Ep54 "Where do you end and others begin?"

From the brain’s point of view, what is the self? How do 30 trillion cells come to feel like a single entity? Does the "self" of a blind person include the tip of her walking stick? How flexible is our sense of self? And what does any of this have to do with psychedelics, trauma, synchronized swimmers, religious rituals, cheerleaders, or why soldiers across time and place love to march in lockstep? Join Eagleman for this week's episode of surprises about how the brain computes the self.

Episode Transcript

Speaker 1 (00:04):
From the brain's point of view, What is the self?
How do you put together thirty six trillion cells and
have it feel like one thing? Does the self of
a blind person include the tip of the walking stick?
How flexible is our sense of self? And what does
any of this have to do with psychedelics or trauma,

(00:27):
or synchronized swimmers, or religious rituals or cheerleaders, or why
soldiers across time and place love to march in unison
in lockstep. Welcome to Inner Cosmos with me David Eagleman.
I'm a neuroscientist and an author at Stanford and I've

(00:48):
spent my career at the intersection between how the brain
works and how we experience life. So I'm going to
beget in today's episode with a question that I've wondered

(01:09):
about since i was a kid. Something I've always found
amazing is watching armies, thousands of soldiers march in perfect lockstep.
And even as a kid, I noticed that across the world,
all armies did this and this goes back to the
earliest days of armies. And I know this because when
I was younger, I read about how the Romans discovered

(01:31):
a problem where if they marched in lockstep over a bridge.
It would sometimes hit the resonance frequency of the bridge
and then it would collapse. So they learned from their mistakes,
and whenever they came to a bridge, they would purposely
go out of sync with one another and they would
cross the bridge that way. But the point is that

(01:52):
they normally marched in lockstep. They, like all modern armies,
loved acting as a mega organism. So why do armies
love to synchronize? I mean, why not just have all
the soldiers walk asynchronously however they want to, as long
as they keep up well. One hypothesis would be that

(02:15):
an army marching in lockstep is intimidating. You see something
coming at you. That's like a giant, unified, single minded monster.
And a related hypothesis could be that an army stepping
with precision timing represents discipline and training, the way we

(02:36):
watch dancers or synchronized swimmers, and across sports like ballet
or cheerleader or whatever, athletes pursue this kind of perfect synchronization.
In other words, the army does it not just because
it's scary, but also because it represents discipline and training
to get there. And these both seem like reasonable hypotheses.

(02:58):
But I have something else to segest today, something that
I think you might find quite surprising and hopefully enlightening
because of all the other things that it sheds light on.
So what seems like an arbitrary question can sometimes unearth
a lot. But first, let's start at the beginning. So

(03:18):
let's step back to sixteen thirty seven, when Renee de
Kartes famously wrote Japan's don't suis I think? Therefore I am?
Now when he says I, we all understand what he
means here, we think, but what exactly is the I
If you think it's obvious what the self is, get

(03:40):
ready for some eye openers, because we're going to see
how the self emerges from computations in the brain and
how it can morph in unexpected ways. So let's start
by noting that nothing seems more obvious than you feel
like a single entity. But that's strange because you're actually

(04:01):
built out of thirty six trillion individual cells communicating through
chemical and electrical signals. But you don't feel like that.
You don't feel like a swirling bath of seven billion,
billion billion atoms, not to mention that you're constantly shedding
atoms and gaining new ones, such that your body is

(04:23):
composed of entirely new atoms about every seven years. Despite
all this, you feel like one stable thing. You feel
like you. You have a name, You have a history
and a memory, and a personality. You have desires, and
you are unique personality. You have a self, and that

(04:44):
self seems to be located right behind your eyeballs. Now
this is wild, right, because consider other scenarios in which
there are lots of pieces and parts working together. Let's
say I go out to some big field and I
set up a bunch of and pulleys and levers, and
I start hooking everything up and this turns that, and

(05:05):
that affects that, and this lever pulls that thing, and
I start adding more and more parts in this big
crazy machine gets larger and larger. Here's the question, At
what point do I add one more lever and I say, ah,
Now this is no longer a Frankensteinian collection of trillions

(05:26):
of individual pieces, but suddenly it has the experience of
a living unity. Or just take your computer. It's made
of billions of transistors and resistors and capacitors. It's sending
zeros and ones all around. But the question is does
your MacBook pro have a sense of itself? Do you

(05:50):
think it ever aspires to be something greater in its life?
Or does it feel a sense of embarrassment and its
performance sometimes, or does it ever desire to be loved
by another computer? Now, the reason your sense of self
is so mysterious is because your brain is just made
up of pieces and parts cells with straightforward properties, each

(06:13):
cell by itself as just doing basic sell things. So
why does this giant collection, when hooked up and interacting
in the right way, have a unified sense of a
single you interacting with the world through time. You have
this conscious perception of yourself as a thing such that
the thirty six trillion cells that comprise you can collaborate

(06:37):
to go to a dance club tonight, or meet friends
at the coffee shop, or go to a bookstore, or
take a road trip across the nation, acting like a
single thing. So why do you feel like a unified entity? Now?
The answer, presumably is an evolutionary one. Those cells are
all hanging together, and this collection has to take the

(06:58):
whole vast complet space of possibilities and crunch it down
to a single decision. For example, your body can go
to the left or go to the right to get
around the tree, but you can't do both, and that's
why you have to squeeze down all the chattering of
billions of neurons to a single choice and control your

(07:22):
trillions of cells to do something that makes sense in
the outside world. I've mentioned before that the brain is
typically celebrated for its parallel processing, but in fact, just
as importantly it should be celebrated for its serialization. In
other words, its ability to conclude something, to decide something

(07:43):
from the vast space of possibilities, to take all the
rumbling trillions of cells and get to a single conclusion
about what to do next. So that's presumably why you
have a unified sense. But the story gets stranger from
here because the sense of self is not fixed, it's

(08:05):
not nailed into place. Instead, it's quite fluid, and in
many scenarios what we find is a dissolution of the self.
For example, various drugs can have profound effects on an
individual's sense of self. They lead to an alteration of
one's identity. And this is amazing, right, because these are

(08:28):
invisibly small molecules with particular shapes, and when they enter
your system and bind to particular receptors in your brain
and change the activity just a little bit, then this
neural technology that builds selfness breaks down. For example, a
lot of psychedelic drugs do this. They bind to particular

(08:51):
receptors here and there, and they cause profound alterations in
the feeling of self. Think of LSD or SILAS or DMT.
What happens when people take this is they report a
dissolving of their ego boundaries, leading to experiences of what's
sometimes called an ego death, meaning the loss of self identity.

(09:16):
You also have substances like ketamine or PCP or some
synthetic cannabinoids, and these can trigger feelings of depersonalization and dissociation.
In other words, people on these drugs get a sense
of detachment from their own body, or their emotions or
their surroundings, so they have a distorted perception of self.

(09:40):
And you sometimes see this with certain psychiatric medications when
they're misused or taken in appropriately. They can alter cognition
and emotion and often lead to a feeling of disconnection
from a person's identity or sense of self, and all
throughout the drug world, you find people mixing different drugs
together and getting all kinds of severe things like dissociation

(10:04):
and confusion and a loss of coherent self awareness. So
what does this tell us? In all these situations, we
see how invisibly small molecules can disrupt the normal, very
delicate functioning of the brain, and that busts up the

(10:25):
computation of the self. And you can find the same
thing not just from the influence of molecules, but also
from the influence of experiences. Just look at something like
post traumatic stress disorder. Beyond the emotional challenges that we
find there, we also find cognitive impacts like a pervasive

(10:47):
sense of disconnection from one's identity and a loss of
coherence in self perception. For example, sometimes people report feeling
like an object rather than a person. Now, what happens
when we measure the effects of post traumatic stress disorder
in the brain. While there's a network called the default

(11:08):
mode network, and this network is critical for constructing one
sense of self, and in post traumatic stress disorder, for example,
you can find in neuroimaging that the connectivity gets disrupted,
and this appears to correlate with problems with one's perceived
sense of self. This feeling that people sometimes have in

(11:32):
post traumatic stress disorder, where they say they don't know
who they are, where they feel like they've stopped existing.
What this reflects is a disruption in their networks that
are critical to computing the self, and we see disruptions
of the self in closely related clinical settings also, for example,
in dissociative identity disorder. This is where people usually who

(11:56):
have been through some trauma, will have a fragment of
their self into different identities. They switch personalities. They can
have these sudden changes in mood and in their behavior,
and family members can usually tell when a person switches
their personality. And by the way, they often get amnesia.

(12:17):
They can't remember what they said just a few minutes
ago when they were speaking as one of their other personalities.
I'll just note that often people with dissociative identity disorder
are misdiagnosed as having schizophrenia because their beliefs are interpreted
as a delusion. But I think more properly this could

(12:37):
be interpreted as yet another demonstration that the brain has
to go through an enormous amount of very delicate work
to construct the self, and there are lots of ways
this can be disrupted. Now, how can we study this?
In the lab, one of my colleagues at Stanford, Joseph Parvizi,
was studying patients with epilep see people who have electrical

(13:02):
seizures in the brain. So one day one of his
patients with APLEPSI tells him every time I have a seizure,
I have a sense of depersonalization and dissociation. Everything's unreal,
It's like it's not happening to me. And Parvez finds
out that this patient's seizures started in a tiny brain

(13:22):
area right in the brain's midline, called the anterior precuneus.
And there was something very interesting about this area because
it's not part of the default mode network, which I
mentioned a moment ago, but instead it's a node at
the center of a different network consisting of different areas.
And this network integrates data about where you are and

(13:45):
how you're moving, and where your muscles and joints are,
so it's involved in building a mental map of your
physical self. Now, just before I tell you more about this,
one of the things I think is interesting is how
parvs this ditinguishes between the I and the me. He says, Look,

(14:05):
for every action we take, even during dreams, there's always
an agent behind it. We call that agent I. But
me is everything we have stored in our memories about
the I. In other words, the eye has to do
with your sense of your body in the immediate here
and now, with a particular point of view, a first

(14:27):
person perspective that belongs to only you. But the me,
that's the narrative self, that has to do with actively
or passively thinking about your past life or planning your future,
things like memory and habits and personality, emotions, feelings for others,
what lies ahead, and so on. Okay, now here's the

(14:49):
key point from the brain's point of view. These two
functions of the eye and the me, they're actually underpinned
by separate networks of brain areas. These networks interact, they're
not the same. So the me involving my memory, inhabits
and personality and emotions, that mostly involves the default mode network.

(15:09):
But the eye, which gives my sense of my particular
point of view right now, that involves this other network
where the anterior precunius sits at the center. And what
Parvizi found is when that network becomes disrupted, let's say
by an epileptic seizure that disrupts your self in the
here and now. So he stuck electrodes into the anterior

(15:34):
precuneus and zaps with electricity, and people say that something
weird happens to their sense of physical self. They get
a depersonalization, similar to what happens with psychedelics. It's not
an out of body experience. People still feel like they're
in their bodies, but they generally feel like there's a
change in their orientation or their location, depending on where

(15:57):
the stimulation happens. They feel like they're floating, your sinking,
and it doesn't make any sense when they look around
and they see where they are. And so their report
was that the world around them seemed unreal. So again

(16:28):
I want to be clear that you require this extraordinarily specific,
delicate operation of multiple networks in the brain to make
you feel a particular way, to give you an eye
that's anchored in space with a point of view, and
a me with a stable sense of who you are,

(16:49):
and a connection to your memories and your sense as
an individual. Now, assuming you have average good luck, then
you'll never even be conscious of this perspective on the world.
But if your brain gets disrupted from drugs or trauma
or epilepsy, you're suddenly going to see it. Your world
will seem unreal, and you'll come to understand that the

(17:12):
self is a construction of the brain and needs all
the pieces and parts to be running just right. Okay,
so what we've talked about so far is the way
the self can get disrupted. But now I want to
switch gears to a less studied area. Instead of the
dissolution of the self, I want to consider the expansion

(17:36):
of the self. Now. I started thinking about this many
years ago, even when I was a kid. I noticed
that when you ride a bicycle, and maybe you accidentally,
without meaning to, you run over a little worm that's
crawled onto the sidewalk, and you recoil as though you'd
physically stepped on the worm yourself with your bare feet,
even though it was only the bicycle that touched the worm.

(17:58):
So I started wondering if the bicycle becomes essentially a
part of you, an extension of the self of some sort.
And then when I got to college, I ended up
reading some philosophers like Maurice Merleau Ponti and Gregory Bateson
who posed a question like this about a blind man
with a stick. The question was where does the blind

(18:21):
man's self end and the rest of the world begin.
You can think of the stick as like an extended
cognitive system that pulls in information from the world. So
does the blind man end at the handle of the
stick or at the tip of the stick? Or does
his self end somewhere in between? As Merleau Ponti wrote, quote,

(18:44):
the blind man's cane has ceased to be an object
for him. It's no longer perceived for itself. Rather, the
caine's furthest point is transformed into a sensitive zone end quote.
In other words, since the world is a deserved through
the stick, it becomes part of the man's self. So

(19:05):
humans alter the borders of their self all the time
by using new instruments. I talked way back in episode
two about dogs who learn how to ride skateboards, and
even though wheels are not a part of the evolutionary
history of canines, it becomes part of the dog. They
become one with the skateboard, and I talked about surfing

(19:30):
dogs even though the dog skeleton didn't evolve to be
big and long and flat. The dog has no trouble
incorporating the surfboard into its body plan into itsself. So
we're not limited by the borders of our skin, but
instead these self can expand. And I've also previously mentioned

(19:51):
some experiments that were done years ago where a monkey
learns to use a little rake to get some food
that he couldn't otherwise reach. And once the monkey becomes
proficient at this, there are cells in its brains sells
that command actions and sells that sense what's going on.
These cells change to include the rake in the space

(20:13):
that they care about, what's known as their receptive field.
In other words, the rake literally becomes part of the monkey.
So whether we're talking about bicycle tires or walking canes
for the blind, or the monkey and the rake, we
see that the notion of the self has flexibility. It's
not something that's just genetically pre programmed and fixed into place.

(20:38):
So how does the body decide what to include what
makes up the self? Well, in my last book, Live Wired,
I proposed an answer to this. In part, it's about control.
If the brain can control something, it becomes part of
the self. So, for example, when my brain sends out

(21:00):
signals to move my arm. My arm follows the commands,
and therefore it becomes part of my self. The monkey's
rake becomes part of what it can use and command
in the world, so it becomes in a sense, part
of its body. Now. Fundamentally, remember the brain is locked
in silence and darkness, and so what does command mean

(21:22):
to it? Fundamentally, it's all about prediction. Now. In an
earlier episode forty four, we dove into the issue about
the brain being a prediction machine. That's all it's trying
to do. Locked in silence and darkness, It's trying to
figure out what's happening in the world out there, And

(21:42):
for really sophisticated brains like ours, it's not just about
reacting to what happened, but instead having a model of
the world that makes predictions about what will happen. So
given this, what else can become a part of the cell.
We are used to our brains controlling just our limbs,

(22:04):
and this is because evolution has built us with muscle
and tendons and nerves. But evolution never came up with
controlling distant limbs via bluetooth. So in theory, if you
could control a robotic arm with your brain, or a
metal avatar that's all the way across town. This would

(22:24):
become part of your self. And one question is what
consequence would this have for your conscious experience. The answer
is that the robot or the avatar would be perceived
as a part of you. It would be another limb.
It would be an unusual limb because of the physical
gap between you and it, but it would nonetheless qualify

(22:47):
as an extension of you. Think of the Avatar movies.
The protagonist Jake Sully thinks of something he wants to
do with his limited body, and the eight foot all
avatar moves accordingly, and therefore the avatar becomes an extension
of his self. By the way, you see this all

(23:10):
the time. In the military. A soldier is in charge
of driving a bomb sniffing robot, and everything the soldier
commands with his joystick, the robot does. And at some point,
if the robot gets blown up, it's not unusual to
see one of these soldiers crying and heartbroken. It's like

(23:31):
a part of them physically has been lost. Now, if
this kind of extension of the self seems strange, just
remember that you have everyday experience with this. Whenever you
look in a mirror and move your body around, you
see a distant object move in perfect synchrony with your

(23:51):
motor commands. Your brain says, lift your arm, and you
see this thing across the room, lift its arm. It's
a perfect prediction. And so when you do that, you
understand the reflection as your self. You don't feel any
direct sensation from the distant limbs, but your brain registers
the prediction. Every time I send out a command for X,

(24:15):
that body over there does X, and that's enough for
your reflection to become a member of the selfhood tribe.
And one of the things I've written about recently is
expanding oneself using virtual reality. You're in a virtual world
and you raise your arm and you see your virtual

(24:36):
avatar and the virtual mirror raise its arm. You tilt
your head and it tilts its head. Now, interestingly, people
are studying this in the context of empathy, because you
can put someone else's face on the virtual avatar. Let's
say someone of a different gender and a different race,
and the question is how do you feel after having

(24:58):
them be a part of you for a while. And
you can experiment with very different kinds of bodies in VR.
What if in a VR world you're one hundred feet tall,
or you have eight legs or three arms. In all
of these cases, you can learn to control that body,
to predict what's happening, and then that body becomes you.

(25:21):
The identity of the self is surprisingly flexible. So what
I've proposed is that what the body can control becomes
the self. And this all pivots on predictability, and so
one tragic lesson we can glean from this is what
happens when a person gets damage to their peripheral nerves

(25:44):
so they can no longer control their limb. And what
happens is they can get a disorder called asomatic nosea,
which means they now deny ownership of the limb that
they can't control. So as somatic nosia means not knowing
one's body. And in the clinics you'll find the strangest

(26:04):
things where somebody will say this leg does not belong
to me, and sometimes they'll insist that the limb belongs
to somebody else. They'll attribute the leg to, say a
dead friend or a relative, or a phantasm or a devil,
or one of the doctors taking care of them. They'll
say the leg was sewn onto her, but it's not hers.

(26:28):
She'll explain that her own real limb was stolen or
is simply missing. And in variance of this disorder, people
will sometimes construe the limb as an animal, perhaps like
a snake, with its own independent life force and intentions.
But the point is it's no longer a part of
their self. So I was surprised when I found there

(26:51):
was no gold standard explanation for this in the literature.
But you'll have no trouble guessing my proposal, which is
that the brain can no longer control the limb, and
so the limb falls from the brotherhood of the self.
By the way, sometimes these patients have a small window
of lucidity in which they re recognize their limb as

(27:14):
their own, but it doesn't last long. I hypothesize that
this might result when the leg happens to move the
way that they had intended accidental predictability. That might be
a feeling of wanting to move the foot to the left,
and then the foot happens to move that way, which
leads the owner to take credit for the action. And

(27:37):
given a person's lifelong experience of controlling her leg It
should come as no surprise that even a temporary impression
of control can snap it back into alignment with the self,
even if just for a moment. So what you can
predict becomes part of the self. Now. One of the

(28:14):
places this becomes really interesting is with relationships, because when
you come to know someone well, you in a sense
expand yourself. They become a part of you. Again. This
is because the brain is a prediction machine. You've spent
a lot of time with the people in your life,
and so you have rich predictions about them. You have

(28:38):
increasingly sophisticated guesses about what they're going to do in
some situation, and in this sense they become a part
of you. Now, your predictions about other people are never
going to be perfect, and those people will often surprise you.
And so the degree to which your spouse or friend,

(28:59):
your family member remains unpredictable is the degree to which
she or he remains different from the self, remains independent
from you. Nonetheless, they are, to a greater or lesser degree,
a part of your brain's notion of the self, because
you have some degree of prediction about them, and as

(29:22):
a result, you can be proud of their accomplishments and
feel happy when they're happy, and sad when they're sad.
And part of what's hard about a breakup or the
death of a loved one is it something like a
self contraction. Okay, so now we're set up to return

(29:42):
to the question that I posed at the beginning of
the episode. Why do soldiers march in lockstep? And I
think you can now guess my hypothesis. It's not just
about intimidation, it's not just about discipline. It's about giving
each soldier the usion of a larger self. If you

(30:04):
are an individual soldier, you experience this expansion of the self,
this enlargement because there are all these other bodies moving
in a way that is precisely predictable by your brain.
Your brain sends out motor commands that say, okay, stomp
my right leg exactly now. And after that command goes

(30:27):
out from the brain and down the spinal cord, it
witnesses the power of a thousand legs, all stomping at
the same moment. Your brain has sent out a command,
and you feel the earthshake as a result. It's empowering
to be part of a group because your self now
consists of thousands of bodies. There are a dozen ways

(30:51):
to look at this issue of marching in lockstep socially,
but from the neuroscience point of view, when you do
stuff in synchrony with others, there's an expansion of the
brain's construction of this self. So this is my hypothesis
for why we see so much synchronization around us. You
see this in Japanese festivals where everyone is doing the

(31:13):
same thing at the same time. Or take the Hodge,
which is this annual Islamic pilgrimage to Mecca. You've got
pilgrims from all over the world travel to Mecca to
flow around this big cube at the center of the
Grand Mosque. Is very stunning to see hundreds of thousands
of bodies swirling like a larger mega organism. And this

(31:38):
is typical of religious ritual. If you only knew neuroscience
and knew nothing about societal behavior, you might predict the
existence of this sort of thing because the commands from
each pilgrim's brain is multiplied by the feedback from hundreds
of thousands of other pilgrims, and that kind of feedback

(31:59):
is intoxicating to human brains. And as I said, you
find this sort of synchronization in all religious rituals. Everyone
is doing the same thing at the same time, ideally
in the same costume. And I propose that it's not
accidental everyone stands and sits at the same time, or
genuflex or chants. When you look across religions, I suspect

(32:23):
that the details of the rituals don't matter much at all. Instead,
it's the allure of learning how to fuse your identity
with a larger group. You think, wow, I can learn
the steps, the moves, the words here and be part
of a larger self. That is the promise that is
being offered to you. You never find religious rituals where

(32:48):
everything is desynchronized, where the promise is come into my religion,
where we each do our own thing. You walk in
whenever you want, you face wherever you want, Everyone sing
and chant out of tune. You just don't see religions
where there's no bigger voice, no bigger self acting in unison.

(33:08):
And of course you find exactly the same synchronization in
non religious ceremonies. One hypothesis about the origin of music
and dancing is that this came from early primates who
would synchronize with one another, and when we dance, we
see this. If you're an observer of human behavior, it's
hard to ignore that humans love to be synchronized on

(33:30):
the dance floor. And you can imagine a bunch of
early primates sitting around and all banging rocks together, making
shouts or chants that aren't random but synchronized. You can
see how the drive for a larger self could be
at the root of this. And when you start looking
for humans synchronizing, you see it everywhere. You see it

(33:52):
in group exercise classes like yoga or dance or aerobics.
Everyone's doing the same thing at the same time, and
that synchronization fosters this sense of unity. You get the
same thing in choirs where everyone sings together, or at
music concerts, where the crowds synchronize their movements to the

(34:13):
rhythm of the music. They sway, they clap, they sing
along together. At sports events, you have fans synchronize their
chance just like a protest marches. What's happening if you're
at the event is that your brain sends commands to
your larynx with the prediction that it will hear your
voice in return. But now you hear your voice times

(34:36):
a thousand, and you feel like your self is larger
and more powerful. So let's wrap this up. My interest
is in this question of where does your self end
and others begin? And although you think you end at
the borders of your skin, you're actually a flexible creature,
extending past what you can see and feel, incorporating it

(34:59):
tooferent times, your family, your partners, your teams, the culture
in which you're embedded. And I think looking at this
from the neuroscience point of view is a very powerful
way to understand rituals and dancing inquires and religious ceremonies.
Even on the political scale. It might shed light on
our study of in groups and outgroups, and our understanding

(35:22):
of things like patriotism. And this all fundamentally comes down
to an extension of this self, which always reminds me
to question, what would happen if you were born in
a different culture, a different neighborhood, a different era in time.
Would you be you? Presumably not in a way that

(35:42):
we would recognize. You are wired up by the world
that you happen to be in. All of it, to
a lesser or greater degree, becomes part of what your
brain considers your self. So I'm fascinated with this question
of how we draw the limits of our selves. For example,
I'm thinking some thoughts, and I jot notes throughout the week,

(36:05):
and I go into my studio and record this podcast,
and you listen to it. But it might be a
week later after I've recorded it, or maybe you are
listening to this long after I'm dead, and yet we're
still communicating. I'm taking ideas from my head and capturing
them in zeros and ones stored on a server somewhere,

(36:26):
and eventually that gets transmitted over the Internet or maybe
in a century, over Internet twelve to your device, and
then my words reach you, and you're suddenly connected with me.
I'm right next to you, I'm in your ear, I'm
in your brain. My words make physical changes to the
networks inside your head. And if we're alive at the

(36:49):
same time, you can send me an email and I
read the words on the screen that you wrote, and
we are connected. And with our current communication technologies, this
is more true than ever that our brains have the
opportunity to expand the self, from literature to television, to
podcasts to the Internet. We increasingly have the opportunity to

(37:13):
become larger than we would otherwise be. Please visit eagleman
dot com slash podcast for more information and to find
further reading. Send me an email at podcast at eagleman
dot com with questions or discussion, and check out and
subscribe to Inner Cosmos on YouTube for videos of each

(37:36):
episode and to leave comments. Until next time, I'm David
Eagleman and this is Inner Cosmos