Speaker 1: How would we know if we're living in a simulation,
Speaker 1: And what does that have to do with having a
Speaker 1: dream that you're a butterfly or John Lennon or Renee
Speaker 1: des Cartes or freezing yourself in a vat of liquid nitrogen?
Speaker 1: And how will we solve the problem that human bodies
Speaker 1: can't do space travel? Welcome to Inner Cosmos with me,
Speaker 1: David Eagleman. I'm a neuroscientist and an author at Stanford University,
Speaker 1: and I've spent my career studying the intersection between how
Speaker 1: the brain works and how we experience life. And what
Speaker 1: I'm going to talk about today is the possibility of
Speaker 1: living forever. What does that have to do with the brain?
Speaker 1: Would we want to live forever? And how could we
Speaker 1: get there? Humans have been obsessed with the idea of
Speaker 1: immortality for ages. As far back as documented history goes,
Speaker 1: there are stories of humans trying everything to unlock the
Speaker 1: secret to eternal life. In Arthurian literature, the Holy Grail
Speaker 1: was said to have miraculous healing powers and it would
Speaker 1: grant anyone who drank from it eternal youthfulness, and the
Speaker 1: ancient Egyptians they would painstakingly prepare the physical body for
Speaker 1: the journey to the afterlife, and they believed you were
Speaker 1: reborn again and again. And China's first emperor launched an
Speaker 1: obsessive search for the elixir of life, and that obsession
Speaker 1: continues and cultures all over the world today. While leaving
Speaker 1: a legacy is the only thing close to immortality by
Speaker 1: today's standards, Woodie Allen wanted the real thing. He said,
Speaker 1: I don't want to achieve immortality through my work. I
Speaker 1: want to achieve immortality through not dying. He said, I
Speaker 1: don't want to live on in the hearts of my countrymen.
Speaker 1: I want to live on in my apartment. So what
Speaker 1: are our options for achieving eternal life? Well, the first
Speaker 1: option has to do with medical innovations, such that we
Speaker 1: keep repairing things that go wrong with the body. And
Speaker 1: in fact, it's rumored that life insurance companies assume in
Speaker 1: their actuarial tables that children born now are going to
Speaker 1: live to one hundred and fourteen years old. And this
Speaker 1: is based just on extrapolating medical innovation curves. In other words,
Speaker 1: you take the pace of medical progress and you guess
Speaker 1: what things are going to look like in a century
Speaker 1: from now. But the fact is there are barriers to
Speaker 1: physical immortality, like aging and disease, and then of course
Speaker 1: there are accidents that can happen, like you fall off
Speaker 1: a cliff, where you get in a car accident, or
Speaker 1: a tornado gets you, or a volcano explodes, and on
Speaker 1: and on. So although we can continue to make improvements
Speaker 1: in medical science to expand the average lifespan, there's no
Speaker 1: real guarantee that your lifespan is going to be any
Speaker 1: better now. There's a second approach that some people have taken,
Speaker 1: and that's about making a throw to the future, when
Speaker 1: people will know things like.
Speaker 2: How to repair bodies.
Speaker 1: The issue is that we just don't know how to
Speaker 1: cure lots of problems now, but it's not impossible that
Speaker 1: two hundred years from now a lot of this stuff
Speaker 1: will be obvious. In two hundred years, we'll look back
Speaker 1: at our textbooks and we'll think, my gosh, how did
Speaker 1: we not know that? How did we not know that
Speaker 1: we can just reach in and tweak some things on
Speaker 1: the telomeres and cure cancer easily with a few zapps
Speaker 1: and essentially make ourselves live much longer, maybe forever. The
Speaker 1: problem is that this is in the future and not
Speaker 1: right now. And therefore we don't get any of the
Speaker 1: benefits of that. So the idea is, perhaps you could
Speaker 1: by pausing yourself now and rebooting yourself in that future.
Speaker 1: And that's the approach of a company called Alcore. Alcore
Speaker 1: is based in Arizona, and they have these giant silver
Speaker 1: tanks called doers that are filled with liquid nitrogen and
Speaker 1: they're kept at a temperature of negative one hundred and
Speaker 1: ninety six degrees celsius. So when you're expiring on your
Speaker 1: hospital bed, this company gets contacted either by your family
Speaker 1: or because you're wearing a special bracelet, and as soon
Speaker 1: as your heart stops, a team from Alcore rushes to
Speaker 1: your bedside and starts the deep freezing process. Then they
Speaker 1: transport your body to Arizona where they put it in
Speaker 1: the giant vat with the liquid nitrogen. And you actually
Speaker 1: have two choices here. You can freeze your entire body,
Speaker 1: or if you can't afford that, you can just have
Speaker 1: your head removed and just have your head frozen. Because
Speaker 1: while it's great to have your whole body, the real
Speaker 1: representation of who you are is theoretically just kept in
Speaker 1: the brain. Or suffice it to say, that's the densest
Speaker 1: representation of who you are.
Speaker 2: You just need the head.
Speaker 1: Now, as a side note, you might wonder how much
Speaker 1: this costs. Well, you don't actually have to pay anything upfront. Instead,
Speaker 1: you can modify your life insurance payment to make its
Speaker 1: payout to the company. So this allows you the possibility
Speaker 1: of living a second chapter. Now, if you're unfamiliar with
Speaker 1: this slice of the world, it will blow your mind.
Speaker 1: I visited al Core and met the then CEO, Max
Speaker 1: More for my television show The Brain, and I got
Speaker 1: to tour around the facility and it's quite striking. There
Speaker 1: are these giant silver vats of liquid nitrogen and they
Speaker 1: currently have two hundred and eight people stored in there,
Speaker 1: and the company has over fourteen hundred people who are
Speaker 1: signed up for the service, but they haven't died yet
Speaker 1: and they will eventually end up in these vats. Now,
Speaker 1: although scientists don't currently know how to unfreeze and revivify
Speaker 1: a body, the idea is that some generation in the
Speaker 1: future will figure that out. Maybe that's a century from now,
Speaker 1: or maybe that's a millennium. And then the idea is
Speaker 1: that the frozen person will awaken into a new world.
Speaker 1: So people who sign up for the service operate on hope.
Speaker 1: They're making a deep football throw into the future, hoping
Speaker 1: someone will be there to catch it, and some people
Speaker 1: choose to cryo preserve their pets. Also, the idea is
Speaker 1: that if you awaken to a completely new reality, that's
Speaker 1: likely to be disorienting, and if you have a familiar,
Speaker 1: fuzzy face by your side, that could be really nice
Speaker 1: and reassuring. Also, it turns out that Alcore allows you
Speaker 1: to have a small memory box to go along with
Speaker 1: your frozen body. And the reason I mentioned this is
Speaker 1: because sometimes people ask me to inscribe one of my
Speaker 1: books to them. But I recently got a really interesting
Speaker 1: request from a man who had just signed up for Alcore.
Speaker 1: He said he'd been moved by my book to the
Speaker 1: Brain and wanted to keep that in his memory box
Speaker 1: that goes along with the frozen body, so he'd have
Speaker 1: it in his new world when he gets rebooted. So
Speaker 1: he asked me to sign my book for his revivification
Speaker 1: in a century or two. In other words, I would
Speaker 1: sign the book to him for his re entry into
Speaker 1: the world sometime in the future. Now I've had a
Speaker 1: lot of cool requests to sign books for special occasions,
Speaker 1: but signing for someone who is possibly coming back in
Speaker 1: a couple of centuries. That was a new one for me.
Speaker 1: So here's what I wrote, Dear Steve, welcome back. I'm
Speaker 1: so curious what secrets the world has divulged now. Presumably
Speaker 1: the text books have been thoroughly rewritten, and the current
Speaker 1: understanding of science would intimidate and thrill a twenty first
Speaker 1: century mind. Presumably I am long gone and all that
Speaker 1: remains of me are fading echoes of my genetic code.
Speaker 1: But this book remains. It memorializes what we knew in
Speaker 1: the early part of the millennium. Like all snapshots of science,
Speaker 1: some notions will stale, while others will prove more durable.
Speaker 1: Whatever the case, these pages form a bridge. They allow
Speaker 1: me to talk with you as though we still live contemporaneously.
Speaker 1: They allow two brains to span an unknowably wide chasm
Speaker 1: of time.
Speaker 2: Enjoy the future, David.
Speaker 1: So that's the method of freezing yourself until biology is
Speaker 1: better understood. It's a hail Mary throw, and you don't
Speaker 1: know for sure that anyone's going to catch the ball.
Speaker 1: For all you know, society will have collapsed, and maybe
Speaker 1: your body is going to get cannibalized, or legislatively, something
Speaker 1: might happen in the future where all these frozen bodies
Speaker 1: don't get unfrozen, or we are long blown up in
Speaker 1: a nuclear war and there's nobody there to unfreeze you.
Speaker 1: But people who sign up for this figure that at
Speaker 1: least they have a non zero chance of something happening here,
Speaker 1: of getting to live a second chapter, and that's better
Speaker 1: than having one hundred percent certainty that you're going to die.
Speaker 1: But fundamentally, there's a problem that's probably intractable, which is
Speaker 1: that we are made of biological pieces and parts, and
Speaker 1: those things are going to wear down. Even if we're
Speaker 1: able to successfully unfreeze people, the ticking clock of aging
Speaker 1: will keep ticking, and we're always going to be racing
Speaker 1: against entropy. As the poet William Butler Yeates said, things
Speaker 1: fall apart, the center cannot hold, and this is what
Speaker 1: aging and death is. And that brings us to a
Speaker 1: question of how we might solve this for the long term,
Speaker 1: forever by just extracting the part of us that matters
Speaker 1: our consciousness. So could it be possible someday to upload
Speaker 1: our consciousness out of our brains and onto a different
Speaker 1: substrate like silicon and run it, and would that still
Speaker 1: be you.
Speaker 2: So here's the idea.
Speaker 1: Maybe the hardware of the brain, all these cells, that's
Speaker 1: not the important part. But instead it's the software of
Speaker 1: the brain that matters. In other words, the algorithms that
Speaker 1: are running. Maybe that's what makes a mind. Maybe it's
Speaker 1: the patterns by which these spikes, these zeros and ones
Speaker 1: are running.
Speaker 2: And if we could extract those.
Speaker 1: Massive patterns and reproduce them on something different, maybe that
Speaker 1: would be you.
Speaker 2: This idea is called computational equivalents.
Speaker 1: The idea is that the eighty six billion cells of
Speaker 1: the brain are just running algorithms that have been sussed
Speaker 1: out by mother nature over billions of years. But fundamentally,
Speaker 1: it's just code that's being run. And so the idea
Speaker 1: of computational equivalents is that it doesn't matter if you
Speaker 1: reproduce this system out of legos or tinker toys or
Speaker 1: ball bearings or silicon. If the system runs the same program,
Speaker 1: you will get the same consciousness.
Speaker 2: You will get you.
Speaker 1: Now, we don't know if the theory of computational equivalents
Speaker 1: is correct, but if it is, it implies that we
Speaker 1: could shift ourselves off the degrading biological substrate of our bodies,
Speaker 1: and with powerful enough computers simulating all these neural interactions,
Speaker 1: we could upload our consciousness and exist digitally, circumventing the
Speaker 1: inevitability of demise. That would be the single biggest leap
Speaker 1: in the history of our species, launching us into an
Speaker 1: era of transhumanism. Just imagine what it could look like
Speaker 1: to leave your body behind and wake up in a
Speaker 1: simulated world. Your simulated existence could look like anything you wanted.
Speaker 2: Programmers could make any virtual world for you. If you've
Speaker 2: ever wanted to fly.
Speaker 1: Or breathe underwater, or inhabit an alien planet, you just
Speaker 1: sign a contract for it, You pay, and that becomes
Speaker 1: your new existence. It's your simulation and your reality is
Speaker 1: up to you. And as a side note, we could
Speaker 1: in theory run virtual brains as fast or slow as
Speaker 1: we wanted, so in seconds of computing time, you could
Speaker 1: have thousands of years of experience. In fact, even if
Speaker 1: the cosmos were coming to an end tomorrow, the programmers
Speaker 1: could simulate a billion more years for you.
Speaker 2: In that time.
Speaker 1: So all that sounds great, but there are some technical
Speaker 1: and theoretical hurdles. The first one is the enormous difficulty
Speaker 1: of figuring out the secrets of the brain. And this
Speaker 1: is a problem that can't be underestimated.
Speaker 2: As much as.
Speaker 1: We've discovered about how the brain works, we are a
Speaker 1: long way off from understanding the big picture. It's a
Speaker 1: very tough problem. You've heard me mentioned before on this
Speaker 1: podcast that the brain is the most complex device we
Speaker 1: have ever discovered. It has almost one hundred billion neurons.
Speaker 1: Each of those is as complicated as the city of
Speaker 1: New York, and you've got detailed connections between them that
Speaker 1: number in the hundreds of trillions. So figuring out the
Speaker 1: algorithms running in the system, or even just scratching the
Speaker 1: surface of those is something that still, for the most.
Speaker 2: Part, has completely eluded us.
Speaker 1: Consider this experiment that a couple of my colleagues did
Speaker 1: in twenty seventeen. They asked, what would happen if we
Speaker 1: used our best neuroscience approaches to understand a simple microprocessor,
Speaker 1: just a computer chip. So if the brain is really
Speaker 1: like a giant, complex computer chip, let's see how far
Speaker 1: we can get by analyzing this very simple one. So
Speaker 1: they picked an Atari microprocessor from nineteen eighty one that
Speaker 1: ran donkey Kong. And it turns out that after measuring
Speaker 1: all the input and output signals from the chip and
Speaker 1: applying the type of analyses that we have in neuroscience,
Speaker 1: they couldn't say much of anything about the function of
Speaker 1: the chip. I mean, note that they all already knew
Speaker 1: what the chip accomplished, and they know how chips work.
Speaker 1: But when you're looking at a ton of zeros and
Speaker 1: ones streaming in and streaming out, it's really difficult to say, Okay,
Speaker 1: here's the algorithms that the chip is implementing. As the
Speaker 1: researchers put it in that paper quote. In the case
Speaker 1: of the processor, we know its function and structure, and
Speaker 1: our results stayed well short of what we would call
Speaker 1: a satisfying understanding. So figuring out what the brain is
Speaker 1: implementing may turn out to be really hard.
Speaker 2: So can we copy the brain?
Speaker 1: Well, we're nowhere close to copying the human brain because
Speaker 1: the detailed structure of it is so enormous. It's probably
Speaker 1: a zetabyte of data, which is maybe around a tenth
Speaker 1: of the computational capacity of our planet right now. But
Speaker 1: this is fundamentally just a technology challenge, and the way
Speaker 1: that things are going we will probably get there at
Speaker 1: some point. It may not happen in our lifetime, but
Speaker 1: it's essentially guaranteed to happen in the future as our
Speaker 1: computational power increases.
Speaker 2: Okay, but this brings us.
Speaker 1: To a tougher hurdle, which might be a theoretical one,
Speaker 1: which is, there may be physics happening in the brain
Speaker 1: that don't make it as easy as copy pasting a
Speaker 1: giant document.
Speaker 2: For example, the.
Speaker 1: Brain might be exploiting quantum mechanical effects, and if so,
Speaker 1: that means we can't pretend the brain is just a
Speaker 1: big clockwork machine. Quantum mechanics is the science of the
Speaker 1: very small. It explains the behavior of subatomic particles and
Speaker 1: how they interact with each other and with light. The
Speaker 1: thing is that it's extraordinarily counterintuitive, and it's not really
Speaker 1: anything like classical physics, and we have no idea how
Speaker 1: to build a.
Speaker 2: Quantum system the size of the brain.
Speaker 1: Now I'll just mention there are many scientists like Roger Penrose,
Speaker 1: who recently won the Nobel Prize, who suggest that there
Speaker 1: might be quantum mechanical effects in the brain, And there
Speaker 1: are many more scientists on the other side of the
Speaker 1: debate who say they think there aren't quantum mechanics in
Speaker 1: the brain, but I just want to note that we.
Speaker 2: Don't actually know.
Speaker 1: Some people make fun of the quantum mechanics approach and
Speaker 1: they say something like, well, quantum mechanics is mysterious and
Speaker 1: the brain is mysterious, so maybe they're the same thing.
Speaker 2: Ha ha, Okay.
Speaker 1: Skepticism is always warranted until something is demonstrated to be true.
Speaker 1: But science doesn't rule things in er out in advance
Speaker 1: of having enough data, So when it comes to quantum mechanics,
Speaker 1: we don't actually know yet. Part of the problem that
Speaker 1: people have excepting quantum mechanics is that it's poorly understood
Speaker 1: and it's relatively new for us humans. But remember that
Speaker 1: for mother Nature, quantum mechanics has been around from the beginning.
Speaker 1: And one thing that's clear is that if there's something
Speaker 1: mother Nature can take advantage of, she will. So maybe
Speaker 1: quantum mechanics has nothing at all to do with the
Speaker 1: brain or everything to do with the brain, but we
Speaker 1: can't rule it out yet. And if it turns out
Speaker 1: that the brain is not so straightforward but requires quantum
Speaker 1: effects or whatever we discover next century like super hyper
Speaker 1: quantum x effects, then this path of learning how to
Speaker 1: reproduce the.
Speaker 2: Brain might take much longer.
Speaker 1: Maybe we'll need quantum computers or something we haven't even
Speaker 1: thought of yet. And I want to mention a third
Speaker 1: technical hurdle to successfully uploading our consciousness, which is that
Speaker 1: the simulated brain has to be able to modify its
Speaker 1: own structure. This is what's known as brain plasticity. In
Speaker 1: some of my other episodes have been about this. The
Speaker 1: activity that runs through a brain modifies the brain.
Speaker 2: It changes the brain.
Speaker 1: That's why you have memory, for example, because everything you
Speaker 1: experience is actually changing the physical structure of your brain,
Speaker 1: so that activity runs through it differently. Next time, when
Speaker 1: you learn that the name of this part podcast is
Speaker 1: inner cosmos, that physically changes the structure of your brain
Speaker 1: so that when someone asks you, hey, what was the
Speaker 1: name of that podcast, your brain can retrieve that information.
Speaker 1: So we need to simulate not only the detailed structure
Speaker 1: of the brain to run the software, but we also
Speaker 1: need to understand the physics of the ongoing interactions and
Speaker 1: how it changes. For example, in the brain, you have
Speaker 1: the activity of transcription factors that travel to the nucleus
Speaker 1: and change gene expression. You have dynamic changes in the
Speaker 1: location and strength of the synapses, the connections between neurons,
Speaker 1: and so on. And unless your simulated experiences change the
Speaker 1: structure of your simulated brain, you could inform new memories.
Speaker 1: You'd have no sense of the passage of time. Your
Speaker 1: consciousness would be frozen at whatever point it was uploaded
Speaker 1: into the simulation. Under those circums stances, would there be
Speaker 1: any point to immortality? Okay, So let's imagine that two
Speaker 1: hundred years go by and we managed to surmount all
Speaker 1: those technical hurdles.
Speaker 2: We have enough storage.
Speaker 1: Capacity, we figure out any quantum effects, We make it
Speaker 1: so that the simulation self modifies based on its experience.
Speaker 1: So great, we're there, and in this future world, uploading
Speaker 1: our consciousness would be possible. Now what would that mean
Speaker 1: for the human species? Well, among other things, it would
Speaker 1: open up the possibility of getting to other solar systems.
Speaker 1: There are at least one hundred billion other galaxies in
Speaker 1: our cosmos, each of which contain one hundred billion stars.
Speaker 1: We've already spotted thousands of exoplanets orbiting those stars. There
Speaker 1: are planets that are like Earth in some way, and
Speaker 1: some of those have conditions quite.
Speaker 2: Like the Earth.
Speaker 1: But The impossibility lies in the fact that our current
Speaker 1: fleshy bodies will ever get to those exoplanets, because there's
Speaker 1: just no real way that we're going to be able
Speaker 1: to travel those kind of distances in space and in time.
Speaker 2: But uploading would allow us.
Speaker 1: To transfer our minds into bodies that are built for
Speaker 1: space travel, and that way we could travel between stars
Speaker 1: in between galaxies with a human mind and a titanium body. Also,
Speaker 1: note that with a simulated mind, you could pause the simulation,
Speaker 1: you could shoot it out into space and reboot it
Speaker 1: a thousand years later when it arrives at a planet,
Speaker 1: So it would seem to your consciousness that you were
Speaker 1: on Earth, you had a launch, and then you instantly
Speaker 1: found yourself on a new planet. In other words, if
Speaker 1: you could upload your brain into silicon, this would be
Speaker 1: equivalent to the physics dream of finding a wormhole that
Speaker 1: lets you get from one part of the universe to
Speaker 1: another in a subjective instant. Okay, so we've established that
Speaker 1: if the algorithms are the important part of what makes
Speaker 1: you who you are, rather than the biological physical stuff,
Speaker 1: then it's a possibility will someday be able to copy
Speaker 1: our brains and upload them onto Silica and run them there.
Speaker 1: But there's an important question here, is it really you?
Speaker 1: I was thinking about this the other day because Paul
Speaker 1: McCartney announced an upcoming song with vocals by John Lennon
Speaker 1: thanks to AI that brings Lennon's voice back to life.
Speaker 1: But even though John Lennon is out there singing new
Speaker 1: songs now and everyone's talking about his immortality, he doesn't
Speaker 1: get to enjoy it. John Lennon doesn't know that he's
Speaker 1: been brought back. It's just zeros and ones running on
Speaker 1: a computer. John Lennon doesn't get anything out of that.
Speaker 2: So even if there's.
Speaker 1: A suit for a complete simulation of you, is it
Speaker 1: really you? Or is it just zeros and ones? Well,
Speaker 1: I think this could be argued either way. For example,
Speaker 1: every night when you go to sleep, it's like you
Speaker 1: are turning off, and then the consciousness that awakens on
Speaker 1: your pillow in the morning inherits all of your memories
Speaker 1: and we say, yeah, I'm the same person who climbed
Speaker 1: into this bed last night. I turned off, and then
Speaker 1: I turn on again and it's me and I'm getting
Speaker 1: back to business. So maybe the process of transferring from
Speaker 1: your physical body to a computer is just like that
Speaker 1: where you open your eyes in the simulated world and
Speaker 1: you think, cool, here I am.
Speaker 2: Let's get back to business.
Speaker 1: But there's another way to look at this too, which
Speaker 1: is that possibly when some company scans your brain and
Speaker 1: then uploads you into the computer, that's not you at all.
Speaker 1: That's just a computer program that's running. That program happens
Speaker 1: to feel confident that it's you. It has all your
Speaker 1: memories and beliefs, and thinks that it was just there
Speaker 1: standing outside the computer in your body, but its existence
Speaker 1: inside the computer doesn't help you at all. Let's imagine
Speaker 1: you just paid a million bucks to this immortality company
Speaker 1: and they tell you, hey, it worked. You see this
Speaker 1: little coordinate moving around on the screen. That's you. You're
Speaker 1: living forever now. And then you leave the immortality company
Speaker 1: and you drive home and sit on the couch and
Speaker 1: your life is no different.
Speaker 2: You are still heading towards death.
Speaker 1: It's just that you know you've paid all this money
Speaker 1: so that some computer simulation has a good afterlife.
Speaker 2: But is that really you?
Speaker 1: Did you gain anything out of paying this one million dollars?
Speaker 1: The actual situation is that there are now two of you.
Speaker 1: It's not like your consciousness is split or something, because
Speaker 1: you immediately move off on different trajectories. With each new experience,
Speaker 1: your brain and the computer simulation's brain are becoming different,
Speaker 1: so it really is like two separate beings. Now, interestingly,
Speaker 1: there's a philosophical question here about the timing. If the
Speaker 1: company uploads a copy of your brain to the computer
Speaker 1: and you go home, then it definitely seems like you
Speaker 1: have not achieved immortality.
Speaker 2: But if the.
Speaker 1: Company kills you and turns on the computer one second later,
Speaker 1: then it's like a transfer. You've gone from being inside
Speaker 1: your body to being inside the virtual world. It's like
Speaker 1: waking up on your pillow. Now you may well say, yeah,
Speaker 1: but I'm not actually sure that's me inside the virtual world.
Speaker 2: It's like a recreation of me.
Speaker 1: But I'm dead. I just got killed by the company.
Speaker 1: But again, this is the situation when we turn off
Speaker 1: at nighttime and wake up again in the morning. And
Speaker 1: you can ask the same question about Captain Kirk beaming
Speaker 1: himself up in Star Trek. One moment he's standing on
Speaker 1: the surface of the planet, and then he gets completely disintegrated,
Speaker 1: and then he gets reconstituted inside the ship.
Speaker 2: But is that really him now?
Speaker 1: Inside the ship, or was he actually killed on the
Speaker 1: surface of the planet, torn apart into his constituent atoms
Speaker 1: and some identical version of his structure gets rebuilt, But
Speaker 1: it's a new creature, it's not really him. These are
Speaker 1: all thorny questions that philosophers and neuroscientists wrestle with. And
Speaker 1: there are versions of these questions, like does it matter
Speaker 1: if you capture just the structure of the atoms that
Speaker 1: make up Captain Kirk and reproduce that structure with new
Speaker 1: atoms in the spaceship or whether you take his actual
Speaker 1: atoms and push those through space and rebuild him from
Speaker 1: his original atoms? Does it make any difference? Did he
Speaker 1: die in either case and it's just a rebuild of him.
Speaker 1: And by the way, returning to this question of timing,
Speaker 1: if the company kills you one second before turning on
Speaker 1: your simulation, they can call that a transfer. But if
Speaker 1: they kill you one second after turning on your simulation,
Speaker 1: then it's murder because you have an independent existence from
Speaker 1: that computer program and they have just taken that away
Speaker 1: from you.
Speaker 2: So the timing matters.
Speaker 1: And what you can see is that these are all
Speaker 1: tough philosophical problems. Now we've been conjecturing over whether you
Speaker 1: could reproduce consciousness. But it's of course a possibility that
Speaker 1: all of this conjecture is not conjecture at all.
Speaker 2: Maybe we have had.
Speaker 1: These conversations a thousand years ago and already figured out
Speaker 1: the key to successfully transfer our consciousness into a simulation,
Speaker 1: and the idea is that our reality is actually already
Speaker 1: a simulation. Now thinking about these issues, this is not
Speaker 1: a new idea. Two three hundred years ago, the Chinese
Speaker 1: philosopher Tuang Tu wrote that he once quote dreamt, I
Speaker 1: was a butterfly, fluttering hither and thither to all intents
Speaker 1: and purposes. A butterfly. I was conscious only of following
Speaker 1: my fancies as a butterfly, and was unconscious of my
Speaker 1: individuality as a man. Suddenly I awoke, and there I
Speaker 1: lay myself again. Now I do not know whether I
Speaker 1: was then a man dreaming I was a butterfly, or
Speaker 1: whether I am now a butterfly dreaming that I am
Speaker 1: a man. And what this illustrates is the difficulty of
Speaker 1: knowing precisely what reality we're in. The French philosopher Ney
Speaker 1: Descartes wrestled with a different version of the same problem.
Speaker 1: He wondered, how could we ever know if what we
Speaker 1: experience is the real reality. So he proposed a thought experiment.
Speaker 1: He asked, how do I know that I'm not a
Speaker 1: brain in a vat? Maybe some scientists are stimulating that
Speaker 1: brain in just the right way to make me believe
Speaker 1: that I'm here and that I'm eating this delicious food
Speaker 1: and seeing these stunning colors, and I'm listening to this podcast.
Speaker 1: And Descartes concluded there might not be any way to know.
Speaker 1: But he also realized something else. There's some me at
Speaker 1: the center trying to figure all this out. So whether
Speaker 1: or not I'm a brain in a simulation, I'm pondering
Speaker 1: the problem. I'm thinking about this, and therefore there is
Speaker 1: some I that exists. Japons don't suis. I think therefore
Speaker 1: I am irrespective of whether I understand precisely what that
Speaker 1: I is. Now, the modern version of the brain in
Speaker 1: a vat question is how do I.
Speaker 2: Know if I'm living in a computer simulation?
Speaker 1: And in fact, some philosophers like Nick Bostrom have suggested
Speaker 1: that in fact, it is more likely that we are
Speaker 1: in a simulation than not. His argument is that once
Speaker 1: it becomes possible to create a computer simulation of reality,
Speaker 1: then it's likely that many such simulations would be created,
Speaker 1: and in this scenario, it is more probable that we
Speaker 1: are living in one of these simulations rather than the
Speaker 1: real reality. And in fact, there are several philosophical arguments
Speaker 1: that have been put forward to support this idea. One
Speaker 1: argument is that the universe appears to be exquisitely finely
Speaker 1: tuned for life, with the laws of physics being very specific,
Speaker 1: which suggests they might have been designed by an intelligent being.
Speaker 1: And while some people use this as an argument for
Speaker 1: religious creationism, some philosophers use this argument that we are
Speaker 1: perhaps the creation of a very convincing virtual reality, of
Speaker 1: a simulation.
Speaker 2: The question of whether we are.
Speaker 1: Living in a simulation seems impossible, at least at the moment,
Speaker 1: to know how to address scientifically, but it certainly seems
Speaker 1: like a possibility. I mean, we already know how easily
Speaker 1: we can get fooled into accepting our reality. Every night
Speaker 1: we fall asleep and we have these bizarre dreams, and
Speaker 1: while we're there, we believe in those worlds entirely, and
Speaker 1: then we wake up and we think, oh, that wasn't
Speaker 1: actually the real world.
Speaker 2: Now I'm in the real world. So we know that
Speaker 2: we are completely capable of.
Speaker 1: Being in simulations and believing them entirely. In other words,
Speaker 1: the mere existence of dreams may be sufficient evidence that
Speaker 1: it is possible we are living in a simulation. Now,
Speaker 1: if we are living in a simulation, could we escape
Speaker 1: from it like they do in the matrix? Or are
Speaker 1: we trapped in it? Would we have any power to
Speaker 1: change the simulation? What's the purpose of the simulation? Who
Speaker 1: exactly created the simulation? Okay, so those are tough questions
Speaker 1: and we really have no way of tackling them, But
Speaker 1: I want to pile on one more.
Speaker 2: I think there's an open.
Speaker 1: Question for us about the usefulness of immortality. Would you
Speaker 1: actually want to live forever? And let's say, with your
Speaker 1: uploaded brain on a new substrate, you don't even require sleep.
Speaker 1: So for four hundred years you're looking for ways to
Speaker 1: occupy yourself.
Speaker 2: Time can be painful.
Speaker 1: Imagine for hundreds of years you're looking for entertainment like
Speaker 1: the best new series on whatever the streamers are at
Speaker 1: that point, or you're scrolling through your social media with
Speaker 1: infinite scroll and it really is close to infinite. Maybe
Speaker 1: you actually reach the end of the Internet. Is there
Speaker 1: a time when you say, Okay, it's been four hundred
Speaker 1: and seventy years, I am ready to wrap this up now.
Speaker 1: So I'll give you a sense of this from a
Speaker 1: short story that I wrote my book sum So in
Speaker 1: this story, you become a famous medical visionary, and here's
Speaker 1: how it goes. You argue that there's no such thing
Speaker 1: as a natural death, and you raise millions to fund
Speaker 1: your research. You program computers to calculate all possible mutations
Speaker 1: of viruses before they happen, and you design prophylactic treatments
Speaker 1: against them. You compute the exact effects of every medication
Speaker 1: on the normal cycles of the body. Your aggressive anti
Speaker 1: death program is a success. After the final breath of
Speaker 1: an incurably ill elderly woman, you are able to announce
Speaker 1: that hers represented the last natural death. Great celebrations ensue.
Speaker 1: People begin to live forever, healing just as they would
Speaker 1: when they were young, free at last from the overhanging
Speaker 1: cloud of mortality. You are greatly admired, but eventually your
Speaker 1: success begins to lose its shine. People come to discover
Speaker 1: that the end of death is the end of motivation.
Speaker 1: Too much life, It turns out is the opiate of
Speaker 1: the masses. There's a noticeable decline in accomplishment. People take
Speaker 1: more naps, there's no great rush. In an attempt to
Speaker 1: salvage their once dynamic lives, people begin to set suicide
Speaker 1: dates for themselves. It is a welcome echo of the
Speaker 1: old days of finite life spans, but superior because of
Speaker 1: the opportunity to say goodbye and complete your estate planning.
Speaker 1: That works well for a while, rekindling the incentive to
Speaker 1: live strongly, but eventually people begin to take the system
Speaker 1: with less than the appropriate seriousness, and if some large
Speaker 1: new development occurs, such as a new relationship, they simply
Speaker 1: postpone the suicide date. Whole cadres of procrastinators grow. When
Speaker 1: they reschedule a new date, others ridicule them by calling
Speaker 1: it a death threat. There develops enormous social pressure to
Speaker 1: follow through with the suicides at long last. After many
Speaker 1: abuses of the system, it is legislated that there's no
Speaker 1: changing a preset death date, But eventually it comes to
Speaker 1: be appreciated that not just the finitude of life, but
Speaker 1: also the surprise timing of death is critical to motivation,
Speaker 1: So people begin to set ranges for their death dates.
Speaker 1: In this new framework, their friends throw surprise parties for
Speaker 1: them like birthday parties, except they jump out from behind
Speaker 1: the couch and kill them. Since you never know when
Speaker 1: your friends are going to schedule your party, it reinstills
Speaker 1: the carpae dm attitude of former years. Unfortunately, people begin
Speaker 1: to abuse the surprise party system to extinguish their enemies
Speaker 1: under the protection of necro legislation. In the end, great
Speaker 1: masses of rioters break into your medical complex, kick the
Speaker 1: plugs out of the computers, and once again have a
Speaker 1: great celebration to mark the end of the last unnatural life. So,
Speaker 1: although there's been a millennia long reach for immortality, I
Speaker 1: think it's worth exploring this question of would it be
Speaker 1: worth it?
Speaker 2: So let's wrap this up for today.
Speaker 1: In the coming years, we are going to discover more
Speaker 1: about the human brain than we can describe with our
Speaker 1: current theories and frameworks. And at the moment we are
Speaker 1: surrounded with mysteries, many that we recognize and many we
Speaker 1: haven't even yet registered as a field. We have vast
Speaker 1: uncharted waters ahead of us. As always in science, the
Speaker 1: important thing is to run the experiments and assess the results.
Speaker 1: Some of the approaches are going to be blind alleys
Speaker 1: and others are going to move us farther down the
Speaker 1: road of understanding the blueprints of our own minds and consciousness.
Speaker 2: But one thing is certain, which.
Speaker 1: Is that our species is just at the beginning of
Speaker 1: something and we don't fully know what it is and
Speaker 1: where it's going. We are at an unprecedented moment in history,
Speaker 1: one in which brain, science and technology are co evolving,
Speaker 1: and what happens at this intersection is poised to change
Speaker 1: who we are and how we think about life and immortality.
Speaker 1: For thousands of generations, humans have lived the same life
Speaker 1: cycle over and over. We're born, we control a fragile body,
Speaker 1: we enjoy a small strip of sensory reality, and then
Speaker 1: we die. And science might give us the tools to
Speaker 1: transcend that evolutionary story, because we can now hack our
Speaker 1: own hardware, and as a result, our brains don't need
Speaker 1: to remain as we have inherited them. If we are
Speaker 1: able to upload our consciousness, eventually we're gonna be able
Speaker 1: to shed our physical forms altogether. So our species is
Speaker 1: just now discovering the tools to shape our own destiny,
Speaker 1: and who we become is yet to be Imagined. To
Speaker 1: find out more and to share your thoughts, head over
Speaker 1: to eagleman dot com slash podcasts and send me an
Speaker 1: email at podcast at eagleman dot com with questions or discussions,
Speaker 1: and I'll be making an episode soon in which I
Speaker 1: address those. Until next time, I'm David Eagleman, and this
Speaker 1: is Inner Cosmos