My name is Laura Heisler, and I am the director
of the Wisconsin Science Festival,
and we are delighted to be partnering again this year
with the Book Festival.
Just a few words about our author.
We are so delighted to have Anil Ananthaswamy here
to talk about his latest book, "The Man Who Wasn't There:
"Investigations into the Strange New Science of Self."
Mr. Ananthaswamy is a consultant and the new scientist
in London as well as a contributor to
National Geographic News.
Years ago, he worked as a software engineer
in Silicon Valley before training as a journalist
at the University of California at Santa Cruz.
He is also a Ted speaker and is the author of
"The Edge of Physics."
So today we are delighted to welcome him
to hear about his most recent book,
"The Man Who Wasn't There."
Please join me in welcoming Anil Ananthaswamy.
(applause)
- Thank you for that introduction.
Thank you, everyone, for coming.
This is a pleasure for me to be coming
and speaking at the Wisconsin Book Festival.
The last time I was here in Madison it was in April,
and it was really cold.
And it's lovely, it's lovely to be back here now.
Today, I'm going to speak about the human sense of self.
About who we are.
And specifically I'm going to talk about
what neuroscience in general,
and neuropsychology in particular,
is telling us about our sense of self.
About when you ask the question, "Who am I?",
the kind of answers we come up with.
What does neuropsychology have to tell us about
how our self is formed our what that self is?
Normally, if you were to ask anyone,
"Who are you?" you'll get a whole range of answers,
and we all have an intuitive sense
for what our sense of self is.
It's there when we wake up, and it kind of disappears
when we go to sleep, reappears when we are dreaming.
And also, there's this sense we all have,
in fact all of us will be experiencing this right now,
the sense of being a body.
A sense of being in a body,
occupying a volume of space that is taken up by this body.
Having a sense that we are viewing the world
from within our heads, looking out.
Having a sense that whatever we
are experiencing is private to us.
That there is a kind of first person perspective,
that each perception that I'm having
is somehow mine and mine alone and distinct
from what somebody else might be experiencing.
There's also a sense we have of a continuity in time.
You can think back to your earliest memories,
or you can imagine yourself 10 years from now,
some future imagined self,
and you have this sense that there's this same entity
that is persisting over time.
All of these things, in some sense,
go towards making up our sense of self.
So, if you were to ask someone, "Who are you?"
you're going to get answers that tease out
these various aspects of being human.
Now, when I pose it like that, you might wonder,
so what really is the mystery?
What is there to explain?
We all know what this self is, and what's the big deal?
In a larger set of the mystery,
I just want to read this quote by philosopher Thomas Nagel,
which says it very poetically
"It seems outlandish that the centerless universe,
"in all its spatiotemporal immensity,
"should have produced me of all people.
"There was no such thing as me for ages,
"but with the formation of a particular physical organism
"at a particular physical place and time,
"suddenly there is me for as long as the organism survives.
"How can the existence of one member
"of one species have this remarkable consequence?"
And that is the essence of the mystery,
and any time philosophers, neuroscientists,
theologians have wondered about the nature of the self,
they ended up in debates.
It's not an easy question to answer in terms of
what is the self, and the debates kind of,
these are the broad brush strokes of the debate.
First of all, they argue about whether is there self
or is there no self.
And it's as basic as that.
The other thing they wonder about is,
can the self exist independent of all else?
And what I mean by that is we know
that the material world can be broken down eventually
into fundamental particles.
We know that the material world is constituted of these
fundamental particles like electrons and quarks and gluons.
And when it comes to the self, the question is,
is the self independent of these material
constituents of nature?
Can it exist separate from the electrons
and quarks and gluons that make up the material world?
What philosophers call ontological reality.
Does the self have a reality that is separate
from the material world, or is it something that comes about
because of the interactions of the material world?
And then you must have heard over the last year,
last few years, the last few decades,
about this idea that the self is an illusion.
Well, if the self is an illusion, then whose illusion is it?
Is there somebody,
something experiencing the illusion?
What does that mean to be even saying
the self is an illusion?
So all of these things are the broad kind of debates
that go on within philosophy, neuroscience,
and theology about the nature of who we are.
And so I just wanted to, today,
talk about a few things that can lead us to a point
where we can appreciate what these philosophers
are debating about.
And I can give you a spoiler alert right away
that there are no answers.
We still haven't figured out what the answers are.
But it's still very hard to appreciate
what the debate is about,
what the philosophers and neuroscientists
are wondering about.
So, in a sense, what my book tries to do
and what I'll try to do in this talk very briefly
is bring us to a point where we can understand
what are they arguing about.
The first thing to look at is what are the key aspects
of the self that concern philosophers and neuroscientists.
There are two things primarily.
One is called synchronic unity.
If you think about yourself right now,
all of you are looking at the stage,
you're getting a certain visual input through your eyes.
You're also hearing me speak,
so you're getting a sensation of sound.
Most of you would be feeling like the perception
that arises from sitting on your chairs,
the tactile sensations of you clothes on your skin.
And what's interesting and not at all trivial to explain
but might seem trivial is that all of these sensations,
whether it's vision or sound or tactile,
they're all being experienced by the same entity.
It's not as if one person is hearing the sound,
another person within you is hearing or is seeing things,
yet another entity is experiencing touch.
All of these sensations are being experienced
by the same thing or, you know, same person.
You struggle for words at this point.
What is this thing, or what is this entity
that is actually experiencing the various perceptions?
And there is a kind of unity to everything
that we experience in a given moment here and now.
Again, from an experiential point of view,
from the point of just being a human being,
it seems very trivial.
Yeah, of course that's how it is.
But trying to explain that philosophy,
trying to explain that unity philosophically
or neuroscientifically is not easy.
And, in fact, that's one of the things people fret about
when they try to explain the nature of the self.
So there is this unity of experience
of being here and now in a body.
There's also something called diachronic unity,
and this is something I just touched upon
when we think about our child or when we think
to our earliest memories or any memories
that we have of having existed.
And also if you imagine yourself in the future,
certain perceptions are going to arise in your mind,
some emotions are going to come up, and, again,
if you think about it a little bit,
no matter what you remember or what you imagine,
all of the perceptions that arise from the remembering
and the imagining seem to be happening to the same entity.
It's not as if when you think of your four-year-old self
you are aware of somebody else,
and when you imagine yourself 10 years from now,
you're aware that it's happening to somebody else.
No, it all feels as if there is the same entity
that is perceiving or is behind the whole thing.
Now, this is called diachronic unity.
And, again, it seems trivial, but it's not easy
to explain philosophically and neuroscientifically.
How does this happen?
In fact, it's because of the presence
of this unity that some philosophers have argued
that there must be something called
a self that must be behind all these experiences.
That must be experiencing everything
as if it happens to itself, and somehow it can put it
all together and say, okay,
here's a person that is experiencing existing over time.
But then there are other philosophers who argue otherwise
And how do we make sense of all this?
So, I'm going to just talk a little bit about the fact
that this whole exploration of the nature
of the self is not new.
It probably began the moment humans became self-aware.
The moment humans just realized that they were self-aware,
the questions began.
Who am I?
And on this screen I have an example of something that was,
I don't know if any of you would actually recognize
the script at the very top, but it's Sanskrit,
which is an ancient Indian language.
This particular poem, I've just taken a stanza from a poem
from the 8th century AD,
which is trying to answer the question,
"Who I am?" by trying saying what I'm not.
So it basically says, I'm not my mind.
I'm not my intellect. I'm not my body.
I'm not by emotions. I'm not my virtues.
And so on and so on and so on.
In trying to answer, "Who am I?" it's basically pointing out
that I am not all these various things.
So what must be left must be I.
Of course, this particular tradition
of asking the question, "Who am I?"
belongs to a very specific philosophical tradition
within India called non-dualism tradition,
and they have their own answer for the question,
"Who am I?"
I'm not particularly interested in the answer right now
because if you asked this tradition, you'll get one answer.
If you ask the Buddhists who go back 2,500 years,
they'll have a slightly different answer.
If you go back to other traditions,
whether in the east or the west,
each one has a slightly different take on
the answer to the question, "Who am I?"
This is a quote from Scottish philosopher David Hume.
This is a very often quoted sentence from his writings.
He says, "When I enter most intimately into
"what I call myself, I always stumble
"on some particular perception or other,
"of heat or cold, light or shade, love or hatred,
"pain or pleasure.
"I never can catch myself at any time without a perception,
"and never can observe any thing but the perception."
And what he's saying is that all we are
is a bundle of perception.
Bundle of perception.
So if you started trying to examine very, very deeply
as to who is doing the perceiving, you would find nothing.
And so David Hume falls into the camp of philosophers
who are called the bundle theorists.
And so on and so forth this debate goes on.
So somebody like David Hume is saying
you can examine as deeply as you want,
and at the end you will find nothing,
and it is somewhat similar to what the Buddhists are saying.
The previous slide I showed you
from the non-dualist tradition,
they have a slightly different take on that.
So, for the rest of us who are not philosophers
and not neuroscientists, how do we make sense of all this?
You know, what are they arguing about?
So that's what I tried to do in this book.
I look at eight different,
I looked at eight different neuropsychological conditions,
each one of which disturbs the self
in a slightly different way.
So, by self I mean just the experience
of being a human being.
We all know what that feels like,
and sometimes, whether you are, you know, ill or not,
sometimes during the course of your day
you can perturbations of the self.
If you, for instance, are feeling slightly depressed,
that is a perturbation of the self.
You feel differently when you're depressed
than when you're not.
And similarly, each of these neuropsychological conditions
change how one feels about one's self,
and by looking at what changes,
we can start asking questions about what the self is.
And so the conditions I looked at, Alzheimer's Disease.
Some of these you will be familiar with,
and some may seem, you know,
strange in terms of, by the fact that you may not have
come across this even in regular readings.
Body integrity, identity disorder, schizophrenia,
depersonalization disorder, autism,
autoscopic phenomena which include out-of-body experiences,
ecstatic epilepsy, and Cotard syndrome.
So I won't have, obviously,
time to go through each one in detail,
but what I want to do is kind of give you a sense
for how by talking to people who are experiencing
these conditions, how you might get an understanding
of what might be happening, A, to their own experience
of being a self and, B, what that tells us about
how the brain might be, brain and body together,
might be constructing the self in the first place.
And this tradition of looking at, you know,
or asking questions and trying to answer them
by looking at things that are not quite okay
is not very different from how brain science
has functioned over the last few decades.
For instance, when you think about how much
we've learned about the brain and the way it functions,
a lot of what, a lot of our knowledge has come about
because we have studied people
who have unfortunately have had a stroke
or some brain trauma or lesions and they've lost some part
of their functionality,
like maybe language skills or motor skills,
and by correlating that loss of functionality
with the damage to the tissue we have understood
how different parts of the brain might be doing
what they're doing.
And this approach of looking at neuropsychological condition
that change the self in some way is not very very different.
In a sense, you're looking at
changes to the self and then trying to correlate
that to changes in the brain and body
and trying to understand
what might be happening in a situation
where the brain and body have to work together
to create our sense of self.
Now, let me give you a couple of examples
We won't have time to go through all eight,
but maybe just by looking at a few you
can get a sense for what,
how this approach helps us understand
the nature of the human self.
Now, Alzheimer's disease, unfortunately a lot of us
will be familiar with because we will know
someone who is actually suffering from it.
This is quite a relentless neurodegenerative disease
that starts by affecting short-term memory formation.
So people start forgetting things
that have just happened to them.
And eventually it causes complete cognitive decline.
People are unable to, you know,
know anything about who they are.
They forget to recognize their loved ones,
some people who are very near and dear to them.
And eventually they're unable to take care
of themselves and have to be taken care of.
Now, this is quite,
this is an extremely debilitating condition.
And when you talk to caregivers
who are looking after people,
especially with end stage Alzheimer's,
they will say things like I don't think
the person I knew is there anymore.
And this is a very common refrain.
They'll say that person is gone.
The person I knew is gone. There is no one in there.
And so the question is,
what really is happening in Alzheimer's?
When you think about the first early stages of Alzheimer's,
when you're losing short-term memory formation,
what this is doing in the beginning is impacting
what can be called our narrative or autobiographical self.
So, if I were to ask any of you, "Who are you?"
you'll most likely give an answer
that is going to be a narrative.
You're going to say, I was born here.
I moved from New York to Madison.
Maybe you did; maybe you didn't.
Just as an example.
You'll probably talk about your children,
the work you do.
Essentially, you'll tell a story about who you are,
and that's the story we all have in our heads.
It's a story about how we think about ourselves,
about how we feel about ourselves,
and when someone asks us who we are,
that's the kind of response you will tell them.
You're very unlikely to tell them,
"Oh, I'm a bodily self, sitting in a chair,
"feeling my sensations."
You're actually going to tell them about a story.
So, in a sense, already you can see that
when you talk about the human sense of self
you can talk of two different aspects.
One is the autobiographical self, the narrative self.
The stories in our heads.
The story.
Or something very physical and bodily.
And we usually don't refer to the bodily self
when we're describing people and telling people
about who we are.
So, in the case of Alzheimer's,
what this does is it starts eating away
at the narrative self.
So think about what happens.
You have short-term memory loss.
You can't remember what just happened.
And obviously if something
is not going into short-term memory,
it's also not going into long-term memory.
And when you think about the story that you are,
when you think about who you are
in terms of the episodes in your life,
all of that is memory.
All of that is episodic long-term memory
that's stored somewhere in your brain.
We don't exactly know how that works,
but it's there in us.
And in order to have an autobiographical self
or a narrative self, your memory systems,
your ability to recall and sort of reenact those memories,
all of that should be intact.
And when short-term memory formation stops,
one of the things Alzheimer's does is it basically
puts a stop to the formation of the narrative self.
So, in some sense, when the disease onset begins,
the story that you are stops forming.
So that's the beginning stages.
And, unfortunately, as the disease progresses,
it starts eating away at old memories.
It starts going in and scrambling the order
in which you can tell your story.
So, for instance, there is a person
that I write about in my book where
when he was in the middle stages of his Alzheimer's disease
and when I would ask him about his life,
he would pretty lucid.
He would be able to tell you a whole range of things
that had happened to him,
but if you didn't know his real story,
you wouldn't be able to tell that the order
in which he was remembering things was all scrambled up.
So, in some sense, Alzheimer's has gone into
his narrative self and somehow ended up
just scrambling the sequence in
which one remembers who one is.
So, middle stages basically starts scrambling
and destroying the narrative.
Eventually it completely obliterates the narrative self.
And Alzheimer's poses a very interesting
challenge to philosophers.
Like philosophers,
there are some philosophers who have argued
that our self is just a story in our heads.
In some sense, it's because we have the ability
to be a story or be many stories and we have the ability
to tell stories about ourselves,
that is why we have the feeling of being an I.
Take away the stories and there is no I.
That's the philosophical argument that has been made.
Alzheimer's challenges that because we,
you know, if you actually are with someone
who has lost all narrative,
basically has no story to tell because their brain now
cannot recollect all those memories that formed them.
Does it mean that there is still no one in there
who is capable of experiencing pain or hunger
or any of the bodily sensations that we all take for granted
to be happening to one's self?
So basically the question is,
even though they don't have a narrative
or they don't have a story about who they are,
does it mean that their other experiences just
of being a physical body are unowned,
that no one owns those experiences?
It's a question that unfortunately we cannot answer
with Alzheimer's because someone with end stage Alzheimer's
is unable to communicate
what it must be like to be without a narrative.
But more and more scientists,
and social scientists especially,
are beginning to argue that no,
just because the narrative is gone doesn't mean
that there is no one in there capable of experiencing pain
or hunger or all the other emotions
that we have as happening to someone.
Even though that someone is not the full person
that we normally think of.
And Alzheimer's also challenges another view of the self,
which is that the narrative self, philosophers again argue
that it's just a cognitive thing,
that it involves just the brain consciously
recalling various memories that make us up.
So when we tell a story, we have to actually think about
who we are and narrate that story.
And, of course, that ability is getting
impacted in Alzheimer's.
There's no doubt about that.
But what's very interesting is that even in people
who have lost the ability to cognitively tell a story
about themselves, there is a lot of
their narrative self left in their bodies.
When I say body, I'm always,
remember that the body and brain are always working together.
So it's not like the body is separate from the brain
or the brain is separate from the body,
but there are things that we learn
and we become and which become part of our narrative
that are not necessarily recalled consciously.
That it's an ability that is there
within the brain/body complex.
For instance, there's an example
of the American composer Aaron Copland.
He suffered from Alzheimer's,
and towards the end of his days he,
if you left him at the, you know,
at some street corner, he wouldn't know where he was.
Put him in front of his orchestra.
He could conduct his, you know,
his signature orchestral suite, the Appalachian Spring.
I mean that memory, that ability of what he was,
was there in his brain/body complex,
but it was not open for conscious recall.
So there is something about our narrative being embodied.
It's basically part of who we are.
If you learn to ride a bicycle when you were four,
now that is also part of your story even though
you may not tell someone, Oh, I can ride a bicycle.
Of course you can tell someone, I can ride a bicycle.
But, actually, there might come a time
when we're unable to tell someone,
I can ride a bicycle, but you could ride a bicycle.
So, in some sense, that ability is embodied,
and it's still part of your narrative
So, again, Alzheimer's is challenging philosophers
and neuroscientists about the nature of the self.
It's not purely a cognitive narrative self.
It has embodied elements to it,
and it's not at all clear if both the embodied
and cognitive narrative aspects of ourselves go away.
Whether there is still someone or something
still left experiencing various perceptions.
So, this brings us to,
like we just mentioned the bodily self earlier a little bit.
This experience of just being a body.
Again, we take this for granted.
We take the experience of being a body for granted.
If you were to look at your arms and limbs
or just think about your arms and limbs right now,
you would have no doubt that they are yours.
Again, this is, you know, completely natural.
But it turns out that there are situations in which
the perception of your body can be altered.
And most of you will be familiar with the notion
of phantom limbs.
If somebody has had an amputation, for instance,
because of an accident or an injury or infection,
a lot of people after an amputation will continue
to feel the presence of their limb.
And these are called phantom limbs.
And some of them will even feel pain
in this nonexistent limb,
and that pain is called phantom pain.
Now, it's very, very clear in that context,
and this is indisputable.
This is something that's been shown over and over again,
and you can talk to people who have had amputations
and many of them will tell you that,
at least for a certain amount of time after the amputation,
they continued to feel the limb as if it exists.
And for some, that perception continues long
after the amputation.
It's very clear that what they're perceiving
is not the physical limb because the physical limb is gone.
What are they perceiving?
It turns out that one neuroscientific explanation
for what might be happening is that the brain
actually creates maps of our own body.
In order for the brain to control the body,
which is the brain's primary task is to basically
make sure that the body is fit for survival,
it creates maps, various kinds of maps of the body.
And what we perceive as our body
is actually the information content in those maps.
So when you've had an amputation,
the physical limb is gone,
but somehow the map in the brain has not got reorganized
and you continue feeling that limb
because that information persists in your brain.
So this is one way of showing that your bodily self
is actually something not really that solid.
It's basically information in your brain
that needs to be kept up to date
with the actual physical body.
And this condition that I write about,
body integrity identity disorder,
is the opposite of phantom limbs.
So, phantom limbs, one neuropsychologist called it animation
without incarnation, where, basically,
the physical limb is not there, it's not incarnated,
but it's animated in your mind
because you can feel the limb.
BIID is the opposite,
where it's incarnation without animation.
Where your limb is there, it's fine,
it's physiologically healthy and there's nothing wrong
with it in any normal sense of the word,
but for the person experiencing this condition,
they will feel as if that limb is not theirs.
So, in some sense, something about the map
of the information in your brain about your limb
is mismatched with your actual physical body part.
Now, what,
from the point of view of trying to understand the self,
what this forces us to ask is, "Am I my body parts?"
Think about it, right?
Here is a condition in which there is an I,
a person who can say, "I don't feel like this hand is mine."
Similarly, we can have another person saying,
"I feel like this hand is mine."
There is still an I.
There is still an I behind both those statements
making this, you know,
making a claim about some experience of being a self.
Now, what this tells you is that the I that is experiencing
either ownership of a body part or the non-ownership
of a body part is still something different
from the body parts.
So you can almost say, just like the poem I showed you,
"I'm not my body, I'm not my mind, I'm not my intellect."
This is saying, "I," whatever that I is,
we don't know that yet,
"I am not my body parts."
That I is capable of experiencing even non-ownership
or ownership of body parts.
Similarly, when we looked at Alzheimer's,
you can argue that I am not my narrative because,
like someone with middle stage Alzheimer's,
before Alzheimer's struck that unfortunate person,
he or she would have said, "I am my narrative."
But during the course of the disease,
suddenly the same person can be a scrambled narrative.
There is an I.
They're still experiencing a narrative that is scrambled,
and potentially experiencing a narrative
that is completely gone.
We don't know the answer to that yet
because we can't talk to people who have end stage Alzheimer's
and get clear answers about what it must be like
because the condition is so debilitating.
But, again, it kind of tells you that the I that experiences
being a narrative or not being a narrative
is slightly different from the narrative itself.
Similarly, the I here is different from the body parts.
There is still an I.
And I'll have to rush through the various conditions here,
but just to give you an idea that each of these conditions
changes something about our sense of self.
We can start asking similar questions.
Am I my thoughts?
Am I the agent of my actions?
So in schizophrenia, for instance, people can experience
having thoughts in their heads
that don't feel like their own.
Obviously it's their own thoughts,
but it feels like it's not their own.
And they can feel like they're not
the agents of their actions.
So if I were to lift this bottle of water,
I have an implicit sensation that I am lifting
this bottle of water.
And if you were unfortunately suffering
from schizophrenia, you may lift the bottle of water
and you may feel that, oh, this is not me doing it.
So it's basically telling you that even the sense of agency
that you have, that I am the agent of my actions,
which, again, we take for granted as being part of myself,
is slightly different from the I.
There is an I that can experience either being the agent
of an action or there is an I that can experience
not being the agent of an action.
Who or what is that I?
It's the same thing for thoughts.
We all have thoughts in our heads, and, again,
it's an unquestioned feeling we have
that they are our thoughts.
Each one of us thinks something inside
and feels like it's my thought.
What about the situation where you can have
a thought in your head and it feels like it's not mine?
Again, there is an I that experiences both feeling like
a thought is mine and a thought is not mine.
So I am not my thoughts in that context,
in that way of analyzing what the I is.
And you can go on like this.
Depersonalization disorder estranges people
from their own emotions, from their own bodily self.
So they feel their own body states
and their own emotions much less vividly
and feel a certain kind of distance from those things.
So, again, depersonalization disorder is telling us that I,
again I'm not saying what that I is,
it says whatever that I is, it's not emotions because
the I here is just a subject of an experience,
whatever that experience might be.
Sometimes experiences are feeling all your emotions
really vividly, and sometimes,
as in the case of depersonalization,
it is being disconnected from those emotions.
But that I still persists.
What is that I?
Autism, again unfortunately a lot of us now
will be familiar with people who are suffering from autism,
especially very young children,
and in its serious form can be very debilitating.
One of the things that happens in autism is children
with autism are unable to relate socially really well
with other children.
And philosophers also, again, have long argued,
not all but some, have argued that the experience
of being a self is fundamentally a social phenomenon.
That if you interact with others
and if you have relationships with others,
it's the social self that is at the core of being an I.
I think autism challenges that because,
you know, it would be very hard for a parent
to look at their child who has autism
and who is unfortunately unable to relate socially and say,
Oh, there is no self there.
Of course there is a self.
It's just a slightly different way
of experiencing social reality.
So there is still an I that is experiencing either
social relatedness or experiencing
or is having difficulty relating socially.
So whatever the social self is, there is still
an I experiencing it.
Whether it's, you know, what would be called
neurotypical or whether it's a child with autism.
So, who or what is that I?
Again the question persists.
Am I my body?
We just talked about body parts,
but you can ask the same question about your entire body.
Now, all of us right now hopefully
are having an in-body experience,
which means we are all here in our body.
But when you have an out-of-body experience,
you can have something called a doppelganger effect,
where you have,
and these are not paranormal experiences.
Science has very clearly shown that these are things
that are happening because of the way our brains
are misfiring or something is going organically wrong
with the way the brain is integrating information.
But you can have a doppelganger experience
where you can see a duplicate of your own self
in front of you and interact with that self.
So, normally, what does in-body mean?
In-body means I feel like I am, like I mentioned earlier,
I occupy a certain volume of space that is my body.
We all have that feeling.
I have a sense of ownership about my own body.
You know, again, it's implicit. It's unquestioned.
I feel like this body is mine,
and I also have a perspective.
I am looking out at the world and having
a sense that everything that I'm perceiving
is from behind my head and that it's all happening to me.
And that is the experience of being in-body.
It turns out when you have an out-of-body experience
aspects of these various traits get changed.
So in a classic out-of-body experience you can have
the sensation that you, whatever that I is,
has left the body and is looking down at the body.
The body appears lifeless, on the bed, and someone will say,
I am looking down at my body from the ceiling.
This has been replicated in, you know, in labs.
You can stimulate certain parts of the brain
and recreate these experiences.
So it's not paranormal.
It's not like something is really leaving your body.
It's, basically, some kind of integration
that the brain has to do.
You know, if you think about what the brain is doing,
it's collecting sensations from outside the body.
So there's sight, sound,
all the five senses that are giving the brain information.
There's also a lot of information coming
to the brain from within the body.
From our viscera, about the temperature of the body,
about blood pressure, all sorts of things.
And all of those things the brain has to integrate
and somehow create this experience of being in-body.
And if you mess with that experience,
and you can do that in the lab,
you will create variations of these out-of-body experiences.
So, again, by looking at what happens
when you're out-of-body,
you can start understanding how the brain
might create the experience of being in-body.
Ecstatic epilepsy, this is one form of epilepsy which,
if people are suffering only from this kind of epilepsy,
they will most likely not go to the doctor
because it's such a pleasant experience.
It's called ecstatic epilepsy because
they have feelings of bliss
and mental well being when the seizure is happening.
They have a very heightened sense
of their own body and the environment around them.
They have a feeling that time is slowing down.
The seizure might last one or two seconds,
but it feels to them like an hour has gone by.
They have no sense of time.
They have a very strong sense of certainty
about everything in the room.
I remember one person I talked to who used to have
these seizures, he at that time was a student in Kalamazoo,
and he said when the seizure happened
everything about Kalamazoo seemed so perfect.
And I knew because I lived in Kalamazoo
that it couldn't be so.
(laughter)
But when the seizure was happening, he was,
it was like divine order.
And also, paradoxically,
they have a sensation of being one with something larger,
some boundary between their self
and the outside has blurred,
even though they're feeling their own body
and the environment very, very vividly.
So ecstatic epilepsy is a condition that actually
also tells us a lot about how the brain creates
our sense of bodily self.
The feeling we all have of being a body,
sensing our body, our emotional state.
So, you can see that by looking at the way
in which the self gets disturbed in these conditions,
you actually start learning a lot about
how we are what we are.
I finally want to come to the most intriguing condition,
which is called Cotard syndrome.
Now, again, just like we all have an implicit feeling
that are in-body, that we right now are in our bodies,
that we own our bodies, etc,
I hope we all feel that we exist.
None of us, hopefully, will stand up here and say,
"I don't exist."
But as it happens, there is a condition,
which is called Cotard syndrome,
where the primary symptom is the person saying,
"I am dead," or "I don't exist."
It's obviously a hallucination.
It's a delusion, but it's a delusion
that you cannot convincingly
argue with them about.
They are convinced that they don't exist.
Now, and there are studies beginning to happen
that are telling us about why
this delusion might come about.
But, basically, by studying something
like Cotard syndrome, which is so stark,
I mean, here's an obviously alive individual functioning
in every sense of the word as an alive person would.
Of course, they are depressed
and they have psychiatric problems,
but you would not say that they don't exist.
But the person will insist that he or she is dead.
They will even do things like plan their own funeral,
or there's one person I write about who used to spend time
in graveyards because he felt more akin to people
who were dead than he felt with people who were alive.
And there's also a very sweet anecdote about him.
When he was put in the brain scanner to figure out
what was happening in his brain,
he came out of the scanner and the PhD student
who was working with him at the time in Belgium,
she said, "Are you alive and kicking?"
And he said, "Kicking."
He would not accept that he was alive.
And, again, this challenges philosophers.
You know, here is, again, a situation where you can say,
"I exist," or "I don't exist."
So, in some sense, existence and nonexistence
just become properties of the self.
The self is still something even more basic.
There is an I that can claim to exist,
or there is an I that can claim not to exist.
What is that I?
And that, in a sense,
is what philosophers are worried about.
So, essentially, what philosophers
are struggling to explain,
what neuroscientists are struggling to explain is,
where does this sense of an I come from?
By I, I just mean the sense
of being the subject of an experience.
It doesn't matter what that experience is.
It could be the experience of existing.
It could be the experience of not existing.
It could be the experience of having a narrative.
It could be the experience of not having a narrative.
There is an I that can experience just about anything.
What is that I?
How does the brain produce that,
if indeed it is the brain producing it?
How does it come about?
So, when you read philosophers arguing about the self,
whether there is a self or no self and whether the self
is an illusion or not, this is what they're arguing about.
They're arguing about whether the I is something
that is just a feeling that appears
because of all the other things the brain is doing
or because there is something in the brain
that actually is responsible for generating this I,
and then everything else happens to that I.
And bundled here is like I pointed out earlier,
David Hume, a lot of the Buddhist philosophy,
will fall under this notion that there is no I.
That the I is just something appears to be
so because of all the perceptions that we are having.
You take away all those perceptions
and it all falls apart and there is no I
at the center of it.
But there are others who will disagree.
There are self theorists who will say,
no, it's impossible to have this kind of unity of experience
if there wasn't something that the brain and body
were doing together in order to create a very, very minimal
self to which everything else can be referred,
to which becomes the subject of all your experiences.
And then there are others who will argue that the self,
the subject of an experience,
is nothing but consciousness itself.
And there we hit a wall.
No one knows what, you know, how to,
you know, what consciousness is.
They have trouble defining what consciousness is.
Neuroscientists debate among themselves
whether science will ever adequately explain
the nature of consciousness.
Philosophers disagree.
So it's a minefield, but it's interesting
that even the question of the self
eventually comes down somewhere
to saying we need to understand consciousness
in order to say what that I is.
And so for all the talk you will hear about illusions
and whether there's a self or no self,
I think it's fair to say that the debate is still open.
That there is something that is still unexplained,
and that is the nature of the I.
And I'll leave you there for now.
That's the book.
(applause)