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Practice English Speaking&Listening with: TEDxHouston - Dr. David Eagleman

Difficulty: 0

Translator: Tanya Cushman Reviewer: Rhonda Jacobs

By a show of hands,

how many people know what the Deep Field observation is,

by the Hubble telescope.

How many have heard of that experiment?

Okay, a few.

Okay, in 2003, NASA decided that it was going to take the Hubble Telescope,

and it was going to point it at a little dark patch of sky.

So, it had already done a low-resolution map of the cosmos.

What they wanted to see is,

what if we took this finely honed lens

and we find a little patch of sky -

about the size of a pencil tip at arm's length -

where there's nothing there,

and we point it there for a really long time,

would we be able to see a star there where it looks like there's nothing?

So what they did, starting in 2003,

is every time the Hubble came around the Earth,

they pointed the lens there for 20 minutes

to collect any lonely photons trickling in from the distant reaches of the universe.

And they did this 400 times.

And in the end, they took all of this data and they compiled it,

and they put together what was there in that little patch of space,

and they didn't find a star.

What they found were 10,000 galaxies.

A galaxy contains 100 billion stars.

So that's 1,000 trillion stars that are all just like our sun, right?

And they have innumerable solar systems and planets going around

and life forms that we can't even imagine.

That's what's teeming behind this little patch of black space.

Now, if you mapped out the whole cosmos at that resolution,

it would take a million years.

So, I think this a really good consciousness raiser

to start thinking about the size, the enormity of the mysteries

that surround us.

So I've spent my entire life in science,

and I figured if we want to understand the mysterious existence that we have,

there's no better way than to study the blueprint.

So that's what I've been doing.

And science has been tremendously successful.

We've been able to get men to stand on the moon,

and we've cured smallpox and polio,

and we've invented the internet,

and we've tripled life spans.

But what you really learn from life in science

is when you get to the end of the pier of everything we know in science,

when you get to the end and you stand there,

you see that beyond, it's all uncharted waters.

It's all the stuff that we don't know;

it's the vast mysteries around us,

like dark matter and dark energy,

or why mass and energy are equivalent,

or how you build consciousness from pieces and parts,

or what the fabric of reality is,

or what life and death are about.

These are all the things that are beyond the end of the pier in science.

And what you really learn from a life in science

is the vastness of our ignorance.

Now, we will, as we move forward,

continue to build slats out and get a little bit more each year,

but in fact, it's a giant ocean that's in front of us.

And so there's no guarantee how far we'll get,

and certainly in our brief twinkling of a 21st century lifetime,

we're not going to get that far.

So we're confronted with these very deep mysteries.

Now, given that situation,

I've been very interested by these recent books by the neo-atheists.

So, these are very important and insightful books,

but I think they've left the public with a misconception,

that scientists don't have the capacity to gamble beyond the available data,

that scientists are acting as though we've got it all figured out:

E = mc², F = ma - we sort of get it.

We get how to describe the cosmos in equations,

or if we don't know how yet,

we're pretty sure that our toolbox will capture it.

But I actually think that's not a very good description of science.

Science, actually, is extremely open-minded:

it doesn't throw out the baby with the bathwater,

where the baby is all the awe and the mystery

that drew us into science in the first place.

So science, instead, is very comfortable holding multiple ideas in mind,

saying, "Well, it might be this, it might be this."

The scientific temperament is one of creativity,

making up lots of narratives,

and then trying to find evidence to weigh in favor of one over others,

but sometimes you just can't find evidence.

There are many questions that are beyond the toolbox of science,

and in those cases,

we're perfectly comfortable holding on to all of those different narratives.

There's not a strict need to commit.

So that's what really happens in science,

and so I've been a little concerned

about this voice from the books by the neo-atheists,

whether this is how science is going to be represented.

I think that we know too little to commit to a position of strict atheism

where we act as though we've got it all figured out.

On the other end of the spectrum,

I think that we know way too much

to commit to a particular religious position.

There are 2,000 religions on the planet,

and as has been pointed out by the neo-atheists,

everybody already knows what it's like to be an atheist

because all you need to do is look at someone else's religion,

and you say, "Well, that's patently ridiculous you would believe in that."

And of course, they're looking back at you and thinking exactly the same thing.

So there are problems with committing to any particular religion.

The holy books of these different religions

were written millennia ago

by people who didn't know about the size of the cosmos

and the big bang and bacterial infection and DNA and hallucinations

and the fabric of reality -

they didn't know any of this stuff.

They didn't even know much about neighboring landscapes or cultures.

Now, what's funny is, every time I sit next to somebody on an airplane,

I always ask them,

"Hey, have you heard of the Hubble Deep Field observation?"

Nobody has.

But everybody's willing to defend their particular religious story.

You don't have to be an anthropologist

to realize that brains absorb whatever culture has poured into them.

So if you're born in Saudi Arabia, you're going to love Islam,

and if you're born in Rome, you're going to love Catholicism,

and Tel Aviv, Judaism; in India, Hinduism;

in Springfield, Ohio, you're going to love Protestantism.

And it's no coincidence

that you don't find a big blossoming of Islam

in the middle of Springfield, Ohio,

and you don't find a blossoming of Protestantism in Saudi Arabia.

If there were one truth,

you would expect it might spread everywhere evenly,

but in fact, we are products of our culture.

That should be clear.

The strange part

is that people are willing to fight and die over this product,

over the product of what gets poured into them

and the stories they're told.

Now, Ralph Waldo Emerson pointed out

that the religious stories of one generation

become the literary entertainment of the next, right?

So, think about Isis and Osiris or the Greek or Roman panoplies.

Nobody's fighting and dying over that anymore - not too much.


But I'm going to give you an example of this.

I don't know if anyone's heard of the creation story

from the Bakuba Kingdom in the Congo.

But their creation story goes like this:

There was originally a white giant named Mbombo,

and Mbombo had a sharp pain in his belly

and vomited up the stars and the moon and the earth.

I'm not making this up.

And then he had - he was not over his illness -

he had another pain in his belly and vomited again,

and this time produced the people and the animals and the trees.

And included in this second ejection was,

and I quote, "The leopard, the eagle, the anvil,

woman, the monkey Fumu,

firmament, medicine, man and lightning."

So, if you find the creation story of the Bakuba Kingdom

an unlikely explanation for how we actually got here,

just consider that if you were of the Bakuba Kingdom,

you would look at the Western story

of the naked couple and the talking snake and the prohibited produce,



and you would find that equally bizarre, right?

And if you were Bakuba and you were living in Kansas,

you would be fighting to put this in your children's text books, right?

(Laughter) (Applause)

So, I'm not suggesting

that the story of Adam and Eve is suspect because there are competing stories;

I'm suggesting it is suspect

because the available scientific evidence weighs so strongly against it.

So, the Earth is about 4.5 billion years old,

by the best of our estimates now.

The Biblical account says it's 6,000 years old.

Well, that's a problem

because it has to account for why the Japanese were making pottery

and the Magdalenians were painting cave paintings

and the Persians were domesticating goats

4,000 years before the planet existed.

So there are problems here,

and I think that we could sort of safely say

that we know maybe too little to commit to strict atheism,

but we know way too much to commit to any particular religious story.

So that puts me somewhere in the middle.

And what has surprised me

is the amount of certainty that you find when you walk into a bookstore.

So I walk in, and I find the books by the neo-atheists

and the books by the fundamentally religious,

and those are your only choices.

What happens is these are very smart people on both sides

that spend all of their energies polarizing each other

and arguing against each other's details.

And I feel like there should be another voice in there somewhere,

because in fact, if you imagine the space of possibilities -

it's enormous, right?

I mean, you've got all sorts of possibilities

for what might be going on.

So imagine this space, and take the Judeo-Christian-Islamic tradition.

That's one point in this possibility space.

And take the Eastern religions -

another point in the possibility space.

And take the idea that we're just atoms,

and when we die, we shut off and we scatter -

another point in the possibility space.

And if you start populating this,

you see that there are giant landscapes in between

of possible stories that might be going on,

and I feel like there's not enough discussion about this;

instead, there's this false dichotomy about God versus no God,

which I think is much too limited, really, for a modern discussion.

So for myself, I'm finding myself in this middle position.

Now, some people call that agnosticism,

which is a term that I think is sort of a weak term

because the way that it's typically used,

people mean, "Well, I'm not certain

if the guy with the beard on the cloud exists or doesn't exist."

That's typically what they mean:

whatever was poured into my head, you know, I have my doubts about it.

So I don't call myself an agnostic;

I call myself a Possibilian.

And the idea -


The idea with Possibilianism is an active exploration that's poured into my head -

you know, I have my doubts about it.

So I don't call myself an agnostic; I call myself a Possibilian,

And the idea -


the idea with Possibilianism

is an active exploration of this giant space,

trying to make up new narratives and figure out new stories

rather than getting caught in this false dichotomy.

So Possibilianism is now one year old.


And I first announced it in a live interview on NPR a year ago;

I defined it and talked about it,

and I left the studio and got in my truck,

and I drove back to my laboratory at Baylor College of Medicine,

and I settle in for a day's work,

and I open my inbox,

and I had hundreds of emails from people

saying, "Hey, I think I'm a Possibilian too."

(Laughter) (Applause)

So I googled the word, and it turned out that it didn't exist;

there were zero hits.

So I did what anybody would do:

I bought,


and then I waited and watched to see what happened.

Well, what happened was amazing.

What happened was Facebook groups started;

it went all over the blogosphere;

there were articles published by The New York Times and MSNBC.

The Uganda Sunday Times just published a huge article on Possibilianism.

It's gone all over the world.

If you now google it, there are 10,000 hits,

and it's really caught on in some way.

It's really caught fire.

Now, one thing I noticed:

on the radio, I said "Possibilian,"

but people misheard or misremembered,

so other groups started popping up too.

They call themselves "possibilitarians" or "probabilians,"

and they spelled it any way you can imagine.

And I thought, "That's perfect.

That's right in the Possibilian spirit -

spell it anyway you want to."


So the thing I started wondering about is,

Why, why has this caught on as a worldwide movement?

Because keep in mind, it's a joke movement, right?

We specifically don't subscribe to anything, so why is this catching on?

And I think it's because maybe people are getting a little bit tired

of the debates between Dawkins and the Discovery Institute,

maybe people are getting a little bit tired of the certainty

that is proposed about topics that one can't possibly be certain on.

So, Voltaire said, "Doubt is an uncomfortable position,

but certainty is an absurd position."

So I think that maybe it's the time

when there's just the right groundswell for this sort of idea.

Now, I want to clarify a couple of points about Possibilianism.

Sometimes when I talk about this, people will say,

"Hey, that's terrific that Possibilianism is about anything goes.

I'm so glad you're a Possibilian because then you get what I'm talking about" -

with ESP or crystals or whatever.

It's not anything goes.


It's anything goes at first.

And then what we do is we import the tools of science, right?

So it would be terrific if ESP existed; we'd all love that.

But to the extent that we're currently able to do it,

we've tested these sorts of things

and can't find any evidence to weigh in favor of it.

So Possibilianism, you can actually take the tools of science

and rigorously try to rule out parts of the possibility space

as well as open up new parts of the possibility space.

And really, the interesting part of the possibilium

comes where science leaves off,

where we're no longer able to test things,

and instead, we're at the point that's beyond science's toolbox.

That's a really interesting part of the possibility space.

And I think the reason that we know that we need to be creative

and come up with new narratives

and have tolerance for multiple ideas

is because there is so much that we're missing,

and we're aware of the amount that we're missing.

So in every generation,

scientists have always felt that they sort of have all the pieces of the puzzle:

okay, we can take Newtonian physics, Einsteinian physics and quantum mechanics,

put it all together - we sort of got all the pieces.

We should be able to get it all from here.

But it has never ever been true in the history of humankind yet

that we've had all the puzzle pieces.

So just imagine trying to understand something like the Northern Lights

before you understand what the magnetosphere is,

or how muscles work before you understand the concept of electricity,

or how the heart works before the concept of a pump was understood.

You would make theories, have all kinds of ideas,

but they would be doomed to be incorrect.

And we know that's the situation we're in.

First, there's all the stuff that we don't even know we don't know.

But the thing I want to emphasize

is that there's a lot that we know for sure we don't know.


So take for example the concept of dark matter.

So what happens is astrophysicists look out in the sky,

they look at the gravitational pull of everything they can see,

they figure out where it's supposed to be going,

and it turns out the equations don't quite work out.

So there's this fudge factor of dark matter

where you say, "Well, in order for the equations to work out,

we'll assume there's something out there we can't detect in any way -

we just can't see it, we don't know what it is -

but it must be there,

and it's causing all this gravitational pull that we can't account for.

But it's not a fudge factor exactly.

Ninety percent of the known universe is what we call "dark matter."


So what this means is we're sweeping a lot under the rug;

we know that there's a lot we don't understand.

And what I study every day when I go into the lab is this:

this is the human brain.

It's three pounds.

It's the most complex thing we have ever found in the universe.

It's made of hundreds of billions of pieces and parts.

They are connected in such density

that if you took a little cubic millimeter of brain tissue,

there are more connections in there

than there are stars in the Milky Way galaxy.

So it's an incredibly complex system,

and yet somehow this wet biological network is you.

It's all your hopes and aspirations and dreams,

every piece of love you've ever felt,

hunger, joy - everything.

This is you.

And the reason we know this

is because if you lose a part of your pinkie, you're no different,

but if you lose a piece of brain tissue of that size,

you're a completely different person.

It changes you; it changes your conscious state;

it changes who you are.

So we know that somehow you are this thing,

but what we do not know is how to take mechanical pieces and parts

and build it in such a way

so that there's private, subjective experience.

If I gave you a trillion Tinkertoys,

and I said, "Okay, put them together so this turns that and ..."

At what point do you add one more Tinkertoy and say,

"Okay, now it's experiencing the taste of feta cheese"?


So the issue is not only do we not have a theory of how the brain works,

we don't even know what such a theory would look like

because we don't have the tools to say,

"Okay, if you carry the two and you do a triple integral here,

that equals the redness of red or the feeling of pain."

Right? We don't know how to make that translation.

So these are the sorts of things that we know we don't know.

Okay, so I think all of this calls for a little bit of intellectual humility.

So, I was giving a talk on Possibilianism not so long ago,

and a guy came up to me after,

and he said, "Good job, Dr. Eagleman."

He said, "You know what?

You should be a politician

because you're avoiding committing to anything.

That's a great job for a politician."


And what he said was,

"You know what? You should just cowboy up and commit to some position."

So I thought, "Wow, well, that's a really strange idea," right?

It's a lovely expression that we have in this part of the country

about cowboying up,

which means making a firm decision.

And we all admire this sort of thing,

and I think it's really a great trait.

If you are making a decision about:

am I going to take the cattle out in this storm,

or am I going to marry this woman, or am I going to sell the ranch?

We admire people who make firm decisions.

But what I'm going to suggest

is that there are some domains where it's appropriate to do that

and some where there aren't.

So my question to you is,

Would you ask the Marlboro Man

what his opinion is on the possibility of extraterrestrial civilizations?

Would you ask him over, say, an astrobiologist?

And if you wouldn't, that suggests that there's a certain domain

where it's appropriate to cowboy up and make a firm decision,

and there's other domains

where it's appropriate to not commit to a particular idea

in the complete absence of evidence to do so.

So, I'm going to suggest that the next time somebody says,

"Well, you should just cowboy up and commit to a decision,"

we can say, "You know what? What I'd rather do is geek out."



And the idea with geeking out is,

I'm going to be creative and come up with new narratives;

I'm going to be comfortable holding multiple possibilities in mind.

And if you're going to geek out,

you should feel free to cite the gospel of science,

to tell the three words

that are the most important three words that science ever gave to humankind:

["I don't know"]


So my message to you is to go back out in the world today

and be comfortable with the idea of holding multiple hypotheses in mind.

And this is not just a plea for simple open-mindedness;

it's actually a plea

for an active exploration of new parts of the possibility space.

Because I think this is really important

for our educational systems for our children

and for our legislation,

and it's even important for our future of warfare

against other peoples of arbitrary deities and cultures

against whom we have historically been willing to take up arms, right?

So my plea is to leave this auditorium today

and go back into this strange mysterious world that we're in

and try to lead a life that is free from dogma

and full of awe and wonder

and to celebrate possibility

and to praise uncertainty.

Thank you very much.


The Description of TEDxHouston - Dr. David Eagleman