Practice English Speaking&Listening with: The Poetry of Science: Richard Dawkins and Neil deGrasse Tyson

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Without further ado, here's Professor Richard Dawkins and Dr. Neil deGrasse Tyson.

Well, Neil, we're here to talk about the poetry of science.

I would say that science is the poetry of reality, and one of the things that I feel

a bit humble in your presence, biology being a kind of junior science to physics, I suppose

we both have something to learn from each other; but I can't help feeling I've got rather

more to learn from you than you've got to learn from me.

Maybe we're both a bit naïve about each other's subject, but I think I'm a bit more naïve

about yours because there's more to be naïve about.

I forget who it was that coined the phrasephysics envy,” and I think this shows

itself in lots of fields, perhaps less so in biology than others, so what we're going

to try to do is to have a conversation between a biologist, an evolutionary biologist and

an astrophysicist, a kind of mutual tutorial without a chairman to get in the way.

I thought we might begin by noting that what we can see with our sense organs is an extremely

narrow band of what there is to see, and this is particularly so with the visual sense.

We can see a tiny, narrow band of the electromagnetic spectrum, the rainbow; but the rainbow's width

is tiny compared to the vast expanse of the electromagnetic spectrum.

I see that as a kind of symbol for how limited our understanding of the universe is, as well,

because after all, we are evolved beings who evolved to understand the interactions between

medium-sized objects moving at medium speeds.

And this ill equipped our brains to understand the very small quantum theory and the very

large, which I supposed is covered by relativity.

So, I find myself, as a mere biologist, baffled by some of the things that physicists talk

about, and jut to throw out one example, in the expanding universe, we are told (and I

have to believe it) that everywhere is as it were the same as everywhere else.

There's no one place which is the edge of the universe.

How can that be?

Well, Richard, first of all, you're told it so you have to believe it.

I will never require you to believe anything.

Good for you.

It will only ever be about how compelling is the evidence to you, but you started with

our sensory organs and landed in the expanding universe.

Can I take us back to the organs and then, perhaps, land in the universe?

Yes.

The urge to think of our senses as being powerful or good is strong because, first, that's all

we have; second, we like having nice thoughts about ourselves, rather than miserable, depressing

thoughts, so we're prone to talk around celebrating, for example the power of sight or of taste

or of smell, when of course, when you really smell something, you bring a dog, and they

smell...their nose smells much better than your nose smells.

I was going to say the dog smells better than you, but that would insult you.

So, we already know that our sense are feeble, and we reach to other creatures in the animal

kingdom, cite them as having better examples of our sight, of our taste, of our smell;

but little did people know much before a century and a half ago that our sense of vision is

limited only, as Richard said, to the colors of the rainbow, and it's quite extraordinary

to realize that, for example, beyond red, there's something called infrared; and beyond

infrared, there are microwaves.

And beyond microwaves, there are radio waves.

Go the other direction, you go beyond violet, ultraviolet.

Beyond that, x-rays and gamma rays.

Energy goes up as you approach gamma rays, with dramatic consequences if you have gamma-ray

exposure, by the way.

Of course, we all know you turn big, green, and ugly as The Hulk had experienced.

But the point is the visible light part of that spectrum is a tiny slice, and the universe

doesn't only communicate with us through that slice, as we had taken for granted for so

long.

Most of the history of the telescope, which is itself an extension of our eyes, extended

the power of our eyes but not the range of our eyes.

It wasn't until we first understood that maybe we're missing something in the 19th century,

the 20th century came decade by decade, new telescopes in each newly-discovered band of

light.

Only then did we learn about black holes in the universe or remarkable violent forces

operating in the centers of galaxies, discovered by radio telescopes.

So, yeah, we're practically blind out there, and it's humbling, by the way, but that's

the whole point of the methods and tools of science, to not only extend your senses in

the domain in which you understand, but to take them to places they've never been before.

On top of that, we have methods and tools that detect things that are not even extensions

of your senses.

You have no clue what the magnetic field is around your body right now.

You have no clue whether or not you're being bathed in ionizing radiation right now.

You'll eventually figure that out, as limbs start falling off; but while it's happening,

you actually don't know.

There are other things that are more subtle like polarization of light.

So when I think of the scientist's tool kit, especially the astrophysicist's tool kit,

it's all about how many different senses can you bring to bear, technological senses can

you bring to bear on decoding the universe.

One of the things we have discovered, now getting to your horizon question, we look

around the universe, and it looks like we're in the center.

What an ego-supporting concept that is!

You can either go around continuing to think that, feeling good about yourself, or study

the problem and learn that, in an expanding universe, where the speed of light is finite

at 186,000 miles per second...forgive me using miles per second...

I'd prefer miles.

You do.

You got that on tape?

An Oxford professor, I prefer...

No, it's true.

Nobody talks about kilometers in Britain.

Oh, good.

All right.

We share not only most of our language, we share miles still.

And inchworms.

What do they call them?

They're not centimeter worms, right?

They're inchworms.

We don't have that sort of stuff in Britain.

That's Europe.

Of course, Britain is not Europe, as we are constantly reminded.

That's right, here we have the English breakfast and the Continental breakfast.

They're very different breakfasts that you can order here.

So, this horizon problem is actually quite simple; and rather than explain the full up

nature of it, let me just give a simple example that is entirely analogous.

When you're a ship at sea, and you look out, your horizon in every direction is the same

distance from you.

It depends on your height above the sea level.

That's why ship decks are high.

They see farther beyond the curvature of the earth than you do just standing on the main

deck.

So, your horizon is a perfect circle centered on you.

You can conclude that is the extent of the entire earth, or you can imagine, suppose

I'm in another spot.

Well, that horizon is still true for whoever happens to be in the middle of it, but now,

you've moved to a new place, and you will see a horizon corresponding with that spot.

So, everybody has a horizon at sea; yet no one at any time is thinking that that's the

full extent of the ocean or the full extent of the earth.

We have a horizon in the universe, so does the Andromeda Galaxy, the galaxies with names

that look like phone numbers.

If you travel to those galaxies, they will see the edge of the universe now in three

dimensions in every direction at the same distance from them, just as we see for ourselves.

That does it for me, provided that the horizon is that which we are capable of seeing.

I could follow that if you said that, for any part of the universe, the horizon is the

bit before the expending universe has disappeared over the horizon.

Yes.

It's just no longer visible, but it's still there, even though we can't detect it.

That's true of the ocean when you're at sea.

Yeah, but...anybody on my side here?

You want it to be a harder problem than it is.

I'm just simply saying...

So, here you go.

Here you go.

The radius to our horizon is about 14 billion light years.

Got it.

Okay?

If we sat here or returned to this spot a billion years from now, that horizon will

be 15 billion light years away.

It's actually an expanding horizon because the light from 15 billion years, light years

away, will have had time to reach us.

Right now, it's still en route.

I have no problem with that, but beyond the 14 billion year...

The problem is the universe wasn't born yet.

Yes, okay.

That's the problem.

I know.

Okay?

So, you can't see the universe before it existed.

So why doesn't somebody...

...invent the kind of telescope that can?

No, no, no.

Okay, I'm getting out of my depth here.

Let's get back to...

Just to clarify.

It takes light time to reach us, and the universe hasn't been here forever.

You combine those two facts, you get an edge of the universe.

And so, the universe has been here for 14 billion years.

The farthest thing that could send us any information is 14 billion light years away.

I get that, but what about the guys who are on the edge of what we can see?

How can they see beyond the other side?

Oh, because...here's an interesting point.

They don't know whether or not the entire universe is infinite.

The universe could be twice our horizon or infinitely larger than our horizon.

Same with the ocean.

You don't know how much bigger the ocean is than your horizon is.

You can keep sort of wandering around.

Maybe you'll hit land as we've done, of course.

So, now you go there.

If the universe is really, really big, that will be the center of their own horizon.

And whatever is the age of the universe is, for them at that time, that will be the radius

to their horizon.

Yeah, okay.

I just want to make a remark.

You drew the analogy of the sense of smell, and what a poor sense of smell we have.

It's a fascinating fact that, although dogs, for example have a much better sense of smell

than we have, as you mentioned...

That's why I say sense of smell.

That's what I should say, not that dogs smell better, but they have a better sense of smell.

Thank you for that.

But we have the genes that would have once enabled our ancestors to have as good a sense

of smell as dogs, but the genes have mostly been turned off; so we have vestiges.

We have historical relics of those genes.

It's like your hard disk on your computer that's cluttered up with remains of old chapters

you've written here and there and things that have now been cut off.

Those genes have been turned off, but they're still there.

Isn't that the premise of X-Men?

I don't know.

They're human, but they have a genetically different...different genes are turned on

and off within them, giving them special powers.

So, are you suggesting the day might arise, we go inside the human genome and flick the

dipswitches on and off, and we come out as superheroes?

Put it this way.

It's not as unlikely as it might have appeared before we realized that we do have those genes

still.

You don't have to import the genes from dogs, although the technology of this coming century

may enable that to happen.

I'd still rather it be the dog that sniffs the bomb than me.

But we would probably have robots to do the sniffing.

What about this point about the difficulty of...maybe I chose too easy an example.

The brain, how is it that the human brain, which evolved to do really rather mundane

things...

...to not get eaten by lions.

To not get eaten by lions in the Pleistocene of Africa because, as you'll learn this evening,

we are all Africans.

We all come from Africa, and our brains were shaped by natural selection on the African

plains to do things that involve objects like this.

Medium-sized objects.

Macro-sized objects.

Macro-sized objects that don't move anywhere near the speed of light.

It's a tremendous tribute to our species that we are capable...at least some of us are capable...of

understanding things that don't belong on that ordinary macroscopic, slow-moving scale.

Yeah, and so therein is the value to us, not only of the methods and tools of science,

but also of the language of the universe that we call mathematics.

Remarkable thing, a point first advanced by Eugene Wigner that math has an unreasonable

utility in the universe since we just invented it out of our heads.

You don't discover math under a rock, as you might find grubs.

You invent it out of whole cloth, yet is empowers us to provide accurate the predictive descriptions

and understandings of the universe.

So, what comes of this is you learn to abandon your senses.

That's a like from the Broadway musical Phantom of the Opera...abandon your...never mind,

sorry.

I want to write Broadway lyrics one day in another life.

You train yourself to abandon your senses because you recognize how they can fool you

into thinking one thing is true that is not.

You abandon them.

You use your tools that do the measuring to say, okay, that's the reality.

Then you make a mathematical model of that that you can manipulate logically...because

math is all about the logical extension of one point to another...and then you can make

new discoveries about the world that, frankly, you'll just have to get used to you.

No longer do you have the right...right is not the right work, but no longer are you

justified saying that idea in science is not true because it doesn't make sense.

Nobody cares about your senses.

Your senses came out...forget the Serengeti, just growing up.

As a kid, something's in your hand, you let go of it, it falls.

You tip a glass, water spills.

You are assembling a rule book for how nature works in the macroscopic world.

The microscope takes you smaller than that; the telescope takes you bigger; and the other

laws of physics manifest themselves in those regimes that you have no life experience reckoning.

It's math that allows you to take these incremental steps beyond the capacity of your senses and

perhaps even the capacity of your mind.

Yes, it's the mind that's taking the steps, but your mind was not deducing that by just

looking at the world with your senses.

It was helped out.

It was aided by these tools that, yes, we invented.

And at some point when you get so used to doing the mathematics, it becomes kind of

intuitive in rather the way that I'm told that pilots get used to flying a plane, and

they start to feel the wings of the plane as being almost part of their own bodies.

They develop...

Before or after the drinks before they took off?

Is this a common sensory perception of pilots.

Yeah, I think it is.

It's a common thing that I think that, when people get skilled at using micromanipulators

where they're using their hands, and what actually going on is tiny little miniscule

movement going on under a microscope...

...so it becomes their hands.

It becomes their hands.

The plane becomes the pilot, or the pilot becomes...

Just as you said, the telescope is an extension of the eyes.

My advisor in graduate school...one of my advisors, I spoke to him one morning.

He was doing research on star clusters that have these huge orbits around the center of

the galaxy.

He said he had a dream the night before where he was one of these clusters, and he was orbiting

the center of the galaxy.

I thought that was so cool.

Yes, yes.

If you start becoming in your cosmic dream...I want to have those dreams because then, you

think creatively about what remains to be discovered.

Absolutely.

I sometimes wonder about whether surgeons, maybe even surgeons of the present who are

using micromanipulators inside a body, something like when they stick that thing up you, and

it goes...

They stick a lot of things up you, the last I've heard.

Okay, and already you have surgeons driving an endoscope inside and turning left to get

round the intestine, turning right.

I imagine the time will come when a surgeon will have virtual reality goggles on, and

the surgeon will actually feel herself to be inside the body of the patient and will

turn left and literally walk across the room, and that will be translated into the micromanipulators,

the endoscope, moving.

This sounds really cool.

I like this idea.

And you know what you'd have to do?

You would have to alter the dominant laws of physics in that regime because, if you're

small enough a la Fantastic Voyage, the 1960's film, when you're that small, capillary action

and surface tension and all manners of other forces take over and that then becomes your

new reality, your new sensory standards.

That's right.

You would have to become sensitive to surface tension.

D'Arcy Thompson made the point, I think in 1919, that to the world of an insect, gravity

is negligible.

A completely...it's who cares?

What matters is surface tension, and you'd have to be...I never thought of that, but

what I'd do...

That's because you didn't see the move Bug's Life, okay?

Okay.

In Bug's Life, they serve up a cocktail to an insect that goes up to a bar, and all the

bartender does is pour out water from a spigot and hand him the ball of water, like that,

and the surface...this was brilliant of the cartoonist, of the illustrator, and then,

he sticks a straw into the sphere and sucks it out.

No receptacle needed.

You got to get out more.

Well, I imagine my surgeon of the future being armed with a virtual saw, one of those...what

are those things you cut trees down with...band saws, and what's really going on is a tiny

little micro scalpel inside, but the surgeon is wielding an axe, and it's all done by virtual

entity.

I've got a question back to you.

I lose sleep over this, and I've always wanted to be in the company of a leading biologist

to get insight into this.

As an astrophysicist, we've seen throughout time the hubris that comes with any discovery

that gets made, or the hubris that prevents the acceptance of a discovery that might demote

your sense of self from whatever you previously imagined it to be.

Among them is where is earth?

Is it the center of all things?

No.

It's not even a significant planet in orbit around an ordinary star in the corner of an

ordinary galaxy, one of a hundred billion galaxies in the universe.

And so, here we are saying let's search life in the universe, intelligent life like us.

Well, who are we to say that we're intelligent?

I pose that not as a joke questions, but as a very serious question.

We define ourselves to be intelligent in ways that no other creature can rival.

Okay, now, what do we credit that intelligence to?

So, you look at the genome, and let's take the chimp.

I guess that's a really close relative of ours, and we have...what is it?

High 90's percent identical, indistinguishable DNA, and the chimp does not build the Hubble

telescope, and the chimp does not compose symphonies.

So, we must then declare that everything we say about us that is intelligent is found

in that one-and-a-half percent difference in DNA.

First, is that a fair statement to make?

Yes.

Okay.

Let me invert that question.

If the genetic difference between humans and chimps is that small, maybe the difference

in our intelligence is also that small.

Maybe the difference between stacking boxes and reaching a banana, putting up an umbrella

when it rains, whatever are these rudimentary things a chimp does that the primatologists

roll them forward and boast about, which of course, our toddlers can do, maybe the difference

between that and the Hubble telescope is as small as that difference in DNA.

I pose the question: suppose there was another life form on earth or elsewhere that, in that

same sort of vector, that one-and-a-half percent difference we are to chimps, suppose they

were one-and-a-half percent different from us?

Then would then roll the smartest of us in front of their hematologists and say, Hawking,

there's Hawking.

Oh, this one is slightly smarter than the rest of them because he can do astrophysics

calculations in his head.

Like little Timmy over here.

So, I wonder if we're just blithering idiots in the presence of even a trivially smarter

species than us.

Therefore, who are we to even assert that, number one, we are intelligent, and we're

looking for others at least as intelligent as us out there to talk to.

By the way, is there any other species on earth that we can talk to?

Can we have a conversation with a chimp?

That has identical DNA, and I don't think we can actually say, hey, what movie do you

want to see tonight?

You don't have that conversation with a chimp.

Yet somehow, we believe, we want to believe that an alien on another planet that's not

even based on DNA and, even if it is, it's not nothing like us, that we could communicate

with it.

I'm screaming at you.

I'm sorry.

So there!

Are we as stupid as I'm saying?

Well, I'm all for deflating hubris; but it's also true, of course, that our brains are

anatomically very, very much bigger than chimps, and so that also must be contained in some

sense in that tiny little percentage of DNA.

I think the way to sort of look at the DNA problem is to say that the sort of DNA that

has been sequenced, and the sort of thing on which we base that calculation of the 98

percent...again, look at a computer, and you will find that most of the programs that are

written at the machine code level are calling out the same set of subroutines.

There's a subroutine for pulling down menu bars and a subroutine for moving windows and

so on.

That's what we're looking at in this 98 percent.

What we're not looking at is the set of sort of high-level instructions that say call this

subroutine now, now call this one, now call this one, now call that one.

It's not just humans and chimpanzees; all mammals have pretty much the same repertoire

of genetic subroutines.

The difference between a man and a mouse, like the difference the difference between

a man and a chimpanzee is the order in which they're called, the sequence in which they're

called during embryology which causes the really quite substantial anatomical differences

between a human and a mouse and the quite big differences in brain size.

If we assume we're not some measure of things, then as I said earlier, that tells me that

the day might come where we could go in, understand which sequences are called in what way, and

invent whole new sequences never before dreamt of by biology?

Yep, absolutely.

Empowering us in ways never before...

It's very, very difficult.

It's much more difficult than it sounds; but still, it's in principle possible.

But the other point about intelligent life in the universe, never mind how we define

intelligence.

We're only going to encounter them if they are intelligent enough either to come here,

which is very difficult indeed, or to send radio transmissions to us, which is a lot

easier but still requires...let's just define it as the quality that you need in order send

information across the universe.

Now, you don't have to call that intelligence, but whatever it is, that's what it needs in

order to get here, in order for us to apprehend it.

And I wonder, you know, surely you've walked past a worm that had just crawled out of the

earth; and when you did so, you weren't saying to yourself, gee, I wonder what that worm

is thinking because you just simply didn't care.

You're so far beyond the...I don't want to put words in your mouth, but I'm imagining

you simply really don't care what the worm is thinking; and conversely, the worm has

no clue that you consider yourself intelligent.

You're just this thing that went by.

So, can you imagine a species that has such high intelligence that the prospect of communicating

with us is simply of no interest to them?

Yeah, I can.

Yeah.

And they go by, and their intelligence is on such a level that we can't even recognize

it as intelligence.

Yes.

Moreover, I think it would more or less have to be that much ahead of us if we were ever

to meet them because we're never going to get there.

Yeah, we sure as hell ain't getting there.

See the massive budget lately?

If not...

So, anything that gets here has got to have a very, very highly-developed technology,

far more than we've...

That brings us to Stephen Hawking's concern about any civilization sufficiently advanced

to visit us, what does that say about the consequence of that encounter?

And he's worried, of course, because he's taking his cue from the history of humans.

When one has a more advanced technology than the other, and they visit, it almost is always

bad for those with the lesser technology.

South America, one of the more obvious examples, in their first encounter with the Spaniards...so,

I don't know if I want to be the first one to shake hands...shake whatever appendage...whatever

they're sticking forward, I don't know...

I want to do it, but I still have my concerns.

What do you think are the odds that there is life elsewhere in the universe?

They must be high, and I'll tell you why.

People say, well, have you found life yet?

No.

Well.

That's like going to the ocean...this has been said before...taking a cup of water,

scooping it up, and saying there are no whales in the ocean.

You know?

Here's my data.

You know?

You need a slightly bigger sample.

If you look at, for example, what we call the radio bubble.

This is the sphere around earth, centered on earth, which is the farthest our radio

signals have reached in the galaxy.

They're about 70 light years away.

We've been transmitting radio signals, inadvertently leaking into space, for about 70 years.

Seventy light year radius sphere.

Well, how big is the galaxy?

Well, shrink that sphere down to maybe the size of a BB, and then, the galaxy, on that

scale, would be the size of this stage.

That's how far our radio signals have traveled, and those aren't even the ones we sent on

purpose.

The ones we sent on purpose have traveled much less.

So no, we haven't actually reached as far into the galaxy as we'd like before we would

say definitively that there's no one intelligent living today.

But here's some very simple facts.

I can review them in 90 seconds.

You look at the formation of the earth and the earliest sign of fossil life.

Subtract a few hundred million years at the beginning of earth when earth was a shooting

gallery, earth was still excreting the birth materials of the solar system.

It's hostile to complex chemistry over that time; not fair to start the clock then.

Wait a couple of hundred million years.

Now start the clock, and wait around and see when you have the first signs of single-celled

life.

At most, 400 million years.

At most.

Earth has been around for four-and-a-half billion.

So earth, without any help from us, with basic ingredients found throughout the universe,

managed to create life, simple though it was.

And earth, one of eight planets...get over it...sorry.

Earth around an ordinary star?

To suggest...and what are the ingredients of life?

The number one atom in your body is hydrogen.

Number two atom is oxygen, together making mostly water that's in you.

Next is carbon in this order.

Next is nitrogen.

Next is other stuff.

My favorite element, other.

Yeah?

You look at the universe, the number one element in the universe is hydrogen.

Next is helium, chemically inert, couldn't do anything with it anyway.

Next is carbon.

I think I left out oxygen there.

Next is oxygen.

Next is nitrogen.

One for one.

We're not even made of odd things.

The most common things in the universe are found here on earth, and we're made of them.

And carbon?

The most chemically fertile element on the periodic table?

It's not a surprise we're carbon-based.

Life is just the extreme expression of complex chemistry.

That's what biology is.

All these people who want to imagine, because they remembered the chemistry class that silicon

sits right below carbon on the periodic table, so it bonds similarly to carbon, so they want

to imagine silicon-based life.

I'm saying, okay, fine; but you don't have to.

There is five times as much carbon in the universe as silicon.

There's no need to even have to go there.

We've got enough to imagine just simply with the carbon atom at the center of these huge

biological molecules.

Point is, it happened relatively quickly with the most common ingredients in the universe.

To now say life on earth is unique in the universe would be inexcusably egocentric.

Yeah, I agree with that; and I would go further and say that, if ever you meet somebody who

wishes to claim that he believes or she believes that life is unique in the universe, then

it would follow from that belief that the origin of life on this planet would have to

be a quite stupefyingly rare and improbable event, and that would have the rather odd

consequence that, when chemists try to work out theories, models of the origin of life,

what they should be looking for is a stupendously improbable theory, an implausible theory.

If there was a plausible theory of the origin of life...

...it wouldn't be it.

That's right because then life would have to be everywhere.

Now maybe it is everywhere.

My hunch is that there's lots and lots of life in the universe; but because the universe

is so vast, the islands of life that there are are so spaced that it's unlikely that

anyone of them will meet any other, which is rather sad.

It's sad.

However, let me make you happy a little bit more from that.

We've learned now that we can model the formation of the solar system, and this period of time

where earth was being bombarded heavily...that's called the period of heavy bombardment in

the early universe.

We call it like we see it in astrophysics, let the record show.

I don't know if I've ever in my life ever understood the title of a biology research

paper.

I just want to say that.

The words just...I'm not feeling them, you know?

They're too big, too many syllables.

I'm off topic here, so...

The period of heavy bombardment and, with computer simulations you can model what happens

when an impact hits a planetary surface.

It's not much different from if you sprinkle cheerios on a bed, which you would never do

on purpose, but your kids would do this; and then, you smack the surface of the bed, there's

a sort of recoiling effect, and cheerios pop upwards.

It turns out Mars may have been wet...we know at some point, it had water...and fertile

for life before earth.

At this period of heavy bombardment, if it had started life, surely it would have been

simple life.

There's no reason to think otherwise.

We've learned that bacteria can be quite hardy, as you surely know.

So, we imagine a bacterial stowaway in the nooks and crannies of one of these rocks that

are cast back into space.

In fact, if you do the calculation, there's hundreds of tons of Mars rocks that should

have fallen to earth by now over the history of the solar system.

Maybe one of those rocks carried life from Mars to earth, seeding life on earth.

My great disappointment would be going to Mars and finding Mars life based on DNA.

Then it would not have been a separate experiment in life.

We would just all simply have to get over the fact that we are Martian descendants.

What we need is a second sample of life.

We have only one at present.

Why have you only given us one?

It would be a disappointment, as you say, if we found life on Mars based on DNA; but

at least, if we found life on Mars based on the same DNA code, just about imagine DNA

evolving twice, but you couldn't imagine the same four-letter code evolving twice.

But I wanted to make a point that your calculation that it took only about 400 million years

at the most for the first life to arise.

For the first life capable of broadcasting radio waves capable of being detected elsewhere

in the universe, it took approximately just under four billion years.

Well no, about four billion years, which is about half the life that we can expect the

solar system to exist.

Sure.

An important point, by the way, because we were human before we had the technology to

broadcast.

So if your criterion for whether a planet has intelligent life, and if we are the measure

of intelligence, then there could be plenty of planets out there with Roman Empires and

whatever else and them not sending radio signals; but any close enough observer would surely

declare them to be intelligent.

The time interval between Roman Empires and radio signals is negligible compared to the

total time we're talking about.

It's an interesting question, how long it takes once you get language, once you get

civilization, once you get culture, how long does it take to get radio waves?

Indeed, how long does it take to get self-destructive weapons that blow the whole lot up?

That's the next...

And you're even...there's an implicit assumption, that you're making inadvertently possibly,

that intelligence is an inevitable consequence of the evolutionary record, and I'm skeptical

of that because, if that were the case, what we call our intelligence would have happened

multiple times in the fossil record, and it hasn't, whereas other things have shown up

plenty of times, like the sense of sight and locomotion.

There's some rather inventive ways things can get around the world.

My favorite is the snake, of course; no arms, no legs, yet it gets around just fine.

I'm imagining an alien visiting earth, stumbling on a snake, the only creature it sees, right?

And then, it goes back and tells its home people, you're not going to believe what I

saw.

There's a creature on that planet, no arms, no legs; it can still get around.

It detects its prey with infrared rays and can eat things five times bigger than its

head; and they'll think the guy was on drugs.

It's an ordinary snake, sitting here on our earth.

While I'm on the subject, a big disappointment I have are Hollywood aliens, and I don't know

who to blame for this, Hollywood or biologists that advised them.

Hollywood aliens are way too anthropomorphic for me.

Even ET, he had a head, shoulders, arms.

Okay, he had three fingers instead of five; they're still fingers at the end of a hand.

He had legs; he had feet.

That's human.

And look at the diversity of life on earth to draw from?

If you want to think about the ways of being alive?

I'm just so disappointed.

Not even that I know I can help them, but one of my favorite aliens ever was the Blob.

Did you see that movie?

No, I don't see as many movies as you.

Blob is classic.

So, that alien was a blob.

That's what it was.

And it would just kind of move along, and it would grab onto you and suck out your blood,

and keep moving.

It was non-anthropic in concept, and it came from space.

I just thought that was an attempt to try to create some kind of way of being alive.

That's a very laudable attempt.

It is very interesting to look around the animal kingdom and count up the number of

times that some things have evolved.

I mean, eyes several dozen times; ears quite a large number of times.

Echo location, that's finding a way around by sonar, only four times.

A bat and who else?

A bat, whales, and two different groups of birds, cave-dwelling birds.

And a few rudimentary examples in some shrews and sea lions, but really four different times.

Intelligence and language of a human kind, only once, as you pointed out.

So, it can't be that important for survival.

If natural selection is at work, it should have shown up many more times.

You'd think so.

It's a genuinely interesting point that I think biologists haven't thought about enough

is to go around the animal kingdom, counting up the number of separate arisings of something

because that does tell you something about what you might expect elsewhere in the universe.

You'd expect eyes.

You might expect echo location.

Hypodermic syringes, stingers.

About a couple of dozen...I'm talking about independent evolutions now.

You talk about spiders...

Our version of that would be called guns.

Yeah.

What?

Our version of the hypodermic stinger would be called a gun, allowing you to sting someone

with...

Yes, okay.

But I'm talking about it as something that penetrates the body and injects poison.

That's an interesting question.

Another relevant point is look around the world at different island continents and say

how similar are they?

Look at Australia.

The Australian mammals, for example; and there are very, very power similarities between

Australian mammals, which evolved entirely independently of mammals in South America,

independently again of mammals in Asia and Africa.

Again, that gives you a kind of a clue for how predictable evolution is.

Other worlds are going to be very different, but we perhaps shouldn't write off the possibility

that the Hollywood aliens might not be that unimaginative.

I mean, my colleague Simon Conway Morris has even suggested that it's very likely that

there will be, if not humans, at least bipedal, big-brained, language-toting, hand-toting,

forward-looking eyes for stereoscopy, pretty much humans.

He thinks it's highly likely.

He's got a religious agenda, I'm sorry to say, for that; but like him, I appreciate

the power of natural selection.

By the way, I think if he were a creature other than a primate, he might be giving a

different list of things that matter.

I think that's probably right.

The horse doesn't have two eyes facing forward, but the horse damn near can see directly behind

it; and so, the horse would be valuing that fact.

Oh, I'm not denigrating horses at all.

I'm just saying your first sign that there's bias is you start listing the human features

that you would want in an alien.

No, no, no.

I don't want to say that I'm not picking on humans because they're superior but because

they're us.

I mean, we have stereoscopic vision.

We have three-dimensional vision.

Horses don't.

They have a different kind of vision.

Insects have a different kind of vision.

Bats have echo...I mean, it's not vision, but it's using sound to produce what I would

guess inside the bat's brain is probably perceived rather the same way we perceive visually because

why wouldn't you use the tools of the brain, the mammalian brain to create an image, to

create a model of the world.

They show that in the, forgive me, movie Daredevil.

Do they have bats...?

He's blind, and he likes when it rains because the rain hits people, and he hears the different

sort of reflections of the sound, and he saw his girlfriend for the first time in the rain.

There's the image of her...

Okay, but my speculation is that bats hear...

This is America.

I've got to talk about our movies here, you know.

My speculation is that bats hear in color because why wouldn't you use color?

Color is just a hue, a perceived hue.

It's nothing more than a label the brain uses.

Precisely.

That's all it is.

Color, you attach it to some sequence of changed phenomenon.

So, bats would usefully use color as a sign.

For example, if you're between a furry moth and a leathery locust, it might be perceived

as red versus blue, and that would be a very useful way for natural selection to have tied

the labels of hue onto something that would seem very strange to us.

We're coming to the end of our time.

Did we just begin, like a second ago?

Well, that's rather what I felt.

If we want to have some time questions...

...which I would very much like that, but I had a couple more bones to pick with you.

Okay, well, let's go quickly through those bones.

Okay.

And if you start formulating questions in your head...

Some years ago, 1994 was it?

Or 1996, there was this rock in Antarctica, a meteorite discovered ALH84001, which had

tantalizing evidence...by the way, that rock was from Mars, one of the tonnage of rocks

that we know are out there, and there was evidence in one of the nooks of that rock

for possible life, traceable not to earth but from Mars.

The evidence was very circumstantial but interesting, nonetheless.

There was chemistry there that could only happen in the presence of oxygen, and there

was chemistry there occupying a similar spot that could happen only in the absence of oxygen.

Well, you might say who cares?

Well, life is just such a machine.

When you breathe in oxygen, you oxygenate the hemoglobin, that oxygen gets used for

your metabolism, and it goes back without the oxygen.

In the same body, you have oxygenating and deoxygenating forces operating within you.

So, life does it for free.

If you don't appeal to life, you have to have the rock hang out over here for a while and

then roll down a cliff and go anaerobic for a while.

You have to sort of patch it together.

So, it was all the news, page one story.

They even had an electron microscope photo of what looked like an itty, bitty worm.

It had little segments on it.

It was intriguing.

That was not the lead evidence of the authors, it was just kind of interesting.

It was about one-tenth the size of the smallest worms on earth but interesting, nonetheless.

I'm invited to comment on this.

In fact, it was Charlie Rose.

He had four people.

I'm the astrophysicist.

They had a biologist.

They had a philosopher.

And a picture of the worm comes up.

The biologist, who is piped in by screen said, “That can't possibly be life.”

So, I said, wow, what have I missed?

So, tell me, sir, why is that?”

Oh, because the smallest life on earth is 10 times that size,” and I'm still waiting

for him to give me the reason why it can't be life.

Then I pause and reflected at that book.

That is the reason he's giving me that it can't be life...his comparison with life on

earth.

And then I said, “Last I checked, we're talking about a rock from Mars.

Why are you using earth to constrain your capacity to think about what exists out there?”

My question to you: are biologists closed-minded or open-minded about what is possible in terms

of biology in this universe?

Because at the end of the day, you go behind closed doors, and you confess to yourselves

that you only have a data sample of one because all life on earth has common DNA.

Yeah.

Well, he was being closed-minded.

Most any other sciences, we would say that's not...how do you make science out of a sample

of one?

No, that's right.

He was being closed-minded, no question about it because he was using his experience of

life on this planet to make that generalization.

On the other hand, one could make sure a statement by using the laws of physics, and you could

say that there are certain things that wouldn't work for physical reasons.

I'm not saying that a tiny worm wouldn't work for physical reasons, but I could imagine

somebody making an argument that said you cannot have...for example, maybe there's a

certain minimum size of eye that could form an image, for purely physical reasons.

That would be a good reason why.

And I'm there, all the way.

It's just that he cited earth as his measure of what is possible.

Well, he was just wrong.

Okay.

You don't align yourself with his closed-mindedness.

That was the biggest thing I had to get off my chest here.

Okay.

Shall we bring up the lights, and see if there are...

Are there microphones...?

In the aisle apparently, so if you'll just line up in the two center aisles behind those

microphones.

I guess we can pick left and right for what questions you might have.

Professor Dawkins, we're very pleased to hear that you're writing a children's book on the

beauty of science.

We'd like both of you to write one for adults or a video special on TV because we don't

want this wonder and awe that you all have been discussing today to be co-opted by religious

people in the world, and it is really wonderful.

What can we do to spread the word that science is not something to be afraid of, but something

to really be in wonder of?

Right.

Can I just slip in there?

You commented that there's a children book, and we need one for adults.

Indeed, we need one of those for adults.

Interestingly, we probably don't need it for children because children are born inquisitors

of their natural world.

They turn over rocks.

They jump in puddles.

They pour water down your back.

They do things that are odd by...you can look at it as wreaking havoc in the house, or you

can look at it as a long series of science experiments, some of them gone playfully wrong,

but nonetheless, explorations into the natural world.

What happens is, over time, that gets beaten out of them because that is not the behavior

of...not the sign of obedience.

That's the behavior or disarray, plus adults far outnumber children, so I think the real

problem in the world is adults, especially since they control the world, not the kids.

What I would say about how we convey the wonder, which you and I are both extremely interested

in doing that, and following your mentor Carl Sagan, for example.

I like to make a distinction between what I call these two schools of why we should

pursue the space race, space exploration.

The nonstick frying pan way, which is it's useful because you get spinoffs like nonstick

frying pans, and it's wonderful.

I go for the wonderful part, and I find that one of the problems with people who attempt

to convey science to lay people, whether it's children or adults, is that they tend to be

obsessed with bringing it down to earth and making it ordinary and mundane and the sort

of thing you might meet in your own kitchen.

I'm glad somebody's doing that, but for me, I prefer the wide open spaces of space, the

wonder of looking down a microscope at the very small and thinking about it from a sort

of more poetic point of view rather than from a more utilitarian point of view.

Hi.

First, I'd like to say thank you.

This is very stimulating, and it's wonderful to have this here at Crampton Auditorium,

at Howard University.

I have a practical application question for technology and its impact on humans, specifically

cell phones, cellular cell phones.

I'm in healthcare, and I'd like to know where you stand on the effects...and I know we've

come a long way since the first cell phones came out, but I get particularly apprehensive

when I see young people putting cell phones to the heads of little infants and saying,

Talk to Daddy,” or something like that.

That's my first question, the impact of the waves and things like that, which is out...I've

look at some studies on human beings.

Then, my second question is about the references for the origins of calculus in the Egyptian

culture.

Thank you.

Okay, given how many people are in line, I think we should try to answer as quickly as

possible to do this, and I'll take a first stab, and if you want to try that as well.

I don't know of any first efforts at calculus in the Egyptian culture.

Perhaps Richard does.

And with regard to cell phone use, there's a very important fact of science, and that

is the active measurement...it's a fascinating thing, measurement.

Because you can never measure anything precisely, that is, with unlimited precision.

You can only measure it with the uncertainties of your measuring device.

And all you can do in the lab is try to constrain how uncertain that measurement is; but at

some level, it will always be uncertain.

And here's what happens.

If you're trying to measure a phenomenon that does not exist, the variations in your measurement

will occasionally give you a positive signal, as well as a negative signal.

If that positive signal is the idea that maybe A causes B, in this case, cell phones cause

cancer, a paper gets written about that result, and then, people get concerned that cell phones

might cause cancer or power lines might cause cancer.

This goes way back.

In fact, if you look at the full spate of these studies, even those that they fought

not to publish because there was not a positive effect, there are some cases where, in fact,

there is less cancer.

And so, these are the phenomenon of a no result.

When you actually have A causing B, the signal is huge.

It is huge, and it's repeatable in time and in place.

With cell phones, that repeatable signal is yet to emerge from the total experiments that

are done on it.

That being said, if you are worried, almost every cell phone you can have...you know,

they have the cell phones on your hip, and you've got an ear piece, so just do that if

you're worried.

Otherwise, I can either say the jury's still out, or the experimental results are consistent

with no effect at all.

I have nothing to add to that.

About the calculus in Egypt...

Can we have this one now?

Yes, I was interested when you were speaking about the bubble of radio waves, as far as

the limitation of our communication.

I read recently that the Large Hadron Collider had some crazy experiments, but there apparently

are particles that are seemingly unconnected but they react to each other in symmetrical

patterns of some kind.

I'm very amateurish on this, but what do you think would be the possibility of instantaneous

communication across vast distances using some kind of particle manipulation?

That's exactly an example of the kind of thing I meant when I said it's beyond me, so...

Yeah, so quantum physics is the physics of the world of the small.

In fact, quantum rules apply macroscopically, but they don't reveal themselves as exotically

as what happens with single particles.

A particle can pop into existence, go out of existence, what we call tunnel from one

place to another, instantly, with no time delay between the two.

It could exist in all places at once and then show up instantaneously here when you make

the measurement.

These are quantum rules that don't make any sense to us because we don't live in a quantum

world.

If we did, these would be phenomena that would be quite natural.

So now, can we exploit the quantum world for faster-than-light communication is what you

are suggesting here; and there's no known way to do that, given the laws of physics.

In other words, you can have what's called a wave form, a wave function of a particle,

and it's everywhere.

You make a measurement, and the particle instantly shows up here, even though the wave had a

probability of existing...the particle had a probability of existing over here.

And so, it's just odd, and we don't know how to exploit that fact to our advantage; but

as far as we know, no, you cannot have faster-than-light communication, which we would desperately

need to get bigger than the bubble to talk to the rest of the galaxy.

Again, I'll try to make my answers even shorter than that.

Making the distinction between life in the universe, which I think is inevitable, and

intelligent life in the universe, which I question or challenge at least the probability

of, given our planet being in the right location, the star being the right type of star in the

right location, etc., what are the odds that you would...and given the time it took, four-and-a-half

billion, 4.6 billion years...for us to get to the point where we can ask the question

is there intelligent life in the universe.

What do you think those odds are?

The universe is huge, in time and in space and in content.

So, the good thing about the universe is extraordinarily rare phenomena happen every day someplace

in the universe.

So however rare we might calculate it would be here for life as we know it, you multiply

up the numbers...stars in the galaxies, galaxies in the universe...these are staggeringly huge

numbers, 1021 stars, 1,000 times bigger than the number of grains of sand on an average

beach, itself 100 times bigger than the number of words ever spoken or uttered by all humans

who have ever lived.

These are staggeringly large, stupendously large numbers, to use Richard's word, that

give us the confidence that, even if intelligent life is only short lived, grows up, and then,

grows so smart it kill itself, that there's bound to be one out there that we're hitting

it right at the right time that they are happy to have a conversation with us, if we're smart

enough to have a conversation with them.

This question is primarily for Professor Dawkins.

I come from a family where there are two skeptics and three religious fruitcakes.

You can guess which side I'm on.

Anyhow, I was just wondering, with your experience, if you've ever found a good way to hit the

fruitcakes upside the head with some rational thinking and actually get them to pay attention.

It would be nice to say that all we need to do is to expose them to scientific evidence,

and that's certainly a very important part of it is what Neil and I both are trying to

do.

Unfortunately, there's a certain amount of evidence that there's a certain kind of mind

which is so dyed-in-the-wool wedded to a scriptural version of the world that they more or less

admit in advance that, no matter what evidence comes, they will refuse to budge.

My favorite example of this is the geologist Kurt Wise, who is a young earth creationist,

but who knows very well all the evidence for an old earth from geology.

He has actually said, in these very words; I think I quote him approximately right, “If

all the evidence in the universe pointed to an old earth, I would be the first to recognize

the evidence, but I would still be a young earth creationist because that is what Holy

Scripture tells me.”

Somebody who's actually prepared to come out and say that, and at least he's honest...somebody

who actually comes out and says that is pretty much advertising himself as beyond reason.

He's absented himself from the rational discussion which the rest of us are having by announcing

in advance that scripture is going to take precedence over evidence.

And here's a man who knows the evidence.

He has a Ph.D. from Harvard in geology.

He knows the evidence, and yet, he's announced in advance, so there are certain people who

are unreachable; but my hope is that the vast majority of people are imminently reachable

and just simply haven't been exposed to the evidence which is plentiful and wonderful.

Next question here.

Thanks for the great job on the Poetry of Science.

I wonder if you could say just a few words, both of you, on the philosophy of science.

I just read Stephen Hawking's book, The Grand Design.

The first page, philosophy is dead; and here at Howard, our administration is proposing

the abolition of our philosophy programs.

Could you say a few words?

I have a couple of words to say about that.

Up until early 20th century, philosophers had material contributions to make to the

physical sciences.

Pretty much after quantum mechanics, remember the philosopher is the would-be scientist

but without a laboratory, right?

So, what happens is the 1920s come in.

We learn about the expanding universe in the same decade as we learn about quantum physics,

each of which falls so far out of what you can deduce from your armchair that the whole

community of philosophers that previously had added materially to the thinking of the

physical scientist were rendered essentially obsolete at that point.

I have yet to see the contribution...this will get me in trouble with all manner of

philosophers, but call me later and correct me if you think I missed somebody here, but

philosophy has basically parted ways from the frontier of the physical sciences, when

there was a day when they were one and the same.

Isaac Newton was a natural philosopher.

The work physicist didn't even exist in any important way back then.

I'm disappointed because there's a lot of brain power there that might have otherwise

contributed mightily, but today simply does not.

The philosophy has other...not that there can't be other philosophical subjects.

There's religious philosophy and ethical philosophy and political philosophy, plenty of stuff

for the philosopher to do, but the frontier of the physical sciences does not appear to

be among them.

Even in biology, I think, is an interesting point that the idea of evolution by natural

selection, which came independently to two traveling naturalists in the 19th century.

It's a simple enough idea that any philosopher could have thought of it from the depths of

an armchair anywhere back to the Greeks, and none of them did.

I don't really understand that.

It seems to me to be a strange thing that it had to wait to 19th century scientists,

living 200 years after Newton did something that seemed a lot more difficult.

Check Anaxagoras, first theory of evolution in pre-Socratic Greece.

Oh, well, okay.

But natural selection is something that came in the 19th...not just to Darwin and Wallace.

I mean, there were a couple of other scientists who thought of it.

The philosophers that I really respect in the world today are philosophers of science,

are ones who have actually taken the trouble to learn some science, and there are some.

And they're very good, clear thinkers, and they do help other people to think clearly;

but they're really the same as scientists.

There are scientists who are also trained in philosophy.

Sir.

Thank you both for coming.

There's a group of scientists in Europe that have developed a Large Hadron Collider, and

they're trying to recreate the conditions of what has been known as the Big Bang, slamming

antiprotons and protons to try and find a particle known as the Higgs boson, which has

been misnamed the God particle.

It's a particle that gives matter mass.

Could you guys talk about the conditions of the universe at that time?

Will this prove anything?

This experiment?

The interesting thing about physics is that there is very little physics left to be discovered

on a tabletop.

The way physics works is, the way discoveries in physics, by and large, work is you need

to go someplace you've never been before, either in scale...large, small, energy especially,

speed...once you've explored these extremes, you're at the hairy, bleeding edge between

what is known and unknown in the universe.

So, if you want to discover something you've never done before, build an accelerator that

hits an energy level that's never been hit before.

And the early universe is our best particle accelerator we know, so now we have the very

large tabletop version of the early universe, large and expensive, and it allows us to test

our ideas about what was going on.

And so, yes.

It's regime of the early universe that we have theoretical understanding of but we have

yet to have experimental verification for it.

I have visited the Large Hadron Collider twice; and on both occasions, I was more or less

literally reduced to tears.

I was moved so much by this stupendous effort of human ingenuity, human cooperation, multinational;

and I attempted to express my poetic fascination and interest in this terrific enterprise in

my latest book.

There was an unfortunate misprint.

It came out as the large Hardon collider.

Just the D and the R, right?

I spotted the misprint, and of course, I left it in; but alas, the publisher's proofreader

also spotted it.

She removed it.

I begged her on my knees to leave it in.

She said it was more than her job was worth.

Just a quick social comment.

The 1990's cancelled superconducting supercollider that was to be built in Texas had peak energies

three times as large as the Large Hadron Collider in Switzerland.

Congress voted to not continue its funding.

The project was scrapped, and now, the center of mass of particle physics is no longer in

the United States.

It's in Europe.

Now interesting to the scientists, while we'd rather it be here in America, we really celebrate

the fact that science continues to advance, and it's just a matter of whose nation's priorities

values it; and I saw that as the beginning of the end of America's leadership in this

realm.

Sure.

All right.

Thank you so much.

I probably have a question which is rather mundane in this setting, but one doesn't get

these opportunities very often.

I wanted to see what you thought about this.

Life that's been discovered at the point of sea floor spreading on earth is, I assume,

because I haven't heard otherwise also DNA based, as is everything else we know of.

My curiosity is whether there is a hypothesis or an explanation that has been, in fact,

devised as to how DNA can have this effect with the distance of 5,000 or 6,000 miles

in the ocean itself between that point and the surface.

Not miles in the ocean.

I mean, the diameter of the earth is only...you mean feet down?

I'm sorry.

Five or six miles.

Yes, thank you.

Exclude the thousand.

Okay.

I can give an astrophysicist's view, but I'd welcome the biologist.

I didn't actually hear the question, so you start off by...

Sure.

So, these extremophiles...these are creatures that thrive under conditions that would kill

the rest of us instantly, under high pressure, high temperature.

In fact, at the ocean vents, they're thriving at 300 degrees Fahrenheit.

The pressure of the water is high enough to prevent boiling, but the temperature is high

enough that it would cook anything else.

One of the great advances in exobiology was the discovery that life on earth is hardier

than anyone had ever previously given it credit.

We no longer need the room-temperature pond water to have life thrive.

The more we've looked in the earth, the more we have found life doing the backstroke under

extraordinarily hostile conditions, hostile to humans that is.

What that has done for us, astrophysically, is allow us to cast for life with a much wider

net than we had previously thought we had available to us.

Whereas before we would look in the habitable zone, the Goldilocks zone; not too close to

a host star, you water would evaporate; not too far away, water freezes.

You're looking for that liquid water zone made liquid by sunlight.

We find out all we really need is an energy source.

It doesn't have to be the sun.

Jupiter keeps Europa warm, one of its moons.

It has a liquid ocean.

It's been liquid for billions of years.

You want to look for life armed with this diversity of life, the hardiness of life,

even we find here on earth.

It has only broadened our search for life in the cosmos.

Among the many theories of the origin of life, recently people have started thinking about

life might possibly have started under what we now think of as extreme conditions of high

temperature, and it could be that we are now in the cold zone, which was not the way it

was when it first started, and that's an interesting possibility.

So, they would look at us like we're the extremophiles.

Exactly.

They look at us as though we're the extremophiles.

MS: My department chairman said that he wants you to go and ask your question.

I'm not going to tell him no, so please ask your question.

Keep it brief, and this is the last one before we go onto the book signing.

Thank you, Howard, for making this free.

Anyway, I read a book Consolation of Philosophy.

The main guy, Boethius, is condemned to death.

He has everything taken from him.

All he has is his reason and his sense of self, not even that; but he attempts to console

himself to this execution by reasoning that the world has order, that there is something

that keeps things together.

He uses his reason to try and get to the root of why he should be at peace with death.

The problem is his source of origin is a belief in God.

What would you do?

Well, I don't know if I fully understand the question.

I do know that, if he's about to be executed...

How about you are about to be executed?

Oh, I'm about to be executed.

You have nothing except your knowledge, your knowledge of science, your experience.

I would request that my body in death be buried, not cremated so that the energy content contained

within it gets returned to the earth, so that flora and fauna can dine upon it just as I've

dined upon flora and fauna throughout my life.

What about you, Professor Dawkins?

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DAWKINS TYSON

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The Description of The Poetry of Science: Richard Dawkins and Neil deGrasse Tyson