[MUSIC PLAYING]
MARIO LIVIO: Thank
you very much, Mark.
So here is the time when
you see me a little bit.
And then I'm switching
to the slide.
So should I do that?
MARK: Go ahead.
MARIO LIVIO: So the book
is about human curiosity.
And the reason I wrote a
book about human curiosity,
even though I'm an
astrophysicist--
and not a neuroscientist
or a psychologist--
is because I am a very,
very curious person.
And at some point I became very,
very curious about curiosity.
So I decided to do
some research on this.
Read up on all the
research that has
been done-- by
cognitive scientists,
by neuroscientists--
on curiosity.
And what you see now
is the result of that.
So let me start with
something very strange here.
You see this abstract
painting in front of you.
But inside that abstract
thing, actually,
hides the question
mark which appears
on the cover of the book.
I start the book with a story.
A little story about
this writer, Kate Chopin,
who lived in the 19th century.
She lived most of her
life in Louisiana.
And she wrote a whole
collection of short stories,
and a few full-length novels.
And I found something very
interesting about her.
One of her short stories is
called "The Story of an Hour."
And this is truly a
very, very short story.
In fact, it is so short
that, as you can see here,
the whole story fits on less
than one page of "Vogue,"
from 1894.
And like I said, it's called
"The Story of an Hour."
This, by the way, shows her
husband, who was a Frenchman--
Oscar Chopin-- and the
house in which he lived.
This short story, "The
Story of an Hour,"
starts with a
startling sentence.
It reads, "Knowing that
Mrs. Mallard was afflicted
with heart trouble,
great care was
taken to break to her
as gently as possible
the news of her
husband's death."
One can hardly
start a short story
with a better
sentence than this.
You see, in one
sentence, she packs
both death and human frailty.
So if this doesn't
make you curious,
I don't know what will.
And this is her greatest gift.
What she's able to do, is
she is able to generate
these intellectual cliffhangers,
if you like, with almost
every sentence that she writes.
And that's why I
like that so much.
Now let's start to
talk about curiosity.
So there was this
psychologist, Daniel Berlyne--
he was a British Canadian.
And he wanted to put
curiosity on a grid,
like this, where he gave names
to various kinds of curiosity.
And the names used here are
perceptual and epistemic,
diversive and specific.
And I will explain what
each one of those means.
Now I must give a
small caveat here.
Psychology is not mathematics.
So, you know, when Descartes
put a grid like this,
he was able to generate
all of analytic geometry,
and all kinds of great
things in mathematics.
In this case, of course, this
particular classification
is not unique.
But it is still
fruitful, in the sense
that it helps us map
curiosity in these regions.
Now what are these different
types of curiosity?
So let's start with
the axis that goes
from perceptual to epistemic.
What is perceptual curiosity?
Perceptual curiosity
is the curiosity
we feel when we see
something surprising,
something that doesn't agree
with something we know or think
we know, something puzzling or
something it's an ambiguous.
That's perceptual curiosity.
Here is an example.
These Asian kids
see a white girl
for the first time
in their life.
Look at their faces.
I mean, they didn't even know
that such a thing exists,
before.
And, you know, they
all gather like this,
and they are very,
very curious about it.
Opposite perceptual curiosity
was epistemic curiosity.
Epistemic curiosity
is the curiosity
that drives all basic research.
It's what drives us
to ask why and how,
when we try to
understand something.
It is the real love of
knowledge that many of us have.
Again, here is an example
of epistemic curiosity.
These kids want to understand
how these plants grow.
You know, what makes
them grow, what
happens to them, and so on.
So that's one axis.
Then on the other axis
we had diverse curiosity
going to specific curiosity.
What is diversive curiosity?
You know, being
here at Google, I
have a feeling that many of
you have diversive curiosity.
That's expressed
by this thing here.
These kids there, they sit
next to one of the greatest
works of art in Western art.
This is Rembrandt's
"The Night Watch."
And look what they are doing.
They are all looking
at their phones.
This is diversive curiosity.
This is when you have constantly
to check for text messages,
or you wonder what will
the new iPhone look like,
or things of that nature.
Or Android, or whatever
what model of smartphone
you're talking about.
Finally there is--
opposite diversive,
there was specific curiosity.
This is when you
are actually curious
about a very particular
piece of information.
You know, like who was it
that created the first chip
for the first Android telephone,
or we saw this film last week,
what was the name of the actor
there, you know, and so on.
Like, for example,
here, who is this?
Does anybody know, by
any chance, who this is?
This is Ernest Hemingway.
Here, in 1918, he is in Milan.
So that's specific curiosity.
You need a very specific
piece of information,
you're given that
piece, and that's it.
You are satisfied with that.
Now before I start describing to
you the research on curiosity--
the neuroscientific and
psychological research--
I thought-- in the book I
decided to look at a few very,
very curious people--
both in the past and
people who are living--
and to analyze a little bit
what is it that drives them.
What is it that,
you know, made them
such exceptionally
curious individuals?
So the first one is
Leonardo da Vinci.
He has been called,
by art critic Kenneth
Clark, the most
relentlessly curious person
to have ever lived.
And, indeed, Leonardo
was amazing in many ways.
Of course he has
incredible works of art,
he has all kinds of very
interesting inventions
associated with his name,
but perhaps most amazing
are his notebooks.
These are two pages
from his notebooks.
There are, today,
about 6,000 pages
that remain from the collection
of about 15,000 pages
of notebooks that existed.
When you look at this,
it looks, at first,
like some collection
of unrelated doodles.
By the way, he
filled-- you know,
if you look at the period of
time which he wrote notebooks,
you discover that on the average
he had to fill out, every day,
at least a page and a half--
every day, in order to get
this amount of notebooks.
The notebooks always
contain drawings.
And they also contain writing,
which he always wrote--
he was left handed.
He wrote from right to
left, and in mirror image.
In order to read it, you
needed to put a mirror to it.
Now, you look at this,
and at first, you know,
you don't see much connection
between the things.
When you look a little
bit more carefully
you start to see two
main themes here.
One is a whole host of
geometrical curves, and then
certain phenomena.
And the phenomena include
waves in a pond, water,
there are clouds on the
right side of this image.
There is the hair of
this old gentleman
which looks almost like
the clouds, exactly,
and things like that.
Then there is the
phenomenon of branching.
You have this plant right
in the middle of the figure.
You have a tree right
underneath the old gentleman.
And you cannot
quite see it here,
but if you look up close at
this image, you will see that,
actually, the
branches of the tree,
they are transformed into
the veins of the old man,
seen through his coat.
So the two phenomena
here are curves--
and things related
to these curves--
and branching.
So this gives you a little
bit of an idea of how
his mind might have worked.
You see, he was very
visually inspired,
by things that look
in certain ways.
So let's say he
started studying, OK,
how do waves propagate from
a pebble thrown into a pond?
He looked at that,
and he said, aha,
there are some geometrical
curves associated with that.
Once he had those curves,
he started thinking,
but in what other phenomena
do I see curves like this?
And that led him, let's
say, to the clouds,
or to the hair of
this gentleman.
And, you know, if you
look at his drawings,
when he draws flows of water--
which is a phenomenon
he dealt with a lot--
then his drawings
of flows of water
look very much like
braids of hair.
And when you look at
these drawings of hair--
for example, the National
Gallery in Washington DC
has his painting
"Ginevra de Benci,"
you look at the hair at
the front of her face,
and it looks just
like turbulent water.
So he really connected
these things in his mind,
and thought about them together.
Now what was he interested in?
In everything.
You know, you look at the
collection of books he had--
at one point in
time, 106 books--
there is almost no topic that
he didn't have a book on.
There is one topic that he
really stayed completely off,
and that was politics.
And that was a very good idea,
because he lived at the time
when the Borgias reigned.
And the Borgias--
just everybody who
got involved in their politics
got more or less killed.
Leonardo, by staying
completely out of politics,
actually managed to have them
patron his works, and funding.
So he also was very,
very interested
in anatomy, of course.
And his interest in
this was very different
from that of almost
anybody at his time.
Because, you see,
the theory of anatomy
that was prevailing
then was done by Galen,
you know, in ancient Greece.
And everybody just
adhered to that.
And what they used to do--
even when they already
did dissection on corpses, and
so on, all they tried to do
is to prove that
Galen was right.
Leonardo, on the
other hand, he didn't
want to prove that
anybody was right.
He wanted to learn what's there.
So, for example, in the heart--
to which he spent more time
than to any other organ--
he discovered the
arteries of the heart--
which weren't known before him--
what their role was.
He discovered how heat
is generated in the body,
through the flow of the
blood, and things like that.
So he really he showed
this epistemic curiosity.
He tried to learn
by being so curious.
The second person I discuss in
the book is Richard Feynman.
Richard Feynman, of course,
is a legendary physicist.
There is almost no
branch in physics
to which he did not contribute.
But he also did work in biology.
He also was a drummer,
you know, on a bongo.
He actually went, even, to
Brazil to learn to drum.
He was interested in
Mayan hieroglyphs.
He was interested
in safe cracking.
And generally, he
basically had this notion
that everything is
interesting, if you
get into it deeply enough.
Now, at one point, Feynman
started to learn how to draw.
Because he said that there is
this beauty in nature, which
is a beauty not of the
type that, you know,
what normally painters do--
but a beauty in the
understanding of what nature
is all about.
And he wanted to be
able to draw this.
So he asked his friend
Zorthian, who was a painter,
to teach him how to draw.
And he actually tried
to teach him physics.
Wasn't particularly successful
in teaching the artist physics,
but he, himself,
became OK in drawing.
And I want to show you a
page from his notebook.
And this is a page from
Feynman's notebook.
And just look at this.
The mathematics is, of course,
more complex than it is
in Leonardo's.
And the drawing is
of lesser quality
than the drawings of Leonardo.
But other than that, I mean,
this could have been-- you
know, you could have
exchanged their notebooks.
They both were interested,
literally, in everything.
So you know, these
two people, of course,
come at the very extreme
edge of curiosity,
compared to almost
any other people.
Let's now get into the
research on curiosity.
So in 1994 psychologist
George Loewenstein,
from Carnegie Mellon
University, proposed
a model for curiosity, which
was called the information gap
model.
What was this model?
The idea was the following.
That when we see
something that does not
agree with our beliefs, or
what we know, or what we think
we know, a gap is formed.
It generates an adversive,
unpleasant state in our mind.
And that curiosity
is the mechanism
by which we try to get rid
of this unpleasantness,
by finding new information.
So curiosity, in the
information gap model,
is a little bit like an itch
that you have to scratch.
So you have an itch,
you have to scratch it--
that's what he says.
Now associated with this is
this inverted U-shaped curve
of curiosity as a
function of knowledge.
The idea is the following.
You see, the claim is-- and I
will show you that experiments
actually confirm this--
when we know about
something very, very little,
we're not curious about
it, because we don't
know what to be curious about.
When we know about it a lot, we
feel we know almost everything,
we're also not curious
about it, because, you know,
what we don't know
is very little,
and it's deemed unimportant.
When we get curious is at
the middle of this curve.
Namely, when we know
something about the subject,
but we also feel that there
is much more to be known.
That's when we become truly
curious about something.
Now believe it or not, but a
former Secretary of Defense
actually once-- without
knowing about curiosity,
or any such thing--
actually captured this idea
of this inverted U-curve.
This was Donald Rumsfeld, who
once had a press conference
in 2012, before the Iraq war.
He was asked at the
press conference, what
does he have to
say about the fact
that there is no evidence that
Iraq is transferring weapons
of mass destruction to
terrorist organizations?
And that was his answer--
[VIDEO PLAYBACK]
- There are known knowns--
there are things
we know we know.
We also know there
are known unknowns--
that is to say we know there
are some things we do not know.
But there are also
unknown unknowns--
the ones we don't
know we don't know.
[END PLAYBACK]
MARIO LIVIO: That was his
answer to that question.
Now there is a British
organization that, every year,
gives the Foot in
the Mouth Award
for somebody-- for some
statement they made.
They gave it to him that year,
for the most baffling statement
made by a politician.
And, by the way, the
runner up that year--
number two prize-- was
actually given to Arnold
Schwarzenegger--
former governor of this state--
who said, I think that
gay marriage is something
between a man and his wife.
[LAUGHTER]
So he got the second
prize for that.
Now what Rumsfeld said,
it's very funny as an answer
to a question about weapons
of mass destruction.
But actually, as a
statement, is actually
a very logical statement.
You see, there are
things we know we know,
there are things we
know we don't know,
and there are things we
don't know we don't know.
Now this actually captures
that curve of curiosity.
You see, when we
know we know, that's
when we think we
know everything,
and we're not curious anymore.
When it's unknown unknowns,
we're also not curious,
because we don't know
what to be curious about.
When are we curious?
When there are known unknowns.
When there are things we
know that we don't know,
that's when we become curious.
So oddly enough, this
bizarre statement--
which is, however, logical--
actually captures that thing.
Now experiments
actually confirmed
the idea that, at least
for perceptual curiosity--
I remind you,
that's the curiosity
you feel when there is something
puzzling or ambiguous--
then it is actually associated
with an unpleasant feeling,
and it also activates
those regions in the brain.
How do they do that?
How can neuroscientists
do these experiments?
So what they do today--
I mean, they have tools
that once were not
available to them--
they can do functional MRI.
Namely, they can put
people inside MRI machines,
and can try to
make them curious,
and to see which regions of
their brains are activated.
Now these are not
easy experiments,
because you cannot take somebody
and tell them, be curious now.
You know, that's not possible.
So what they do is, for example,
in this particular experiment--
conducted by Marieke Jepma,
a Dutch neuroscientist--
is that they showed people this
collection of images, where
they first show them
a blurred image,
and then they show
them clear images,
sometimes of the same object,
like the accordion here.
They show a blurred
image of an accordion.
They ask people what, do they
think that is, and so on,
try to make them
curious about that.
And then they show them
the real accordion.
Now, in order to confuse them,
so that people don't always
expect the same
thing, sometimes they
show them a blurred imagine
and a clear image of something
completely different,
and things like this.
Like, you see, they
show something there,
and then they show this
tiger, which are unrelated--
and things of that nature.
But what they found
was that indeed,
for the case of
perceptual curiosity,
the regions in our
brain that are activated
are those that are
associated with conflict--
with hunger, with
thirst, things like that.
So it's like a basic need.
It's an unpleasant situation.
So for perceptual curiosity,
the information gap model
actually works quite well.
And it also shows this
inverted U-shaped curve.
Now what about
epistemic curiosity?
I remind you, that's the
true love of knowledge.
The thing that drives us to be
scientists, things like that.
So there is another experiment
done by a researcher named
Kang, and her collaborators.
And what they did
in this case, is
they presented the subjects with
a series of trivia questions.
I remind you, this is--
we're testing, now, the love
of knowledge, the wanting
to learn, things of that nature.
So they presented them
with trivia questions,
such as, I don't know--
which musical instrument
was invented so as
to sound like a human voice?
OK, do you know what that is?
The violin, yeah.
So questions like this.
And they also checked
how curious people
were about this, and so on.
And they discovered that
in this case, actually,
curiosity was associated
with a pleasurable state.
And this actually
has been suggested
by another psychologist
named Spielberger.
That when we want to learn
something, that's associated
with a pleasurable state.
And indeed, the
areas of the brain
that were activated by
this type of curiosity
were those associated with
an anticipation of a reward.
Of a reward.
Namely, our brains interpret
the acquisition of knowledge
as a reward.
It's a bit like when
we get chocolate,
or when we get drugs,
or we win the lottery,
or things like that.
An anticipation of reward.
When you sit in a theater in a
play you always wanted to see,
and you wait for the curtain
to go up-- things like that.
So in other words, in terms of
these two types of curiosity,
not only are they associated
with different states of mind.
Namely, perceptual
curiosity-- this surprised
ambiguous stimuli, and so
on, is an unpleasant state,
an aversive state.
And it also triggers regions in
the brain that are associated
with such states.
In the case of
epistemic curiosity,
this love of knowledge,
this is a pleasurable state,
an anticipation of reward--
and it triggers areas
in the brain that are
associated with such rewards.
Now all of these experiments
that I've described so far
are done with adults.
In fact, you may know--
or you may not know--
that most experiments
in psychology,
until fairly recently, were
done with either freshmen
or sophomore students.
So there were some
people that jokingly
used to say that, in fact,
all the results in psychology
only apply to that
demographic, because all
the experiments were done
with those type of people.
But in recent, already,
couple of decades,
people started doing experiments
with very small children, even.
Very, very small children.
So I want to describe to
you an experiment here
that was done at MIT.
And the idea is the following.
There is a very small child.
And the child is shown
a particular toy.
And when the researcher
presses a button on the toy,
the toy makes a certain noise.
And then you will see
what happens after that.
[VIDEO PLAYBACK]
- 2, 3, go.
MARIO LIVIO: So she
now presses the button,
and it makes a noise.
- Wow!
MARIO LIVIO: So look, the
child already wants it.
Already wants that toy.
- --2, 3, go.
MARIO LIVIO: She presses
the button again.
Again, the noise.
- Wow, that's pretty cool, huh?
MARIO LIVIO: Now the
researcher shows the child
that she has two other
things that look similar,
of different color.
She puts one there, and
she gives the green toy
to the child.
The child immediately
tries to press it,
and it doesn't make the noise.
So look what the child does--
turns to his or her parent.
Because she thinks--
or he thinks--
maybe I'm doing
something wrong here.
Now she's giving the
child the yellow toy,
which looks a bit different, but
still has something that looks
a bit like the previous button.
So look, she will try--
or he will try--
to press it, but
nothing happened.
Now, she says, ah,
maybe it's broken.
So she bangs it, you see.
But now she sees
the red toy, that's
there on that piece of cloth.
So look what she
does-- or he does.
Look, pop, and gets that.
[END PLAYBACK]
So this very small child
was able, first of all,
to understand
confounded evidence--
namely the fact that it
didn't work for him or her--
you cannot tell here if
it's a boy or a girl--
could be of two causes.
Maybe she's doing
something wrong,
or maybe the toy is broken.
And found a way to
get to the other toy.
Now it turns out that what small
children are most interested
about are cause and effect.
They want to understand
cause and effect.
You know how small children
ask why all the time?
Why ne, ne, ne?
Why da, da, da?
Why that?
Sometimes it drives you nuts.
But they ask because
they want to understand.
They understand very early
on that every effect is
linked to some cause.
And they want to
understand that.
Now what that does,
is it also makes
for a very specific prediction.
And the prediction is that
when children like this
will see a situation
which violates
their expectation, then
they would be most curious.
Because that disagrees
with what they expected.
They want to
decrease to a minimum
their predictive errors.
Which is-- I'm sure you do in
your professional life, too--
is try to reduce to a minimum
your predictive errors.
Now here is an experiment
that tested this idea.
And the experiment looks
something like this.
There is an object--
this blue object,
which looks, you know,
it's not symmetrical--
and the object can
in principle be put
in equilibrium on this pole.
Now the experiment was done
with three groups of children.
Ones aged, roughly, average
five, six, and seven.
So what the researchers
did was the following.
First, they asked
the kids, you know,
to try to balance this
asymmetrical object
on the pole.
Now there were kids,
especially the--
well, there are the
smaller kids who
really didn't know what to do.
But the middle kids, they
tended, more than not,
to try to balance it at
the geometrical middle.
You know, like
lower left picture
there, where it is balanced
exactly in the middle.
The somewhat bigger kids--
actually who had some
notion of center of mass,
things like that--
tried to balance it more
closer to the heavier
edge, like in the top
right image, in this case.
Now, what the researchers did
was something very clever.
The kids took the thing, and
wanted to place it there.
The researchers looked
to see, where do they
try to place it, in the middle,
or close to the heavier edge.
But before they put it there,
they grabbed the from them.
So they knew now what was
the belief of the children.
They knew if the
children thought
that it is in the middle,
or thought that it
is at the center of mass.
Now they showed the kids a
particular configuration--
let's say like the
lower left, where
it's balanced in the middle.
That was belief
consistent to the kids who
thought it should
be in the middle,
and belief violating to the
kids who thought it should
be at the center of mass.
And what they discovered
is that whenever
it was belief violating,
the kids really
wanted to explore more.
The other kids just wanted
to play with a new toy.
And this was true also in
the other case, you know,
where it was at
the center of mass.
Again, the same type of
situation repeated itself.
Now they even
added another trick
on to this, when they showed
some kids that actually
the thing was
balanced where it was
balanced because there
was a magnet there,
holding it in place.
Once they showed that
there is a magnet there,
the kids didn't care any more
if it was belief violating,
because they say, oh, the
magnet does it, and that's it.
So kids really are interested
in cause and effect,
very, very much.
OK, how did we get to
the situation, where
our brains are able to do all
these questions why, and so on,
and this?
And other animals, believe
it or not, they cannot.
I mean, we are the only
species that asks why.
Other animals can be
curious, but they are not
interested in why.
How do we know that?
How do we know that
chimpanzees don't know--
well, these are
gorillas-- but how
do we know that
chimpanzees don't ask why?
I'll tell you how.
There's a very
interesting experiment
that did the following.
Took kids-- average age
between three and five--
and a whole bunch
of chimpanzees.
And they took an object which
looked completely symmetrical,
and it could be made to
stand, but the researchers hid
inside some weights that made
it such that you couldn't really
make it stand.
It just kept falling.
Whatever you did,
it kept falling.
The kids-- these
very small kids--
once they saw you
cannot make it stand,
more than 60% of
them took the thing,
examined it from all sides,
examined it with their hands,
you know, and so on.
None of the chimpanzees
did any of that.
The chimpanzees just kept
trying to make it stand.
The chimpanzees really
did not understand
that there is some
hidden question here
that needs to be answered--
why that thing doesn't stand.
They even identified,
actually, the region
in the brain that is
different between humans
and, let's say, macaque monkeys.
They did experiments
with macaques.
So humans are the
only ones who ask why.
Now why is that?
Well, partly it may
be related to the fact
that we have about 86
billion neurons in our heads,
and the chimpanzees or gorillas,
they have about a third
of that.
Now how did all of that happen?
In particular, what
counts is the neurons
in our cerebral cortex,
and in the striatum.
This is where, you know, all
our consciousness, if you like,
lies.
This is Lucy.
This is the skeleton of Lucy.
This is the nearly human female
that was found in Ethiopia.
It dates to 3.2
million years ago.
It's a pre-human type thing.
This is what they think
Lucy probably looked like.
She was about 3 and 1/2 feet
tall, walked mostly upright,
and ate probably mostly fruit--
but was a vegetarian in
general, mostly fruit.
But then when you start
looking at the Homo species--
you know, Homo
habilis, the handyman;
and then Homo erectus,
that walks on two feet;
and eventually Homo
sapiens, which we are--
and you look at the way
their brain increased,
it is something amazing.
I mean, the brain, from
the time of Lucy, increased
by a factor of three, or so.
And what caused that?
Well it turns out that's
a complicated question,
because the brain also
consumes a lot of energy.
The human brain
consumes about 25%
of the energy
consumption of the body,
even though in weight our brain
is only like 3%, or something.
In other species the brain
consumes only about 10%
of the energy
consumption of the body.
So why is that?
What's going on?
Well, the real
difference in that
is in the number
of neurons we have.
And like I said, especially
in our cerebral cortex.
But, OK, so there is a
difference between primates--
which is, you know, all the
apes and us-- and other species.
And that difference
is in how many
neurons you can pack
into a smaller volume.
In humans it scales linearly.
Namely, if you want
a brain to have
twice the number of neurons,
the brain will weigh twice.
So it scales linearly.
On the other hand, in, let's
say, rodents, or the power load
is completely different.
If you want a brain that
has 10 times more neurons,
the brain has to
weigh 50 times more.
So that gives primates
their first advantage
over other species.
We can cram more neurons
into a smaller volume.
But that still doesn't
explain why we ask why,
and not the chimpanzees,
and the gorillas,
and so on, which are
actually even bigger than us.
But this is where this business
of the energy comes in.
Because, you see, there
is only so much energy
that an animal can produce
from foraging for food.
Because an animal cannot search
for food for more than eight
or nine hours a day,
or it would just die.
So you look at the maximum
that it can forage,
and then you look at, OK, how
much weight you can support,
and what kind of a
brain you can support.
And when you look at
that, in simple terms,
it turns out that
for 165 pounds,
let's say, you can
support, at most, maybe
30 billion neurons--
which is about a
third of what we have.
So what gave us this advantage
over these other primates?
Well, nobody knows precisely
the answer to that,
but it's probably a
combination of a few factors.
One is, believe it
or not, cooking.
So you're here at Google.
You get very good food,
which is being cooked,
and that's very good.
Because cooking allows
you to get more energy
from the same type of thing,
because you can digest it
more easily.
You can digest types of food
that otherwise our body could
not digest, you know, like rice,
let's say, or things like that.
And so there are a
few other things.
The digestive
system, as a result
of cooking and other things,
became shorter in humans.
And the digestive system
consumes a lot of energy
by itself.
Walking upright is another
thing, because walking on four,
and knuckles consumes more
energy than walking on two.
And what I like to say
is that curiosity also
played a role in this mix, in
a way of some sort of feedback.
Because, you see, imagine
these early humans once
saw a fire hit the forest, and
then some animal got burned.
Then out of curiosity, OK,
they tried to eat that.
And they found that, aha,
this is easier to chew,
and it tastes, maybe,
better, and things like that.
Or, you know, Homo habilis
started to do some tools.
He or she discovered
that, oh, if I somehow
sharpen this branch here,
then I can get into the bones
and get the bone marrow out of
that, and that's very tasty.
And things like that.
So a combination of these
factors gave us our advantage.
Now from everything
I've told you so far,
you realize that
curiosity actually
is one of the most important
things in our lives.
Because it drives
almost everything
we do, from a simple
conversation--
you would not have a
conversation with somebody
if he or she bores you stiff.
I mean, you have to be
somewhat curious about what
they have to say.
You would not read
a book, or a blog,
or anything if you're
not curious about what
this person has to say.
You will not see a
film if you are not
somewhat curious about it.
And you will not get
involved in research
if you are not
curious about it--
unless, of course,
your boss forces
you to get engaged
in that research.
But generally, I
mean, somebody had
to be curious
about that in order
to start that research project.
Right?
So curiosity drives
all of these things.
Now given that
that's the situation,
you might have thought that
at all times, and at all ages,
people would always encourage
and support curiosity.
Well, that's not the case.
For example, in the
Middle Ages, there
were entire periods
where, you know,
church orthodoxy or
other things actually
tried to build walls around
various types of knowledge
and say, oh, we
already know everything
that is worth knowing,
and you shouldn't
be curious about other things.
That's not good for you.
This manifested itself
even in fairy tales.
Here is just a drawing of
Hansel and Gretel, you know,
who go exploring in the forest,
find this house made of candy,
and fall into the hands
of a cannibalistic witch.
That's not exactly
encouraging curiosity.
And there are more
complicated things than this.
In 1937 the Nazi regime
organized in Munich
the Degenerate Art Exhibit,
where they collected all
the works of all the masters
of modern art-- you know,
Ernst Ludwig Kirchner, Paul
Klee, all these people--
and put them together
in an exhibit
which was supposed to
convince the masses that this
is all some malicious
plot of Jews
in communist against Germany.
This is Goebbels visiting
this art exhibit.
So you see all of
these things, and we
must be very careful
about our curiosity.
And I coined a phrase,
which I'm very proud of,
which is, curiosity is
the best remedy for fear.
Because, you see, we are
very often afraid of things
that we don't know,
or don't understand,
or look strange to us.
And if you become
curious about them,
then you are not any
more fearful of them.
And I was very satisfied
when I discovered that--
you know, I thought I invented
this phrase, and I did.
But I wasn't the only one
who thought about something
like this.
In 2008 there was an art
exhibit in Copenhagen,
and they put this sign up--
replace fear of the
unknown with curiosity--
which is very much the same.
Now as part of this
book I also, I told you,
I interviewed nine exceptionally
curious people who live today.
So I'll tell you very
quickly who they are.
So Freeman Dyson-- who is
a legendary physicist--
Noam Chomsky, Story
Musgrave, Fabiola Gianotti,
Marilyn vos Savant, Jack
Horner, Martin Rees, Brian May,
and Vik Muniz.
Let me tell you very
briefly who they are.
Vik Muniz is a Brazilian artist
who recreates works of art
from everything.
From chocolate syrup he can
recreate the "Mona Lisa."
From mustard and diamonds
he recreates, you
know, maybe "The Night Watch."
He used garbage and
garbage collectors
to recreate masterful
works of art.
Brian May was the lead guitarist
of Queen, the rock band.
But he's also a PhD
in astrophysics.
He was the Chancellor of John
Moores University in Liverpool.
He's a big, big advocate
for animal rights.
He is an expert in
Victorian stereophotography.
So he has many interests.
Lord Martin Rees, a
very famous cosmologist,
but also founded the Center
for Existential Risks,
about all the risks
that humanity is facing,
and things of that nature.
Jack Horner is from Montana.
He is a big paleontologist.
He was science advisor to all
the "Jurassic Park" movies.
He's also extremely dyslectic.
He told me that he can read
today like a second grader.
And, you know, when I asked
him, how is that possible?
How can you do research
if you cannot read?
And you know what he told me?
He said, I tell my students,
if you do it first,
you don't have to
read that much.
And it's true, at some level.
Marilyn vos Savant is
actually an autodidact--
she never finished even
an undergraduate degree--
but she has the highest
recorded IQ in history, 228.
I remind you that above 140,
you're considered a genius.
So now, of course,
the scale, actually,
is completely unreliable by the
time you get to those places.
But the fact that she's very
high up there is enough.
This is Fabiola Gianotti.
She is the Director
General of CERN in Geneva.
You know, the Large
Hadron Collider?
She led one of the teams that
discovered the Higgs boson.
But her first
degree was in music.
She is an accomplished pianist.
Plays to this very day.
Story Musgrave-- a
very famous astronaut--
he serviced the Hubble
Space Telescope.
But he also has degrees in
literature, in engineering,
in computer science.
He's a medical doctor, he's a
pilot, he has seven children.
[LAUGHTER]
I mean, you know, he
just did everything.
Noam Chomsky needs
no introduction.
He's a very famous linguist, but
also interested in the brain,
in music, in many things.
He's a political
activist, and so on.
And Freeman Dyson is
a legendary physicist.
You know, formulated
different versions of QED--
of quantum electrodynamics.
But he did-- there is almost no
branch in physics, mathematics,
and so on, he didn't work on.
Even biology.
So these were the
people I interviewed.
And the thing that I found most
amazing about each one of them
is the following.
And that's maybe
the biggest lesson.
That at every stage
in their life,
it doesn't matter what their
principal occupation was,
they were open to new
problems and questions.
They saw around them, all
the time, new opportunities
and new things that
need to be solved.
You know, Freeman Dyson,
after his 90th birthday,
give an interview where he tries
to find an algorithm that will
make clinical trials safer.
You know, at his 90th birthday.
So at all ages you
can still be curious.
Now I cannot finish a talk about
curiosity without returning
to Leonardo, who said once,
"Blinding ignorance does
mislead us.
O!
wretched mortals,
open your eyes!"
And the one person
that is my icon--
I'm an astrophysicist-- and who
opened his eyes all the time.
Einstein here opening his eyes
once, and twice, and thrice.
Thank you very much.
[APPLAUSE]
MARK: Hey, we have a little
bit of time for questions.
And here's a question.
AUDIENCE: What would you say is
the relation between creativity
and curiosity?
MARIO LIVIO: Yes.
The relation between
creativity and curiosity.
OK, so there is this very
well-known psychologist
from the University of Chicago.
He's now retired,
but very well-known.
His name is Mihaly
Csikszentmihalyi.
And he actually did a
big study on creativity.
In particular, he interviewed
about 100 creative people.
And he discovered that
curiosity was absolutely
essential to each one of them.
So creativity and
curiosity are not the same,
but curiosity appears to
be a necessary ingredient
for creativity.
Any other questions?
MARK: Other questions?
AUDIENCE: So sometimes I
think about the downside
of curiosity.
MARIO LIVIO: The what?
AUDIENCE: The downside
of curiosity--
MARIO LIVIO: Yes.
AUDIENCE: --which is
the fear of missing out.
I think that I feel like
I don't have enough time
to try everything, and I
often feel sad about that.
When you interview
people-- or maybe yourself,
when you think about
that, what do you think?
How people deal with that?
MARIO LIVIO: Yes.
So, indeed, look, you cannot
be curious about everything.
There just isn't
enough time for that,
even if you wanted
to be curious.
So you do have to be a little
bit selective in the things
that you get curious about, yes.
But the thing is the following.
The problem is very often the
opposite of what you describe.
Namely, people who get so
immersed in what they do,
that, you know,
it's not even clear
that they are driven
any more by curiosity.
Maybe they are just driven
by the wanting to succeed.
Which is not exactly
the same, yes?
So they want to succeed, or
they want to make more money.
So they are not really
driven by curiosity.
They are driven by wanting
to make more money.
I'm not saying there is
something against that.
But this is more
often the problem
than the problem you describe.
You describe somebody
who is curious, wants
to be curious about
many things, but maybe
doesn't quite have the time to
get curious about everything.
So, you know,
prioritize your things.
Namely, choose a few things that
you are really curious about,
and get interested about them.
And, you know, in
different stages in life,
you actually may do--
you see, I didn't
start writing books.
I worked in astrophysics
most of my life.
And only in 2000 I started
writing popular science books.
This is my sixth book.
So until that, I wasn't that
interested in writing books.
I wanted to write papers.
I wrote more than 400 papers.
But then at one point in my
life, I said, you know what,
suppose I will write
10 more papers,
20 more papers, 50 more papers.
Is that really going to
make a huge difference?
And, you know, very often
you decide that probably not,
because being a
theoretical physicist,
we tend to do our best work
when we're relatively young.
So at that point
I said, well, let
me try to reach a
broader audience,
you know, and so on,
and started to be
interested in science writing.
So you may still find
the time in your life
when you would be curious
about something else.
I, all the time, for example,
I am very interested in art--
was always interested in art.
So I, you know, do science,
and I always liked art.
I have no talents in art, but
I'm very interested in art,
so I have many art books
and things like that.
Yes, please.
AUDIENCE: There
have been arguments
about how violence-- for
instance, Steven Pinker
wrote a book saying that
violence has decreased over,
you know, since the beginning
of dawn of humanity till now.
He did, like, 500
pages of research.
Similarly, we know
that life expectancy
has increased over time.
Can we say something like
that about curiosity?
Do you think it has changed,
or increased, or decreased?
MARIO LIVIO: So, yes.
So this is a very important
question, I think.
So there are many people
who think, for example,
that curiosity
decreases with age.
Because they say, look,
children are so curious
and, so on, and then
they are less curious.
Well, research shows that
that's not quite the case.
What happens is that diversive
curiosity, and perhaps
perceptual, does decrease
somewhat with age.
Namely, search for novelty,
and willing to take
risks for novelty does
decrease somewhat with age.
But epistemic
curiosity, for example,
this love of
knowledge, and so on,
actually stays fairly
constant across the time.
Now has it changed in terms of,
you know, evolution of humans?
Well, clearly, you
know, I have to think,
even though nobody
knows with certainty,
that this huge
advantage that we got,
in terms of the
number of neurons
in our cerebral
cortex and striatum
had to do something
with the fact
that we are so much more curious
than these other species.
So presumably during evolution a
change of that kind did happen.
Now at the same time I noted
these periods in our history
where, sometimes
curiosity is suppressed,
or you know, and
so on, so we have
to be very careful about those.
Yes.
AUDIENCE: Does being curious
have a compounding effect?
That is to say, if you are--
MARIO LIVIO: Curious, do
you become more curious?
AUDIENCE: Right.
MARIO LIVIO: Well, you know, I'm
not sure what you do at Google,
but scientists usually
are in a state where
almost answering almost
every question just raises
more questions.
And sometimes more
profound questions.
For example, in fundamental
physics, that's the case.
We keep pushing the questions
farther and farther.
Today we answer questions that
100 years ago, we didn't even
know how to ask.
So there is no
question that there
is an element like this,
that you could actually
become even more curious.
But certainly the
opposite is true.
I think if you
allow yourself not
to be curious for a long period
of time, you're probably,
you know, declining to a
state of lower curiosity.
Now mind you, every
person is curious.
Other than people who
suffer from deep depression
or have certain brain
injuries, everybody's curious.
Not everybody is
curious the same,
in the same way that not
everybody is intelligent
the same, or has some
talents the same.
And also not everybody is
curious about the same things.
But they may be curious
about other things.
MARK: And we have
one more question.
MARIO LIVIO: Please.
AUDIENCE: Hi, this
was a wonderful talk,
and my last question, I guess,
is about what you believe is--
how do I ask this?
So one way to think
about curiosity, I guess,
is that curiosity can be
like a resulting phenomenon
from a situation in which you
do have sufficient knowledge,
but not enough knowledge to
really understand something.
MARIO LIVIO: Right, that's
the information gap, yes.
AUDIENCE: And then on
the other side of things,
you could also think of,
like, human capabilities
to feel curious, and/or human
capability to take effect
and/or act upon that
kind of curiosity.
I'm wondering what
your views are
on whether you can improve a
human's capability to feel more
curious, or things like that.
MARIO LIVIO: Yeah.
So I think this should
start from small children.
And the way I think that
works is, you see, sometimes--
this is a new book,
so I've only had,
so far, a few talks on this.
But people ask me, how do I
make my child more curious?
You know, people ask
me questions like this.
Or somebody asked me, how do I
make my coworkers more curious?
And the way to achieve that--
again, I'm not a
specialist in education,
but that's my perception from
everything I've now read,
you know, and then learned--
is that you have to start with
things that they are already
curious about.
And the example
I like to give is
that most small children
are curious about dinosaurs,
for example.
Most American small children
are curious about dinosaurs.
So if you want to
teach them science,
don't start with trying to
explain to them the free fall
acceleration, which they really
don't care about, at all.
Start with dinosaurs!
Because they are already
interested in that.
And then from
dinosaurs, you know,
you can perhaps lead them.
If you think about this
thoughtfully enough,
you can find a way.
You could start
with the dinosaurs,
and then the
dinosaurs, we think,
became extinct because of an
asteroid that hit the Earth.
And once an asteroid hit
the Earth you start to--
I'm just saying maybe
you wanted to tell them
about free fall acceleration.
So you say, OK, an
asteroid hit the Earth.
Oh, we can actually
try to calculate
how much energy is an asteroid
that hits the Earth, and so on.
So start with what
interests them already,
instead of starting
with what you think
they should be interested in.
Because they may not
be interested in that.
MARK: Thank you so much
for coming to Google.
MARIO LIVIO: My pleasure.
MARK: And we know
that you're now
working on the next
book-- which you say
might take four or five years.
And I'm wondering-- I'll remind
you all, this one is "Why?"
And we can pick up
copies here today.
And I'm wondering if the next
one might be Z for z answer.
We'll have to stay
tuned to find out.
Thank you again, Mario Livio.
MARIO LIVIO: My pleasure.
[APPLAUSE]
