Unlocking the Mysteries of our Brain | David Eagleman (Transcript)

[00:00:00] Chris Anderson:
Hello there. This is Chris Anderson, welcoming you to The TED Interview. Now then, uh, this is a, a special episode that was recorded live at the TED Conference featuring one of the most amazing minds there is out there: David Eagleman. I mean, I introduce him from the TED stage, so I'm not gonna tell you all about him here, but, um, the way that he thinks about the human brain is incredible.

And, um, let's face it, we all care about our brains. So I think, I think you're in for an absolute treat of a conversation. Um, I talked to him for a while. The audience has extraordinary questions. Now, as you'll hear, this is the last official interview I'll be doing on The TED Interview, and that's because there is an amazing new host taking over.
I'm so excited about him. I know you will be too. He will be kicking off a new series starting in, in June. Um, he's actually in the audience at TED, and um, I make reference to him. But meanwhile, stay with us for an incredible conversation with David Eagleman.

[BREAK]

Okay. Okay. Okay. Hello. Hello everyone. This theater is so intimate and beautiful and it's lovely to see your faces. Uh, we are in for an absolute treat today, not just because you are, you are witnessing what will probably be the last, uh, TED interview done by me for a while. I'm, I am with great, uh, excitement handing over this role to someone who I'm a huge fan of: the author Steve Johnson. Steven Johnson, who's spoken at TED many times. He has a mind absolutely bursting with a curiosity. Actually, are you here, Steve, by any chance? Ah, here's Steve. Right here.

Um, so, um, we're soulmates, so this is, this is good. But I, I'm so excited to get to do this last one because we're really gonna get a chance to connect with one of the world's most amazing minds. Um, I mean, he's a Stanford neuroscientist, but he has somehow found the language and the ideas to make the brain and its possibilities come alive in a way that I don't think anyone else has been able to do.

I mean, as you know, he's written lots of books. There was a book several years ago called Some, which was a series of short stories, just about possibility. Um, in addition to being a neuroscientist, he's a possibilian and we'll, we'll talk about what that is later on in the interview. But then there's a book called Live Wired, which is, uh, really, it's, it's, it's, it's a revolutionary way of thinking about the brain.

That is, that is incredibly exciting and, and again, leads to many revelatory possibilities. He's got a PBS series called The Brain, a multipart. Um, he spoke at TED in 2015, a totally memorable talk. And, um, so anyway, we're gonna go on an amazing journey together. Please welcome David Eagleman.

[00:03:21] David Eagleman:
Great, thanks. such a pleasure, Chris. Thanks for having me.

[00:03:25] Chris Anderson:
So, the task I am setting you is to help us understand the miracle that happens in the brain. This couple pounds of squishy stuff locked in a skull that despite all that, somehow manages to create every single thing that we actually care about. It's a miracle, right?

[00:03:45] David Eagleman:
Yeah. I would say.

[00:03:48] Chris Anderson:
So, in your talk in 2015, you spoke about this model of the brain that you called Mr. Potato Head, and I'd like you to recap that model. ‘Cause I think it really paves the way nicely for what's to come.

[00:04:00] David Eagleman:
Yeah. Something I've always been interested in is the brain is locked in silence and darkness inside the skull and all that you have in there are spikes. These electric, you know, electrical spikes that release chemicals. And if I were to show you a part of the brain with some magical microscope where you could see all these spikes, and I said, “Hey Chris, is that the visual part of the brain or auditory or touch?” You couldn't tell me. I couldn't tell you ‘cause it's all the same.

It looks the same everywhere in the brain. And so the part that got me interested is, yeah, how does the system create the colors and the, the light and the smells and the touch and all that stuff, um, given that it's really just zeros and ones going on in there? So anyway, I got interested in the senses and the, the model I ended up proposing is this potato head model, which is that it doesn't matter how you get information in there, the brain will figure out what to do with it.

‘Cause that's what's really good at doing, essentially it's a all-purpose compute device, and whatever spikes it's getting, it says, “Oh, that's relevant for my behavior. I can do something with that.” And so the potato head model is simply that you can switch the things around and maybe even build completely new senses and plug 'em in anywhere and it doesn't matter.

[00:05:10] Chris Anderson:
So what, we'll come onto that part a bit more, but let's start, first of all, thinking about someone with all five senses. If it is five, uh, basically working, kind of, quote as “normal”. Um, talk a bit about this miracle of how this, this brain in the dark of, of a baby sort of developing you, you've got this blizzard of it incoming, just electrical signals, and yet somehow after a year or two, they are interpreted as “There is a face that I love and light up to. And if I say, ‘Mama’, something smiles. And if I say ‘wah’ what water comes or milk comes.” Or, so like how, how are those pieces possibly put together?

[00:05:54] David Eagleman:
Yeah. Well, okay. So as far as you know, this debate about nature and nurture? Totally dead question nowadays because it's always both.
So baby drops into the world knowing a lot of things already. Like how to mimic a facial expression. You know, you can stick out your tongue at a baby and the baby will do the same stuff like that. So, which is actually very complex visual-motor task to do. So there's some amount of pre-programming, but the interesting part is all the stuff that we absorb from there.

And so the trick that Mother Nature discovered is to drop us into the world with a half-baked brain and then we, you know, absorb the world around us such that, you know, an alligator born today is just the same as an alligator born a hundred thousand years ago.

But we drop into the world, by the time we're, you know, five, six years old, we’ve absorbed essentially everything humans have done before us. Our language, our culture, our family tradition, our nation's traditions, and so on. And we get to springboard off the top of that, and that just made us such a runaway species, we’ve taken over every corner of the planet as a result of not having to learn, you know, not having to play the role of a human over and over again, but constantly ratcheting up in what we're doing.

[00:07:02] Chris Anderson:
So this, this process of understanding, it seems to be built, I mean, at some point, right? Right. At the base level, it starts presumably because there are real things out there in the world. So, so say there's a puppy in the house, somehow the baby learns that, the same thing that sends at the same time that you get certain visual sensations you might hear “Yap, yap, yap.” And, um, and you might have the sort of the lick of puppy tongue on your face or something like that. And so the brain says, “These must be associated.” And then from that, a further understanding comes up. Is that about what happens?

[00:07:36] David Eagleman:
That’s exactly right. And, and the interesting part is that fundamentally the brain is multisensory, which means it's trying to make links across the senses. So you just got these little windows on the world, right? I'm just picking up a little slice of electromagnetic radiation here and some air compression waves here and other. And so what my brain's trying to do is put together, “Ah, there's an object that is a collection of these things altogether.”

Um, now the interesting part is when you're born, you don't know how to use your eyes or your ears, anything like that. And so it, it is a learned thing, but somehow when you learn it enough, it just becomes a qualia. You have a direct subjective experience of it.

[00:08:13] Chris Anderson:
So you, qualia is the subjective feeling of something.

[00:08:16] David Eagleman:
Exactly. So when you see the puppy, you don't think, “Hey, there's a bunch of photons that happen to be in the shape that I've seen before. And there's, you know, some medium frequencies hitting my eardrum that's probably a bark, and so on.” You just feel like, “Oh, there's the puppy making noise,” and such. Now the weird part is how do, how do qualia come about? How is it that information—which, you know, we can build a, uh, you can build a computer to recognize a puppy, but presumably it doesn't experience the puppiness and the love about the puppy and so on.

[00:08:45] Chris Anderson:
Yeah. Well, you're talking here about consciousness, so that's what I—we might come back to that. That's, that's a very, very hard one. But to go back to the Mr. Potato Head thing, so some of where this has come from is that you've observed that people who are lacking one sense, so say they, they are deaf or blind, their brain is, is able to repurpose the area that would have been used for, say the missing visual field and do something else with it. Talk a bit more about that.

[00:09:14] David Eagleman:
Exactly. You know, it's funny because I feel like that's something that neuroscience knows, but it's always considered sort of a side, uh, property of the brain. But to my mind, that's the most important thing or examples like that, because what it demonstrates is that although we have this textbook model of the brain—like here's visual system and here's hearing and touch and so on—that’s just how it usually turns out. But, exactly as you said, if somebody goes deaf, that part of the brain is taken over. Someone goes blind, that part of the brain is taken over. It's a very fluid system.

[00:09:44] Chris Anderson:
So one of the things you've observed and seen is that if someone is born deaf, for example, um, if you give them alternative access to audio information, not through their ears, but for example, on that wristband you're wearing, right, right there. Um, that they can actually start hearing through their wrist.

[00:10:07] David Eagleman:
Exactly. So this is, as you know, what I spoke about in, in 2015. Here. And, um, at the time I had made a vest in my lab, which had vibratory motors on it. We would capture sound and translate into patterns, vibration on the skin.

And people who are deaf could come to understand the world that way. And what we've done in the interim is, you know, we've shrunk it down to this little, to this little wristband. It has vibratory motors on the inside. Essentially we're taking the inner ear and we're just putting it on the skin. And so the audio information is captured, goes up your arm, up your spinal cord into your brain.

And because it's informationally relevant for a deaf person, you know, they see the dog's mouth doing this. They feel other thing, and they figure out how to make those associations. ‘Cause that's what the brain's always trying to do is make these links across the census.

[00:10:51] Chris Anderson:
What's, what's the experience? Do people feel that they're hearing it through their wrist or through the vest? Or, or, or what?

[00:10:56] David Eagleman:
So this is the crazy part. People on day one, they say, “Oh, I'm feeling this fuzzy”, you know. And, and we, we test them on these performance tests, and they get better and better each day. But by about four to six months into it, it becomes qualia. By which, I mean, if I say, “Okay, look, when the dog barks, what is the experience for it? Do you feel like, Oh, I felt something on my wrist?” And, and they say, “No, I just hear the dog bark,” right? In the same way that when I'm speaking, you don't think, “Oh, Eagleman is using some medium and some low and some high frequencies right now.” You just think, “Oh, I'm hearing his mellifluous voice.”

[00:11:28] Chris Anderson:
Right. I don't, I don't hear your voice here. I hear it right there where it is.

[00:11:31] David Eagleman:
Exactly, exactly. You projected out here, even though it's all happening inside there, you think I'm out here, and you're just hearing sort of the, the high level voiceness of it rather than the frequencies. Yeah.

[00:11:42] Chris Anderson:
So in a way that that is the only way for the brain to efficiently make sense of it, is to place all these things together into this sort of what, what, what we say at any rate is a 3D space out there with these different objects, all of which have different things associated with them.

And, and, and then everything else becomes unconscious. They are just, they are out there. And we notice if something dramatic happens, but we just assume that the world is what it is.

[00:12:04] David Eagleman:
That’s exactly right. So consciousness is something like an operating system that continually abstracts and makes higher and higher level things. So I can say like, “Oh, there's Chris.” I don't think, “Oh, there's 30 trillion cells that are all hanging together in the shape of Chris.” I just, oh yeah, there he is. Yeah.

[00:12:17] Chris Anderson:
Now, so in your talk. You pointed out that other animals, um, other than us have very different senses that some of them can see a much, a different slice of the electromagnetic spectrum than we can. For example, just talk, talk a bit about that.

[00:12:32] David Eagleman:
I, I've always been obsessed with this, so, you know, the part of the electromagnetic spectrum that we detect, we call that visible light? You know, radio waves, x-rays, microwaves, gamma ray, all this stuff is light, just of different frequencies.

We're just, um, we come to the table with biological programming to see a particular thing that's useful for the big ball of fire in the sky and what it illuminates. So, but yeah, lots of animals see in the ultraviolet range, the infrared range, uh, obviously. With sound, you know, many animals are up in the ultrasonic frequency, having whole conversations that we're not picking up on.

And, and what, what I've been sort of compiling lately is examples of animal species that are doing things where, for example, you know, this animal, the little brown bat is up in this frequency and the canary is down this frequency, and so they don't even hear each other anyway. It's just, there's all kinds of communication going on around us that we have no access to.

[00:13:23] Chris Anderson:
So it's, it's, it's like each species has, has extracted a tiny fraction of the total amount of information that is actually out there at any time. There's an unbelievable amount of electronic activity in, in the world. We, we pick a tiny slice of it that we have found to be useful to navigate and survive.

[00:13:42] David Eagleman:
Exactly right. And by the way, it's often a Darwinian issue too, like where is no one else doing it? For example, the frogs that move close to rivers that make a lot of noise, they end up, uh, as a species shifting their frequency that they communicate to a much higher frequency that, uh, takes care of the babbling brooks. So they don't have to be distracted by that. So yes, there's lots of reasons why we end up exactly where we do.

[00:14:04] Chris Anderson:
So, that means that there is a possibility that we could consider, which is what happens if we plugged into our brain, sensors that provide different levels of data. And you, you had quite a broad range of speculation there about what we might do from, you know, you, you could have like an air controller could have flight patterns or something like viscerally, like wired into them

Or, um an, an investor, like a currency trade, or whatever, could have a vest with that, that connected certain trends and this is happening in Hong Kong or whatever. You know, they would somehow come to learn to make an instinctual “Oh my god, sell.” Um, I mean that, if you could pull that off, that would probably make you a fortune.

And, and also really annoying, um, maybe not. Right, but what, what's worked since, since that talk? What have you looked at that is showing signs of actually a Mr. Potato Head new sense that might actually work.

[00:15:03] David Eagleman:
Yeah. So, so we have different projects going on, um, that, you know, things that we're trying with, with the wristband.

One of the experiments we've done, I think there was post-TED Talk was, um, with people who were blind. Uh, we took 'em to a place where there was lidar set up in the offices and so, By tapping into that stream, we could know where they were and where everyone was around them. So let's say I'm blind, I could feel you. Oh, there's someone on my left. And as you get closer, I feel it more intensely and farther. And if you go behind me, I can feel you moving around on my skin the whole time.

And it turns out, the interesting part is there was zero learning curve there. People got it immediately because there's something about 3D spatial structure that is just obvious to humans. And, and this is a product that we wanna launch. The only thing is, you know, we have to figure out something other than lidar, which is, uh, a pain.

[00:15:49] Chris Anderson:
But talk, talk, talk to Elon Musk about that. He's got the same problem. It's like, it's big and expensive, right?

[00:15:55] David Eagleman:
Yeah, exactly. Exactly. Yeah. Happily, there's so much going on with, with mapping from a phone for AR that we, we think we can just hook up the phone in somebody's chest and do it that way. So there's, there's so many applications that we're working on. I'll tell you one that, uh, I don't quite know the future of. But, um, so we hooked up a smartwatch, which measures your, you know, your heart rate, heart rate variability, got various skin responses, things like this.

And then we feed that data through the internet to the, to the wristband. But the key is I'm not listening to my own physiology. Let's say I'm listening to your. Or you're listening to your wife’s or something, right? So the point is, you're on the other side of the nation and you say, “Oh, you know, she seems stressed out. Hey honey, is everything okay?”

You see? Now I have no idea if this is good for marriages or not. It might be terrible. And so, but it's a really interesting thing to be tapped into.

[00:16:39] Chris Anderson:
Honey, you are sounding worryingly happy. [Laughter]

[00:16:46] David Eagleman:
Yeah. So, but, but there's, but, but you see, there's a whole space of possibilities to be explored here about what it is to be human and how to tap into someone else's feelings. This sort of thing.

[00:16:56] Chris Anderson:
Yeah, that's interesting. Uh, have you thought about possibilities of just increasing people's aesthetic experience of the world? I mean, in principle, if we can only see a tiny sliver of the electro-light spectrum, if you could open up a much bigger spectrum, what if you could let people—give people these extra senses? Do you think that at some point new qualia would open up and suddenly the world that we see now, you would just see a, you would see a million more colors and you would just be full of joy?

[00:17:20] David Eagleman:
Yeah. So I think one of the ways to get at this question is, for example, we know that some fraction of females have not just three types, but four types of color photoreceptors in their eyes. So they're seeing colors that the rest of us can't see. You know, they can discriminate colors, say, “Oh, that's different from that.”

But to us, it would look exactly the same. Okay, what's interesting is that they can't explain to you what they're seeing that's different because you've never experienced those other colors, and so you're stuck in your, umwelt, you know, the, the experience of the world that you have. In the same way that if you talk to someone who's colorblind, you can't explain what purpleness is, or red or something like that.

But the difficulty is getting you outside of your fence line of what you're able to perceive. You can see a certain number of colors and that's it. You can't see more of that. So I've been very interested in this question of how does the rainbow build qualia and how do you build new qualia?

So my hypothesis is, remember where we started about how it's all just spikes? My hypothesis, it’s about the structure of the data coming in. So your eardrums are picking up on a one-dimensional signal of, um, pressure changes. Um, you know, your nose is picking up on mixtures of molecules, things like that.

Okay. I think the structure of the data somehow determines the qualia because you would never confuse sight with sound. If I showed you something, you wouldn't say, “Oh, I just heard something.” Um, the reason I'm bringing this up is because as we feed new data in, we might be able to actually build new qualia where you have a new sense that's not hearing or touch or sight or smell, but it's another thing.

And what I think this means is this could sort of be like a speciation event for the human species where, where we start having very different experiences. Now, I just wanna emphasize this is a different degree of the same thing in the sense that we're already all having different experiences about things, but it may be that I, I, I can experience something that you can't in vice versa.

[00:19:12] Chris Anderson:
Right, right.

[00:19:12] David Eagleman:
So if I say we don't know what the limits would be, could I add a sixth sense? Yes. Could I have a seventh and eighth and ninth? Possibly. But the idea is could you create a brand new sense that is not describable by any of the others? And I think probably yes. And by the way, I think there's probably no limit on it.

[00:19:26] Chris Anderson:
So I'd love you now to go on and explain the model of the brain that you describe in Live Wired. Because I have to say, it blew my mind.

[00:19:36] David Eagleman:
Great. Thanks. I, um, one of the things that has been so interesting to me, and as I said, not something that's typically explored is, is the way that it's a very fluid system, and it's really predicated on competition: where the brain doesn't let any land lie fallow because the neurons are all competing in there to, to take over and, you know, and make sure that they're maximizing information. And without going into details, you know, one of the theories I proposed in there is that the brain is infotropic, which means it moves towards information sources, whatever is relevant to it, in the same way that a phototropic plant moves towards the light sources.

So the brain's actually re—you know, it's changing its territories based on what is maximally useful for interacting with the world.

[00:20:21] Chris Anderson:
So this was initially certainly quite shocking to me ‘cause I, I like to think, you know, our brains really matter to us. We think they're the most important things we have and you know, it's this miracle and our DNA creates this and it makes this whole beautiful structure that is so invaluable to us and, um, and does all this magic and, and you are saying that's actually the wrong way to think about it.

It's actually the brain is growing. All these neurons, like billions of them with their trillions of connections and actually they're, they're in competition with each other. And that the model is, it's like a forest. You're saying like the plants are all fighting with each other for the light. Brains are fighting, the neurons are fighting with each other for information. And so the first reaction to that is, “No, I don't want there to be this perpetual war going on in my brain.”

[00:21:10] David Eagleman:
But I, I think that's the best model to explain, uh, the data, right? So right. Exactly. The, the analogy of a forest is, is the right one, which is, you, you walk through a beautiful forest, it's also wonderful, but every plant in there is competing life or death to get to that, to get to those photons and, and only the winners survive. It's the same thing with neurons. You don't get new neurons, by the way.

You just have the neurons that are there, the 86 billion of them, and they are all fighting to be relevant. And what you see is that an individual neuron, it grows, it connects various places, you know, makes up 10,000 connections. But what it's doing is it's looking for where, where is something working here?

You know, the analogy I use is, is it's, you know, it's like somewhat at a bar, late at night, at closing time, trying to find a date with, you know, is this working? Is it re okay, It's not resonating? Go somewhere. Okay, no, that's not resonating. So, but the point is, neurons are constantly unplugging and replugging and trying to find where they fit.
And if a neuron doesn't fit anywhere, it actually commits suicide. It's called apoptosis. That's what neurons do. They kill themselves. But, and the death of cells is, is actually a super important part of how biology works.

[00:22:14] Chris Anderson:
So this helps make sense of this idea that, um, of the repurposing of senses, so if someone's born blind and the neurons that would've been connected to their retinas and getting nothing coming.

They, they start to fight for data elsewhere and can be repurposed by, um, what's coming in through your ears so that blind people have a much richer oral experience.

[00:22:40] David Eagleman:
That’s exactly right. And one of the big surprises to me, um, just over a decade ago in neuroscience, was coming to understand how fast these takeovers can happen.

So we're used to thinking about, okay, Fred was born blind. His visual cortex got taken over by these other things. But some colleagues of mine in Harvard did this study where they put people in the scanner, they blindfolded them tightly and they looked at their brain's responses to touch, things like that.

And what they found is after about 60 minutes, you were starting to see activation in the occipital lobe in the back of the head here, which we normally think of as visual cortex. You were seeing activation. So when I read that paper, I talked with my student and we talked about this all day, and we came up with an entirely new theory about why we dream at night.

[00:23:25] Chris Anderson:
Yeah. So talk about this.

[00:23:26] David Eagleman:
So what we realized is, you know, the visual system in particular has a real challenge to deal with, which is the rotation of the planet into darkness. So in the dark, you can still hear and smell and touch and so on, but you can't see. Obviously, I’m talking about our evolutionary history, not our electricity-blessed last microsecond of time. So it gets dark, you can't see. And so that puts the visual system at a disadvantage. And when I realized how rapidly takeover starts happening, I realized if you're a really plastic species like we are, boy, the visual system has gotta do something to defend its territory during the long hours of the night.

And that's when I realized that's what dreaming is. You. You have these very specialized circuits that just blast random activity into the visual system, the occipital lobe. And because we're visual creatures, you experience that as vision. Even though your eyes are closed, you're having a full rich visual experience.
But the whole point is just to defend the visual system against its neighbors.

[00:24:21] Chris Anderson:
I mean, you know, we have, we have millennia of people waxing lyrical about the mystery of dreams at looking to interpret them. There's numerous bible stories about them and, um, everyone has a theory of how their dream predicted something else and all the rest of it, and it's at one level, I mean, it's certainly amazing, but it's kind of disheartening to say, no, this is just a group of neurons in your brain desperate for some action in the night. And so they're just firing at random. Showing you shit.

[00:24:51] David Eagleman:
Yeah, exactly. What’s interesting though, um, I don't think dream content has any meaning, but it is of course, related to what you are thinking about during the day.

And so, because essentially those synapses are hot, so when you blast random activity in there, you know, you tend to see things, but of course, things aren't anchored in the same way. So it has something to do with the person you saw during the day, whatever. But it all, you know, drifts off quickly into other realms.

[00:25:10] Chris Anderson:
Just your visual cortex having a little workout.

[00:25:13] David Eagleman:
Exactly. So, so, so by the way, I just wanna mention one of the things, uh, my student I did then is we went. And studied very carefully 25 different species of primate and how plastic they are. ‘Cause you know, homo sapiens, we are the most flexible. And so then we correlate how much REM sleep.

They get rapid eye movements, which is, you know, the, the correlate of dreaming and, um, and, and it correlates perfectly, which is to say the more plastic species you are, the more hours you have to spend dreaming at nighttime to defend your visual system.

[00:25:41] Chris Anderson:
Wow. So the more you are, you have a brain that where the neurons are in competition and can go in any of different directions, that really correlates to how much you dream.

[BREAK]

So I'm, I was so struck reading this, like my first reaction to it was, “Oh God, competition.” You know, I'm, I'm feeling stressed by it. But then, you know the analogy with the forest that's in there, I mean, a forest is one of the most beautiful things there is. Right? So, so I'm wondering how much, this is almost like a, just a repeated pattern in nature that as things look to maximize whatever goal it is, they, they try out all this complexity, and the end result is, is something beautiful and amazing and, and so I'm taking the view, David, inspired by you. Actually, it's, it's the key to making it amazing.

[00:26:38] David Eagleman:
Oh, quite right, quite right. I mean, when you look at anything like a, like a city, um, yeah. The whole thing is about, okay, is this restaurant gonna make it on this block? Is my bookstore gonna be more attractive than a bookstore down the road? Is my bank gonna attract customers more than this bank over here? And so on?

The whole function of a city is all about this, um, competition. And it's a beautiful emergent property that we get out of it. And by the way, I always use, I I'm, I'm hooked on using the analogy of cities when we think about brains, because, you know, people always ask neuroscientists things like, “Hey, where in the brain is, you know, whatever, greed or, you know, capitalism or whatever?”

But, but the fact is everything is distributed. It would be like looking at a city and saying, “Okay, where's the economy of the city?” The answer is it's not in any spot. It's, it's all the action of the city. Collectively. You get this thing called the economy that comes out of that, and that's what everything interesting in the brain is, whether that's consciousness or the feeling of love or whatever. That's what it's about.

[00:27:35] Chris Anderson:
Yeah. That’s so interesting. I mean, another way of, of framing it to me that is both in a city and, and in the brain, uh, and in a forest is, is that it's not just competition. It's, it's an exploration of possibilities. Like so many things are, they're just looking for “Where can I go? What can I do to find what interests me?” and that the amazing emergent property from that is something magical like, in our case, consciousness.

[00:28:00] David Eagleman:
So that's exactly right. This is the fascinating part is that, so when you're born, when you're a baby, neurons don't have that many connections, and over the first two years of life, they're making massive connections. They start, you know, they make, they make so many that by the time you're about two years old, you've got about 20,000 connections per cell.

And from that point on, from about two years onward, it starts pruning. It's like an overgrown garden that prunes. But the way it's pruning has to do with the possibilities in your, what language you speak, what you know, what your culture, what your technology around you is, all that stuff. And so essentially it's like you're dropping this thing in the world, and it figures out, “Oh, how do I resonate in this world that I find myself in at this moment in time, in this place?”

[00:28:46] Chris Anderson:
So talk a bit about just that plasticity and, and the timeline on which it works.

[00:28:50] David Eagleman:
You're plastic your whole life, and so there have been all these studies on adult plasticity and it always comes as a surprise. To people that, “Oh, I didn't know you were, you were still plastics now.”

But the, the reason that adults tend to be sort of less plastic than children, I think generally has to do with motivation. What I mean by that: your job, your brain's job, is to make an internal model of the world.

Remember, your brain is in silence and darkness. It's trying to figure out: how do I operate in this world? How do people react when I say this? How do I get a job? How do I do this? Okay. Um, the, the key is, As you get older, you get better and better and say, “Okay, yeah, I get this world. I know how to operate in this world.” And as a result, you don't have that much motivation to change.

[00:29:32] Chris Anderson:
What, what advice would you give to someone who's, I don't know, in their forties, fifties, sixties, seventies, eighties? Like how. Yeah, how, what, what should we do to, to be the best stewards of our brains?

[00:29:43] David Eagleman:
I'll tell you, It's so easy. It's to seek novelty. It's to seek challenge. So the key is, for most people, as they get older, they, you know, whatever, they, their lives shrink, they watch Jerry Springer, they do whatever they're doing.

But the, but the, the key is challenge yourself. So there's this study that's been going for decades, you may know about this, called, um, the Religious Orders Study, where a whole bunch of nuns in convents volunteer to give their brains upon their death. So, what happened is, um, the researchers started examining these, you know, the histological samples and realized that some for, actually these nuns had Alzheimer's disease and their brains were physically getting chewed up with the Alzheimer's, and yet nobody knew it when they were alive.

They just weren't showing the cognitive deficits. Okay. This led to a big understanding that was going on was they lived in the convents till the day they died. They had social interaction, they had chores and responsibilities. They played games, they had conversations. They were doing all kinds of stuff. And as a result, even though their brain was physically degenerating, they were building new bridges, new roadways, and as a result, they were able to essentially fight back against the, the degeneration of the tissue. This is the important thing, is to always seek challenges. And by—go ahead.

[00:30:55] Chris Anderson:
I was gonna say, is it challenges that, that, um, themselves vary? So someone, if someone finds doing a crossword challenging, but they do it every day and keep doing it, is that good? Or is that actually, or playing bridge every week or something like that? Or is it actually much better to mix that up and actually, “Nope, I’m gonna travel to a new place and whatever.”

[00:31:15] David Eagleman:
As soon as you get good at the crossword puzzles, you gotta drop that and do something that's hard. The key is to be between the levels of frustrating but achievable. And, uh, and that's where you always want to keep yourself in life. And as long as you're there…

[00:31:28] Chris Anderson:
Um, if not between frustrating and achievable. You're always frustrated and never achieving, just to say.

[00:31:35] David Eagleman:
Yeah. Yeah. It's, it's, it's funny because there's so much stuff pouring outta neuroscience labs, but this is still this single piece of advice really, that we have for putting off dementia.

[00:31:46] Chris Anderson:
Let, let's talk about what could be coming, um, because, you know, we've heard at this conference, um, about, um, you know, brain-computer interfaces, um. Tom Oxley spoke about the possibility of sliding up through a blood vessel in your brain, a stent, and, and you know, putting an, a connection to the brain. Um, NeuroLink is out there, Elon Musk’s company. There are other attempts to imagine a world where we are much more hardwired to electronic data.

The logic of what you are saying is that, holy crap, all bets are off as to what that could mean because you are, you've got a forest of neurons. They're gonna go, “Hello, new data supply, let's go.” And, uh, and anything could grow into it. And then it, like, what, what are some possibilities for the future? Are these dreams of, for example, telepathic communication between humans, possibly the sharing of emotion directly? Is that a possibility in our future?

[00:32:40] David Eagleman:
It is a, it is a possibility, but it's, I think an open question which applications, if any, we’re really going to want. So all these things with, with brain-computer interfaces that are invasive are super useful for people. For example, who've lost control of their body, they're paralyzed, locked in syndrome, anything like that. Tremendously useful, um, because it allows them to express their bodies in the world.

But, do I want telepathy where you could know my thoughts? Or is it very useful that everything goes through a series of checkpoints before I say something out loud? Probably the latter. So I don't, I don't wanna have, you know, plus I'm not gonna get an open head surgery so I can text with my phone faster or something. It's not worth it. Uh, so will the everyday person get a brain-computer interface? I don't, I don't know.

[00:33:27] Chris Anderson:
Well, one reason why I'd consider it would be memory. Like, I'm, I'm tortured by the fact that I don't remember people. Well, I love them. I think they're amazing and I, I don't remember that. I'm ashamed of it.

And it's sort of like, it's hard. Um, it surely like, it, it's easy I think, to imagine a situation where if you had a brain-computer interface connected to, you know, your full list of friends and, and that there was visual recognition or whatever, like you, you could just get an instant spark on, “No. That's Brian walking up to you. Remember Brian? He gave you a present last year.”

[00:34:03] David Eagleman:
Um, that's right. I would say we're actually quite distant from this. So the idea of, for example, an artificial hippocampus, which is an area in your brain that's involved in laying down memories, um, for us to actually be able to understand, “Hey, how does the memory get written down? How do you write it down differently?”

And of course, the key is you're meant to forget most things in life. Memories beautify life, but only forgetting makes it bearable. And it turns out that most things, you don't wanna remember the number of cracks in the sidewalk or how many coffee cups were back in the green room, or what… all that stuff you want to, or where you parked your car two weeks ago. It doesn’t matter.

So, so if you had an artificial thing that said, “Okay, Chris, here's where you parked your car seven years ago.”

[00:34:48] Chris Anderson:
I still want an editor of some kind. I mean—

[00:34:50] David Eagleman:
Editor. Exactly.

[00:34:52] Chris Anderson:
Um hmm. Oh, I'm, I'm a little heartbroken, but I guess part of the problem is that science, science just hasn't yet figured out how memory even works. Like it's, it's, it's a really, it's not a simple problem at all to figure that out.

[00:35:04] David Eagleman:
Ah, that’s interesting. We've made, there's a lot of progress. But yeah, I would say, um, there are many mysteries still to how it works.

[00:35:10] Chris Anderson:
Um, I would like to turn to your role as the sort of founder, let's say, of possibilianism. Um, what the hell is that?

[00:35:23] David Eagleman:
Yeah. So one of the things that's been interesting to me, that you have to get to a certain age in science to come to understand or admit this, is that science is like a pier that we build out, uh, into the, into the unknown. It's only a certain length and beyond the length of what we know is all uncharted waters.

And in our lifetime we're only gonna build a few more slats on the pier. And so the reason I started this movement of possibilianism, this was, um, when you walk into the bookstore, there's really just two views on what's going on. So you've got the fundamentally religious that have a story where they say, “Look, you know, there's a guy on a cloud with a beard” and whatever. Very great detail.

And then on the far other end you have, you knows, say the neo-atheists who say, “Look at the extreme”, let's say. I don't mean to caricature it ‘cause it's very important, but yeah, they say, “Look, look, we've got this all figured out. F = ma. E = mc^2. We got the whole thing figured out. This is what science is about.” But we know too little to pretend that we've got everything figured out.

For example, the question you asked, how do you build consciousness out of pieces and parts? We don't know. Are there extraterrestrial civilizations? You know, certainly possible. Maybe probable, but we don't have any evidence about it one way or another. So somehow just like what's going on in the political sphere, these two sides have polarized each other.

And so scientists have been sort of forced into this position of acting like, “Hey, we've got this all figured out. Don't worry, I don't wanna hear any wacky thing ‘cause we got it all set.”

[00:36:50] Chris Anderson:
So, so what you're saying is that it's kind of crazy to limit your total worldview to two possibilities.

[00:36:57] David Eagleman:
Exactly.

[00:36:58] Chris Anderson:
The controlling God of the Bible, say, or you know, whatever your version of that controlling god is, who invented, who created everything or no god at all, or I don't know which of those, but those are your only choices, right?

[00:37:11] David Eagleman:
Exactly. So, so if you end up in the middle, um, a common term for that is agnostic, but typically agnosticism just means “I don't know if the guy with the beard on the cloud exists or doesn't exist.” That’s what most people mean by agnosticism. So I call myself a possibilian because the, the interesting thing to me is how do we understand the structure of the possibility space? And really that is the job of science is to figure out, okay, what are the possible hypotheses of what the heck's going on here? ‘Cause it's a very mysterious existence that we're sitting in. How do we use the tools of science to rule out whole parts of that?

[00:37:47] Chris Anderson:
So, so if one goes with that worldview, don't we miss out? Like one of the powers of religions has been that it's given people true sustenance and anchoring and, um, you know, comfort.

And are you confident that we're a species that can even handle a world of too much possibility where we're, we're sort of terrified enough as it is? Aren’t, isn't there a danger that we just freak ourselves out even more?

[00:38:12] David Eagleman:
It certainly seems to depend on personality type, but I think as we teach science, science becomes more of the mother's milk that we raise our children on, which is clearly what's happened in the last hundred years and will continue to be even more so.

Um, we can teach the scientific temperament, which is one of not saying, “I'm gonna commit and fight and die for a particular viewpoint”, but instead to say, “All right, I don't know. I'm gonna look at all the hypotheses arrayed in front of me. I'm gonna try to gather evidence to weigh in support of one over the other.” And, and it's an ongoing game. And I think if we can teach our children that we'll really get somewhere in terms of our legislation, our education, how we have warfare, all this sort of thing.

[00:38:56] Chris Anderson:
Very, very interesting. David Eagleman. So look, we, we've got, uh, an amazing audience here. Um, it's your turn to ask some questions. I think there are mics around.
So I think if you put up your hand, a mic will come to you and we'll just take, so try and, uh, just your name and then the question crisply as a, as a question. And let's see how many of these we can get in. Let's go. Who's first, who's got a mic? Speak.

[00:39:20] Audience Member:
My name’s Yonda. Uh, I'll ask the, uh, the hard question. Pun intended. Um, consciousness. Why? How is it useful? Is it necessary?

[00:39:28] David Eagleman:
Yeah. So the Great, Thank you so much. The question of consciousness for anyone who doesn't know is how do you put together cells? Lots of them, and there's very complicated thing, and you experience the taste of feta cheese or the redness of red or the pain of pain or things like that because we can program computers, do all kinds of great stuff, but it presumably doesn't experience anything the way that we do.

This is an unsolved question of neuroscience, and I think the largest one, and the weird part is we don't even know what a good theory of consciousness will look like because none of the tools that we use yield something like… I can't say, you know, “Do a double integral and carry the five and what, and then that equals the smell of cinnamon.”

Um, we don't know how to take the tools we have and build consciousness, so that's why it is called “the hard problem”. We're still, we're still stuck there. There are all kinds of good, I would say, proto-theories that are moving along about noting what's going on in the brain about, “Okay, you need a certain amount of integration and also differentiation of different states.” There are various good things like that, but it's not a, an explanation yet.

[00:40:36] Chris Anderson:
I… so this, this tortures me as well. And, and you know, the, the way that I've sometimes asked the riddle is to think about the most intense form of consciousness, which is pain. I mean, so much misery is caused by pain. Why dark artist God did you give us pain?

Um, the first answer is, Oh, but pain is so important, because without pain is how do you keep your body protected? When you, when something hurts, you know, if, if you put your hand in the fire, you put it out because it hurts. And so your hand is okay. So, of course you need pain. But you can build a robot with a heat sensor that if it feels heat, it, it withdraws its hand, the robot does not suffer. So it's, it's such a riddle of how, at what point when you complexify a network of electrical signals, something has to start feeling something.

[00:41:24] David Eagleman:
I, I, I hinted this earlier that it's, it's sort of like an operating system that has successive levels of ab—abstraction, and so it may be that the same way we have qualia, that pain is a way of just summarizing something so that you can use it as a building block for future things, where you say, “Oh, yeah, I, I had this experience and so you know, this is what I shouldn't do in the future.” This isn't an explanation, but it's pointing in the—in the right direction of something, which is we eventually start to experience things directly.

[00:41:53] Audience Member:
Hi, uh, this is Brian, and two, two things. I really like the, uh, you know, two-year-old, uh, growing and then pruning of, of neurons, and also like the idea that knowledge is built on top of, uh, sort of all of humanities information for that. Uh, talk a little bit about babies and their ability to use tablets to do anything they want, and also talk about why all of our kids are teaching us how to use technology these days.

[00:42:16] David Eagleman:
Yeah, Yeah. Okay. So the reason why they're teaching us, of course, is, they drop into a world where that's part of the background furniture and so they get it. It's easy to go. I happen to be super cyber-optimistic about this point, which is I think the next generation is guaranteed to be smarter than us, like significantly so.

So what we got growing up was a lot of just-in-case information, just in case you ever need to know, the Battle of Hastings was 1066, whatever. But what kids now have is tons of just-in-time information. So soon as they’re curious about something, they say, “Hey, Alexa, Blahba. Hey Google Home. You know, what's the answer to this? How do I do this?”

And they get the information in the context of their curiosity. The reason that matters is because when you're curious about something, that's the highest level of learning, and we now understand is because you have the right cocktail of neurotransmitters present when you're curious about something and you get the answer in the context of your curiosity. So I just think this is terrific um, what the next generation—

[00:43:13] Chris Anderson:
And does curiosity feed curiosity?

[00:43:15] David Eagleman:
Yeah, exactly. And we all know that experience of surfing through Wikipedia, and you end up somewhere and you think, “God, how did I get here? I started somewhere else entirely.” Yeah.

[00:43:23] Chris Anderson:
That process of surfing YouTube where you were, start off perfectly innocently and end up in some depraved pornographer's mind or something like that.

Anyway. In a minute I'd love to have a question for my soulmate here, Steve Johnson. Um, so if we can get a mic down here, but meanwhile, whoever's got the mic.

[00:43:41] Audience Member:
Oh, hi. Uh, my name's Martin. Uh, the question is, uh, I think one of your thorny problems, free will. Uh, if so, where, what, do we have it or do we not?

[00:43:51] David Eagleman:
Yeah, it's a great question. And the, the question is, you know, given that you've got these 86 billion neurons and certainly seems to be running, um, deterministically, you know, these neurons fire or doesn’t it, the question is where is there any room left for free will? So most neuroscientists… I would say think we probably don't have free will.

We're essentially like extraordinarily complicated meat robots that are moving from state to state based on the inputs. The only thing I would say is we have to have some intellectual humility about that answer because we don't know. We really don't know, and even though it's very difficult to explain where free will would come from, it’s also the case that we don't have explanation for a consciousness comes from, but you believe you have it. And so we understand that there's a mystery that we need to solve somehow.

Um, I advised for the television show Westworld, um, on this topic, and we had an eight-hour debate in the writer's room about free will and what we do know, what we don't know. And I think they did a, a really lovely job throughout the series of maintaining that middle road, that complexity, because with the, the hosts, the robots, um, you keep thinking, “Oh wait, they seem to have developed free will.” And then, and then you're not clear. And they, and they say some speech about how they have free will, and then the guy who writes the speech says it in concert with them indicating that that was a pre-written speech and so on. So anyway, they've left it just as complex as, as we have it.

[00:45:12] Chris Anderson:
I spent, um, three days lying on my floor as a Oxford philosophy student, trying to think about this question. My, my conclusion was that I didn't answer the question, but that the, when we ask, do we have free will? The real riddle is not that. It's who is the we that is asking the question.

[00:45:29] David Eagleman:
Oh, nice. Yeah. Yeah.

[00:45:29] Chris Anderson:
Um, but anyway. Steve, are you here?

[00:45:33] Audience Member:
Um, I’m not Steve, unfortunately. ‘Cause I would like to be your soulmate. I'm Noora. Nice to meet you. Hello. Um, I found your, your provocation that we might have six, seventh, eight senses wonderful. And so then I, my brain went to these things that we might think are metaphysical.

For example, when we experience empathy as opposed to sympathy, I could feel your pain. I'm embodying it. Right. But perhaps that's also a sense that also exists because there's all this information that I am downloading: your body behavior, your heat, your and that, that I'm absorbing. So would you say empathy is a sixth sense? Does it exist and why do only a few of us have it?

[00:46:13] David Eagleman:
Um, here's the thing. We are extraordinarily social creatures and so much of what's going on in your brain and my brain has to do with each other and with everybody around. Um, you have thousands of people stored in your head that you can make pretty sophisticated models of, and if I chose any two people from your phone directory and said, “Hey, does this person know this person?”

You'd probably have a pretty good model that, “Oh no, they've never met.” Or, “Oh yeah, they'd get along or whatever.” I mean, you've got so much of your brain's circuitry devoted to thinking about people and so on. So there's this funny sense in which you don't end at the borders of your body, but you… we're all part of a mega-organism in a sense.

And for the most part, let's say psychopaths aside, we all have that. We're all very much, uh, tuned into other people. Now, I've done a lot of research in my lab on this topic, and one of the complexities here, is that your brain cares about other people, but not everyone equally. So I'll just spend 30 seconds talking about one project we did where we have, you're in the brain scanner and there's six hands on the screen and the computer do, do, do randomly picks a hand, and then you see that hand gets stabbed with a syringe needle, and that activates this pain network in your brain.

It's not your hand getting stabbed. Nonetheless, your pain matrix goes off. That's empathy. I'm living what's going on with that hand. But now we add a one-word label to each hand. Christian, Jewish, Muslim, Scientologist, Hindu, atheist, Boo boo, boo. But the computer goes around, picks a hand, you see that hand gets stabbed.

And the question is, depending on what your in-group is, do you care as much about the outgroup getting stabbed? And turns that you don’t. It, it turns out that we're very hardwired to care about our in-groups and less so about our outgroups. And so this is one of the big things that I'm researching and so on, is how do we, how can we expand that?

The, the, the good and bad news is our, our empathy groups are extremely flexible. So in the next round of the experiment, what I did is I said, “Okay, the year is 2025. These three religions are teamed up against these three religions.” So now a religion that you didn't care at all about a minute ago is now your ally. And suddenly when you see that one gets stabbed, you kind of care about it more.

[00:48:29] Chris Anderson:
So that, that’s actually hugely helpful, isn't it, David? Cause that means that even though there's, there's a hardwired difference between in-groups and out-groups, what goes into those groups is actually malleable.

[00:48:39] David Eagleman:
That’s exactly right. Part of the interesting future that we have here is learning how to complexify relationships so that even if you're two opposing groups on some topic, you figure out where there's something to come. There are ways I think that we can do this algorithmically with social media. This is what I'm working on now, is how do we make it so that instead of just posting the social media post that makes us feel actually polarized, we post the cute puppy or whatever the thing is that makes opposing people feel like, “Oh yeah, we can bond on that. We can both like that thing.”

[00:49:10] Chris Anderson:
You were a disgusting Republican. I am a beautiful Democrat, but we are both TEDsters and so we love each other. That's what that's kind of, yeah. Think about that.

[00:49:21] David Eagleman:
Well, it's because of that flexibility. It's because of that flexibility. There's plenty of ways.

[00:49:27] Chris Anderson:
Steven, who's up?

[00:49:28] Steven Johnson:
Uh, I, I'm Steven Johnson. Um, I guess my first question is, “Chris, what are you doing in my chair?” Um, no, uh, for, I just wanna say it's so great to see a master interviewer at work. Huge shoes to, to fill. Um, honored to be taking this on. Um, I wanted to ask kind of building on, on that question in way, a little bit about hard wiring and about emotions. We've talked a lot about senses here, but a little less about emotions. And um, one of the debates in the field over the, you know, five or ten years or so is about universal emotions, right?

We'd had this long theory that there were these, there's this kind of central set of five or six or seven universal emotions that seem to show up in all human societies, and that's been challenged a bit in recent years. And this more, this idea of constructed emotions, uh, and arguments that we don't really have that universal palette. Curious where you come out on that question.

[00:50:19] David Eagleman:
I, I think they are universal. This is something that Charles Darwin after he wrote, um, you know, his famous book, uh, wrote a book called, uh, on the Expression of Emotions in Man and Animal, and he pointed out that, you know, even across animal species, you see the same kind of physical expression of emotion, presumably, you know, when parenting young, when facing a threat, stuff like that.

And one of the things Darwin did, you could still do is travel anywhere in the world. And you see the same kind of physical responses when someone is in fear or in love or whatever's going on. I mean, we just busted out of Africa a very short time ago. It's not like there's been time to change something fundamental about brains. So, so this is a very fundamental thing that we all have in common.

[00:51:06] Chris Anderson:
This, this makes me wonder whether one of the big problems in the world is that the brain is so exquisitely attuned to notice difference, um, if emotions are a human, uh, they're a universal human trait. Um, and they're actually in many ways the most important things to us, like how we feel, who we love, what we yearn for.

If those are actually common to all humans, then it's kind of a tragedy that we're distracted by and obsessed with what are smaller differences. Like here is someone who is Chinese, here is someone who is American. We are all terrified right now that those nations are on this sort of inevitable clash towards each other.

How do you change the conversation? How do you get human brains to say, stop thinking about that? That is not as important as the fact that they love. They love. They hate. They hate. They're fearful. They're fearful. We, we’re, we're at the heart. We on everything that actually matters, there is so much commonality. Can we trick our—can we hack our brain so that we do, we stop obsessing over what doesn't matter as much?

[00:52:18] David Eagleman:
Yeah, so I mean, a big part of this is metacognition, which is just a term that means thinking about your thinking. And so a, again, this comes back to this issue of how we educate our children. As we get better at teaching this kind of thing, we say, “Hey, look. Yeah, you're gonna feel in-group, out-group polls for towards different people and so on.”

But I want you to think about that. I want you to take Chris Anderson's point of view from the TED stage about what this means. But I also think we can engineer our social media in much cleverer ways to make it so that we're looking for the commonalities, so that when you're dealing with someone online, you see all the reasons why you're their pal.

[00:52:55] Chris Anderson:
Just identify that a bit more. ‘Cause it does, it does seem an incredibly disastrous fact that we've given AI so much power to hack our brains and trick us into play the attention game with them. You think that there's, there's different design things that could amplify different aspects of the human brain?

[00:53:13] David Eagleman:
Exactly. Yeah, of course. It's just a tool and we happen to have done it one way, which has allowed, you know, it's useful for advertisers to know, “Hey, I want to hit this group cuz they all believe xyz and so”, but we can easily make algorithms for unity instead of for polarization.

[00:53:28] Chris Anderson:
Wow. Last question.

[00:53:30] Audience Member:
Ah, David. Rick Smolen. I loved your talk about Mr. Potatohead many years ago. And, uh, Jaron Lanier many years ago here at TED, uh, was one of the first people to share virtual reality with us. And he talked about the fact that people had put on these helmets, they could become a, a creature. It was incredible how quickly they could adapt.

You and I talked about a book called The Ship That Sang by Ann McCaffrey. Do you see that as a, as something in the future, as someone that's, uh, locked in syndrome, for example, where, um, where a human brain can suddenly be powering, um, something that, that, that the rest of humanity needs because they can't use their body anymore? Maybe with the malleable—malleability of the brain is something that we can use to our mutual advantage.

[00:54:14] David Eagleman:
Yeah. Thanks, Rick. I love that question. Um, I devoted a whole chapter of my book, Live Wired, to this issue of “what is the self?” And by the way, so, so not talking about senses coming in, but about motor control going out and, and the hypothesis I proposed is that what becomes the self is what you can control.

So I realized, oh, I can control my arms and my leg going great. So that becomes part of me. And as I learn how to control, other things, like a spaceship or whatever, that can become part of my body, my myself. And by the way, I think this is why when you look at yourself in the mirror, you say, “Oh yeah, that's me, because I can control that reflection.”

Um, and, and it becomes part of me. But of course, there are all kinds of, you know, um, problems where somebody, like, can't use their arm where they say, This arm is not me. I don't know who put this thing here, but, um, I gotta get rid of this. It's not part of me. So I think we're gonna be entering a future where, as we do invasive brain implants and so on, we'll be able to control robots and things.

I'll be able to have part of myself on the other side of the country or maybe on the moon or something that I'm controlling and I'm mining for chemicals or whatever it is. And it's a more extended version of myself. I'm really interested to see what happens in that future.

[00:55:25] Chris Anderson:
So, David, this was, uh, this was extraordinary. If people want to keep up with you and what you're thinking about, what's the best way for them to do?

[00:55:32] David Eagleman:
eagleman.com.

[00:55:33] Chris Anderson:
eagleman.com. Um, I dunno about you guys. I mean, you by the way, you are an extraordinary audience and so, wow. Uh, this was a co-created experience and, um, kind of, kind of blew my mind. David Eagleman, thank you so much for this.

[00:55:49] David Eagleman:
Thank you, Chris. Thank you guys.

[MUSIC]

[00:56:02] Chris Anderson:
Okay, that was David Eagleman at the TED Conference. So look, like I said at the beginning of the show, this is the last episode I'm fully hosting, although you will actually hear me again in the next episode where I have a conversation with the new host of this incredible show, author Steven Johnson.

Steve is amazing, spoiler alert. So look, it's been an absolute pleasure to lead these conversations so far, and I'm even more excited to see where they go next. And don't worry, I'm not going far. If you want to get in touch, if you have feedback on the show so far, suggestions for the future. I'm still at TEDchris@ted.com. That's TED— c-h-r-i-s at TED dot com. Now the TED interview is part of the TED Audio Collective.

This episode was produced by Allie Graham and our managing producer Wilson Sayre, and brought to you by TED and Transmitter Media. Sammy Case is our story editor. Fact-checking by Jen Nam. Farrah Desgranges is our project manager.

Gretta Cohn is our executive producer. Special thanks to Michelle Quint and Anna Phelan. I'm your now former host, Chris Anderson, saying thank you so very much for listening and being part of this journey.