In the premiere episode of the second season, Morgan Freeman dives deep into this provocative question that has mystified humans since the beginning of time. Modern physics and neuroscience are venturing into this once hallowed ground, and radically changing our ideas of life after death. Freeman serves as host to this polarized debate, where scientists and spiritualists attempt to define "what is consciousness", while cutting edge quantum mechanics could provide the answer to what happens when we die. Eben Alexander, Bruce Greyson, Stuart Hameroff, Giulio Tononi, Christof Koch, and Douglas Hofstadter are interviewed.
The 21 grams experiment to determine the weight of the human soul is discussed. Next, Steve Potter's Hybrot is explained.
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The 21 grams experiment to determine the weight of the human soul is discussed. Next, Steve Potter's Hybrot is explained.
Thanks for watching. Follow for more videos.
#cosmosspacescience
#throughthewormhole
#season2
#episode1
#cosmology
#astronomy
#spacetime
#spacescience
#space
#nasa
#spacedocumentary
#morganfreeman
#lifeafterdeath
#istherelifeafterdeath
Category
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LearningTranscript
00:00What happens when we die?
00:09Do we simply cease to be?
00:13Or do we survive in some form?
00:18What is it that makes us unique conscious beings?
00:21It's the greatest mystery of existence, a problem seemingly too big for science to solve.
00:29But today, a cluster of biologists, physicists, and philosophers are closing in on the answer
00:36to the ultimate question. Is there life after death?
00:47Space. Time. Life itself.
00:54The secrets of the cosmos lie through the wormhole.
01:00Is death the end? Eternal silence? Blackness? Nothingness? Or is there a spark
01:19inside of us that lives on beyond our physical selves?
01:25Philosophers and scientists have puzzled over that question for thousands of years.
01:30It's the great mystery. One that sooner or later, we all have to face.
01:39One morning when I was six years old, my grandmother didn't wake up.
01:46Then or ever again.
01:48It was my first experience with death.
01:52How could she be here yesterday, but gone today?
01:57Was she gone forever? Or did some essential part of her live on?
02:08Christians and Muslims believe in a heaven for the just and a hell for sanity.
02:14Other religions see death as a transition to an existence on a higher plane,
02:19or to another life here on Earth. All of these beliefs have one thing in common.
02:25The body is just a vessel for the soul. And the soul is eternal.
02:33This is something many believe in their hearts. But is there a way to prove it?
02:38Or disprove it scientifically?
02:41Eben Alexander taught and performed neurosurgery at the Harvard Medical School for 15 years.
02:48In 2008, his career took an unexpected turn. One that would give him profound insight
02:55into the possibility of life after death. He contracted an extremely rare form of bacterial
03:01meningitis. And he was diagnosed with a rare form of meningitis.
03:07And fell into a deep coma.
03:09I think if you were trying to come up with an experimental model that would best approach
03:15human death, meningitis is perfect. Because what it does is it attacks the entire outer
03:21surface of the brain. These are horizontal images taken through my skull.
03:29And you can see the entire outer surface of the brain was coated with meningitis.
03:35These bacteria had gotten rid of all the glucose and now the only thing left to consume
03:41were my brain cells. And so my entire neocortex, that part of the brain that makes us human,
03:45was completely shut down.
03:47After seven days of virtual brain death, Alexander emerged from the coma.
03:53Miraculously, within a month, he was back to normal. But something happened to him while
03:59he was away.
04:01My first recollection from deep inside the coma was that I was, what I sometimes call
04:09the earthworm eye view of the world. Everything was kind of murky, brown, red, dark. I literally
04:17remember roots over my head. And I seemed to be there for a very, very long time. I
04:25had no memory whatsoever of my life. No words. My language was gone. I was certainly not
04:31aware of anything going on around me in the ICU room. And then in the midst of that, there
04:37was a little melody that was spinning in front of me. And it just started spinning and expanded.
04:43And it ended up clearing away all that ugly, foreboding, gross, muddy realm.
04:51And all of a sudden, I was coming up into this beautiful meadow. I had no body awareness.
04:57I had no arms, legs, or anything. But I was aware that I was a speck on a butterfly wing.
05:03Absolutely beautiful butterfly. And there were millions of other colorful butterflies
05:09looping and swirling all around us, all in this beautiful formation of flying.
05:15And then we left this universe and went out into what I now call the core.
05:23At first, it seemed infinitely huge and dark, although I was there with that beautiful,
05:33warm awareness of the divine, which was clearly what we were looking for.
05:39Basically, I recall the whole multiverse being out in front of me.
05:45It was very clear that love was a huge part of the constituent of that whole multiverse.
05:51Alexander had faced something that tens of thousands of people have reported.
05:57A near-death experience.
06:01Alexander had faced something that tens of thousands of people have reported.
06:07A near-death experience. Nearly all claim something that science has so far been unable to prove.
06:15That there is another existence beyond the one we know.
06:19This was something that was very difficult for me to explain from a neuroscientific standpoint.
06:27And the scientific side of me could not see how that could be.
06:31And yet, it was a very, very powerful, very powerful memory.
06:35I came up with several models having to do with neurophysiology and neuroanatomy.
06:40And the problem is, none of those models sufficiently explain the very powerful memories
06:47that I brought back with me from this experience.
06:51And I ended up at a point where I do not believe that there is a good neurophysiologic explanation for what happened to me.
07:03Eben Alexander's experience was profound and life-altering.
07:09But it is by no means unique.
07:15Bruce Grayson is a psychiatrist at the University of Virginia School of Medicine.
07:20He has investigated more than a thousand cases of near-death experiences.
07:27The consistent features of a near-death experience are a sense of profound peace and well-being,
07:34a sense of leaving the physical body, a sense of brilliant light, which seems to radiate warmth and unconditional love.
07:43Sometimes people report encountering other beings, including a deity of some kind.
07:48Sometimes they identify that deity as God or Christ, and sometimes they don't.
07:53They just say that there was this all-powerful being that they met.
07:56Many scientists dismiss these experiences as nothing more than hallucinations
08:01triggered by a brain undergoing immense physical stress,
08:05mostly due to the nerve cells being deprived of oxygen.
08:10Back in the 1970s, experiments by the U.S. Air Force inadvertently tested this idea.
08:18Scientists spun pilots in a centrifuge, subjecting their bodies to massive G-forces.
08:24It caused blood to drain to their feet and left their brains starved for oxygen.
08:31They invariably blacked out.
08:34When they awoke, some pilots reported seeing a bright light.
08:39Others said they left their bodies and looked down at themselves from above,
08:43experiences similar to those of people who have been to the brink of death,
08:48but lacking one key feature.
08:51In the period when they were losing oxygen, as they were losing consciousness,
08:55they had some features which bear some similarity to near-death experiences.
08:59However, they certainly didn't ever meet deceased loved ones or other entities.
09:05The problem with all of these physiological explanations
09:09is that they don't account for the complex thinking,
09:13the memory formation, the perceptions that take place
09:17when we know the brain is not capable of doing complex thinking.
09:22Are near-death experiences the final dream of a mind that's about to wink out of existence?
09:30Or are they a sign that there is something beyond death?
09:35Finding the truth requires nothing less than a scientific quest to discover the human soul.
09:43Is the soul a myth or one of the fundamental elements of the universe?
09:50For scientists, the question of life after death is inextricably linked with another question.
09:57What is consciousness?
09:59Where does consciousness come from?
10:02And where does it go when we die?
10:09Dr. Stuart Hameroff is the Director of Consciousness Studies
10:12at the University of Arizona.
10:15He's also a practicing anesthesiologist.
10:21Okay, everything is going to go real smooth.
10:23Just pick out a nice dream and you'll wake up feeling really, really nice.
10:32Under anesthesia, patients don't dream.
10:34Even though I said pick out a nice dream, we always say that.
10:36But there's no awareness, there's no awareness.
10:38There's no consciousness.
10:40Under anesthesia, patients don't dream.
10:42Even though I said pick out a nice dream, we always say that.
10:44But there's no awareness, there's no passage of time.
10:46Patients wake up, they don't know if they've been asleep for five minutes or five hours.
10:50Anesthesia takes away consciousness.
10:53The brain under anesthesia is quite active.
10:55And the difference is still somewhat mysterious.
11:00Years watching over patients in the operating room made Hameroff obsessed
11:04with understanding the link between brain activity and consciousness.
11:09Then, 15 years ago, he met the great British physicist Sir Roger Penrose.
11:16Together, they developed a radical new theory for how the brain works.
11:21A theory that has grown into nothing less than a scientific argument for an eternal soul.
11:28At its root are tiny structures inside our brain cells called microtubules.
11:34If you look inside a cell, you find structural components
11:37that are somewhat like the bones within our bodies.
11:41The microtubules develop literally a forest inside each cell
11:45which determines the architecture and the structure of the cell.
11:48We think microtubules are perfectly designed to be the cell's onboard computer
11:54and process information at the molecular level.
11:57Hameroff and Penrose argue that microtubules allow neurons
12:01and the brain as a whole to function as a quantum computer
12:05performing operations in a fundamentally different way from normal computers.
12:11So here we have a brain with two hemispheres.
12:14Most views of the brain are of a collection of individual neurons.
12:18When one neuron fires, it sends a signal to the next neuron at a synapse.
12:22That in turn causes that neuron to fire and that neuron causes another neuron to fire,
12:27much like dominoes.
12:29So for example, if a neuron fires here, it's going to trigger its neighbors to fire,
12:33sending signals through and around the brain.
12:36That's the classical view of how the brain works.
12:41In a conventional computer,
12:43signals move around from place to place along traceable paths.
12:50But the microscopic components of a quantum computer
12:53are connected via a mysterious process called entanglement.
12:58Some of us think that quantum processes
13:00play an important role in consciousness in the brain.
13:03So for example, if there's neuronal activity here,
13:06it may be coupled through quantum non-locality to processes over here.
13:10These neurons are connected, even though they're spatially separated,
13:14so that activity here instantaneously affects activity over here.
13:21Hameroff and Penrose argue that a change in the brain
13:24Hameroff and Penrose argue that a change in the microtubules in one brain cell
13:28can affect microtubules in another.
13:31But that's not all.
13:33Quantum theory claims that every single point in space,
13:37even empty space, can contain information.
13:41At the very fine structure of the universe,
13:44there is information, quantum information,
13:47not unlike these dominoes, so that we can have information
13:50up or down, here and here, but they're connected,
13:53so that something that happens here influences something here.
13:59This means the information in the microtubules can connect
14:02and become entangled with the universe outside the brain.
14:11So just like these two neurons may be entangled,
14:14it's possible that the information of consciousness of the whole brain
14:17is entangled and can exist in the universe at large.
14:22According to Hameroff, our souls are built from something
14:26much more fundamental than neurons.
14:29They are constructed from the very fabric of the universe.
14:35I think that consciousness, or its immediate precursor,
14:38we'll call it proto-consciousness, has been in the universe all along,
14:41perhaps from the Big Bang.
14:48All of this recalls the Buddhist and Hindu belief
14:52that consciousness is an integral part of the universe,
14:56and perhaps it is all there is in the universe.
15:02If consciousness is a quantum process,
15:05it may solve the mystery of what happens during near-death experiences.
15:11Let's say the heart stops beating, the blood stops flowing,
15:15the microtubules lose their quantum state.
15:18But the quantum information, which is in the microtubules,
15:22isn't destroyed, it can't be destroyed,
15:25it just distributes and dissipates to the universe at large.
15:29If the patient is resuscitated, revived,
15:32this quantum information can go back into the microtubules,
15:35and the patient says, I had a near-death experience,
15:38I saw a white light, I saw a tunnel, I saw my dead relatives,
15:41I maybe even floated out of my body.
15:44Now, if they're not revived and the patient dies,
15:47then it's possible that this quantum information
15:50can exist outside the body, perhaps indefinitely as a soul.
15:56Many scientists find it difficult to believe
15:59that the soul is a quantum computer hardwired into the cosmos,
16:03but Hameroff feels that research is slowly validating his claims.
16:08Quantum effects have recently been shown
16:12to control several important biological processes,
16:15from bird navigation to photosynthesis
16:18to the human sense of smell.
16:22So far, nobody has landed a serious blow to the theory.
16:26We're still very viable, and evidence continues,
16:29new evidence continues to support the ideas
16:32that we put forth 15 years ago.
16:35But the truth is, we still don't know
16:38where consciousness comes from or where it goes when we die.
16:43If there was a way to measure consciousness,
16:46perhaps we could find the answers to these questions.
16:50That way may be coming soon,
16:53as one scientist explores the depths of our minds,
16:56hoping to discover the mysterious mental pattern
16:59that makes us who we are.
17:03The human brain isn't very big,
17:06three pounds of soft tissue,
17:09but it can generate ideas that transform the world.
17:14It can hold personalities as diverse
17:17as Martin Luther King and Genghis Khan.
17:21It even knows what it is.
17:24It's self-aware.
17:27We think it has a soul.
17:30But where does that soul come from?
17:33Is consciousness a product of the brain,
17:36and can it outlive the brain?
17:40Studying what happens to the human brain
17:43when people die is not easy.
17:46Death rarely comes on cue.
17:49But one aspect of death comes to all of us every day.
17:52Each night when we fall asleep,
17:55our consciousness switches.
17:58Our consciousness slips away.
18:04Professor Giulio Tononi of the University of Wisconsin
18:07is studying how our brains change
18:10when they lose consciousness.
18:13And in doing so, he's hoping to unravel
18:16the secret of what makes us, us.
18:19The simplest definition of consciousness is that
18:22which goes away when you fall into dreamless sleep.
18:25The problem, however, is the brain doesn't shut off at all.
18:28The neurons, the nerve cells, are actually just as active,
18:31in essence, as they are when you are awake.
18:34So it is an interesting scientific question.
18:37How would it be, then, that you disappear
18:40while your brain is still there and buzzing along?
18:43Tononi believes our level of awareness is determined
18:46by how much information the different parts of our brain
18:49share with each other.
18:52And this, in turn, will generate highly complex patterns
18:55in the brain, creating unique shapes
18:58that Tononi believes can be measured.
19:01Every experience is essentially like an extraordinary shape.
19:04Just like a fire with wonderful flames
19:07is an extraordinary shape that changes all the time.
19:10Now, it's a shape which is characterized
19:13by something I would call informational relationships.
19:16But it is a shape that shines of inner light.
19:19The fire of consciousness is a very special fire
19:22that's generated inside the brain.
19:25And it requires a very special set of ingredients
19:28in order to be able to burn and shine.
19:31But understanding when that fire is lit
19:34and when it is extinguished is far more difficult
19:37than simply reading a brain scan.
19:40So Giulio Tononi built an entire lab
19:43dedicated to the unconscious netherworld of dreamless sleep.
19:46And he designed an experiment
19:49to detect how the brain changes when we lose consciousness.
19:52It's the neurological equivalent
19:55of knocking at the door of a darkened house
19:58to find out whether anyone is home.
20:01We use something called transcranial magnetic stimulation,
20:04which is a way to inject a little current in the brain
20:07without having to open it up,
20:10so in a perfectly innocuous way,
20:13and then see how our cerebral cortex reacts to it.
20:16First, the team runs the experiment
20:19on the volunteer who's awake.
20:22A mesh of electrodes will keep track of all activity in his brain.
20:25Now a small magnetic coil is placed on his head.
20:28At the flip of a switch,
20:31it delivers a pulse of magnetism
20:34lasting a tenth of a second to his cerebral cortex.
20:37The burst causes neurons
20:40in a small patch of the brain to fire,
20:43and they in turn send signals to other neurons,
20:46making them fire as well.
20:49This complex pattern of neural activity
20:52spreads out to cover about a third of the cortex
20:55and lasts for almost one-third of a second.
20:58The conscious brain reverberates like a ringing bell.
21:02Someone is definitely home.
21:05But what happens when he's unconscious?
21:09Now that Brady is asleep,
21:12we are going to ring the bell again
21:15and see how his brain responds after falling asleep.
21:21Once again, the brain lights up,
21:24but this time there is no reverberation.
21:27The ring of the bell dies as quickly
21:30as the pulse of magnetism shuts off.
21:33The sleeping brain may be active,
21:36but it lacks the ability to share information
21:39between one part of the brain and another.
21:42Tononi believes this spreading of information
21:45is the key ingredient of consciousness.
21:48The waking brain keeps specialized areas
21:51in constant conversation,
21:54like a cabinet meeting
21:57with the Secretary of State, Treasury, and Defense
22:00all deciding on a unified plan of action.
22:03The meeting adjourns.
22:06The specialists leave, and nothing gets decided.
22:09Why do you lose consciousness
22:12when you are in deep sleep early in the night?
22:15The specialists that normally do talk to each other
22:18when you are awake, they stop doing so.
22:21There are some mechanisms that come into place when you sleep
22:24that makes the interactions between the specialists difficult.
22:27And in the end, it looks like they can't talk to each other anymore.
22:30When you lose consciousness, you're not there anymore.
22:33Tononi's ability to tell the difference
22:36between a brain that's conscious and one that's not
22:39may soon find application in a medical setting,
22:42assessing the level of awareness of coma patients.
22:45One of the first things you would want to know is,
22:48is anybody home?
22:51If that somebody is your wife or your son or your mother,
22:54and you see the eyes are open,
22:57and you don't know whether somebody is there,
23:00maybe even suffering, how do you go about that?
23:03Giulio Tononi has found a way to see consciousness
23:06in the human brain.
23:09But exactly how it arises amid the complex web of neurons,
23:12that remains a mystery
23:15at which he can only begin to guess.
23:18When one says that consciousness
23:21requires a complex system to support it,
23:25in some sense that must be true.
23:28But the Internet is certainly very complex.
23:31Another example, you could also say that
23:34a chess-playing program is very complex.
23:37So there are many things that people intuitively call complex,
23:40but only a few of them seem to be able to give rise to consciousness.
23:43So what you need is the right kind of complexity.
23:46And only a few structures, as far as I can tell,
23:49can do that, can pull out that extraordinary feature.
23:53Our cortex, the cerebral cortex, seems to be wired up
23:56almost ideally to achieve exactly that.
24:04But is there a way to discover the root of consciousness?
24:07And is this sense of self-awareness
24:10the same as the soul?
24:13This man thinks he's found the human soul
24:16and knows what happens to it when we die.
24:23What is the soul?
24:28Is it a field of energy?
24:31Is it something tangible?
24:34Does it have weight?
24:37In 1907, Dr. Duncan MacDougall
24:40determined that the soul weighs about
24:433 quarters of an ounce, or 21 grams.
24:46He determined this by weighing
24:49the bodies of dying TB patients.
24:52But in the 100 years since then,
24:55no one has been able to replicate his findings
24:58because that doesn't seem to be
25:01anything to weigh.
25:08Could there be some elusive substance
25:11that makes you you?
25:14At the smallest levels of existence,
25:17atoms are made of atoms.
25:20Earth has been recycling atoms for billions of years.
25:23Carbon moves from trees to oceans
25:26to the cells in our bodies.
25:29Even the atoms of dead people get reused.
25:34This means that an atom in your thigh bone
25:37might have been part of Cleopatra's lower lip.
25:40And this recycling doesn't just happen
25:43at the atomic level.
25:46You are constantly rebuilding yourself
25:49at the cellular level.
25:52Your body produces 1 billion new cells every hour.
25:55No matter how old you are,
25:58most of you is no more than 10 years old.
26:01Christoph Koch is a professor of biology
26:04and engineering at Caltech.
26:07He believes that what makes you you
26:10has nothing to do with individual atoms or cells.
26:13He believes that you emerges
26:16from the unique way the cells in your brain are organized.
26:19The brain is the most complex piece of matter
26:22we know in the universe.
26:25The human brain typically is on the order
26:28of 100 billion nerve cells.
26:31Each of those is a very complicated entity by itself.
26:34It's more like a little computer
26:37interconnected to 10,000 to 100,000 other nerve cells.
26:40Most neurons aren't conscious.
26:43But when they interact with each other on a massive scale,
26:46the result is a self-aware network.
26:49We believe that consciousness emerges
26:52out of the firing of millions or possibly billions of neurons.
26:55So that's what my soul is.
26:58That's what my feelings, my subjective feelings
27:01of pain and pleasure and of yearning are.
27:04But if, as Koch believes, who we are
27:07is a fragile and ever-changing network of brain cells,
27:10then there can be no eternal you.
27:13We constantly change. With each experience, we change a little bit.
27:16With some experience, we change more,
27:19and with other experience, we change less.
27:22To that sense, there's no constant.
27:25And as we age, again, my mind, my body,
27:28but also my personality and my mind changes.
27:31To that sense, there's no constant personality.
27:34It's a network of the brain and by the brain.
27:37This view of the brain is called materialism,
27:40and Koch is its champion.
27:43For materialists, the soul is nothing more than a fleeting illusion,
27:46an illusion that cannot outlive
27:49the physical network from which it arises.
27:55Once that electrical traffic ceases,
27:58because the brain itself doesn't work anymore
28:01and there's no more firing,
28:04then also the soul will cease to exist.
28:09But renowned cognitive scientist Douglas Hofstadter
28:12is not so quick to dismiss the possibility of life after death.
28:15He believes the soul does not disappear the moment we die.
28:20When I was a graduate student in physics,
28:23I had a professor who I was very fond of
28:26who was a religious person,
28:30and he believed, to my shock and surprise and confusion,
28:36that inside the brain there were certain kinds of particles
28:41that we hadn't yet discovered
28:44that gave rise to soul and consciousness.
28:47Hofstadter took a more scientific approach to the brain.
28:50He became a pioneer in modelling complex mental processes.
28:54He thinks about how people think.
28:57And what humans do best, in his opinion,
29:00is make mental maps of the world around them.
29:04The process of perceiving the world
29:07gives rise to internal representations of everything.
29:11If I look at this pepper shaker,
29:14I have an internal model of it.
29:17And I don't need to look at it because I've seen it so many times.
29:20I have an internal model of it that is stable.
29:23All animals make mental maps.
29:26The bigger the animal, the more complex the map.
29:29A bee knows the position of the sun and its hive.
29:33A manta ray learns to navigate the convoluted web of ocean currents.
29:39A baboon must keep track of the troop's social pecking order.
29:44Our maps are built from a lifetime of objects and people we've encountered.
29:48And one other crucial element.
29:52We incorporate not only the rest of the world,
29:56but we incorporate our own understanding of who we are and what we are,
30:00which includes superficial physical things,
30:04like the fact that we have two hands and five fingers on each hand,
30:08what kind of sense of humour we have,
30:12whether we're good at throwing free throws in basketball or hook shots.
30:16And we create mental maps of the world.
30:19And we create a concept that reflects who we are.
30:25Hofstadter regards this map of the world
30:29that also includes the map of the mapmaker as a mental feedback loop.
30:34You point a television camera at a television screen
30:38and then the screen gets put onto itself, etc., etc.,
30:42and you get a very complex visual pattern.
30:46The system itself is perceiving itself.
30:49The soul is an emergent process, an emergent entity
30:53that comes out of decades of perception and feedback.
31:00But this view of consciousness has a shocking implication.
31:04If the soul is just a strange mental feedback loop,
31:08then it should not be unique to humans.
31:11Any sufficiently smart network should be able to experience it,
31:15whatever it is made of.
31:17Which is why this latter-day Frankenstein is planning to build a soul.
31:22What he learns could point the way to a life beyond death.
31:29Religion tells us that our souls transcend the body.
31:35These are just shells that we walk around in for a while.
31:41Most scientists don't believe that.
31:44They say that what we call the soul
31:47is a self-aware network of brain connections
31:50that evolved over millions of years.
31:54If that's true, then what would happen
31:58if we built a copy of the human brain?
32:01Would it have a soul?
32:04We're on the verge of finding out.
32:07And if the mystery of the mind is something we can crack computationally,
32:12it could even give us an escape route from death.
32:20Around the world, teams of researchers
32:24are attempting to reverse-engineer a human brain.
32:28It's a tough job, because for all our research,
32:32the brain is still the most complicated instrument in the known universe.
32:37But mapping the brain could take decades to complete,
32:41and some rebel scientists have decided to harness the firepower
32:45inside living brain cells.
32:48They're trying to crack the secrets of the soul
32:51by fusing biology and technology,
32:55taking bits of brain and mating them to bits of hardware.
32:59Most computer simulations
33:02are limited to very simplistic neurons.
33:06What we have here in our culture dishes,
33:08with real, live, wet, squishy neurons with all their complexity,
33:13is immensely much more complicated
33:16than anything we can simulate on today's computers.
33:19Professor Steve Potter of the Georgia Institute of Technology
33:23designs and builds the brains,
33:26brains that are half living, half machine.
33:30Potter's team takes neurons cultured from rat embryos,
33:34then grows them on miniature plates of electrodes.
33:38This is the electrode array culture dish.
33:41You can see some fluorescently labeled neurons growing on it.
33:44These are the electrodes,
33:47with leads heading off to the electronics
33:50that we use to record from and stimulate the cells.
33:53These are all the axons and dendrites
33:56that represent the connections between the cells.
33:59Those connections form
34:02over the course of the first four hours in culture.
34:05You can see, in this time lapse here, connections forming.
34:08So those are the synaptic connections
34:11by which the neurons talk to each other,
34:14and we can film that conversation in progress
34:17using a calcium-sensitive dye here.
34:20So here you can see the cells flashing.
34:23Every time the cell sends a signal to another cell,
34:26it has a little burst of calcium.
34:29When the brain has grown,
34:32Potter sends information to it through the electrodes
34:35and the brain responds.
34:38That's wired up to a robot body,
34:41resulting in a new form of life.
34:44This is a hybrot,
34:47a robot controlled by living brain tissue.
34:50Its brains are in a refrigerator,
34:53but you can see its neurons react on the computer screen
34:56as its body finds its way around the lab bench.
34:59Like any animal,
35:02the hybrot has experiences and learns from them.
35:05In this case, how to navigate its environment.
35:08So the question is,
35:11could a hybrot ever become conscious?
35:16Whether or not we could ever get to
35:19conscious cultured networks is a question
35:22which I would say we've already answered yes.
35:25We have culture dishes that are receiving inputs from the environment.
35:28They're responding to them in complicated ways.
35:31So they're conscious of their environment
35:34in some very rudimentary fashion,
35:36but we could get to connections between different brain tissues
35:39and between the computer and the brain tissues.
35:42We could get to something that people would say is a high-level cognition,
35:45more like human consciousness.
35:48But if one day a hybrot or a computer wakes up
35:51and realizes what and who it is,
35:54if a soul emerges from those wires,
35:57how would we know?
36:00We'll have to rely on conversation.
36:03If we ask the artificial brain,
36:06if it tells us that it is,
36:09we'll just have to take its word.
36:12But the same thing applies when we talk to other humans.
36:15We don't actually know that other people are conscious.
36:18They might just be zombies who are saying the right thing,
36:21but having no private, subjective experience.
36:24I can put some sort of artificial intelligence
36:27into a computer right now
36:30that represents the kind of decisions I might make
36:33and has, in some sense, some of my consciousness in it.
36:36It's hard to do, but to get something that we would say
36:39is a good enough copy of my consciousness
36:42that if it were put back in somebody else's body,
36:45people would be fooled into thinking it was me.
36:48This is something we haven't even had a first clue of how to do it
36:51in any kind of a detailed way.
36:54Building artificial homes for our souls
36:57may be a long time coming.
37:00So what do we do in the meantime?
37:03Turns out the ideal vessels to carry souls
37:06may already exist.
37:09One could be sitting right next to you.
37:16Despite our advanced technology,
37:19the riddle of life still seems a long way from being solved.
37:24Or is it?
37:28In Bloomington, Indiana,
37:31Douglas Hofstadter says it's all a matter of perspective.
37:36He believes consciousness is the inevitable result
37:39of the strange and wonderful way the brain joins information together
37:43into patterns of thought.
37:46And the patterns of thought that form us
37:49are not unique to us.
37:52We are all curious collages of everyone
37:55we've ever been influenced by,
37:58living or dead.
38:01The pattern of your soul is the strongest and most complex
38:03in your own brain,
38:06but it can be passed on to other brains.
38:11This is a book of Chopin etudes.
38:14These black splotches on white paper
38:18capture some very, very central pieces
38:22of Chopin's emotionality.
38:25His highs, his lows,
38:28his sense of triumph,
38:30his sense of resignation or anguish.
38:34Anything that was part of his emotional makeup comes through,
38:38and one gets a very deep glimpse of another human being.
38:41Perhaps 150, 160 years after that person
38:45has officially vanished from the surface of the earth,
38:48something of their soul persists and invades
38:51the minds and brains of millions of other people.
38:55This is a form of life after death
38:58that we all experience,
39:01though we may not recognize it for what it is.
39:05It took a great personal tragedy
39:08for Hofstetter to see this,
39:11the death of his wife, Carol.
39:14We were in Italy,
39:17and it was a very sudden discovery of a brain tumor,
39:21and we only found out that she had a brain tumor
39:24on the 11th of December,
39:26and on the 12th of December in the evening
39:29she fell into a coma.
39:32So it was very, very, very fast.
39:36When somebody that I had been entangled with for so long
39:40and so deeply suddenly poofed out of existence,
39:43I then had to confront the question of
39:47what, if anything, survived,
39:50and where, if at all,
39:52can a human soul be transplanted,
39:57uprooted from one brain to another brain?
40:00And my answer would have to be
40:05in a very limited sense, yes.
40:09The degree to which Carol exists inside me,
40:12it's a much stripped-down version of her.
40:17It's a crude version. It's coarse-grained.
40:19It's as if one had a mosaic done in very, very small,
40:24fine stones, a million of them,
40:28and then it was destroyed,
40:31but somebody before it was destroyed had made a copy of it,
40:34but only using a thousand stones.
40:37And so the thousand stones still have the same colors
40:40and the same kind of arrangement, but much more coarse-grained,
40:43in a different medium, different stones.
40:46The original has been destroyed,
40:47but the copy exists in a coarse-grained version.
40:53And so we live on.
40:56A piece of our soul survives in everyone we have ever encountered.
41:01That soul fragment is the strongest,
41:04most recognizable in the people who loved us.
41:08This form of life after death is one we can all relate to,
41:12whatever our religion.
41:13But is there some other resting place for the soul?
41:16Does our consciousness just shimmer out of existence
41:19in our last moments on Earth?
41:22Is the soul nothing more than a network of neural processes,
41:26something that one day can be recreated in a machine?
41:29Or does the quantum state of our brain
41:32get reabsorbed into the universe at large?
41:36Scientists believe they are finally getting close
41:39to solving this puzzle,
41:40even though they passionately disagree about the answer.
41:44When you lose consciousness, you lose your soul,
41:47you lose everything.
41:49The world does not exist anymore for you.
41:51Your friends don't exist anymore.
41:53You don't exist. Everything is lost.
41:55If you take these near-death experiences at face value,
41:58then they suggest that the mind or the consciousness
42:02seems to function without the physical body.
42:06I think the quantum approach to consciousness
42:08can, in principle, explain why we're here
42:12and what our purpose is,
42:14and also the possibility of life after death
42:17and reincarnation and the persistence of consciousness
42:20after our bodies give up.
42:22I have great belief and knowledge
42:27that there is a wonderful existence for our souls
42:31outside of this earthly realm,
42:34and that is our true reality.
42:36And we all find that out when we leave this earth.
42:41Ultimately, every one of us will discover the truth.
42:45But will we ever enter our final hour knowing our fate?
42:52Perhaps some things really are too big for humans to grasp.
42:56That's when we have to shift from what we know
43:00to what we believe.
43:06Transcription by ESO. Translation by —