spend the entire post picking on the movie (though that may be where we’re headed) but as far as I could tell Cooper finds NASA and then launches into space the next morning, or maybe the next week? The timeline was a little unclear, but in any event it sure looked like he only had about 15 minutes to say goodbye to his daughter.

In reality any potential travel of the kind we’re talking about when we talk about the paradox, that is aliens spreading out across the entire galaxy, would happen over millions if not billions of years. Presumably this is one of the reasons why Nolan introduced the food crisis. For the movie to be dramatic there had to be some urgent reason to get off of earth. This is not to say there might not be some catastrophe that would make departing Earth both important and urgent, just that if there was, we’re probably screwed. As are the humans in Interstellar in the absence of the wormhole. Getting off the planet and creating a sustainable extraterrestrial colony (to say nothing of an extrasolar colony) would be the result of a slow grind lasting decades of not centuries. In other words if all other potential alien species are trying to get off their planet in the midst of a crisis while being sabotaged by Matt Damon, then it may make sense that we haven’t run into any of them, but I assume that’s actually fairly rare, particularly the Matt Damon part.

The next subject I’m interested in is the way the movie portrays aliens. Of course the paradox would be solved if we ever did encounter intelligent aliens. And they do just that in Interstellar. Though, once again, the movie ends up imposing a lot of implausible restrictions. To begin with it’s strongly implied that they aren’t aliens. That they’re humans from the future who’ve forgotten how to communicate with us. This is very convenient from the standpoint of telling the story, but it doesn’t make a lot of sense otherwise. Apparently they can understand humanity, and Cooper in particular, well enough to make a four dimensional copy of the daughter’s room (or maybe it’s even more than four), but not understand us well enough to actually have a conversation?

As it turns out, the inability to communicate is one favorite and common explanation for the paradox. When presenting this explanation people often use the metaphor of humans trying to communicate with ants. And it’s true that we are not great at communicating with ants. For instance we don’t have long conversations with ants about free will or the nature of the universe, but we can still communicate with them and we do so far more effectively than the aliens in Interstellar can communicate with humans. We can get ants to go where we want, we can move ants, we can kill ants, we can separate ants into their different roles, etc. I know that some of that doesn’t sound like communication, but trust me, getting snatched and moved someplace else communicates volumes. At this point we’ve seen zero evidence of intelligent extraterrestrials, while I think it goes without saying that ants have seen plenty evidence of us. And if aliens just wanted to let us know they exist there are plenty of things they could do to communicate that. In fact it would be difficult for them to not communicate it.

Instead, for some vague reason, these future humans have lost the ability to communicate with us. Also they wait to contact us (and I use the term contact very loosely) until the Earth is uninhabitable and we’re about to die. How are they sure this is when they should intervene? Were they ever worried about us during the Cold War? Does this have anything to do with the weird time-travel paradoxes? Perhaps, but in any event they intervene using their near godlike powers and set up a wormhole near Saturn. And this wormhole leads to a couple of planets that are essentially uninhabitable, and a third planet where nothing grows, but at least it doesn’t have 4,000 foot tall waves. And all of this is in another galaxy.. near a black hole so big they call it Gargatua…

This takes us naturally to the subject of habitable planets. I know I said I wasn’t going to spend the entire post picking on the movie, but perhaps it’s unavoidable, because it’s “stance” on habitable planets was kind of ridiculous. So we’ve got these aliens, or future humans, or whatever, and they want to rescue humanity, so they create a wormhole. I’ve already mentioned that we have to go all the way to Saturn to get to this wormhole. But to be fair perhaps they’re limited on where they can create these wormholes, and they can’t get it any closer to Earth than the orbit of Saturn. If so they must be really limited on the other side because, as I already pointed out, the only planets they can get near to on the other end are objectively awful. I’ve already mentioned the water planet with gigantic waves but in addition to that the planet is so close to the giant black hole that one hour there equals 7 years of time everywhere else.

The second is completely covered in ice, and based on the fact that there is no surface it probably isn’t even as good a candidate for colonization as Mars or Europa, which the ship passed on it’s way to the wormhole. The final planet appears to be a vast desert, whose main advantage appears to be that at least it has a breathable atmosphere?

If planets that can support life are really as rare as Interstellar makes them out to be (you have to go to another galaxy to find even a sucky one) it would be a great explanation for the paradox. Unfortunately we already know they’re not. Just looking at the planets we’ve found using Kepler (which by the way has only examined a tiny fraction of the galaxy, around one-millionth, if that) we’ve already found 3,565 planets, 34 of which are potentially habitable. If you do the math you’re looking at 34 million potentially habitable planets, without having to go to another galaxy (also I’m pretty sure that none of the 34 potentially habitable planets Kepler has found are anywhere near a black hole.) In fact the nearest potentially habitable planet is just the next star over. Which makes the choice of the wormholes’ end point even more baffling. All of this is to say that if Interstellar is your primary source of information about how common habitable planets then you’re going to end up with a lot of very wrong ideas.

The last element I said I wanted to examine from Interstellar is it’s vision for the future of humanity. I already mentioned that the food crisis is one of those things that is manufactured to provide urgency, but this is not to say that we couldn’t have some gigantic agricultural collapse. That certainly could happen, but the big problem with the scenario is that if we can’t grow crops on the Earth, we are unlikely to be able to grow them anywhere else. As I point out in the blog I already mentioned, nearly everywhere on Earth from Antarctica to the depths of the ocean, is more hospitable to life, particularly that life which evolved on Earth, than any conceivable extraterrestrial location. In Interstellar they lose the ability to grow okra. Let’s just say that if you can’t grow okra in Georgia you’re not going to be able to grow it on a lifeless desert planet in another galaxy.

Another fascinating element of Nolan’s vision of the future was the way in which they decided to declare the moon landings to be a hoax. First that represents something of a nightmare for me, so it definitely got my attention, second it implied a sort of collectivist mindset. None of us are going to escape unless all of us can escape. This is something else I talked about in my previous post on space colonization. There are a lot of noble ideals which end up not being compatible with the core value of saving humanity, and creating the illusion that we couldn’t even get men to the moon in order to help people to focus on Earth is definitely one of those ideals.

But of course the most consequential element of Nolan’s vision for the future of humanity was that we would someday transcend time, come back and save our past selves. This by itself is not that interesting. Nolan is not the first to imagine some sort of technological transcendence. Where it does get interesting is in how it relates to one of the leading explanations of the paradox. As I mentioned in one of my previous posts on the subject, many people favor the explanation that we are in fact alone. That despite billions of planets and billions of years that we are the only intelligent species in existence. By making the aliens future humans, Nolan comes to essentially the same conclusion. And it’s a conclusion with some terrifying implications. This is not the space to go into a full examination of all of them, but at a minimum it implies that there’s no one out there to save us. If, on the other hand, there are aliens you can always imagine that they my someday show up with the cure for cancer, unlimited free energy and super delicious donuts. You can also imagine something similar if God exists. But if neither exists then we have to save ourselves. And while some people may find that empowering (if they think about it at all). When I look around and see how flawed humanity is, I think if we’re all there is, then more likely than not we’re in a lot of trouble.

You may think that this is an awful lot of time to waste examining the ideas of a movie whose only goal was to entertain. Particularly since I agree that it was entertaining. But I read something recently (unfortunately I can’t locate it now) which made the excellent point that fiction, specifically movies and TV, are more and more taking the place of history as a guide for what might happen, or what should be avoided, or whether something is a good idea. To put it more bluntly we are being educated by entertaining lies rather than by reality. As I recall, the article used the example of a discussion about artificial intelligence. In any discussion of artificial intelligence you would not be surprised if someone referenced a Skynet scenario, drawing on the Terminator movies and the idea that a given artificial intelligence (in the movie it was Skynet) could come alive and immediately try to destroy humanity. Another example would be if someone (including myself) wants to talk about a post apocalyptic scenario they might reference Mad Max. This is in contrast to the past when people might talk about something being similar to Caesar’s rivalry with Pompey or they might draw inspiration from the Battle of Marathon (enough so that they created a race in it’s memory.)

In the past people were frankly inundated by history. A large part of schooling was learning Greek and Latin. This wasn’t so they could talk to people in Latin (or Greek) it was so they could read history in its original language. If you thought of history as their popular entertainment you would not be far off. But of course now, while history isn’t missing from our popular entertainment (The TV series Rome is a good example of this) it’s a pretty small slice. Entertainment these days is largely dominated by fiction (All superhero movies, Star Wars, anything animated) and present day navel gazing (essentially everything currently on TV). Using what has happened as a guide to what might happen, is no longer done. Instead we are educated (and I use that term loosely) by the fictitious imaginings of a few creative individuals with unclear (if not actively harmful) motivations.

There are two reasons for this change. First, there are certain situations, like a malevolent AI, or nuclear apocalypse which have no historical analogies. If you wanted to talk about some point of no return for AI, you could draw on history and use, say, Caesar crossing the Rubicon. But the Skynet example, despite being fiction, is a better description of what might actually happen. This first reason is generally harmless and possibly even useful. But there is another reason for people to draw on fiction rather than history, it’s more accessible and easier to understand. Unfortunately that doesn’t make it more accurate. In fact fiction is, almost by definition, less accurate. So in situations where there is something in history to guide us we should always draw upon that first.

What does this have to do with Fermi’s Paradox? Surely this is one of those things that has no historical analog and movies, even horribly misguided movies like Interstellar are going to be the best analogies we have. I know it seems that way, but with the paradox, that’s not the case. We have a wealth of history to draw on, in fact we have all of history.

While it is true that there are some who will argue that we have already been visited by aliens. (My own theories on alien divinity aside.) There is no evidence for an alien visitation as it is typically imagined. This is particularly true if you look at ALL of history, not just recorded history. Allow me to explain. There are various theories that Stonehenge or the Great Pyramid or the Nazca Lines were all built by aliens. But all of these are recent enough that humans could have built them. If we’re talking about aliens they could have left artifacts on Earth at any point in its 4.5 billions years of existence, now sure some of these might have been sucked into the mantel and destroyed, (or to avoid that they also could have placed them on the moon similar to 2001) but even accounting for that there were still millions of years for the aliens to leave some evidence of their presence. But they didn’t.

This is what I mean by using history not just popular culture when judging the likelihood of something. If you just pay attention to popular culture you probably think that aliens could show up any day now. That despite millions if not billions of years of not showing up, that it could happen next week. We see this conceit with Interstellar, and also with the more recent movie, Arrival. In fact I would I would be curious to see how people would respond if they were polled on the probability of aliens showing up. My guess is based on the enormous number of movies and TV shows depicting just that, that the probability would end up being quite high. Despite no evidence for it happening anytime in the last million years.

This is the danger of using fiction to understand the world. Any serious study of Fermi’s Paradox reveals that it’s one of the most important questions facing humanity. And if I’ve managed to convince you that the existence of God is tied up with it, then it only becomes more important. And yet people assess the probability of encountering or communicating with aliens based on a recent movie rather than on a sober assessment of reality.

The challenges humanity face are not trivial. The cannot be solved with an entertaining two (or in Interstellar’s case, three) hour movie. I think everyone should be hoping that God exists, because if not we most likely are on are own. And however much Anne Hathaway urges us to trust in love, if we are all alone in the universe I think it’s going to take a lot more than that to save us.

If you think I’m completely wrong about things then you should donate to this blog while you still can, because once the aliens do show up money will have no meaning.

The Secular Answer To Fermi’s Paradox

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Having explored at some length in our last post the idea that Fermi’s Paradox may offer strong support for the existence of God.  As well as the idea that assumptions made about extraterrestrial communication line up better than might be expected with the process of prayer. I want to flip the coin and look at what the conventional wisdom is as far as the Paradox. For my examination I will be mostly drawing from If the Universe Is Teeming with Aliens … WHERE IS EVERYBODY?: Fifty Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life, by Stephen Webb. There has obviously been quite a bit written about the paradox, but this appears to be one of the only (if not the only) book length treatments. My discussion will use the first edition of the book, which has 50 potential explanations for the Paradox. The second edition, which I have yet to acquire has 75 potential explanations. I cannot speak definitively about the second edition, but of the 50 potential explanations in the first none resemble the explanation I offered in my last post. But otherwise it is admirably comprehensive.

Webb breaks extraterrestrials into three broad categories:

  1. They are here.
  2. They exist but have not communicated with us.
  3. They don’t exist.

The first possibility is broader than the initial title would suggest. It essentially encompasses all scenarios under which aliens exist, and are aware of us. These explanations range from the humorous (They are here and they call themselves Hungarians) to explanations for why, if they exist, they might choose to hide from us. The classic example of this thinking is the Prime Directive from Star Trek, the principle that the federation will not interfere with any less advanced civilizations.

Interestingly enough the final explanation in the “They are Here” section is titled “God Exists”. From the title, at least, it sounded like it must be very similar to my own thinking. It wasn’t. Webb spends a couple of paragraphs talking about some vague theological issues, but then spends the rest of the section (four more pages) examining the idea that there seems to be no good reason for the constants of the Universe to have the values they do (for example the strength of the weak nuclear force or the mass of an electron.) From there he goes on to discuss a theory of universe evolution under which new universes might be created by black holes so universes would “evolve” to maximize black hole production. If the physical constants which lead to the creation of black holes are similar to the constants necessary for the emergence of life you might end up with the second condition being a byproduct of the first.

The second possibility, that they exist but have not communicated with us, generally boils down to the idea that on top of the enormous number of stars and the enormous amount of time that has passed, which argue in favor of alien life, that there are other enormous numbers: the distance between habitable planets (less now than a couple of weeks ago); the number of ways language and communication could develop; the different types of intelligent life; and so forth, which argue against alien communication. This could mean that it’s just too far, or that they are communicating with us and we don’t understand, or in one of the more off-beat explanations, perhaps most worlds have skies perpetually shrouded in clouds. In which case, would they ever even develop astronomy, or even a full Newtonian understanding of the Universe?  

The final possibility is that there is some kind of filter which works against intelligent extraterrestrial life. Some process which keeps life from starting at all, from reaching sufficient complexity, from developing consciousness, from lasting long enough to spread, or from accomplishing any of the thousands of steps required to have a truly interstellar civilization. As you can imagine, such a filter might be behind us, or it might be in front of us. Examples which have been offered for filters we have already passed, have included: the difficulty of moving from prokaryotes to eukaryotes, galactic catastrophes like supernovas, getting life started in the first place, and even plate tectonics.  

Examples which have been offered for filters yet to come include: blowing ourselves up with nukes, losing ourselves in virtual reality, civilizational collapse, or of course galactic or solar catastrophes yet to come. Another explanation is that aliens do exist, but they’re aggressive and warlike and no one wants to risk initiating communication (or what’s termed Active SETI) because they’re all afraid they’ll be discovered and destroyed.

This is of course one of the things that makes Fermi’s Paradox so fascinating, the number of possible explanations is huge and those explanations can tie into anything (from the Runaway Consumerism to having a particularly large Moon.)

I said that Webb’s book offered up 50 explanations for the paradox. That’s not entirely true. He actually offers up 49 explanations and then for the 50th he offers his own explanation. He mentions in one of the introductory sections that the 50th explanation will be his explanation for the paradox, and while reading the book I was intensely curious about what his explanation would be. And if, for whatever reason you were thinking of reading the book (which I recommend only if you are REALLY interested in the paradox) and you don’t want to be spoiled you should stop reading now…

Webb’s final solution titled “The Fermi Paradox Resolved…” is not unique, it’s not some new take on things or an explanation that hasn’t been offered already, it’s the combination several explanations. Having gone through 49 possible explanations for the paradox Webb’s answer is that we are alone. This is an interesting conclusion. And I think he reaches it somewhat reluctantly, but it carries an enormous number of consequences, not all of which he’s willing to grapple with. But before we get to that let’s examine how he arrives at his conclusion.

In a similar fashion to how Fermi and Drake arrived at their numbers, Webb comes up with is own filter for determining how many intelligent civilizations there should be. All of his filters come from the previous 49 explanations of the paradox already laid out in his book. And in a fashion similar to Drake, he starts with the number of stars in the galaxy. He then multiplies that by the average number of planets per star. This gives him a number of 10^12 or one trillion potential planets. Starting from there he begins to filter planets out. His filtering process is somewhat involved and scholarly, but it’s interesting enough that I’d like to walk through it. He goes through seven steps (actually 8, but one of his steps doesn’t actually filter anything, so we’ll skip it.)

Step 1- Eliminate any planets not in the galactic habitable zone. Most people are familiar with the solar habitable zone, (discussed more in step 3). This is the same thing on the galactic scale, and mostly has to do with the frequency of large scale galactic catastrophes. If you’re too close to the center of the galaxy, then the density of stars is such that galactic catastrophes would be frequent, potentially too frequent for life to ever establish a foothold. Consequently only stars out on the rim of the galaxy would accident free enough for life to develop, and this region is the galactic habitable zone. Webb uses an estimate of 20% of stars being in this zone so that takes us down to 200 billion planets.

Step 2- Eliminate any planets which don’t orbit sun-like stars. Bigger stars burn too fast and smaller stars don’t give off enough energy. Only 5% of stars are sun-like (G-Type) which leaves us with 10 billion planets.

Step 3- Eliminate any planets which aren’t in the continuously habitable zone (CHZ) of the star. This means, not only do they currently have to be at a distance from the star where water is liquid, but they have to have always been at that distance. He puts this number at 0.1% of planets. Which frankly seems extremely conservative particularly in light of the data we’re getting from Kepler which is biased against Earth-sized planets. To be fair to Webb part of the low estimate comes from the idea that the Sun was much fainter in the past. That filter takes us to 10 million planets.

Step 4- Eliminate any planet in the CHZ on which life doesn’t actually emerge. After saying that he considers life to be a probable occurrence for planets in the CHZ he, somewhat unexpectedly, goes on to say that it would happen on only 5% of them. Which takes us to half a million.

Step 5- Eliminate any planet where life gets wiped out by a supernova or some similar solar or galactic catastrophe. Here he’s fairly optimistic and thinks that only about 20% of life would be eliminated in this fashion. I think on this step, contrary to all the other steps he is too optimistic, that possibly far more than 20% could be wiped out by something like a supernova or some giant collision. Though we have also eliminated the planets most prone to this in Step 1. In any event this takes him to 400,000.

Step 6- Eliminate any planet where life doesn’t ever get to be multicellular. Conveniently he places the odds at life making the jump from single celled to multi celled at 1 in 40 which works out nicely to give us 10,000 planets with multicellular life.

Step 7- Eliminate any planets where life doesn’t produce an intelligent, tool-using, mathematical species capable of developing technology. He thinks the odds of this happening are least 1 in 10,000 (0.01%) and possibly much greater which means that there is only one of those civilizations, us. We are alone.

At first glance the whole process seems scientific, but similar to the Drake equation Webb has very little evidence for any of his estimates. The late Michael Crichton of Jurassic Park and Andromeda Strain fame once gave a talk about the Drake Equation at Caltech. His purpose was to take a shot at global warming, and perhaps you’ll dismiss it on that grounds, but his point was nevertheless valid:

This serious-looking equation gave SETI a serious footing as a legitimate intellectual inquiry. The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. And guesses-just so we’re clear-are merely expressions of prejudice.

Nor can there be “informed guesses.” If you need to state how many planets with life choose to communicate, there is simply no way to make an informed guess. It’s simply prejudice.

As a result, the Drake equation can have any value from “billions and billions” to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless, and has nothing to do with science. I take the hard view that science involves the creation of testable hypotheses. The Drake equation cannot be tested and therefore SETI is not science. SETI is unquestionably a religion.

His point about SETI being a religion is particularly telling for the purposes of this blog and our discussion. As is his point that the guesses are an expression of prejudice. In the case above it’s obvious that Webb already has a final answer in mind before he started plugging in his guesses, it didn’t just happen to come out with one to his amazement and surprise, he arranged his guesses so that it would come out as one.

Think about that for a second, you start off with one trillion, and in the end you’ve created a filter that leaves just one planet left out of the one trillion you started with?  Not zero, not a million? Imagine that you were going to create a set of seven filters which when applied to 7+ billion humans left you with one and only one person, and that you could only use natural criteria, like weight and height, not artificial filters like a social security number or the name of the town they were born in. It would be impossible, and recall that Webb starts with one trillion planets, not seven billion, so he’s already dealing with potential set over 100 times as large.

But let us for the moment assume that he’s correct. That in all the galaxy we are the only intelligent, technological life. As I already mentioned, the consequences of that are far-reaching and extreme.

First it reverses one of the major trends in science. The trend towards de-emphasizing humanity’s place in the universe.

In the beginning if you were the ruler of a vast empire you must have thought that you were the center of creation. Alexander the Great is said to have conquered the known world. I’m sure Julius Caesar couldn’t have imagined an empire greater than Rome, but I think Emperor Yuan of Han would have disagreed.

But surely, had they know each other, they could agreed that between the two of them they more or less ruled the whole world? I’m sure the people of Americas, who were entirely unknown to them, would have argued with that. But surely all of them could agree that the planet on which they all lived was at the center of the universe. But then Copernicus comes along, and says, “Not so fast.” (And yes I know about Aristarchus of Samos.)

“Okay, we get it. The Earth revolves around the Sun, not the other way around. But at least we can take comfort in the fact that man is clearly different and better than the animals.”

“About that…” says Darwin.

“Well at least our galaxy is unique…”

“I hate to keep bursting your bubble, but that’s not the case either,” chimes in Edwin Hubble.

At every step in the process when someone has thought that humanity was special in anyway someone comes along and shows that they’re not. It happened often enough that now they have a name for it, The Copernican Principle (after one of the biggest bubble poppers). Which, for our purposes, is interchangeable with the Mediocrity Principle. Together they say that there is nothing special about our place in the cosmos, or us, or the development of life. Stephen Hawking put it as follows:

The human race is just a chemical scum on a moderate-sized planet, orbiting around a very average star in the outer suburb of one among a hundred billion galaxies.

This is what scientist have believed, but if we are truly the only intelligent, technology using life form in the galaxy, then suddenly we are very special indeed. Which, as you’ll recall, is what religion has been arguing all along, and it is primarily against religion that these various attacks at uniqueness have been leveled.

Now obviously it’s not impossible for the Copernican principle to be wrong, but you can still imagine that it presents a problem for scientists to explain. Particularly for scientists who would rather not give any ammunition to the unbelievers. In other words, for militant atheists, the idea that we might be unique and special, that the universe and the galaxy and the solar system might have been designed for us, is deeply troubling. And if you talk to any of them who are knowledgeable about this issue, they have a response ready, the Anthropic Principle.

The Anthropic Principle is complicated enough that it almost certainly deserves it’s own post, particularly as we are already 2500+ words into this post, but in short what it says is that there’s nothing remarkable about our uniqueness, because only our uniqueness allows it to be remarked upon.

To expand on that a little bit. Conscious life will only be found in places where conditions allow it to exist, therefore when we look around and find that things are set up in just the right way for us to exist, it couldn’t be any other way because if they weren’t set up in just the right way no one would be around to do the looking.

As I said the subject is deep enough that it will probably eventually get it’s own post (though not next week I’m feeling a hankering for something different.) But I will end with four points about the anthropic principle to chew on:

1- It’s logically true, but logically true in the sense that a tautology is logically true. It basically amounts to saying I’m here because I’m here, or if things were different, they’d be different. Which is fine as far as it goes, but it discourages further exploration and a deeper understanding rather than encouraging it.

2- It’s generally used as an answer to the question of why all the physical constants seemed fine tuned for life. To which people reply there could be an infinite number of universes, so we just happen to be in the one fine tuned for life. Okay fine, but is there any evidence that the physical constants we experience don’t apply to the rest of the galaxy? Because that’s what we’re talking about when we talk about Fermi’s Paradox. In fact we don’t even have any evidence that they are different anywhere in the visible universe of the 100 billion additional galaxies. In other words if the Earth is fine-tuned for life as far as physical constants, so is the rest of the galaxy, at a minimum.

3- It’s an argument from lack of imagination. Or in other words Webb asserts that we are alone because there has not been any evidence to the contrary. It is entirely possible that we have just not looked hard enough. Webb admits this possibility of course, but it is not his preferred explanation, which is that we’re alone, because of the factors which I mentioned above, but all of those factors could just be a lack of imagination. Imagining how life could develop in the center of the galaxy, how life could develop outside of the CHZ (say Europa) or, especially, imagining how we might already be in contact with extraterrestrials and just call it prayer.

4- It’s not science. Just as Crichton (and others) argue that SETI is a religion, so is the anthropic principle. In this particular religion it’s easier to believe that we’re alone and use the anthropic principle as justification then to think that we’re not alone and that God exists. It’s the religion of, humanism, especially the belief that there is nothing beyond the limits of rationality and science.

When I said the consequences are far-reaching and extreme, this is what I meant. If we are truly alone, if we are the lone intelligence in the entire observable universe then that puts us in a position of awful responsibility, and takes us back to the premise of the blog. My assertion is that the harvest is past, the summer is ended, and we are not saved. If you assert that humanity is alone, that we are all there is, then what you’re saying is:

The harvest is past, the summer is ended, and we HAVE to be saved.

Fermi’s Paradox As a Proof of the Existence of God

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It all began one day sometime in 1950 at the Los Alamos National Laboratory. Enrico Fermi and some other scientists were discussing UFOs over lunch. It was the dawn of the atomic age (as they all well knew, working at Los Alamos) and anything seemed possible. Consequently their conversation covered all manner of speculative topics, including the potential for FTL travel. In the midst of their discussion, and seemingly out of nowhere, Fermi exclaimed, “Where are they?” The conversation had been so wide ranging, that it took the other scientists a moment to understand that he was talking about extraterrestrials. But in that moment the paradox which bears his name was born.

It was immediately apparent that Fermi’s question had touched on something deep. As the story goes Fermi went back to his office and ran some numbers (these calculations apparently pre-date the Drake Equation) and confirmed what he had already suspected, that even using incredibly modest assumptions, we should have been visited by extraterrestrials long ago and many times over. Instinctively Fermi and the other scientists recognized that the question touched on a deep paradox, which is why this question, out of all the questions ever asked while eating lunch, have survived to the present day.

I mentioned the Drake Equation, and it’s closely tied to Fermi’s Paradox, and it might be worth taking a brief detour into the question of what the Drake Equation is. One day in 1961 Frank Drake was preparing for a meeting on the search for extraterrestrial intelligence, and, according to his recollection, the equation came about during that preparation:

As I planned the meeting, I realized a few day[s] ahead of time we needed an agenda. And so I wrote down all the things you needed to know to predict how hard it’s going to be to detect extraterrestrial life. And looking at them it became pretty evident that if you multiplied all these together, you got a number, N, which is the number of detectable civilizations in our galaxy.

Drake’s equation essentially acts as a series of filters. (The concept of a filter will be very important in discussing Fermi’s Paradox.) You begin with the number of stars (technically the rate of star formation.) You then filter out any stars without planets. From there you filter out any planets which don’t have life, and then filter out that life which isn’t intelligent, and finally you filter out any life which is incapable of communicating on an interstellar scale. After filtering out all the possible stars and planets and life forms that aren’t communicating with us, you arrive at a number of, as Drake said, “detectable civilizations in our galaxy.”

What Fermi’s numbers and later Drake’s showed was that the first number, the number of stars, is so massive, (100 billion in the Milky Way) that even if you’re pretty conservative with your filtering you still end up with a big number. And even if you are very pessimistic with your estimates, and the number of expected civilizations ends up being small, another large number, the age of the galaxy, means that even if there only ended up being one star-faring civilization, they would have had plenty of time to spread out across the entire galaxy under almost any conceivable scenario.

The Drake Equation article on Wikipedia is fascinating, as is the article on Fermi’s Paradox, and I have borrowed heavily from both. In fact, rather than trying to restate everything I would just suggest that you read those articles. What I’m more interested in is viewing Fermi’s paradox through the lens of LDS Doctrine and LDS Cosmology. In the process, I don’t guarantee that we won’t end up fairly far afield, though I don’t imagine we will arrive anywhere too controversial.

LDS beliefs aside, from a broadly religious perspective it can only be viewed as fortunate that we haven’t been visited by extraterrestrials, or at least extraterrestrials of the sort envisioned by most science fiction. I don’t have the required background to speculate on the impact of such a visit on the eastern religions, but it could only be a huge blow to all the Abrahamic religions if aliens shows up and their belief system didn’t incorporate the idea of a single omniscient deity. It would therefore follow that Fermi’s Paradox works in favor of religion. In fact I would go so far as to say that Fermi’s Paradox is in fact a strong argument in favor of God generally, but, I hope to show that it’s even a stronger argument in favor of the specifically LDS conception of God.

The LDS conception of God is, as far as I know, unique among the religions. We’re basically in a category by ourselves when it comes the way extraterrestrials fit into our conception of God. To take just one example, directly from the scriptures:

And thus there shall be the reckoning of the time of one planet above another, until thou come nigh unto Kolob, which Kolob is after the reckoning of the Lord’s time; which Kolob is set nigh unto the throne of God, to govern all those planets which belong to the same order as that upon which thou standest.

Abraham 3:9

Obviously one can get pretty deep in the weeds when you start talking about Kolob and the more esoteric aspects of LDS cosmology, so I’ll try to keep that sort of speculation to a minimum. Even so, I don’t think one has to engage in much speculation to say that Mormons believe that God is an extraterrestrial, using the broadest definition of that term. Which, then means, if we follow that thought to it’s logical conclusion, that Mormons have the answer to Fermi’s Paradox. Fermi’s numbers suggested to him that we should have been visited by extraterrestrials long ago and many times. Well if God is an extraterrestrial then we have. There is no paradox. Additionally this would explain why no other extraterrestrials from visiting us (if there are other extraterrestrials in any meaningful sense in this scenario.)

On it’s face this argument seems perfectly reasonable to me, but I guess for most people it seems crazy, or impossible, or somehow unthinkable, because in all the time I’ve been interested in the paradox I don’t believe I’ve ever seen someone make this argument. (Though if past experience is anything to go by five minutes after I post this I’ll find someone making this exact argument.) I’ve have seen people come close. Interestingly one of the people who came the closest is Michael Shermer, a noted religious skeptic (he’s the founder of the Skeptics Society and Editor in Chief of Skeptic Magazine) In his answer to one of the Edge Questions of the Year he up the following:

Is God nothing more than a sufficiently advanced extra-terrestrial intelligence?

As you can see he get’s really close, but he never draws the connection between this question and the paradox, or makes the leap that I’m going to make which is to say that Fermi’s Paradox could be considered proof of God’s existence. I use proof in the sense of something which helps to establish the truth, not something which is ironclad and irrefutable. This proof would go something like this:

  1. Because of the huge number of stars and planets, it is inconceivable that we are the only intelligent life.
  2. Because of the huge amounts of time involved it is inconceivable that other intelligent life hasn’t spread through the galaxy and visited Earth.
  3. Because of the inevitable gigantic technological disparity which would exist between us and any spacefaring extraterrestrials they would appear to us as gods.
  4. Therefore the simplest explanation is that the being we refer to as God exists and fulfills all of the above criteria.

I feel like we should give this proof a name. Fermi’s Paradox’s indirect Proof for the Existence of God, seems too long, maybe Proof by Extraterrestrial Exclusion? In any event if someone out there thinks they see any big holes in this line of reasoning I’d welcome the chance to hear them. But I would argue that not only are there no holes in this line of thinking, but that most of the explanations which are offered for the paradox provide indirect support for this explanation.

I just got done watching The Big Short, which covers the housing crisis and the few people who were betting it would happen, and one of the main worries of the people in the movie was that they were overlooking something. That they had missed some key piece of information. If no one else was betting against the housing market maybe everyone knew something that they didn’t. They weren’t missing anything, but they were right to be skeptical, and at this point I should engage in similar skepticism. If no one has come up with this same line of thinking, am I missing something?

To continue with the comparison to the Big Short, a large part of the blindness which afflicted the people who were involved in the housing crisis was the assumption that you would never have a simultaneous nationwide decline in housing prices, in large part because it hadn’t ever happened before. I think a similar blindness affects the people thinking about Fermi’s Paradox. When people imagine aliens they mostly imagine a sort of ray-gun-flying-saucer sort of thing. Or they imagine something so inhuman that we might not even recognize it as life. Imagining that our contact with aliens might take the form of prayer is both too mundane and too fantastic. But to offer up an adaptation to Clarke’s Third Law (and I am not the first to suggest this modification):

Any sufficiently advanced technology is indistinguishable from a miracle.

Of course as all “educated” people know there aren’t any miracles, consequently when people involved in SETI look for signs of alien life they look for signals in the electromagnetic spectrum. Radio waves, or possibly lasers. And when they think of aliens visiting they think of something similar to Independence Day. But what should we be expecting if we really approach things without preconception or bias? (And by no means am I claiming that I am free from bias, only that I have a completely different set of biases.)

The first thing we should expect if we give any credence to Fermi is that they should already be here. This is obviously not what most people think. In fact most people have a bias towards expecting them to show up in the near future. A bias which got it’s start at the dawn of the age of science fiction with HG Wells and War of the Worlds (and almost certainly earlier than that, but Wells is probably the first author most people are aware of.) A bias which continues through to the present day with movies like the aforementioned Independence Day and the soon to be released Arrival.

But of course the chances that, in the 4.543 billion years of the Earth’s existence that aliens will pick next 50 to arrive are 0.00000001%. Aliens have either already visited or they never will. Communication would appear to be different than visiting, but not really. Think about it, if incredibly advanced aliens are out there then either they want to talk to us or they don’t. If they do want to talk to us then we should assume that, given that they’re thousands if not millions of years ahead of us in technology that they should have figured out a way to do it. Accordingly even if we restrict it to communication, I would once again say that there’s a strong bias towards it already happening, or never happening. Of course I’ve completely breezed past the idea that they’re waiting for something to happen before they talk to us. But that is an interesting enough topic that it deserves it’s own post. The point is, outside of some fringe theories about pyramids and Mayans the only current candidate for extraterrestrial communication is prayer.

I understand this will strike many people as an entirely ludicrous idea. But why? On what basis do they rule out this idea? I understand I may be accused of constructing a strawman, but since I haven’t seen this theory in print, let alone any objections to it, I don’t have any actual objections to answer, so we’ll have to imagine some. Still I think these won’t be too far from the mark.

Objection 1: Prayer is scientifically impossible.

Honestly I hope they’re smarter than this, and that this isn’t one of the objections, but I could certainly imagine that it would be. Everyone agrees that any potential aliens (LDS doctrine or no) would be at least thousands if not millions of years ahead of us technologically. How do we know, at our level of development what is or isn’t possible? I could trot out a list of everything we thought was impossible scant decades before it became commonplace. How can anyone have any confidence about predicting what is and isn’t possible with thousands, if not millions of years of additional progress?

Objection 2: Prayer is not the way aliens would contact us.

For people raised on the biases I already mentioned, when they imagine alien contact they imagine a single flying saucer landing in Washington DC or a scientist working late at night at some radio observatory. What they do not imagine is communication with single individuals that appears unreliable at best, mostly involves people asking for, or expressing gratitude for mundane things and is responded to with vague feelings of peace and the occasional (unconfirmable) vocalization. But why couldn’t it be? Once again it’s dangerous to make any assumptions about what extraterrestrials can and can’t do or would or wouldn’t do. To return to the Big Short, it opens with a quote by Mark Twain:

It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.

In future posts I’ll get more into why prayer may be precisely the way that an advanced race of beings may want to talk to us, even if it were unmoored from its religious origins.

Objection 3: Prayer is inexplicably selective.  

Similar to the last objection, but this gets more into the fact that even if prayers are answered there a certainly cases where one set of prayers are answered while another are not. Non-mormon’s might also wonder why extraterrestrials would select 15 men to receive the best communication of all. Are we to imagine that aliens are Christian? (Why not?)

I’m sure there are other objections, but for the moment let’s stop with that last one, because I think the answers are similar, and this point it may be best to turn to an examination of what we, as humans, do in a similar situation.

There are in the world, many tribes which have no significant contact with global civilization. And it’s instructive to examine how we have chosen to deal with them, but also to examine more broadly what is and isn’t acceptable behavior towards them.

The first thing that we obviously don’t do, and that no one has suggested doing, is giving them a huge dump of technology. Whether that would be, in the worst case, a bunch of guns and ammo, or in the most innocuous case a set of encyclopedias. At the moment, what we mostly do is leave them alone. Though in the not too distant past we would contact them, and while this risks getting into an argument on how best to deal with indigenous people and colonialism, etc. such contact actually was largely religious in nature. The first people to show up when a new people were found were missionaries. And what did they try to do? Give them instruction in morality, build schools, and convert them to Christianity.

Interestingly I can’t think of any science fiction novel where the aliens set up schools, or educated humans in the dominant galactic religion (though Childhood’s End is sort of in that vein.) I think this is largely because people expect religion to disappear at a certain point in a civilization’s development. (I know the Hyperion Cantos keeps religion around, but his treatment of Christianity is pretty appalling.) I’m not claiming that a book written along those lines isn’t out there, but I know of no well known book written along that premise. What we mostly see are mysterious communications, or ships showing up with unclear intentions. There are of course war-like aliens, and those stories map well with the way civilization has dealt with more primitive tribes, but if there are aliens and they’re bent on war then we’re already screwed.

Let’s instead turn towards looking at how the objections to prayer might look if we applied them to contact with previously uncontacted people. The first objection was that prayer wasn’t scientific. I imagine that there are numerous ways we could use to contact these tribes which would seem equally miraculous as prayer seems to us, and remember that they’re only a few thousand years behind us in technology. We could be dealing with aliens that are millions of years ahead of us.

The second objection is that prayer isn’t how aliens would contact us. Okay, now take that thought and for a moment imagine that you’re an anthropologist studying an uncontacted tribe. Imagine that any individual in this tribe could send you a message, which would be instantly translated into your native language, and the message would describe in a detail not even available in a written journal the person’s deepest concerns, and the whole of their inner life? Yes there would obviously be privacy concerns, but for the moment put that aside (or you could assume that the anthropologist is maximally benevolent.) Wouldn’t that be the ideal way to allow that tribe to make contact? I think so. Perhaps you disagree. But I would think that you could at least see where such a system might have some significant advantages.

The final objection is that prayer is selective. Well so are we. You could certainly imagine that you might decide to contact one group of the previously uncontacted people without deciding to open the floodgates and contact all of them. You might do this because this particular group was in danger, or if they had developed a certain level of technology, or if they asked for help, or if you were experimenting with a new method of making contact. There are all manner of reasons why you might leave one group alone while making contact with another.

My point is not that prayer is so obviously alien communication as to preclude any other possible explanation, anymore than I am arguing that Fermi’s Paradox is obviously proof of God, but given how little we actually know, and given the assumptions that we can safely make, it fits at least as well as any other explanation and in some ways even better.