I was hopelessly stuck.

Every research direction that I tried

led to a dead end.

It seemed like my basic assumptions

just stopped working.

I felt like a pilot flying through the mist,

and I lost all sense of direction.

I stopped shaving.

I couldn't get out of bed in the morning.

I felt unworthy

of stepping across the gates of the university,

because I wasn't like Einstein or Newton

or any other scientist whose results

I had learned about, because in science,

we just learn about the results, not the process.

And so obviously, I couldn't be a scientist.

But I had enough support

and I made it through

and discovered something new about nature.

This is an amazing feeling of calmness,

being the only person in the world

who knows a new law of nature.

And I started the second project in my Ph.D,

and it happened again.

I got stuck and I made it through.

And I started thinking,

maybe there's a pattern here.

I asked the other graduate students, and they said,

"Yeah, that's exactly what happened to us,

except nobody told us about it."

We'd all studied science as if it's a series

of logical steps between question and answer,

but doing research is nothing like that.

At the same time, I was also studying

to be an improvisation theater actor.

So physics by day,

and by night, laughing, jumping, singing,

playing my guitar.

Improvisation theater,

just like science, goes into the unknown,

because you have to make a scene onstage

without a director, without a script,

without having any idea what you'll portray

or what the other characters will do.

But unlike science,

in improvisation theater, they tell you from day one

what's going to happen to you when you get onstage.

You're going to fail miserably.

You're going to get stuck.

And we would practice staying creative

inside that stuck place.

For example, we had an exercise

where we all stood in a circle,

and each person had to do the world's worst tap dance,

and everybody else applauded

and cheered you on,

supporting you onstage.

When I became a professor

and had to guide my own students

through their research projects,

I realized again,

I don't know what to do.

I'd studied thousands of hours of physics,

biology, chemistry,

but not one hour, not one concept

on how to mentor, how to guide someone

to go together into the unknown,

about motivation.

So I turned to improvisation theater,

and I told my students from day one

what's going to happen when you start research,

and this has to do with our mental schema

of what research will be like.

Because you see, whenever people do anything,

for example if I want to touch this blackboard,

my brain first builds up a schema,

a prediction of exactly what my muscles will do

before I even start moving my hand,

and if I get blocked,

if my schema doesn't match reality,

that causes extra stress called cognitive dissonance.

That's why your schemas had better match reality.

But if you believe the way science is taught,

and if you believe textbooks, you're liable

to have the following schema of research.

If A is the question,

and B is the answer,

then research is a direct path.

The problem is that if an experiment doesn't work,

or a student gets depressed,

it's perceived as something utterly wrong

and causes tremendous stress.

And that's why I teach my students

a more realistic schema.

Here's an example

where things don't match your schema.

(Laughter)

(Applause)

So I teach my students a different schema.

If A is the question,

B is the answer,

stay creative in the cloud,

and you start going,

and experiments don't work, experiments don't work,

experiments don't work, experiments don't work,

until you reach a place linked with negative emotions

where it seems like your basic assumptions

have stopped making sense,

like somebody yanked the carpet beneath your feet.

And I call this place the cloud.

Now you can be lost in the cloud

for a day, a week, a month, a year,

a whole career,

but sometimes, if you're lucky enough

and you have enough support,

you can see in the materials at hand,

or perhaps meditating on the shape of the cloud,

a new answer,

C, and you decide to go for it.

And experiments don't work, experiments don't work,

but you get there,

and then you tell everyone about it

by publishing a paper that reads A arrow C,

which is a great way to communicate,

but as long as you don't forget the path

that brought you there.

Now this cloud is an inherent part

of research, an inherent part of our craft,

because the cloud stands guard at the boundary.

It stands guard at the boundary

between the known

and the unknown,

because in order to discover something truly new,

at least one of your basic assumptions has to change,

and that means that in science,

we do something quite heroic.

Every day, we try to bring ourselves

to the boundary between the known and the unknown

and face the cloud.

Now notice that I put B

in the land of the known,

because we knew about it in the beginning,

but C is always more interesting

and more important than B.

So B is essential in order to get going,

but C is much more profound,

and that's the amazing thing about resesarch.

Now just knowing that word, the cloud,

has been transformational in my research group,

because students come to me and say,

"Uri, I'm in the cloud,"

and I say, "Great, you must be feeling miserable."

(Laughter)

But I'm kind of happy,

because we might be close to the boundary

between the known and the unknown,

and we stand a chance of discovering

something truly new,

since the way our mind works,

it's just knowing that the cloud

is normal, it's essential,

and in fact beautiful,

we can join the Cloud Appreciation Society,

and it detoxifies the feeling that something

is deeply wrong with me.

And as a mentor, I know what to do,

which is to step up my support for the student,

because research in psychology shows

that if you're feeling fear and despair,

your mind narrows down

to very safe and conservative ways of thinking.

If you'd like to explore the risky paths

needed to get out of the cloud,

you need other emotions --

solidarity, support, hope —

that come with your connection from somebody else,

so like in improvisation theater,

in science, it's best to walk into the unknown

together.

So knowing about the cloud,

you also learn from improvisation theater

a very effective way to have conversations

inside the cloud.

It's based on the central principle

of improvisation theater,

so here improvisation theater

came to my help again.

It's called saying "Yes, and"

to the offers made by other actors.

That means accepting the offers

and building on them, saying, "Yes, and."

For example, if one actor says,

"Here is a pool of water,"

and the other actor says,

"No, that's just a stage,"

the improvisation is over.

It's dead, and everybody feels frustrated.

That's called blocking.

If you're not mindful of communications,

scientific conversations can have a lot of blocking.

Saying "Yes, and" sounds like this.

"Here is a pool of water." "Yeah, let's jump in."

"Look, there's a whale! Let's grab it by its tail.

It's pulling us to the moon!"

So saying "Yes, and" bypasses our inner critic.

We all have an inner critic

that kind of guards what we say,

so people don't think that we're obscene

or crazy or unoriginal,

and science is full of the fear

of appearing unoriginal.

Saying "Yes, and" bypasses the critic

and unlocks hidden voices of creativity

you didn't even know that you had,

and they often carry the answer

about the cloud.

So you see, knowing about the cloud

and about saying "Yes, and"

made my lab very creative.

Students started playing off of each others' ideas,

and we made surprising discoveries

in the interface between physics and biology.

For example, we were stuck for a year

trying to understand the intricate

biochemical networks inside our cells,

and we said, "We are deeply in the cloud,"

and we had a playful conversation

where my student Shai Shen Orr said,

"Let's just draw this on a piece of paper, this network,"

and instead of saying,

"But we've done that so many times

and it doesn't work,"

I said, "Yes, and

let's use a very big piece of paper,"

and then Ron Milo said,

"Let's use a gigantic architect's

blueprint kind of paper, and I know where to print it,"

and we printed out the network and looked at it,

and that's where we made our most important discovery,

that this complicated network is just made

of a handful of simple, repeating interaction patterns

like motifs in a stained glass window.

We call them network motifs,

and they're the elementary circuits

that help us understand

the logic of the way cells make decisions

in all organisms, including our body.

Soon enough, after this,

I started being invited to give talks

to thousands of scientists across the world,

but the knowledge about the cloud

and saying "Yes, and"

just stayed within my own lab,

because you see, in science, we don't talk about the process,

anything subjective or emotional.

We talk about the results.

So there was no way to talk about it in conferences.

That was unthinkable.

And I saw scientists in other groups get stuck

without even having a word to describe

what they're seeing,

and their ways of thinking

narrowed down to very safe paths,

their