A battle between unknowns

I recently got into a discussion with a history-buff friend about the unfortunate fact that everything we know about history is incomplete -- and generally speaking, the further back in time you go, the more incomplete it is.  She referenced human remains like Tollund Man, the Lady of Caviglione, and the Egtved Girl, all European burials that have been extensively studied.  Tollund Man is the most recent (estimated at around 400 B.C.E.) and the Lady of Caviglione by far the oldest (at around 24,000 years ago), but all three share an aura of mystery regarding who they were, raising questions we almost certainly will never have answers to.  There's evidence Tollund Man was the victim of a sacrifice, but by whom, and toward what end, is unknown.  And about the circumstances of the other two, we know next to nothing.

Compound this with the fact that for every body that has survived, at least in skeletal form, literally millions more have crumbled into dust and are completely gone.  Most of our history is, and will always remain, lost.

The reason this comes up is the excavation in the Tollense Valley of Germany of the site of an ancient battlefield, dating to around 1250 B.C.E.  It was discovered in 1996 when an amateur archaeologist was walking along the edge of the Tollense River and saw something protruding from the bank.  It turned out to be a human bone -- and since that time, over 12,500 bones and 300 bronze arrowheads have been recovered from the area.  It appears to have been the site of one of the oldest known battles in Europe.  Some of the finds were downright gruesome:

The skull of one of the battle's casualties -- with the arrowhead that killed him still embedded in his cranium [Image credit: Volker Minkus]

What is most curious about the site is not that a bunch of people fought and killed each other -- after all, humans have been doing that pretty much forever -- but that an analysis of the arrowheads shows that the battle was between two groups, one of which had traveled there from hundreds of kilometers away.  The Tollense River Valley is in Mecklenburg-Western Pomerania, and about half the arrowheads are of a design known to occur in archaeological sites from that area; but the other half are clearly of a different make, matching designs from much farther south, in Bavaria and Moravia.

"This suggests that at least a part of the fighters or even a complete battle faction involved in Tollense Valley derive from a very distant region," said Leif Inselmann, of the Free University of Berlin, who co-authored the paper on the study, which appeared this week in the journal Archaeology.

Who they were, and what brought them northward and into conflict with the residents there, are unknown, although there are some speculative possibilities.

"A causeway that crossed the Tollense River, constructed about five hundred years before the battle, is thought to have been the starting point of the conflict," said study co-author Thomas Terberger, of the University of Göttingen.  "The causeway was probably part of an important trade route.  Control of this bottleneck situation could well have been an important reason for the conflict...  This new information has considerably changed the image of the Bronze Age, which was not as peaceful as believed before.  The thirteenth century B.C.E. saw changes of burial rites, symbols and material culture.  I consider the conflict as a sign that this major transformation process of Bronze Age society was accompanied by violent conflicts.  Tollense is probably only the tip of the iceberg."

The fact is, though, the rest of that iceberg is likely to remain forever underwater.  Who the people were that fought and died in the now peaceful river valley in northern Germany is very likely going to stay a mystery, as will the reason that drove some of them to make the long trip from the forests of Bavaria.  It behooves us amateur students of history to remember not only the old adage that "history is written by the victors," but that the vast majority of history is completely forgotten by both sides -- what we don't know about our own past far outweighs what we do know.

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Not magic

I got in a friendly argument online a few days ago with someone who finds my reliance on the scientific method "limited."  (His word.)

He accepts science, he said, but added that if that's your only way of understanding, there's stuff you'll miss.  "There are features of reality that science can't, or won't, study," he said.  "Science deals with what is tangible and quantifiable; there are other ways of knowing that allow you to access what is intangible and unquantifiable.  Without those, you're ignoring half of the universe."

The whole thing put me in mind of biologist Stephen Jay Gould's idea of non-overlapping magisteria -- that there are different domains of inquiry, and science only addresses one of them.  (Gould considered religion to be one of those other magisteria -- and that science and religion could coexist just fine unless one chose to tread on the other's toes.)

The problem with this is that science has been progressively chewing away at the other magisteria, as more and more of the universe is explained scientifically.  Phenomena that were thought to be utterly mysterious are now accounted for by rational scientific models -- heredity and tectonic activity are just two of many examples.  (In some realms -- such as legal documents -- we still have vestiges of this older way of thinking, in calling certain natural occurrences "acts of God.")

Even some religious people are uncomfortable with this approach.  Theologian Dietrich Bonhoeffer referred to it as "the God of the gaps," and pointed out the most obvious problem with it:

How wrong it is to use God as a stop-gap for the incompleteness of our knowledge.  If in fact the frontiers of knowledge are being pushed further and further back (and that is bound to be the case), then God is being pushed back with them, and is therefore continually in retreat.  We are to find God in what we know, not in what we don't know.

So accounting for a phenomenon using some not necessarily religious, but non-scientific, explanation is basically nothing more than the argument from ignorance; "we don't yet know how this works, so it must be beyond science to explain."

Emphasis on the word "yet."

Take, for example, the bleeding polenta of Padua.

[Image credit: Exploring the Invisible]

In 1819, there were reports of what some were calling a miracle and others a work of Satan -- the appearance of what seemed to be drops of blood in polenta, bread, and other starchy food.  Whatever it was did look convincingly like blood, as you can see from the above photograph.  Italy in the nineteenth century was a devoutly Roman Catholic country, and the phenomenon was considered a "sign" (of what, depended upon whom you asked; some thought it was a harbinger of the end of the world, unsurprising considering how often this claim still comes up).

But a chemist at the University of Padua, Bartolomeo Bizio, firmly believed that there had to be a natural, rational cause for the spots.  He obtained samples of the red-stained food, and very quickly discovered two things: (1) if he put a drop of the red material on a sterile dish of starch, it rapidly developed red streaks as well; and (2) when he looked at some of it under a microscope, he saw cells -- but not blood cells.  Whatever it was might have the same color as blood, but it wasn't blood.

It was, in fact, a bacteria, which Bizio named Serratia marcescens -- the genus name after Florentine biologist Serafino Serrati, and the species name from a Latin word meaning "decay."  The red color comes from an organic compound called prodiogiosin.  Serratia marcescens has been found to be a more-or-less ubiquitous bacteria in soils and on moist surfaces -- it's responsible for the pinkish color that sometimes shows up in spoiled food and around the edges of unscrubbed sinks and drains.

It's a simple example, but it does show how "it happened because of something supernatural" is not really an explanation at all.  It is, in fact, a way to stop thinking.  Bizio started from the standpoint of "let's assume this has a rational cause," and it was only because that was his baseline assumption that he was able to take the step forward into understanding it.

Now, don't misunderstand me; it's not that I'm sure that science can explain everything, and it's certainly not because I think science has explained everything.  It's more that before we jump to a paranormal answer, we'd better make sure we've ruled out all the scientific ones first.  Because in the past two hundred years, the other magisteria have gradually shrunk as science has explained more and more of the universe.

As the inimitable Tim Minchin put it: "Throughout history, every mystery ever solved has turned out to be -- not magic."

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Chutzpah

As always, Yiddish has a word for it, and the word is chutzpah.

Chutzpah means extreme self-confidence and audacity, but there's more to it than that.  There's a cheekiness to it, an in-your face, scornful sense of "I dare you even to try to do something about this."  As writer Leo Rosten put it, "Chutzpah is the guy who killed both of his parents and then appealed to the judge for mercy because he's an orphan."

The reason this comes up is, unsurprisingly, Mark Zuckerberg, who raises chutzpah to the level of performance art.  This time it's because of his interview last week with The Verge, which looked at his company Meta's embrace of AI -- and his sneering attitude toward the creative people whose work is being stolen to train it, and without which the entire enterprise wouldn't even get off the ground.  When asked about whether this was fair or ethical, Zuckerberg basically said that the question was irrelevant, because if someone objected, their work was of little worth anyhow.

"I think individual creators or publishers tend to overestimate the value of their specific content in the grand scheme of this," Zuckerberg said.  "My guess is that there are going to be certain partnerships that get made when content is really important and valuable.  But if creators are concerned or object, when push comes to shove, if they demanded that we don’t use their content, then we just wouldn’t use their content.  It’s not like that’s going to change the outcome of this stuff that much...  I think that in any new medium in technology, there are the concepts around fair use and where the boundary is between what you have control over.  When you put something out in the world, to what degree do you still get to control it and own it and license it?"

In other words: if you ask Meta not to use your intellectual property, they'll comply.  But not because it's the right thing to do.  It's because there are tens of thousands of other artists, photographers, and writers out there to fuck over.  Anything accessible on the internet is fair game -- once again, not because it's legal or ethical, but because (1) most of the time the creator doesn't know their material is being used for free, and (2) even if they find out, few creative people have the resources to sue Mark Zuckerberg.

He can just shrug his shoulders and say "fine, then," because there's a ton of other people out there to exploit.

Chutzpah.

Add to this an article that also appeared last week, this time over at CNN, and which adds insult to injury.  This one is about how Zuckerberg is now the fourth-richest person in the world, with a net worth of around two hundred billion dollars.

Let me put that in perspective for you.  Assuming no further increase in his net worth, if Mark Zuckerberg gave away a million dollars every single day, he would finally run out in 548 years.

Because of all this, it's only with deep reluctance that I still participate in Meta-owned social media sites like Facebook and Instagram.  Removing myself from them would cut me off completely, not only from opportunities to market my work, but from friends I seldom get a chance to see in person.  What are my other options?  The Elon Musk-owned far-right-wing cesspool formerly known as Twitter?  TikTok, which stands a fair chance of being shut down in the United States because of allegations of data mining by China?  I'm on Bluesky, but I'm damned if I can figure out how to get any traction there -- most of my posts get ignored completely.

You gotta give Zuckerberg one thing; he knows how to back people into a corner.

I know some of my bitterness over all this is how hard I've worked as a writer, and how little recompense I've ever gotten.  I've written Skeptophilia for twelve years, have over five and a half million lifetime hits on the site, and other than some kind donations (for which I will always be grateful) haven't made a damn thing from it.  I have twenty-odd novels in print, through two different traditional publishers and a handful that are self-published, and have never netted more than five hundred dollars a year from them.  I'll own some of this; I absolutely suck at marketing and self-promotion, largely because it was hammered into me as a child that being proud of, or even talking about, my accomplishments was "conceit," an attitude I've never really recovered from.  And fine, I'm willing even to accept that maybe I have an over-inflated sense of my own skill as a writer and how much I should expect to make.

So fair enough: I should admit the possibility that I haven't succeeded as a writer because I'm not good enough to deserve success.

And I could leave it there, except for the fact that I'm not alone.  As part of the writing community, I can name without even trying hard two dozen exceptionally talented, hard-working writers who struggle to sell enough books to make it worth their time.  They keep going only because they love storytelling and are really good at it.  Just about all of them have day jobs so they can pay the mortgage and buy food.

Maybe I can't be unbiased about my own writing, but I'll be damned if I'll accept that all of us are creating work that isn't "important or valuable."

So the fact is, AI will continue to steal the work of people like me, who can ill afford to lose the income, and assholes like Mark Zuckerberg will continue to accrue wealth at levels somewhere way beyond astronomical, all the while thumbing their noses at us simply because they can.  The only solution is one I've proposed before; stop using AI.  Completely.  Yes, there are undoubtedly ways it could be used ethically, but at the moment, it's not, and it won't be until the techbros see enough people opting out that the message will get hammered home.

But until then, my personal message to Mark Zuckerberg is a resounding "fuck you, you obnoxious, arrogant putz."  The last word of which, by the way, is also Yiddish.  If you don't know it, I'll leave it to you to research its meaning.

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Hit by the firehose

An impending astronomical event has brought to the general attention a phenomenon called a nova.  Misleadingly named after the Latin word for "new," a nova isn't a new star at all -- it's an old star (some of them very old) that suddenly flares up and becomes visible to the naked eye.  The nova in question is T Coronae Borealis, a star that is ordinarily around an apparent magnitude of +10 (making it far too faint to see without a telescope), but every eighty or so years flares up to a magnitude of around +2, becoming easily visible for a short time before fading to its original unimpressive luminosity.

Novas of this type are double star systems.  One member of the pair is a white dwarf -- the white-hot core of a Sun-like star at the end of its life -- and the other one is usually a giant.  What happens is that the super-dense white dwarf gradually siphons off gas from its larger but less dense partner, and as the gas falls onto the white dwarf's surface it heats and compresses, finally becoming hot enough to fuse into helium.  This releases more heat energy still, and causes a runaway chain reaction, resulting in the flare-up.  But the total amount of hydrogen available isn't really that great -- it's only a shell of material on the surface -- so the reaction runs out of steam, and the pair settles down again until enough more gas is siphoned off to trigger another flash.

T Coronae Borealis is due -- overdue, according to some astrophysicists -- for a blaze-up.  So those of you in the Northern Hemisphere, watch for this "new star" -- it's something you'll likely never get another chance to see.

The reason the topic comes up is some new data from the Hubble Space Telescope about novas in another galaxy -- M87, a supergiant elliptical galaxy in the constellation Virgo.  

[Image licensed under the Creative Commons Ngc1535, M87 Galaxy from the Mount Lemmon SkyCenter Schulman Telescope courtesy Adam Block, CC BY-SA 4.0]

M87 became famous because it was the galaxy whose massive central black hole became the first ever to be photographed.  Since then, it's been studied extensively, and the most recent information we've learned about it is downright puzzling.

Most black holes are surrounded by an accretion disk -- a violent whirlpool of gas spiraling down toward the event horizon.  As it spins, the ionized atoms release energy in the form of x-rays; some of them are accelerated enough to escape completely.  The result is a narrow jet of plasma and electromagnetic radiation, aligned with the poles of the black hole's magnetic field.

Especially with a supermassive black hole like the ones at the center of galaxies, having the jet aimed at you personally would be a very bad thing.  Anything less than a thousand light years away would be deep fried.  Even farther away, the effects of the plasma stream would be devastating.

And what the recent study found is that stars that are hit by this blast of radiation are much more likely to go nova -- and no one is really sure why.

"There's something that the jet is doing to the star systems that wander into the surrounding neighborhood. Maybe the jet somehow snowplows hydrogen fuel onto the white dwarfs, causing them to erupt more frequently," said astrophysicist Alec Lessing of Stanford University, who co-authored the study, in an interview with Science Daily.  "But it's not clear that it's a physical pushing.  It could be the effect of the pressure of the light emanating from the jet.  When you deliver hydrogen faster, you get eruptions faster.  Something might be doubling the mass transfer rate onto the white dwarfs near the jet."

The bottom line is, the astrophysicists are not sure why it's happening, but some interaction between the jet and the stars caught in it is making candidate stars "pop off like camera flashes."

I guess it's not surprising that when you put two of the most violent astronomical phenomena together -- the massive hydrogen bomb of novas, and the giant firehose of plasma from a supermassive black hole -- they behave in surprising ways.  The astrophysicists will be working their models trying to figure out just what exactly is going on here.

And for those of you who are worriers, M87 and its accompanying jets of radiation are a comfortable 53 million light years away.  Even our own galactic core is 26,000 light years away, and its radiation jets are aimed in a direction almost exactly ninety degrees away from us; the Solar System lies in one of the outer spiral arms, which are arrayed pretty much in a flat plane perpendicular to the rotational and magnetic axis of the galaxy.

So this phenomenon is certainly awe-inspiring, but it's not dangerous.  At least not to us.  As far as any inhabited planets caught in the outflow, well... good luck to them.

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The rules of the game

There's a lot of human behavior that, looked at from a perspective as if you were studying us from the outside -- say, as an alien anthropologist -- is mighty weird.

One example is our fondness for playing games.  We make up lists of often arbitrary rules, then individuals or groups compete against each other while following those rules to achieve some sort of goal -- which almost always is itself symbolic (other than professional sports and gambling, most games don't actually involve winning some sort of tangible reward).  Despite the fact that there's every reason to care very little about the outcome, from a very early age we learn to care deeply.  Many of us have the attitude imbued in me by my high school track coach -- "Second place is first loser" -- and that applies to everything from the Olympics to a game of Monopoly.

This drive is so strong that a lot of us become seriously invested in vicariously playing games by watching other people play them -- i.e., sports.  There have been fan riots when the home team doesn't win; people are willing to go on the rampage, destroying property and risking injuring others or themselves, because they're so angry that "their team" lost.  (A guy who's a friend of a friend once actually went outside and smashed a chair when the Buffalo Bills lost.)

And as I've written about before, the tendency to take sports extremely seriously isn't limited to the industrialized world.  The Mesoamerican ball games of the Classical Mayan civilization were deadly serious, and I mean that quite literally.

The losers were sacrificed to the gods.

Game-playing is one of those ubiquitous behaviors that's so common it's taken for granted, and is odd only when you think about it too hard -- but once you do, it seems so weird you have to wonder why it's nearly universal in all human cultures.  Sociologist Jonathan Haidt speculates that it's what psychologists call sublimation -- that it's a way of processing aggression harmlessly.  "Sports is to war as pornography is to sex," Haidt says.  "We get to exercise some ancient drives."

Whatever the explanation, there's no doubt that game-playing is not only widespread, it's very, very old.  A paper this week in the European Journal of Archaeology describes the discovery of what appears to be one of the oldest known examples of a board game, painted onto rock surfaces in what is now Azerbaijan.  The pattern is very similar to a game known from Ancient Egypt they called "Hounds and Jackals" (from the shapes of the game pieces).  The rules aren't known, but it appears to be a chase game, with potentials for pieces to jump ahead or get set back -- so perhaps a little similar to the familiar games of backgammon, parcheesi, and "Snakes and Ladders" (more commonly known in the United States as "Chutes and Ladders").

Two of the Azerbaijani game boards [Image credit: W. Crist and R. Abdullayev]

The archaeologists who authored the paper, Walter Crist of Leiden University and Rahman Abdullayev of the Minnesota Historical Society,  found six game boards (if that's what they turn out to be) at sites in Azerbaijan --  three at Ağdaşdüzü, and one each at Çapmalı, Yenı Türkan, and Dübəndi.  It's difficult to date stone artifacts accurately, but carbon dating of organic remains in the area suggests that they're about four thousand years old.  The similarity between all six strongly suggests that playing this particular game was widespread at the time -- and that the pattern would have been as as familiar and instantly recognizable to them as a Scrabble board is to us.

"Whatever the origin of the game of [Hounds and Jackals], it was quickly adopted and played by a wide variety of people, from the nobility of Middle Kingdom Egypt to the cattle herders of the Caucasus, and from the Old Assyrian traders in Anatolia to the workers who built Middle Kingdom pyramids," the researchers write.  "The fast spread of this game attests to the ability of games to act as social lubricants, facilitating interactions across social boundaries."

So board games have a very long history.  Gaming in general is certainly even older than that; artifacts that appear to be dice made of bone were found at Skara Brae in Scotland, and dated to around 3000 B.C.E.  So whatever drive it is that induces us to invent new ways to compete against each other, it goes back into our very distant past.

I'm not immune.  Whenever I'm in a competition, I get ridiculously invested in it.  I'm a runner, and have participated in various 5K and 10K races, and even though I know going in I'm not nearly good enough to come in first (or even first in my age category), I still get wicked frustrated when I have to run my finger halfway down the page of standings to find out where I finished.  And although I'm not a sports fan, all you have to do is get me involved in a game of Scattergories to find out how competitive I am.

Yes, I know the outcome doesn't matter.  But hey, if the people four millennia ago were that invested in playing Hounds and Jackals, at least I come by the tendency honorably.

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The mystery of the third man

In the episode of Star Trek: Enterprise called "Doctor's Orders," the ship is passing through a region of space suffused with a field that interferes with (and could be dangerous to) most humanoid brain function.  The ship's doctor, Phlox, is from a species thought to be immune to its effects, so the captain agrees to have the entire crew (other than Phlox) put into induced comas and place the ship on what amounts to auto-pilot, leaving Phlox to re-awaken the crew once they've traversed the hazardous region.

It soon becomes obvious, though, that Phlox isn't entirely immune himself.  He begins to hear knocking noises, as if someone or something is trapped in the walls of the ship.  He sees shadows and illusory movement -- at one point, nearly killing Captain Archer's dog, Porthos, who had escaped from the captain's quarters, thinking it's an intruder who is stalking him.  After a period of becoming increasingly nervous and paranoid, he encounters the Vulcan crew member T'Pol, who was not sedated, and she not only helps him run the ship but keeps him company, significantly reducing his emotional stress.

Things take a frightening turn when both of them begin to hallucinate -- and they find that the dangerous region has expanded, turning what would have been a two-week crossing into ten weeks.  Phlox and T'Pol confer, and after weighing the options, conclude that the only possibility is to go into warp, initially thought to be too risky because of the possible interactions between the field and the ship's warp drive.  In the end, they decide that there's no way either of them will survive another eight weeks of what amounts to progressive psychosis.  They engage the engines, and successfully cross the region and back into normal space.

But when Phlox goes around to re-awaken the captain and crew, he finds T'Pol asleep in her quarters.  She has, in fact, been in an induced coma the entire time -- his interactions with her, and the help and companionship he received, were also hallucinations.

What Phlox experienced is a strange, but well-known, phenomenon called the third man illusion.  This occurs when someone in a life-threatening situation has the overwhelming sensation of being accompanied by a supportive or comforting presence, often of a particular person.  The most famous example is Ernest Shackleton, who during his harrowing crossing of South Georgia Island with two others, was frequently convinced that there was a fourth there with them, someone who was a protector and would see them to safety (which, eventually, they accomplished).  Poet T. S. Eliot referenced Shackleton's experience in his poem "The Waste Land" -- in fact, it's Eliot's lines that gave the third man illusion its name:

Who is the third who walks always beside you?
When I count, there are only you and I together
But when I look ahead up the white road
There is always another one walking beside you
Gliding wrapt in a brown mantle, hooded
I do not know whether a man or a woman
— But who is that on the other side of you?

Unlike yesterday's post, where hallucinations during cataplexy were often disturbing or downright horrifying, the third man illusion is comforting, sometimes even giving the person in extremis information or encouragement that leads to their ultimate survival.

It probably should go without saying that I don't think the third man illusion is because there is an actual disembodied presence there with you, any more than the poor woman in my previous post who saw a "greenish-pale, abnormally tall man" shouting random numbers at her was seeing something real.  It's much more likely that like Phlox in "Doctor's Orders," our brains have created the sensation of something comforting or helpful as a coping mechanism to alleviate extreme stress.  But you have to wonder if this is where the whole Guardian Angel idea comes from -- that there is a being out there who is looking out for us, and helps us come safely through dangers.

But there's no doubt that it can seem one hundred percent real, and many of the people who have experienced it come away true believers.  Mountain climber Joe Simpson, in his 1988 book Touching the Void, describes falling into a crevasse in the Peruvian Andes and suffering a horrific leg injury, and that a "voice" encouraged him to keep trying and guided him to safety -- a voice that came from outside him, and without which, he says, he would have certainly died.

So who knows?  I've never experienced anything of the kind myself, so perhaps it's easy for me to sit here in my comfy chair and disbelieve.  It's hard, sometimes, to balance hard-nosed rational skepticism with "there are more things in Heaven and Earth, Horatio, than are dreamt of in your philosophy."  We certainly don't have explanations for everything.  As journalist Kathryn Schulz put it, "This is life.  For good and for ill, we generate these incredible stories about the world around us, and then the world turns around and astonishes us."

And... sometimes... may actually save our lives.

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Reality, nightmares, and the paranormal

I was giving some thought this morning to why I've turned into such a diehard doubter of paranormal occurrences.  And I think one of the main reasons is because I know enough neuroscience to have very little faith in my own brain and sensory organs.

I'm not an expert on the topic, mind you.  I'm a raving generalist, what some people describe as "interested in everything" and more critical sorts label as a shallow dilettante.  But I know enough about the nervous system to have taught a semester-long elective in introductory neuroscience for years, and that plus my native curiosity has always kept me reading about new developments.

This is what prompted a friend of mine to hand me the late Oliver Sacks's book Hallucinations.  I love Sacks's writing -- The Man Who Mistook His Wife for a Hat and Musicophilia are tours de force -- but this one I hadn't heard of.

And let me tell you, if you are the type who is prone to say, "I know it happened, I saw it with my own eyes!", you might want to give this book a read.

The whole book is a devastating blow to our confidence that what we see, hear, and remember is reality.  But the especially damning part began with his description of hypnopompic hallucinations -- visions that occur immediately upon waking.  Unlike the more common hypnagogic experiences, which are dreamlike states in light sleep, hypnopompic experiences have the additional characteristic that when you are in one, you are (1) convinced that you are completely awake, and (2) certain that what you're seeing is real.

Sacks describes one of his own patients who suffered from frequent hypnopompic hallucinations. Amongst the things the man saw were:

• a huge figure of an angel
• a rotting corpse lying next to him in bed
• a dead child on the floor, covered in blood
• hideous faces laughing at him
• giant spiders
• a huge hand suspended over his face
• an image of himself as an older man, standing by the foot of the bed
• an ugly-looking primitive man lying on the floor, with tufted orange hair

Fortunately for him, Sacks's patient was a rational man and knew that what he was experiencing was hallucination, i.e., not real.  But you can see how if you were even slightly inclined to believe in the paranormal, this would put you over the edge (possibly in more than one way).

But it gets worse.  There's cataplexy, which is a sudden and total loss of muscular strength, resulting in the sufferer falling to the ground while remaining completely conscious.  Victims of cataplexy often also experience sleep paralysis, which is another phenomenon that occurs upon waking, and in which the system that is supposed to re-sync the voluntary muscles with the conscious mental faculties fails to occur, resulting in a terrifying inability to move.  As if this weren't bad enough, cataplexy and sleep paralysis are often accompanied by hallucinations -- one woman Sacks worked with experienced an episode of sleep paralysis in which she saw "an abnormally tall man in a black suit...  He was greenish-pale, sick-looking, with a shock-ridden look in the eyes.  I tried to scream, but was unable to move my lips or make any sounds at all.  He kept staring at me with his eyes almost popping out when all of a sudden he started shouting out random numbers, like FIVE-ELEVEN-EIGHT-ONE-THREE-TWO-FOUR-NINE-TWENTY, then laughed hysterically."

After this the paralysis resolved, and the image of the man "became more and more blurry until he was gone."

Johann Heinrich Füssli, The Nightmare (1790) [Image is in the Public Domain]

Then there are grief-induced hallucinations, an apparently well-documented phenomenon which I had never heard of before.  A doctor in Wales, W. D. Rees, interviewed three hundred people who had recently lost loved ones, and found that nearly half of them had at least fleeting hallucinations of seeing the deceased.  Some of these hallucinations persisted for months or years.

Given all this, is it any wonder that every culture on Earth has legends of ghosts, demons, and spirits?

Of course, the True Believers in the studio audience (hey, there have to be some, right?) are probably saying, "Sacks only calls them hallucinations because that's what he already believed to be true -- he's as guilty of confirmation bias as the people who believe in ghosts."  But the problem with this is, Sacks also tells us that there are certain medications which make such hallucinations dramatically worse, and others that make them diminish or go away entirely.  Hard to explain why, if the ghosts, spirits, et al. have an external reality, taking a drug can make them go away.

But the psychics probably will just respond by saying that the medication is making people "less attuned to the frequencies of the spirit world," or some such.  You can't win.

Nota bene: I'm not saying ghosts, or spirits, or the afterlife, don't exist or, even more, can't exist.  Just that there's an alternate plausible explanation for these experiences that relies on nothing but known science.  As skeptic Robert Carroll put it, "Before you accept a paranormal or supernatural account of the world, you had better make sure that you've ruled out all the normal and natural ones first."

In any case, I highly recommend Sacks's book.  (The link to the Amazon page is posted above, if you'd like to buy a copy.)  It will, however, have the effect of making you doubt everything you're looking at.  Not that that's necessarily a bad thing; a little less certainty, and a little more acknowledgement of doubt, would certainly make my job a hell of a lot easier.

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