Ep102 "Could you ever know what it’s like to be someone else?" (Part 1)

What does it mean to stand in another’s shoes—and when are the gaps between us too wide to cross? This week, Eagleman explores bats, kicked robots, Helen Keller, empathy, storytelling, and the phrase “I know exactly how you feel.” We'll weave through neuroscience, philosophy, literature, and technology to ask: Can we ever truly understand another’s inner world?

Episode Transcript

Speaker 1 (00:05):
Could you ever know what it's like to be someone else?
What does this have to do with bats? Or empathy
or bomb robots or Helen Keller or literature or when
someone says I know exactly how you feel. Welcome to

(00:25):
inner cosmos with me, David Eagelman. I'm a neuroscientist and
an author at Stanford and in these episodes we sail
deeply into our three pound universe to understand why and
how our lives look the way they do. Today's episode

(00:55):
is about the question of whether we can ever really
know what it's like to be someone else? Why are
we all so different? And is it possible that those
gaps are unbridgable. We'll examine this from the point of
view of neuroscience and philosophy and literature, and then technology.

(01:16):
Can new tech ever allow us to better understand what
it is to be someone else? Or is there an
inherent impossibility? So let's start with a simple question, what
is it like to be a bat? Now? This is
an interesting question because bats are so different from us.

(01:39):
They are mammals like us, but in many ways their
lives are unrecognizably foreign to our own. They sleep upside down,
but more importantly, they navigate through their dark caverns by
emitting little shrieks, and then their extremely sensitive ears pick
up on the echoes from that, and they figure out

(01:59):
the dimensional structure of the world in which they're flying.
And they can do this with terrific resolutions, such that
they can catch a flying moth just with this echolocation
in the pitch black. So in nineteen seventy four, the
philosopher Thomas Nagel wrote an essay by this title, What
Is It Like To Be a Bat? And it quickly

(02:22):
became one of the most famous thought experiments in modern philosophy,
because it challenges something fundamental about one of our intuitions.
He suggested that no matter how much we study another
being's brain or behavior or sensory experiences, we can't ever
truly grasp what their subjective experience feels like from the inside.

(02:48):
Nagel used the bat as his example, because seeing the
world through echolocation is a perfectly good sensory solution, but
it's totally foreign to cited humans. His point was that
we can study the process of echolocation scientifically, and we
can analyze how it works, and we can simulate it

(03:08):
with machines, and we can measure how a bat's brain
responds to these signals, but we can't feel it. We
can't step inside a bat's world and know what it
is like to move through space by sound. We can
understand it intellectually, but not experientially. And that brings us

(03:30):
to the question of this episode and the next one.
Can you ever truly know what it is like to
be something else, like another creature? But more importantly, can
you ever really know what it's like to be another person?
Not just sympathize with them, but really inhabit their world
from the inside out, know what it's like to be them.

(03:57):
When we're children, we think this is self. It's evidently
true that everyone is like us on the inside. But
as we get older, we recognize more and more differences,
and the question becomes more nuanced, because, as I've talked
about on many episodes, people can be very different from
one to the next on the inside. So we're gonna
dive deep into that and what it means. But first

(04:19):
let's get back to Nagel and bats to set the table.
Nagel's proposal was that there's something about subjective experience that's
just not accessible from the outside. So essentially, he said, look,
even if we had the most detailed scientific account of
the mental processes in the bat, even if we could

(04:39):
write down every neuron in the bat's brain and exactly
what the activity is doing, and even point to the
genes involved, and we could model the way that echolocation
works and simulate the bat's behavior perfectly, still we wouldn't
have answered the question what it is like to be
that bat? And this is the problem of the subjective

(05:01):
character of experience. It's not about behavior or function or
brain states. It's about what it feels like to be
a conscious creature, and that what it feels like quality.
This is what we call qualitia, the internal experience of something. Now,
qualia turn out to be really tough for science. Why

(05:23):
because science aims for objectivity. It tries to strip away
individual perspectives so that we can find truths that are
universally valid. But conscious experience just doesn't cooperate with that.
Consciousness is defined by perspective. It's the one thing that

(05:44):
can't be fully described in third person terms. There's no
outside view of the inside experience. So Nagel pointed to
bats simply because their sensory world is so different from
ours that it forces us to confront the limits of
our imagination. We can imagine what it would be like

(06:07):
for us to behave like a bat. We can imagine
hanging upside down, or eating insects, or maybe even using
sonar as a tool. But that's not what he's asking.
He's asking what is it like for the bat to
be the bat? And that he says is something we'll
never know, not even in principle. And this reminds us

(06:28):
that knowledge comes in different forms. There's the kind of
knowledge we can write down and measure and test, and
then there's the kind that lives only in the first person,
in the me in the subjective point of view. And
that second kind, that inner experience, isn't something we can
share or translate fully, even with the best science. So

(06:54):
this returns us to the question, can you ever truly
know what it's like to be another person? Even when
we're talking about someone we know intimately, we're up against
a wall because experience is totally private. And maybe this
is not just a philosophical or scientific challenge. Maybe this
is a human challenge, because no matter how we try,

(07:16):
there is a part of every person, every mind that
is forever out of reach. So let's zoom out for
a minute to make clear how much difference there is
between everyone's experience in the world. So let me start
with just a simple personal example. Many years ago, during
my postdoctoral fellowship, I dated a young woman and even
though she was often quite sad inside, she had a

(07:39):
very stunning Hollywood smile that she would paste on and
it would light up the room every time she did. So.
One day we went into a restaurant together and we
had to get to the back, but it was packed,
so we had to wind our way through a crowded
maze of tables to get to the back, and the
only way we could squeeze through was with me scooching

(08:00):
in right behind her, And because I was taller than
she was, I could see over her head as we
wound our way through, So she was the front guard
and I was mostly hidden behind her, and what I
saw was like a VR experience. Suddenly I was seeing
the world through a different set of eyes because she

(08:21):
had turned on her smile, and as we wound through
the crowd, everyone looked up at her and smiled back
and moved their chairs out of the way. It's not
that people weren't normally perfectly nice to me alone as well,
but there was a noticeable difference here. It was like
I was wearing the costume of someone else, and I
saw the world through her eyes and how people looked

(08:43):
at her and reacted to her. I saw how she
experienced the social realm. Now that told me something about
her experience of the world, But still the question remains
about her experience on the inside. What is that like
to her? We can extrapolate make some guess is but
how accurate are we? Of course? Lots of people experience

(09:04):
the world differently. Take height. What would it be like
if you were looking up at people at a cocktail
party because you were quite short? Or what's it like
if you're looking down on people because you're quite tall?
Does that change your social experience of the world. What
would it be like if you had much stronger arms
or legs and could do things yourself that you thought

(09:25):
you couldn't, or vice versa. What if you were the
opposite gender or looked very different than you do now?
There are a thousand little ways in which the body
that you're trapped in subtly changes your experience in the world.
But again, that's just the starting point for your internal life.
And if you've been listening to this podcast for a while,

(09:47):
you know that one of my main interests is about
the differences in our internal lives. The world looks and
sounds and feels a bit different to you than the
person sitting next to you. Many of my episodes have
explored this question the astonishing variety of internal experiences that

(10:07):
people have. For example, take synesthesia. Some people will look
at letters or numbers on a page and that will
trigger an experience of color, or that listen to music
and that will trigger swirling visual forms, or they'll taste
something and that'll put a feeling on their fingertips. This

(10:27):
isn't metaphorical stuff. This is a real experience that a
fraction of the population has. Their senses are crosswired in
a way that makes their inner world different from someone else's.
If you're interested in synesthesia, I talk about that at
length in episode four, or you've heard me talk about
other ways in which we might see things in our imagination.

(10:51):
One example of this is the spectrum from hyperfantasia to
a fantasia, which I talk about in episode fifty nine
or hyperfantasic, you visualize things with great clarity, almost like
a movie. If you are a fantasic, you don't form
any mental images. Let's say I ask you to imagine

(11:12):
a yellow dog running in a shallow creek in the woods.
The hyperfantagic person visually imagines that with great detail, almost
like they're watching it. A fantagic person sees nothing, no dog,
no color, no visual sense of shape or motion. Everyone
in the population is spread somewhere along the spectrum and

(11:35):
having different experiences on the inside. And there are dozens
of things like this. I've previously talked about word aversion
in episode twenty six. Word aversion is the immediate emotional
disgust that some people feel when they hear particular words
like moist or tissue or slacks or panties or nugget.

(12:00):
For most people, these words are just vocabulary, but for
other people they trigger an immediate visceral response like discuss
or anxiety. The point is across the population, even something
as simple as how you experience a word can be
very different from one brain to another. When we start

(12:20):
looking for examples like these. In neuroscience, things like synesthesia
or a fantasia or word a version. We just find
more and more examples. The differences in people's internal worlds
are real, and they're measurable, as has been done by
my lab and dozens of others. And I'm attaching some
studies to the show notes, and these differences between people,

(12:43):
they're not just about preferences or histories or what we
pay attention to. It's about the raw feel of experience itself,
how we perceive the world, how we process it, how
we represent it internally. And the more we learn about
these differences, the more are humble we have to become,
because it turns out that what you think of as

(13:04):
being a normal human is just one point on a
vast spectrum of human minds. Now, this doesn't stop us

(13:30):
from trying to step into another person's shoes. And this
is the notion of empathy, which is something our brains
do automatically. Empathy is our brain's ability to simulate what
someone else is going through, and researchers typically divide this
into emotional empathy, which is your ability to share the

(13:50):
emotional experiences of someone else, and cognitive empathy, understanding the
other person's perspective or their mental state. Now, even though
empathy seems like just a feeling you experience, it's of course,
under the hood a biological algorithm. Now you may have
heard of mirror neurons, which are neurons that become active
when you perform some action and also when you see

(14:12):
someone else do that same action. I mention these because
many people erroneously think that the mirror neuron system is
the basis of empathy, but in fact, empathy involves much
more than that, because you also need a whole collection
of regions that integrate emotional information and social information and

(14:33):
tell you what are the really salient things to pay
attention to. So nowadays you can put together hundreds of
brain imaging studies fMRI to see that there's a whole
network of brain regions that come online when you're considering
the emotions of another person, regions like the anterior insula
and the anterior singulate cortex, and the amygdala and the

(14:56):
inferior frontal gyrus. Okay, the details don't matter for today's purpose,
except to say that all these areas consistently come online
during tasks that require you to simulate another person's state,
like if you see them experience pain or distress. Even
though you're not experiencing that, your brain runs the simulation. Now,

(15:19):
why do we have such a rich system for simulating
other people in our heads. It's because biologically, empathy is
not just a nice to have, it's a survival tool.
It helps us connect and cooperate and parent and navigate
the complexities of social life. And in that sense, it's
not just emotional intelligence we're talking about. It's neural engineering

(15:43):
evolved for living together in large groups. And this is
why we flinch when we see someone else in pain,
and also why laughter spreads so easily through a crowd.
It's because when we witness another person's emotional state, our
brains simulate it, creating a kind of inner echo of

(16:05):
what they're feeling. It's not the real thing, but it's
a rough sketch. And this capacity for empathy is very
useful for what's known as theory of mind, which I
talked about in episode seventy two. This is the cognitive
ability to understand that other people have thoughts and feelings
and perspectives different from yours. Little kids don't have theory

(16:29):
of mind, but it develops through early childhood and that
moment when a Toddler realizes that another mind is not
the same as theirs. This marks the beginning of perspective taking.
This is the foundation of social connection and storytelling and
even deception, because without theory of mind, you'd be stuck

(16:50):
in your own mental bubble. And by the way, having
good theory of mind is something we keep refining our
whole lives. Some people become especially fluent in it, especially
people like actors or therapists or even parents. Other people
struggle with theory of mind, not because they're cruel, but
because the skill of imagining someone else's internal world takes

(17:12):
practice and effort and humility and the right kind of
neural circuitry. So we are as species who tries to
model one another. We try to step into each other's shoes,
but we're really not so good at it. Mostly we
just assume that everyone else is like us on the inside.

(17:34):
When you really look at empathy, you can see that
what we're really doing is imposing our models on what
we think the other person is feeling. As a really
good example of this, I've noticed this with videos of
robots produced by a company called Boston Dynamics. You might
have seen these. They are these robots that look like

(17:55):
metal dogs, and one of the things the company wanted
to show is that these dogs are robust against being
knocked off course. So the robot dog is running forward
in the video and someone comes out and kicks it,
and the robot's legs do a quick scramble, and even
though it tilts to the side, it manages to stay
upright and it keeps going, which is very impressive. But

(18:17):
here's the thing. I've seen dozens of people watch these
videos and they WinCE. Their empathy is stoked. And I
get it. It looks like a creature, it looks like
a sentient being, and it's getting kicked. It's really difficult
to watch this and not feel an empathic sting. But
I think what this illustrates is our propensity to imagine

(18:42):
that other things feel the way we do, even when
there's really no good reason to imagine that we're looking
at anything other than a collection of nuts and bolts
and wires in the case of this robot. So, in
other words, our feelings of empathy are a massively important
part of our success as a species. Details presumably say
more about us than they do about the accuracy of

(19:06):
the feeling in other words, how much your assumptions about
the inner life of the other is right on target.
I'll give you another example of the weirdness of this
our responses to reading or watching fiction. One of the
classes I teach at Stanford is called Literature and the Brain,
and an issue I always talk about with amazement is

(19:27):
the fact that we shed tears, or we laugh out loud,
or we worry or we agonize over the pain of
somebody else, someone we know is not real. You're reading
about let's say John Snow in Game of Thrones, and
you're aware that the whole world he's in isn't even real.
The author can tell us, look, this is fiction. There

(19:48):
can be a giant sign in front of you that
says this is a string of words depicting a world
that is totally made up, And it won't stop tears
running down your cheek once something bad happens to John
snow Now. I'll come back to literature and empathy in
a moment, because I think literature is one of our
most important tools for expanding the fence lines of our empathy.

(20:11):
But for now, I'm just making the point that simply
because you feel that someone else must be feeling the
same thing you are. You might be talking about a
robot or an explicitly made up character, and you'll still
impose what you believe is this is what that person
must be feeling. And obviously it's not just with robots

(20:32):
or fictional characters. We empathize more with people we assume
are more like us, and that might not be accurate.
So in episode twenty, I talked about neuroimaging experiments in
my lab where we put people into the brain scanner
and we showed them six hands, and one of the
hands gets selected by the computer and you see that

(20:55):
hand get stabbed with a syringe needle. This activates a
net work in your brain that we summarize as the
pain matrix. And as I mentioned before, this is the
neural basis of empathy. You're having this fireworks show in
your brain light up, even though it wasn't your hand
that got stabbed. You're just watching someone else's hand, and

(21:15):
yet you are simulating the pain involved. But here's the
key thing. We then labeled each hand with a one
word label Christian, Jewish, Muslim, Scientologist, atheist, Hindu, and now
the computer picks the hands one at a time. And
you see them get stabbed with this syringe needle. And
the question is do you care as much if it's

(21:38):
any of the members of your out group versus the
label of your in group. So we studied one hundred
and five people on this and the answer was clear.
Your brain has a large empathic response when you see
the hand with your group label get stabbed, and it
just doesn't muster the same degree of response when it's

(22:00):
anyone else getting stabbed. And this was equally true across
all the groups, including the atheists, who cared more when
they saw the atheist hand get stabbed. So in earlier
episodes I talked all about the meaning of this from
a societal point of view, but for today I want
to emphasize that whatever your religion is or your non religion,
there are literally millions or billions of people who belong

(22:23):
to that label too with you, and they are all
as different as can be, and the spread is enormous,
And so the idea that you would care for those
millions of people more than other millions of people suggests
again that your empathy is not so much about climbing
into someone else's head, but instead about imposing your model

(22:46):
onto the external world. So whether that's for robots or
for John Snow or your group label, it really just
represents your internal world more than an actual bridge that
reaches a cross and connects with another. And this I
think illuminates an important facet of our human experience. We

(23:10):
started off with the question of whether you can ever
truly know what it's like to be someone else, And
on the surface, it seems like we do this all
the time. We empathize, we imagine, we say things like
I know exactly how you feel. But do we actually
when we say to someone that we know how they feel.
We mean it as a comfort, But sometimes it misses

(23:33):
the mark because even though two people can go through
something similar, the emotional landscape can be entirely different. Think
about somebody that you know really well, maybe your partner,
and think about some moment in their life that was
emotionally charged, some loss or some triumph. You might have
even been there, but did you experience it exactly as

(23:55):
they did, or is it possible there was something else
going on inside there in her cosmos? So here's an example.
A listener recently wrote into me about losing his father.
He described sitting at the hospital bedside, holding his father's hand,
feeling the warmth drain away. A friend of his, who

(24:16):
had also lost a parent, worked to comfort him by saying,
I know exactly how you feel. But instead of feeling seen,
he felt misunderstood, because in that moment, his grief was
raw and specific, tied to a lifetime of private memories
and smells and words and rituals. His friend's grief was

(24:38):
real too, but it wasn't the same. This is where
the question of understanding a bat or another person matters,
because we share space, we share language, but we can't
always share perspective. Even when we use the same words,
like grief or joy or fear, what those as words

(25:00):
refer to feels different inside of you and me and
everyone we know. As another example, you and I might
both bite into an orange and say it tastes sweet,
But your sweetness is not necessarily my sweetness. It's a
private event dressed up in public language. Now take that

(25:21):
idea and stretch it to more complex experiences. What is
it like to grow up in a war zone, to
live with chronic pain, to navigate the world in a
body or a mind that's profoundly different from yours? We
can ask questions, we can listen, we can learn, but
we also have to acknowledge that there is a hidden
interior to every life. And this is something that no

(25:45):
brain scan, no survey, no biology jargon is ever going
to fully capture. So probably the best thing to do
with a friend or loved one is not to assume
that you've been there too, but to be willing to say,
haven't been there, but I'm here with you now. Now

(26:17):
this whole episode so far, I've been emphasizing how poor
we are at expanding our models to know what it
is like to me someone else, Even among humans' experience
is just not fully shareable. Empathy isn't mind melding what
we have our approximations. These are efforts to close the gap,

(26:38):
but these aren't bridges that actually close it. And yet,
although we can never do it perfectly, we can get
better at it through life experience. And one of the
ways this can be magnified is through the reading of
literary fiction. There have been a number of studies showing
that reading literary fiction, especially complex character driven stories, can

(27:02):
improve people's abilities to understand other people's thoughts and emotions.
One study from twenty thirteen, published in the journal Science,
found that people who read even a short excerpt of
literary fiction scored better on tests of theory of mind
the ability to infer other people's beliefs and desires and emotions.

(27:24):
The comparison group, by the way, read nonfiction or popular
genre fiction. The idea is that good fiction asks you
to inhabit unfamiliar minds. You track subtle emotional shifts, you
decode social cues, you grapple with ambiguous motives. You're simulating

(27:47):
other people's minds, and you're getting concentrated practice at it.
What we find in the brain scanner is that when
you're reading, this engages the default mode network, which is
involved in self reflect and imagining other perspectives, and it
engages other areas that are tied to empathy and social reasoning.

(28:08):
So every time you get lost in a novel, you're
training your brain to be a little bit better at
knowing what it's like to be other people. President Barack
Obama did an interview with The New York Times in
twenty seventeen, and he said, I think that I found
myself better able to imagine what's going on in the

(28:29):
lives of people throughout my presidency because of not just
a specific novel, but the act of reading fiction. It
exercises those muscles, and I think that has been helpful.
End quote. This is what literature is good at. We
get to experience life from a different point of view.

(28:49):
And this can sometimes apply to nonfiction too. Take Helen Keller,
a woman who is deaf and blind. She wrote about
how her reality was shaped by the actile world of
touch and vibration, not by the vision and hearing that
most of us take for granted. When we read her,
we aren't accessing her world directly. We're just catching reflections

(29:12):
of it. But nonetheless it expands our otherwise naturally small
view of things. It exercises those muscles, and it makes
us cognitively broader. In the book To Kill a Mockingbird,
the character Atticus Finch says, quote, you never really understand
a person until you consider things from his point of view,

(29:34):
until you climb inside of his skin and walk around
in it. End quote. Now, as we've said, you're not
really walking around in their skin, but you can get
better at trying it. But I was thinking about that
idea of climbing inside someone's skin and walking around in it.
And this idea leads to one of the most intriguing
frontiers in empathy research today, which is virtual reality. Because

(29:58):
VR can tempt, imp rarely place you in someone else's shoes,
not metaphorically, but perceptually, and researchers have started to use
this as a way to see if they can enhance empathy.
So in one line of studies, people put on a
VR headset and they experienced life as a person from

(30:19):
a different background. So, for example, you can inhabit the
body of someone of a different race, or a different gender,
or different ability. You don't just look at them, You
look down and you see your body as theirs. You
move your hands and their hands move. It's an embodied simulation,
and these studies showed that it can measurably increase people's empathy.

(30:43):
A similar study comes from my colleagues at Stanford. You
put on VR goggles and you get to experience what
it's like to become homeless, to lose your home, your belongings,
your place in the world. So they run the VR
experience and then afterward people report greater concern for homelessness,
and they are significantly more likely to sign petitions for

(31:05):
housing initiatives. What makes virtual reality powerful in these studies
is that it bypasses the usual roots of reading or
listening or imagining, and instead it plugs into your perspective
at a sensory level. Your brain thinks, I know I'm
not this person, but it feels like I am, and
empathy begins to take root. So today's episode set the

(31:29):
table for something very important, which is the question of
the limits of our objective understanding. We began with Thomas
Nagel's question what is it like to be a bat?
Which illustrated the difficulty or maybe the impossibility, of ever
being able to answer that question, because even if we
can measure everything about the bat's neurons and firing patterns,

(31:52):
it doesn't tell us what it's like to be on
the inside to be the bat. And we then looked
at what this means for understand inning other people. We
all like to imagine that our empathy lets us step
into the shoes of another person, but as we see
from our empathic responses to robots or fictional characters, it's

(32:14):
not necessarily that we're having a mind to mind connection,
but instead empathy is an expression of our own internal
model you're imagining what the other person feels, but that
may or may not have much relation to the reality
of it. And the study I told you about with
the labeled hands getting stabbed with a syringe needle, it

(32:35):
turns out everyone cares more about their own in group
than whatever their outgroups are, and so that suggests that
empathy isn't even a terribly sophisticated model, but instead is
greatly swayed by whether people remind us of ourselves. So
when we're tempted to say I know exactly how you feel,

(32:56):
maybe we should pause, because what we really mean is
I can imagine my version of your experience, and that's
not necessarily the same thing, but maybe it's enough to
try to reach, even knowing that we're never going to
fully arrive, because while we can't fully be someone else,
the attempt to understand them, even knowing it's incomplete, can

(33:19):
still be helpful because the project of human connection isn't
actually about perfect simulation. It's about making room in our
minds for perspectives that will never fully grasp And this
leads to a little bit of hope because we can
get practice at expanding our fence lines, as seen in
the reading of literature and even experiencing other lives VR

(33:42):
This sort of exercise can provably expand our internal models,
at least a little bit, giving us a richer sense
of different people in different situations. Reading and experiencing it
makes our empathy a bit wider. But I want to
come back now to the question I started with, Could
you ever know what it is like to be someone else?

(34:05):
Today's episode suggests it's not so easy, But there's an
interesting question that struck me from the time I was
a kid, and the longer I've studied neuroscience, the more
the question seems relevant to me. Could technology ever allow
us to know what it's really like to be someone else?
Could we use new techniques or even techniques that will

(34:26):
exist in the distant future that would allow us to
change the firing patterns in our brains to make those
patterns like someone else. Could we do this with electrodes
or with nanobots or do we have old fashioned ways
of doing this with pharmacology that could shed light on this?
And what does this have to do with replaying someone

(34:47):
else's memories or a future with dreams? Celebrities who have
dreams that go viral or the idea of hooking two
brains directly together so people can experience each other's reas reality.
Want to know the answers, Please join me next week
for part two of Could You ever Really Know what
It's like to be someone else? I can't wait to

(35:10):
see you. Then go to eagleman dot com slash podcast
for more information and to find further reading. Send me
an email at podcasts at eagleman dot com with questions
or discussion. Join my substack at David Eigleman dot substack
dot com and check out and subscribe to Inner Cosmos
on YouTube for videos of each episode and to leave

(35:31):
comments Until next time. I'm David Eagleman and this is
Inner Cosmos.