We often speculate about what would happen
if an alien civilization visited us, but what if one already has? So today our main topic is the idea that ancient
alien civilizations might have visited us, and influenced our civilization at some point
in the past. This is a bit of tricky topic because on the
one hand, we have tons of really half-baked examples in this category of Fermi Paradox
Solutions, while on the other, it’s actually one of the logically stronger examples. The Fermi Paradox, the seeming contradiction
between the ancient immensity of the Universe and how we seem to be it's only inhabitants,
has tons of proposed solutions. Here at SFIA we generally break them down
into 4 main categories. The first is that intelligent technological
life just emerges far less often than we tend to assume or doesn’t last long, the second
is that it’s common enough but we just aren’t seeing it, and the third is that it is common
and we do see it, but we just don’t recognize it or believe the evidence. The fourth is our miscellaneous category for
those that overlap two categories or don’t fit in. Now we walked through all of these and their
subcategories in the Fermi Paradox Compendium, and there are a lot, even by just giving a
passing look at them that episode still clocks in at over 70 minutes, our longest episode,
and the second longest is the original version of that episode. It would probably be beneficial to have seen
at least one of those before watching this, though I will recap major points. Over the last couple years we’ve tried to
give most of the major solutions their own episode and indeed category 1, that civilizations
are rare, has its own series here, the Great Filters, which in fact only covers part of
that category. And to a degree so does Category 2, that we’re
not seeing them, in the somewhat tongue-in-cheek Alien Civilization Series. However we tend to skip over category 3 a
lot, and that’s mostly because it’s awkward. The basic theories are actually entirely fine,
and as reminder those subcategories are: 3A – Aliens are here but in secret
3B – Aliens visited our ancestors, our main focus for today
3C – Aliens are here but we can’t tell And 3D – We are actually aliens. There is a lot of overlap in these categories
too, but 3A, that they are secretly among us, differs from 3C, that they are here but
we can’t tell, in that 3C isn’t implying any attempt at hiding or deception, or even
necessarily that they aren’t from Earth, a sentient rock or tree or cloud we just don’t
even recognize as having a mind would be an example, or critters not from space but from
some semi-overlapping parallel reality. 3A on the other hand is our UFOs and little
green men category. Alternatively 3B, Ancient Aliens, is not exclusive
of 3D, that we are aliens, since we might be a left over colony. That was a fairly popular theory back before
we had a solid understanding of DNA and a complete enough fossil record to show that
all life here almost certainly has common descent to something billions of years back. You can’t be a descendant of the aliens
of Tau Ceti because we can show that not only are you and I distantly related to our cats
and dogs, but they can’t be from Tau Ceti either because we can track fossils back to
show that common ancestor was here. Of course it doesn’t exclude an alien colony
setting up shop here billions of years ago, but then they either must have left uncolonized,
some stopped in just to plant a flag and sneezed, leaving only a couple bacteria behind, or
having been wiped out so spectacularly that only microorganisms survived. It also still leaves the door open to panspermia,
the notion that the first life on Earth might have arisen not from tidal pools or oceanic
thermal vents but from comet impacts where the comets housed bacteria or at least chemical
building blocks for bacteria. One of the things we would like to do when
going to other places in our solar system is to look for evidence of life. If we find life in those places and it is
made of the same building blocks as life here, like using DNA, RNA and amino acids to make
proteins then that will strongly support panspermia. Recently in 2016, the team behind the Rosetta
comet landing mission reported that they had discovered the simplest of the amino acids. Earth organisms use glycine. In the dust surrounding the comet 67P we also
found glycine. This was a confirmation of the first detection
of glycine found during NASA’s Stardust mission that flew by Comet Wild 2 in 2004. Now, before we get all excited about panspermia,
we did not discover other amino acids we use and, unlike other amino acids, glycine is
the only one that has been shown to be able to form without liquid water. So, this might be nothing more than a molecule
that occurs in the mixture of organic molecules we find in and around comets. One amino acid, an organism does not make. Even so, we do not have a very clear picture
of how life initially arises from inanimate material, called abiogenesis, beyond that
it should rather obviously require a decently rich soup of appropriate chemicals and an
energy input. So all our theories on that are just looking
for places where that occurs and trying to guess how common they were on the early planet
and which might have been the more probable life-bearing soup. The only two problems with the notion that
we might be transplants from another planet are that first, it just moves the origin issue
back, to an even more distant time and location, and second you need a transport mechanism. Whether that’s intelligent or natural, it
leaves a big question mark as to why the galaxy isn’t teeming with life. Which, of course, is the whole problem with
the Fermi Paradox in the first place. It’s not a very good Fermi Paradox solution
if it just leaves you with the same problem. The Fermi Paradox is presumably not a real
paradox, folks leave comments about that sometimes so I feel obliged to state the obvious, we
assume there’s an entirely logical solution that would make it non-paradoxical. Most solutions proposed do not do a great
job at that, and many just pass the buck, but some actually exacerbate it. We try to look at the problem from the perspective
of known science and technologies that are reasonably plausible under that science. Folks will often suggest some science or tech
that would seem to solve the problem, after all we are very new to science and new theories
are abundant, but most actually make it worse. Faster than Light Travel, time travel, travel
to parallel universes, technologies that can create or convert energy even better than
fusion or antimatter, or thermodynamics bending technology like a perpetual motion machine
all make exploring, traveling, and colonizing the galaxy easier, which does not help with
the Fermi Paradox. If you assume civilizations have warp speed
travel then the option that they haven’t colonized the galaxy relies entirely on a
matter of preference, and extinction becomes ludicrous, they will have had some remnant
or distant isolationist colony survive anything that brought them down, and on astronomical
timelines even a handful of folks can breed back up a galactic civilization. This is a big problem for everything in our
category 2 and 3, and most of the miscellaneous ones in 4 as well, but it’s especially lethal
for 3D, the idea that we’re descendants of aliens. 3C, that we can’t recognize them as intelligent,
smart clouds or rocks or trees, suffers from other problems we discussed in the Compendium,
mostly 1 big problem for the theory and 1 big problem in discussing it. The problem with the theory is that, in a
nutshell, intelligence can recognize other intelligence. Assuming your intelligence evolved, it did
so because it served a practical purpose in aiding your survival, which for higher intelligence
means having tools and altering your environment, you don’t really need a high-abstraction
thought process for quick dodging of predators, indeed it actually tends to hinder that as
we’ve discussed before, conscious thought can slow you down. The kind of intelligence that would tend to
lead to civilizations and technology are the kind that form a group to spot wolves to defend
against them or hunt them instead. Those tools and alterations are noticeable
and easily recognized as artificial on the whole. The other problem, in us discussing it, is
that you can’t really prove or disprove it. I don’t know how to disprove that a rock
is intelligent or that there’s a parallel Earth, like some fey realm of fairies and
leprechauns, that we can’t detect. Same as the Simulation Argument or the notion
that reality might be a dream, you can’t prove or disprove it, so discussing it tends
to be fairly futile. Falsifiability is important in theories, not
just for good science, but because generally that which can’t be falsified or proven
typically has no obvious bearing on our existence anyway. That leaves us 3A, aliens among us now, and
3C, aliens among us way back. Needless to say both could be true, they aren’t
exclusive. And for that matter, while I don’t give
it a category, these sub-categories exist under the assumption that there aren’t aliens
hanging around openly and publicly on Earth anyway. That’s sort of the point of the paradox
in the first place, but we can’t actually rule out that you and I might simply be insane,
that your neighbor has green skin, has a UFO in their driveway, is not from Jupiter, Florida
but the actual planet, makes no secret of this, and you just filter it out. Considering lots of people seem to do this
with other things, that we do tend to accuse folks who follow category 3A of being unhinged
is probably rather unfair. Many of the other solutions require either
us or the aliens to have some behaviors that might be viewed by many as rather stupid or
crazy too. So this option probably shouldn’t be dismissed
too casually. Though, of course, the actual point is that
any theory which seems about as likely as personal self-deception or insanity probably
should be given no more weight than that option either. This is the reason we mostly skip 3A here. I don’t think people are nuts for believing
in UFOs, I just think they’re wrong. There are some crazy people who believe in
them, and there are some liars who claim they’ve seen them. But there are also crazy people who believe
the city of London exists and some liars who claim to have been there. Neither indicates that London does not exist
and does not get visited, nor is it particularly likely it doesn’t exist and I’ve somehow
fooled myself into believing it does. Quantity has a quality all of its own, for
some things, for science and for eyewitnesses, it’s less so. The problem is that people already know this,
but if you’ve had a flying saucer land in your front yard, or at least your memory indicates
that’s what it was, even if that wasn’t true, let’s be honest, you are probably
not going to believe evidence to the contrary. That doesn’t make you crazy or stupid. And since so many people say such things,
we tend to assume they can’t all be wrong or liars, and many folks find this reasoning
compelling. Many others do not, I do not, and I won’t
pretend otherwise but I won’t ridicule folks for that belief. It’s a pointless waste of time and mean-spirited
and I at least have more than enough bad karma to work off that I’d prefer spend my time
doing that rather than incurring more. So that’s basically 3A, it differs from
the others in that there is actually a ton of evidence supporting it, it just happens
to be very questionable and unlike the others, it’s a theory whose evidence comes from
the one place in the Universe we can easily examine, Earth in the here and now. All the others at least benefit from being
hard to examine. Even 3B, Ancient Aliens, at least benefits
from being in the past, and we are always digging up new bits of the past we didn’t
know about, sometimes whole civilizations. And of course 3B is our main focus for today,
which we should probably finally get to. Welcome to SFIA by the way, where we always
have a point but sometimes need an hour to get there! Hence why everyone is always encouraged to
grab a drink and snack before hitting play. 3B, Ancient Aliens, is actually not a bad
theory in and of itself, which is funny as it’s probably the most ridiculed. While it’s humorous and humble to suggest
nobody visits Earth because we’re boring or that advanced aliens give us no more regard
than we give ants, that’s all those are, humorous and humble. Ignoring that we have whole academic disciplines
devoted to studying ants or small groups of people in the wilderness, the key thing about
being hyper-intelligent is that you can multitask and learn a lot. For those of you who remember the Matrioshka
Brain we’ve discussed before, a computer powered by an entire star, that thing had
enough processing power to not only emulate the minds of every human on Earth, but enough
to do every single person in the entire Observable Universe. It could do so even if every single planet
in it, all the billions in this galaxy and billions of other galaxies, each had billions
of people on them. And that concept doesn’t even assume any
freaky new science. You might wonder what it would gain from talking
to us, but it’s quite capable of holding a simultaneous discussion with every person
alive without even noticing the processing power used for that. On the top of that, intelligence doesn’t
scale well. Humans don’t find ants interesting because
we’re relatively stupid, we find them interesting because we’re quite smart and curious. Nobody goes around saying they don’t study
parrots or cats or oak trees because they’re too smart to bother with such idiots. There’s no way to guess what an advanced
civilization would find interesting but you’d expect them to be more curious and inquisitive
than us, not the reverse. We have spoken about post-scarcity societies
on this channel before and one of the things that folks in post-scarcity societies would
be interested in is occupying their time with something meaningful. We already find it interesting to study the
microbes, plants and critters on our little planet. A civilization that has used all of the power
outputted by their star, a Kardashev 2 civilization, would presumably have members interested in
doing this too. Even if the average alien in a K2 civilization
was not particularly curious or inquisitive, even if 1% of 1% of their population was an
exception and was curious and inquisitive about other aliens, that would still add up
to billions of aliens scouring the galaxy tracking down inferior life. So the notion that someone visited Earth before
is not even a little bizarre, quite to the contrary it’s trying to explain away why
such civilizations may exist and haven’t visited here that’s problematic and one
of the big flaws with most category 2 solutions of the Fermi Paradox. We have to handwave in stuff like the Zoo
Hypothesis or Star Trek Prime Directive of non-interference with primitive life to explain
a lack of visits. In that regard, 3B, ancient alien visitors,
is difficult only because in the first place, you have to wonder why they stopped visiting,
and in the second, you have to wonder where all the evidence of those visits disappeared
too. That’s its only big flaw, and I should also
add that like most of our sub-categories it actually contains a ton of different solutions,
not all of which are “Aliens helped us build the pyramids” type. For instance a fairly common and reasonable
one is that Category 1 is more or less correct, that intelligent life is pretty rare, and
that the relative handful of civilizations that naturally emerged tend not to be very
expansionist but are curious. So they explore around and when they find
some species that looks like they might be on the right path they give them a nudge,
biologically or just some advice, something we call uplifting. Then they leave because they value intelligence
but also diversity, so they’ll give folks a hand with one of the last hurdles but they
then go wait by the finish line. They get to learn about us before they tinkered
with us, and then can get the notes from our own history when we get on the galactic stage,
which gives a good reason why they might show up in mythology a bit but are gone before
you have regular, solid record keeping. Once we get to the finish line they say hi,
give us a hand getting started, and encourage us to do unto others as they did unto us. We see something along these lines as the
galactic culture in David Brin’s Uplift Saga. They feel folks should mostly get there on
their own, skinned knees and all, but they’re not dogmatic about it and wouldn’t let an
asteroid wipe out a whole planet while standing on a soapbox about non-interference or worry
that some tribe in antiquity they visited thought they were gods, since they were just
as likely to make some up anyway, and after a few generations they’d be indistinguishable
from invented myths. This runs headlong into the Non-exclusivity
problems and Dyson Dilemma we’ve discussed before in this series, but so does pretty
much every other solution to the Fermi Paradox outside of Category 1, and not as bad as some
honestly. None of the Fermi Paradox solutions presented
thus far are really good, and I tend to subscribe to Category 1 not as the best solution, but
as the one with the least number of holes in it. If any of them were truly clear and convincing
we’d have dropped the Paradox phrasing. Another of the big problems with category
2 and 3 in general is they are very motivation based, something absent from category 1. This is obviously a big issue with non-exclusivity
since the whole point of that is that solutions that rely on universal behavior by every species,
and sometimes even every member of those species, tend to be rather dubious. There’s no particular reason to think that
you have to be capitalist or communist, democratic or totalitarian, religious or atheist to colonize
space, so solutions that only work if all aliens had one of those ideologies are pretty
dubious. But motivation also matters for ancient visitors
too because aliens showing up here in 3000 BC to get the pyramids rolling as a prelude
to a failed conquest is very different from ones who taught monolith building to encourage
astronomy down the road. Evidence and logic for each of those will
play out differently and they are exclusive and contradictory. Yes you can have multiple reasons for encouraging
folks to build something, and it can have multiple purposes, but they have to fit together,
and a thin bit of circumstantial evidence that Stonehenge was meant to be an observatory
is not enhanced by an equally thin argument the pyramids were meant to be landing pads
for spacecraft. A blurry image of the Loch Ness Monster is
not enhanced by a blurry photo of Bigfoot or a Leprechaun or a UFO. These are not related, but folks will tend
lump them together. Both ways too, proving a photo of Leprechaun
is fake has no bearing on if the Bigfoot photo is real, indeed it has no bearing on if other
Leprechaun photos are real too, but at least disproving one removes one piece of relevant
evidence to Leprechauns. People do that though, we tend to get a lot
of Inertia to theories as well, they collect bits of evidence, good or bad, but for those
fond of the theory the bad evidence might have helped sway them originally but it being
tossed out later doesn’t remove their confidence much. We’ve known for a long time that the pyramids
or various megaliths were quite buildable by the technology available to their builders,
and folks often would say how they did it was a mystery, because a given entirely scholastic
article would say so, but not because that scholar thought their existence was mysterious,
but because they weren’t sure which of a dozen plausible methods was the one used. So rather than pointing out that there were
a ton of ways they could have done it, and we just weren’t sure which of those they
used or maybe something else, that mystery gets kicked around as a total one, that we
have no clue how they did it at all, rather than which method. That Stonehenge Observatory option I mentioned
a moment ago has been kicking around for centuries and mostly derives from us not knowing why
they built something that was obviously very hard to build. In the 18th century it got noted that the
entrance faces the rising sun on summer solstice and astronomy has been important to many cultures
for both ceremonial and practical reasons, but they obviously didn’t build it to help
locate the where the sun rises for summer solstice, two heavy rocks with sharp points
lined up in that direction would do that job better and way easier. It may have had a ceremonial role related
to the movement of the heavens, but it wasn’t for keeping track of them, it would be massive
overkill and not very efficient either. Nonetheless some ceremonial role involving
astronomy is quite probable and we still don’t know. The difficult thing about a monument that
was in regular use for centuries during which there was no writing, is that the folks using
it might not have known the original purpose either. Some architect might have said it needs an
opening and thought it was nicely symbolic to put it lined up that way, even if it the
intended purpose was unrelated. Later generations might have taken to holding
meeting and ceremonies on summer solstice at dawn just because someone noticed that
feature and assumed it was the right and proper way to do things, then someone else could
have come along and assumed it was right and proper because it was a temple to the Sun
God, and if he left a carving of that sun god on a stone, painted green to symbolize
the sun nurtured plants, its discovery would set off a wave of folks convinced it was an
alien landing site. Additionally folks often don’t hear about
the disproven stuff, it’s not as exciting or just ignored as inconvenient. The pyramids have hosted endless theories
of this sort, like the Orion Correlation Theory, that Pyramids of Giza were aligned like Orion’s
Belt, one of whose stars was symbolic of Osiris, and the belt points toward Sirius, the brightest
star in the sky, or stars, it’s actually a binary, and which symbolized his wife and
sister Isis in Egyptian Mythology. And that if viewed from the South, small shafts
in the pyramids line up to view Orion and Sirius. Which would be perfectly fine, again our ancestors
took astronomy and monument building quite seriously and often did mesh them together. Except that those shafts do not line up with
those stars, the stars move as the Earth has a 26,000 year precession, and for that alignment
to fit, they’d have had to build the place in 10,000 BC, as opposed to 2500 BC, which
is a major reason for folks often arguing them to be much older. Honestly the theory was pretty nuts even in
1983 when it got proposed, though fit comfortably in with a lot of the other zanier pyramid
theories, but we still had a fairly limited pool of dating methods then and they were
often off by whole centuries, indeed often still are, but we have way more methods and
gotten way more accurate with them and this idea the pyramids are even more ancient than
established goes from the highly dubious to the downright nonsensical at this point. But it’s a recurring problem, theories can
start off fairly plausible from what we know, and can gain strength from age for many folks,
even though they’ve actually been getting cut to ribbons in the meantime. I should probably note also that people being
people, an awful lot of our monuments are ‘protected’ against much intrusive study
because the local government would prefer not to lose the tourist revenue, some of which
might dry up if the air of mystery was dispelled. It’s cooler to think maybe the Sphinx is
statue of an alien built 9,000 years ago than that King Khafra had a monstrous ego, and
the entire Sphinx Erosion Hypothesis that suggests an older age, dubious though it was
to begin with, as one should probably not trust erosion dating on artifacts people tend
to hang around and visit a lot, bypasses that none of the other junk lying around there
dates back further by any other means. And one handy thing about construction projects,
presumably alien ones too, is that folks do tend to leave garbage all over the place when
building them, including graffiti. Work crews building the great pyramid of Khufu
more than 4,000 years ago are believed to be behind graffiti markings in a hidden and
sealed chamber discovered by a robot called Djedi back in 2011. When I say old junk I’m not demeaning ancient
artifacts, just being literal, an awful lot of archeology is examining garbage because
we tended to cart off useful and working stuff whereas we usually buried or kicked dirt over
discarded broken pots or tools that couldn’t be repaired. You have to be careful of course, garbage
found at a site could predate it or come from someone visiting centuries later, and a lot
of dating processes can be thrown off by various things, so it’s a matter of applying many
different methods to many different objects and averaging things out. This is also true for astronomy too and why
distance to stars or their ages are often given with big uncertainty margins. Finding ways to narrow such things down is
just part of science and scholastics in general, and so is tossing out theories as evidence
contradicts them and moving to a new camp, rather than erecting a permanent home on the
site of a pet theory because it sounds cool. I want to emphasize that because one of the
reasons a lot of ancient alien theories persist is they often did emerge as entirely logical
and plausible theories when first introduced and when we knew less. They often gained a lot of publicity because
they sounded cool, and when the scholars packed up and moved to a new camp of thought, the
idea stuck around and gained lots of allegedly corroborating evidence. And it is fun too, some of my favorite stories
are ancient alien ones, I love the Stargate sci-fi franchise which bases entirely off
the idea that the pyramids were ancient alien landings pads. I also enjoy stories of the Trojan War and
the Iliad and Odyssey, but I don’t believe it actually happened that way, nor does the
discovery of Troy change that opinion. I’m also not blind to the notion that we
are indeed very good at manipulating evidence to paint the picture we want and that can
cut both ways, we could be tricking ourselves into assuming mundane explanations when they
are genuinely fantastic. But more importantly I’d emphasize that
this doesn’t actually hurt the Ancient Alien theory for the Fermi Paradox. Them not building the pyramids doesn’t disprove
the idea any more than them not building Big Ben in London. It wouldn’t even disprove they were hanging
around there then and gave Imhotep some geometry lessons. Nor does it have relevancy to all the other
Ancient Alien theories which pop up in almost every culture, it just doesn’t offer any
proof they were or did. Again if they were anthropologically inclined
and wanted to avoid disrupting us in the long term, they might have intentionally relied
on our tendency to let stories grow and twist with each retelling, and to converge to certain
popular themes, to effectively erase their existence from our memory. I’ve also mentioned before that I don’t
like the theory because I feel it steals away some of our accomplishments, and distorts
our view of our ancestors, painting a false and diminished picture. Suggesting Newton or Da Vinci got help from
aliens or were aliens diminishes them and their achievements. The Iliad is a great tale but for my part
I’d like a more accurate view of what happened to the city, not to replace Homer’s Tale. It’s still good even if fictional, same
as Lord of the Rings. Fundamentally though that’s not an argument
against the theory, just a personal objection. Again the key weaknesses are about where those
visitors went, and any specific theory needs to answer why they were visiting rather than
staying, what they wanted to accomplish, and so on. It also has the evidence problem, and again
all the Fermi Paradox solutions have that, but while the past here on Earth is hard to
prove compared to the present, it is a lot easier than trying to poke around Mars or
Alpha Centauri for ruins. In that regard it’s got a higher burden
of proof to meet, since there should be evidence lying around. We don’t see any artifacts on Earth that
don’t decently match up to those nearby or seem excessive for their time and location,
we certainly don’t see any advanced materials or devices lying around. No atomic power sources or metamaterials or
impressive alloys or crystals or semiconductors. Those should be present. Their absence doesn’t disprove the idea,
but here, on Earth, where we can find evidence, it weakens the theory compared to other Fermi
Paradox Solutions where we can say “Well, there could be mountains of evidence just
not on this planet”. And at the same time it does still suffer
from those same problems most of the Category 2 options have. If aliens visited us, why did they stop? If we present a reason, like a desire for
non-interference, can we realistically assume this would hold solid for not just them, and
every member of their species, but every other species out there too? It’s easy enough to imagine aliens who might
pop by to satisfy their curiosity about us and maybe give a hand on a few things but
want to leave before causing too much long term disruption, but harder to assume everyone
feels obliged to follow that policy. And again, no matter how good a theory is,
from a logical standpoint, it has to have evidence. The logic is fairly okay but not great for
this theory, but the evidence is lacking. So ultimately, while Ancient Aliens is a pretty
fun theory and makes for great stories, it’s just not a good Fermi Paradox Solution, it’s
a decently logical theory with some circumstantial and dubious evidence that mostly just paints
a coating over other proposed solutions, since it still has most of the other flaws and features
of various category 2 solutions, but adds on the need to explain an absence of evidence
for it from the one place in the Universe we can most easily find that evidence. Next week we will be looking at Mind Uploading,
and some of the challenges and applications of that technology. We will also take a look a Dennis E. Taylor’s
new novel, the Singularity Trap, our June Book of the Month. The week after that we will return to the
Outward Bound series, to look at Colonizing Mercury. For alerts when those and other episode comes
out, make sure to subscribe to the channel. And if you enjoyed this episode, you can share
it with others or join in the conversation down below in the comments section or at our
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thanks for watching and have a great week!
