Hello, everybody.

Thank you for being here.

In childhood, I wrote dozens of poems,

and in my poetry,

I tried to express my feelings
about loneliness,

my questions about death,

my unrequited love
for 14-year-old girls.

(Laughter)

Reading, listening, even thinking,

I was mesmerized by the sounds
and the movements of words.

Words could be sudden, like "jolt,"

or words could be slow, like "meandering,"

words could be silvery,
prickly to the touch,

and by magic, words
could create scenes and emotions.

Between poems,
I did scientific experiments,

and these I conducted
in a little laboratory,

a homemade laboratory
that I built off my second-floor bedroom,

really, a large closet.

And there I hoarded resistors, capacitors,

wire of various lengths,

test tubes, beautiful pieces of glassware.

I loved my equipment;
I loved to build things.

By the age of 12,

I had built a remote-control device

that turned on the lights in any room
of the house from any other room.

When my scientific projects went awry,

I could find certain fulfillment
in mathematics.

In geometry,

I loved the inexorable relationships
between lines and angles.

And in algebra, I loved the abstraction -

I loved letting X's and Y's

stand for the number
of nickels and pennies in a jar

and then solving
a connected set of equations

one logical step after the other.

I loved that shining purity
of mathematics,

that precision.

I loved the certainty of mathematics.

In mathematics,

you were guaranteed an answer

as clean and as crisp
as a new 20-dollar bill,

and when you found that answer,

you knew that you were right,
unquestionably right -

the area of a circle
is pi r-squared, period.

Mathematics contrasted strongly

with the ambiguities
and the contradictions of people.

The world of people confused me;

the world of people
had no logic or certainty:

My Aunt Jean continued to drive recklessly
in her little MG sports car

even though everyone in the family

told her that she would kill herself
in that car one day.

We had a wonderful woman named Blanche,
who worked for our family for years.

Blanche had to leave her husband
after he abused her,

and then, for many years later,
spoke about him with affection.

So how does one reconcile
these different worlds,

these seeming contradictions?

Well, now having lived
in two communities,

the community of scientists
and the community of artists,

for many years -

I've worked both as a physicist
and as a novelist -

I have tentative answers
to some of these questions.

So I wanted to tell you this morning
a little bit about what I've learned

about the different ways that scientists
and artists approach the world -

their different versions of truth
and also some of the many similarities.

A big distinction that I have found
between physicists and novelists

or, I should say, more generally,
between scientists and artists

is in what I will call
"the naming of things."

Roughly speaking,

the scientist tries to name things

and the artist tries
to avoid naming things.

To name a thing,

you've gathered it, you've distilled it,

you've purified it,

you've put a box around the thing

and said what's in the box is the thing

and what's not in the box
is not the thing.

Consider, for example,
the word "electron,"

which is a type of subatomic particle.

As far as we know,

all of the zillions of electrons
in the universe are identical;

there's only a single kind of electron.

And to a modern physicist,

the word electron
means a particular equation -

it's called the Dirac equation.

And that equation summarizes everything
that we know about electrons:

the precise energy of electrons in atoms
as they orbit the nucleus,

the deflections of electrons
in magnetic fields -

all of that can be predicted
to many decimal places

with great accuracy by the Dirac equation.

Every object in the physical universe

the scientist wants to be able to name
with this kind of precision.

For scientists,
it's a feeling of comfort,

a feeling of power,

and a sense of control

to be able to name things in this way.

The concepts that the artist
deals with cannot be named.

The novelist might use a word
like "love" or like "fear,"

but those words don't really convey
that much to the reader.

For one thing, there are
a thousand different kinds of love:

there's the love
that you feel for a mother

who writes you every day
your first summer away from home

at summer camp;

there is the love that you feel for a man
or a woman that you've just made love to;

there's the love
that you feel for a friend

who calls you right
after you've split up from your spouse;

and on and on.

But it's not just
the many different kinds of love

that prevent the novelist
from truly naming the thing,

it's that the particular situation

that creates the particular ache of love.

That particular situation
must be shown to the reader -

not named but shown
through the actions of characters.

And if love is shown rather than named,

then each reader will experience it
in her own individual way,

each reader will draw on her own
adventures and misadventures with love.

Every electron is identical,
but every love is different.

The novelist doesn't want to try
to eliminate these differences,

doesn't want to try to distill
the meaning of love

so that there is only a single meaning,
as in the Dirac equation,

because such a distillation is impossible

and even an attempt at such a distillation

would destroy that magical, delicate,
participatory creative act

that happens when a good reader
reads a good book.

In a sense a novel is not completed
until it is read by a reader

and every reader completes the novel
in a different way.

Well, there's another phenomena
that's closely related to naming,

and that is framing problems
in terms of questions with answers.

We scientists work by breaking the world
down into smaller and smaller pieces

until we have what we call
well-posed problems

that have clear and definite answers.

It might take five years, it might take
a hundred years to find the answer,

but at any given moment of time,

each scientist is working on something

that he or she feels
has a definite answer;

for example, one such question might be:

Where in a living organism
are the instructions stored

to create a new organism?

This is a well-posed problem
with a definite answer;

it was answered in the 1800s and 1900s.

But artists often don't care
what the answer is

because often answers - definite answers -
don't exist in the arts;

the arts are complicated

by the intrinsic ambiguities
and self-contradictions of people.

This is one of the reasons

why the characters in a good novel
can be debated endlessly,

why God held the apple in front of Eve
and then forbade her to eat it.

In the arts,

there are many, many interesting questions
that don't have answers,

such as "Does God exist?"
or "What is the nature of love?"

or "Would we be happier
if we live to be a thousand years old?" -

and I'm grouping the arts
and the humanities together here.

These are very interesting questions;

they provoke us,
they stimulate our imagination,

but they don't have clear
and definite answers

or maybe no answers at all.

As the poet Rainer Maria Rilke wrote,

"We should learn to love
the questions themselves

like locked rooms and like books
written in a very foreign tongue."

And I have finally come to believe
that we need both kinds of questions:

we need questions with answers
and we need questions without answers -

that both kinds of questions
are part of being human.

Well, I've been speaking
about some of the differences

between the sciences and the arts -

let me say a little bit
about some of the similarities.

The folklore

is that artists make up everything
and scientists don't make up anything.

Well, both views are false.

The imagination has always been important
in a great scientist.

And Albert Einstein
had a phrase that he used -

he called it "the free invention
of the mind" in the sciences,

and by that, the great scientist meant

that we cannot discover
all of the truths of nature

simply by observation and experiment,

that sometimes we have
to start with mental constructions

and then only later test those
against experiment.

And one of the greatest examples
of Einstein's "free invention of the mind"

was his work on time,
called "the theory of special relativity."

And in that work, Einstein
begins with the stunning postulate

that a light ray passes us
at the same speed

whether we're running
towards the light ray

or away from it -

it makes no sense based
on our day-to-day experience,

it violates common sense,

and yet Einstein realized
that our common sense could be in error

when it comes to the very
high speeds of a light ray,

and he made this leap of the imagination.

But scientists can't make up everything
even when they're developing new theories;

I mean, you can't put forth
a new law of gravity

that says apples fall up instead of down -

there's still a large body
of known experimental evidence

that we have to accord with.

And I would argue that in the same way,

there's a body of experimental evidence
that the artist must accord with -

it is the large catalog of known behavior
in psychology of human beings

called human nature,

and those are the facts
that the artist must accord with.

And let me give you an example
of what I'm talking about there.

Suppose a novelist
has created a character:

a man about 40 years old,
married with two children,

who's just attended a Christmas party.

Just for the sake of referring to him,
let's call this fellow Gabriel.

Well, we learn at
the beginning of the story

that Gabriel is not too sure of himself -

he worried when he first got
into the Christmas party,

he worried that he had insulted
the housekeeper's daughter,

and a little bit later,

he's worrying that his after-dinner speech
is going to be condescending.

Well, anyway, the party ends.

Gabriel and his wife Greta have left
their two children with a babysitter;

they've decided to spend the night
at a nearby hotel.

Greta's been very quiet
during the evening.

So they walk out of the house,

and they begin walking on a path

towards their hotel
in this little village.

It's well after midnight now;
it's beginning to snow.

Gabriel looks over at his wife
and admires her

and hopes that she still feels
in love with him

even though she's had the drudgery
of house work and children.

So they reach their hotel,

and they walk up
this narrow curving stairway

that's lit only by candlelight,

and they enter their room,

and by this time, Gabriel is feeling
a lot of desire for his wife, Greta.

And instead, she turns away from him
and she begins weeping.

And he asks her, "Why are you crying?"

And she says that there was a sad song
sung at the Christmas party

that reminded her of a boy

that she used to know
long ago in her youth,

a boy with large brown eyes.

They used to go walking together.

Gabriel feels a dread in his stomach,

and he asks his wife,
"Were you in love with this boy?"

And she says, "Yes,
we were great together at the time."

And then Greta says, "He died at age 17."

"What did he die of
so young?" asks Gabriel.

"I think he died for me," says Greta,

and she begins sobbing all over again
and throws herself to the bed.

Well, this scene that I've just described,
as some of you know,

is the last scene of James Joyce's
famous story The Dead,

and the question is:
How will Joyce end the scene?

What will be Gabriel's reaction
to his wife's confession?

Suppose that he shows no reaction -

would we as readers with our
life experience believe that reaction?

No, it would ring false.

Or suppose Gabriel feels superior
to this boy of the distant past,

this long dead boy,
and dismisses his wife's pain -

would we believe that reaction?

No, we wouldn't believe that either,

because we know that Gabriel
is too insecure a character for that.

The ending that Joyce
actually writes is this:

Gabriel realizes that his wife
has always loved this long dead boy

more than she's ever
loved him, her husband,

and he also realizes
that he's never loved any woman

with the passion that she has just
demonstrated for this boy.

And all he can do after these realizations

is sag against the windowpane,

listening to the breathing
of his wife as she sleeps,

watching her as if he and she
had never been man and wife.

We believe this ending;
we know that it's true even in fiction

because it accords
with our life experiences,

with our understanding of human nature,
and it causes us anguish.

Both the scientist and the artist
are seeking truth.

In seeking truth,

both the scientist
and the artist must invent.

Both kinds of invention are important.

Both kinds of invention must be tested
against experiment.

The tests of the scientist's invention
are more definitive;

no matter how beautiful
a scientific theory is,

it has a terrible vulnerability -
it can be proven false.

A writer's characters or story
cannot be proven definitively wrong,

but they can ring false
and thus lose their power with the reader,

and in this way, the novelist
is constantly testing his fiction

against the accumulated
life experiences of his readers.

The scientists and the artists
that I have known

have at least one more thing in common:

they do what they do because they love it

and because they cannot imagine
doing anything else -

this is a compulsion.

This compulsion is
both a blessing and a burden.

It's a blessing

because the creative life
is a beautiful life

and it's not given to all of us,

and it's a burden
because when the call comes,

it can be unrelenting
and it can drown out the rest of life.

This mixed blessing and burden

must be the sweet hell
that Walt Whitman referred to

when he realized at a young age
that he was destined to be a poet -

"Never more shall I escape,"
wrote Whitman.

This mixed blessing and burden

must be why a visitor
to the young Einstein's apartment in Bern

found the physicists rocking
the cradle of his son with one hand

and doing mathematical
calculations with the other.

Thank you.

(Applause)