The Fermi paradox revisited

I am still thinking about Nick Bostrom’s stimulating essay (and Robin Hanson’s precursor essay).  Nick of course is worried about finding signs of alien life, which would suggest that life has arisen many times, leading to the question "where are they?" and the fear that life dies out pretty easily.  For Nick it is cheerier, from our point of view at least, to think it is very hard for life to get underway in the first place.

In pondering the Fermi question, I often wonder if I am not simply missing the party, so to speak.  Most people already *do* think they see signs of an alien presence of some kind, of course defining that concept broadly to include The Gods.  So how can we say we don’t see "them"?  Maybe I, the agnotheist, don’t see "them" (Him?) but surely most other people think they do.

Doesn’t that make the Fermi paradox go away in a snap?  No one cites Blind Boy Blake and screams "He doesn’t see them!".

Another way of putting it is to say we don’t take David Hume’s Dialogues on Natural Religion seriously enough.  We really have just one data point, so who can say what "they" look like, or what kind of "display" they would have made for us?

Alternatively, I am struck by the tension between the Fermi paradox with the "We are probably living in a simulation" claim.  Both are popular with the same group of people because they are nerdy ways of making you believe something weird; in reality the two conundrums don’t fit together.  If you take the simulation option seriously, you again see the creators all around you, albeit in disguised or cloaked form.  Of course you had to use Bayesian inferential reasoning to see them, but what’s wrong with that?  Better than a telescope, some would say.  And since most people believe in God, the creators might even consider their artwork to be already "signed."  (I’ll note rapidly in passing that the arguments against the simulation hypothesis also strike at the Fermi worries, but establishing that would take lots of work.)

Either way, it seems we see "them," or ought to think we see them, even if that turns out to be a visual mistake of sorts.

Addendum: I liked Michael Goodfellow’s point:

After that first species gets control, it makes all the rules.  If it shells over all the stars, no other life can even develop, since all the planets are frozen solid.  If it wants to let biological evolution continue, it can do that, by avoiding stars with fertile planets.  It can prevent any other technology from arising (by monitoring all the planets where life is evolving.)  It can guide or change any life that it does find.

This may seem horrible to you — little robots putting all the stars out!  Spreading like a weed and killing or preventing any new life from developing.  But you’re looking at it the wrong way…The first species out there gets to decide the future, for every species that follows.  For lack of any other evidence, let’s hope it’s us.

Splendid, but I part company at the last sentence.  There is some other evidence (of the Bayesian sort) and I think the most logical assumption is — whether you believe in God or space aliens — to think of ourselves as their product, one way or another.

Or to put it yet another way, what’s the principle of individuation here?  Isn’t "seeing us" and "seeing them" more or less the same thing?

Hail David Hume!


Goodfellow's point is only valid for high values of "control." In other words, it's circular; he's essentially saying, "After that first species gets sufficient control to make all the rules, it makes all the rules."

But why would we expect one species to accumulate that much control? If you substitute "nationality" for "species," it's clear that no nation has ever achieved that level of control over the world. The galaxy might be different, but why?

We have met the Other, and he is us? I am uncertain whether Walt Kelly would be proud.

I think the difference is that every nationality that the world has produced has been in constant contact with at least some other nationality. This has allowed technology to disseminate from nationality to nationality. Once one species gets out there moving from star to star (if this is even possible) it will be encountering species that have been on completely different development tracks. The only thing that comes close in the history of the Earth would be something like the period from the 1400's to the 1900's when the European powers developed technology that allowed them to move across the ocean and directly interfere with the affairs of cultures and nationalities that were several hops farther away on the dissemination ladder than had ever happened before. I would say that there are a lot of examples from that time where some nationalities got to set all the rules for at least a little while.
The experience of imperialism is missing a lot of the non-symmetries that a cross star systems meeting might include; thousands or tens of thousands of years difference in technology, orders of difference in brain mass, orders of difference in thought speed, etc.

As for the sim idea actually, I feel like the idea that this is a virtual reality, experienced exactly the same as if it were real, is fun but silly naval gazing: what difference does it make?

If we experience it the same then we experience it the same. If God is a computer nerd from 3500 AD, then thats "God". Maybe if you are 100% certain that science as currently understood and evolution is all there is, then this speculation would make a difference, but for those of us who don't know, it seems like just another God hypothesis without any real implications.

Also, as a metaphor, consider cancer. Any one of the mutations that lead to a given cancer are not that uncommon, but you require several before you actually have a tumor - and then one or more after that for it to become metastatic.

Similarly, the potential intelligent life requires several steps to become intelligent (a tumor) and one or more after that to become metastatic.

even if we are worthy of notice now, we haven't been worthy of notice for long at all. if the universe is effectively infinite (a silly assumption because of the logical problems it causes), it may just be taking other intelligent life a while to get around even noticing us (why assume we're worthy of notice at this stage? we're not much beyond talking dogs), let alone deciding to say hello. (the assumption that we can tell whether there's something out there is absurd -- we've been in this game for what, 50 years?)

Blind Blake. You are conflating him with Blind Boy Fuller.

Maybe the problem is that civilizations lose interest in space exploration before they overcome all the hurdles. After all, the assumption that there is a Great Filter is built on the notion that since humanity has explored much of the earth, all civilizations must want to explore space.

But Princeton astrophysist Richard Gott has a different idea, based on the Copernican Prinicple, which he explained recently:

"The Copernican answer to Enrico Fermi's famous question -- Where are the extraterrestrials? -- is that a significant fraction must be sitting on their home planets.''

It might seem hard to imagine that humans would invent rockets and then never use them to settle other worlds, but Dr. Gott notes that past civilizations, notably China, abandoned exploration. He also notes that humans have been going into space for only 46 years -- a worrisomely low number when using Copernican logic to forecast the human spaceflight program's longevity.

Since there's a 50 percent chance that we're already in the second half of the space program's total lifespan, Dr. Gott figures there is a 50 percent chance it will not last more than another 46 years. Maybe the reason civilizations don't get around to colonizing other planets is that there's a narrow window when they have the tools, population and will to do so, and the window usually closes on them. ''In 1970 everyone figured we'd have humans on Mars by now, but we haven't taken the opportunity,'' Dr. Gott says.

Even if we constrained our hypothesizing about advanced life forms to those that would continue to live at normal clock speed within our physical universe (non-accelerated, non-uploaded), they might still take forms that we cannot detect or recongize.

A sufficiently advanced living being might not necessarily be in compact, contiguous organic form: it could transform itself into a "steganographic" life form consisting of a network of diffuse nodes, communicating among themselves using encrypted spread-spectrum communications indistinguishable from background noise, with redundancy and error correction to ensure its integrity and survival. Such beings could conceivably exist on Earth or within the solar system right now, undetected. However, this scenario seems rather less likely than the "exodus from the slow physical universe" scenario.

What ethical principals do you assume these would come up with? My inclination is to see life as common, intelligence rare, and other intelligence as a source of fascination, perhaps suitable to enhancing progress for discovery and exploratory purposes. A universe less alone as a result, but one to keep tabs on in case they exceed your own.

I can't see what theism has to do with Fermi at all. Maybe I'm blind.

No name at 3:15: Even if all those points are true, if a civilization cared at all about the far future, it would want to send out probes to, if nothing else, gather negentropy that would otherwise have been uselessly dumped into space (by turning off the stars, building Dyson spheres and storing antimatter, or something else).

Sisyphus: Maybe all the dark matter in the universe is composed of suns and planetary systems trapped behind Dyson spheres, because there are so many intelligent beings out there. No need to worry about neutrino masses or other WIMPs if that's true.

Then why would so many stars be left un-sphered? Anyway, there's observed evidence for non-baryonic dark matter.

The "Great Silence" is taken to be evidence for lack of intelligent life because, so goes the argument, even if nearly all advanced civilizations were non-expansionist, it would only take one to "break the silence". However, we can't discount the likelihood that there is some transformation that all advanced civilizations go through which causes them to be silent. Not most or nearly all, but literally all.

Consider that about 10,000 years ago, all living humans were hunter-gatherers. Today, very few are, and in a few decades the only ones left will be in quarantined preserves like North Sentinel Island, cut off from all contact with the rest of humanity. Today, you are only a hunter-gatherer if every single one of your ancestors was. When people make the transition to agriculture and technology, they don't go back.

Consider the billion or so people living in the "First World" (US + Canada, Europe, Japan, Australia, etc). Not a single one of them would adopt a hunter-gatherer lifestyle. Even the most notorious Luddite of modern times, the Unabomber, lived in his log cabin at a level of technology and comfort higher than that enjoyed by the original European settlers of the American plains; even he chose to go back in time less than 150 years, not 10,000 years.

Likewise, even if there were a billion civilizations in our galaxy (a far too high estimate by many orders of magnitude), it is certainly possible that not a single one would continue the non-silent, expansionist way of life of their distant ancestors. We might not be able to fathom the reasons why, any more than hunter-gatherers can fathom civilization except through the distorted lens of cargo-cult mysticism, but that doesn't mean we can rule out such a possibility. And if any obstreperous one-in-a-billion would-be expansionists even existed, well then, much like some would-be hunter-gatherer dropout from civilization moving into a national park game preserve, they might be politely told by the neighbors to desist.

Why haven't all the stars in the galaxy been turned into Dyson spheres? I don't know... why hasn't every square inch of dry land on Earth been turned into farms? We simply can't fathom the purposes and motivations of truly advanced, possibly post-Singularity civilizations.

The "Great Silence" is evidence of... silence, not evidence of absence.

People ignore the most simple solution to the Fermi paradox. Maybe the distances involved are too great.

The most powerful radio signals ever made on our planet are only about 1% louder than background noise by the time they reach the nearest star. Just twelve stars away, an advanced civilization could be transmitting a million watt radio signal in all directions, and from here is is one millionth as loud as the radio signal from my wireless mouse.

There could be a million planets in our universe right now communicating as loudly as they possibly can, and our most sensative radio telescopes would never be able to pick one out from the typical background noise of the universe.

As far as actually traveling the distance, the answer is similarly obvious. Maybe the trip is impossible. Ever wonder why there are no polar bears at the South pole?

Why haven't all the stars in the galaxy been turned into Dyson spheres?

It's not that *all* have not been, it's that *none*, at lest in our immediate galactic neighborhood, have been.

I actually wrote and published a sci-fi novel based on the exact notion that Sisyphus hinted at - ie. that dark matter actually consists of many more stars and planets purposely hidden from us because highly advanced aliens are living on them and want us to remain oblivious to their existence. Details are on my website at

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