Practice English Speaking&Listening with: 2020 Isaac Asimov Memorial Debate: Alien Life

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>>NEIL DEGRASSE TYSON: Welcome, one and all.

I am Neil deGrasse Tyson, your personal astrophysicist.

Youif you are seeing me now, you are live streaming ouris it 19th or 20thannual

Isaac Asimov Panel Debate from the American Museum of Natural History.

And this was started backwhen Isaac Asimov died, we wanted some way to remember him.

He was local to the upper west side of New York.

In fact, many of his more than 600 books were written based on research he conducted at

our institutional library.

And so, his family got together, they joined us to figure out a way to remember him.

And he had covered so many topics in his novels as well as his books of nonfiction, that we

felt that a good way to remember him is to keep a living memorial in his name, the Isaac

Asimov Panel Debate.

And every year, we take some new topic thats hot and interesting and unsettled, primarily,

and this years topic is the search for alien life on earth and in the universe.

By the way, this year, we are celebratingis it thecelebrating the birthday of Charles

Hayden himself.

Is it the 100th anniversary?

You know, I should have looked that up, and I didnt.

Im sorry about that.

But anyway, were celebrating him, Charles Hayden, who first put out the money to bring

the universe to New York City and create what famously became the Hayden Planetarium, where

I now serve as director.

I had actually attended there as a kid.

Thats my first night sky.

You grow up in the city, you dont know anything about a night sky until you go into

a place where theres an expert, and they can point it out to you on a dome because

the buildings are tall, the lights are bright, pollution was rampant at the time.

And so, planetariums have a way of influencing us all, I think, especially me when I was

a kid.

But lets get straight to this.

The format of this evening is I have five panelists, each a world expert and why we

have them on this panel.

And youre going to eavesdrop on us.

This is not a formal debate, point/counterpoint.

Thats not how we do this.

Therell be topics thatll be put on the table, and each of us will explore them coming

from the point of view of our own expertise, at their own expertise.

And you get to hear scientists thinking out loud.

And its as though youre eavesdropping on a conversation were having at a conference

lounge, between talks or at the end of the day.

And so, thats the spirit and the soul of what it is we are bringing to you.

So let me first introduce the entire panel, just so you can get a look at them.

All right?

Nathalie Cabrol, from the NASA Astrobiology Institute.

Nathalie, welcome to the American Museum of Natural History virtually, and thanks for

being on this panel.

>>NATHALIE CABROL: Thank you very much for having me, Neil.

>>TYSON: Yeah, and well come right back to you in a sec.

I just want to get everybody up there.

Next, I have Vera Kolb of the University of Wisconsin, andin the chemistry department.

Vera, welcome.

>>VERA KOLB: Thank you very much for having me.

>>TYSON: Excellent.

And who else do we have?

We have Carol Cleland.

Did I say that right, Carol?


>>TYSON: Yes, excellent.

And youre at the University of Colorado.

A lot of snow there right now, I think, a little premature snow.

And youre the Department of Philosophy there.

All right?

No conversation is complete until a philosopher says so.


>>TYSON: Sooh, you agree with that.

Good to see.

>>CLELAND: [Indiscernible].

>>TYSON: Next we have Seth Shostak, an old friend, Seth, from The SETI Institute.

There you go, Seth.


>>SETH SHOSTAK: Well, its great to be here where, you know, the people are still smiling.

>>TYSON: The people are still smiling.

Yes, yes, because we, you know, the whole world is notcant always be about COVID

at every moment.

>>SHOSTAK: Well, California is burning.

Thats why I say this.

>>TYSON: Yeah, Californias burning as well.


So these are all signs of some apocalypse.

Im not quite sure which.

And last on this panel, we have Max Tegmark.

Max, from MIT Department of Physics, a long-time friend and colleague.

Welcome back to you, Max.

This is your third time on an Asimov Panel, I think.

Is that right?

>>MAX TEGMARK: Third times a charm.

>>TYSON: Third time.

And, Seth, this might be your second time?

Is that right?

>>SHOSTAK: Yep, thats correct.


>>TYSON: Excellent.


So its great to have all of you.

So lets go back, and I just want to hear if each of you in, take 30 seconds or so,

just to introduce yourself and what your expertise is that youre bringing to the table.

Nathalie, lets start out with you.

>>CABROL: Yeah.

I am the Chief Scientist at The SETI Institute.

I have a background in planetary geology and astrobiology.

And I explore extreme environments, and Ive been doing some work on Mars as well, with


>>TYSON: So you have not been on Mars

>>CABROL: With Rovers.

>>TYSON: With Rovers, okay.


>>TYSON: Just, you know, I never know about you guys.

You know, what youwhere youve been.

You said I work on Mars.

No, you dont.

You work on Earth.

>>CABROL: I work on Earth, but being a part of Mars missions with Mars Explorers and Rovers,

Spirit, in particular.

>>TYSON: Excellent.

And you come to this as a geologist, or as an astronomer?

>>CABROL: As an astrobiologist with a background in planetary geology.

>>TYSON: In planetary geology, okay.


And lets go to Vera.

Vera, tell us about yourself.

>>KOLB: Im a Professor of Chemistry at University of Wisconsin-Parkside, and my expertise

is in astrobiology.

I got my training in astrobiology from Stanley Miller and Leslie Orgel.

I would like to take the opportunity toto say to the audience there is a nice book that

everybody, I think, will love.

Its called Astrobiology for a General Reader: A Question and Answer Approach, which I wrote

with a coauthor, Benton Clark, who is also my fiancé.

And for those people who want to go into depth, I spent two years of my life to edit Handbook

of Astrobiology, came out in 2019.

>>TYSON: Wait, Vera, arent handbooks supposed to be little?


>>KOLB: Well, you see, I started

>>TYSON: Its supposed to fit in your hand.

Youre lugging the thing up with your hands


>>TYSON: So just, you know, and youre stillyou still have your fiancé after you finished

the book, so thats a good sign.

>>KOLB: No.

Actually, he proposed after we finished the book, which was very nice.

>>TYSON: Okay.


>>TYSON: Its still a good sign, still a good sign.

Carol, tell us about yourself.

>>CLELAND: Im Carol Cleland.

Im a professor of philosophy at the University of Colorado Boulder and the Director of the

Center for the Study of Origins.

My area is philosophy of science.

Im especially interested in philosophy of the natural sciences, especially historical

science, the geosciences, reconstructing the past.

And Ive been a member of the NASA Astrobiology Institute, both a coinvestigator on several

scientific teams, and also a cokey collaborator on several scientific teams.

And Ive written a book on the quest for the universal theory of life and edited a

collection of essays on the nature of life from a philosophic-borne scientific perspective.

>>TYSON: Excellent.

Well, thank youthank you for that.

And just for those who dont know, the NASA Astrobiology Institute is a virtual institute.

You can be a participant in that.

Theres grant money to support your research, and you would still behavekeep your

native affiliation, wherever that is.

But you collectively participate in this sort of unified search for life in the universe.

Seth, also of The SETI Institute, just like Nathalie.

So welcome back.

So tell us briefly about yourself.

>>SHOSTAK: Well, its not interesting, but Ill tell you anyhow.

ImI am the senior astronomer at The SETI Institute, which I think is a reference,

mostly, to my age.

The project that Im most interested in is SETI, which is a search for extraterrestrial


In other words, looking for life out there thats at least as clever as your next door


And we do that by, well, just what Jodi Foster did in the movie Contact.

We try and eavesdrop on radio signals.

There are other strategies that were looking at as well.

And although Ive written a couple of books, nobody every proposed to me when they were


>>TYSON: Okay.


>>TYSON: And you mentioned Jodi Foster in the film Contact.


>>TYSON: She used headphones to listen for aliens.

Is that what youre doing right now, during this session?

>>SHOSTAK: Well, I personally am not, but in fact, ourthesome of our experiments

are running, at least I hope theyre running, if they havent burned to the ground.

>>TYSON: Okay.

All right.

Max, tell us about yourself.

>>TEGMARK: So Im here at MIT.

Im a professor in the physics department.

Im also in the Center for Brains, Minds, and Machines, and also part of this brand

new center we have on artificial intelligence and fundamental interactions.

And I hope to bring two things to this panel.

One of them is during my work as a physicist, Ive spent a lot of time studying our cosmos

out there, and mapping it, and thinking about the physics of what limits we actually can

place onon life.

And the second thing I hope to bring is from my work in artificial intelligence, which

is what Ive been doing mainly at MIT for the last few years, which, I think, can tell

us a lot about technological life elsewhere in space, and even, perhaps, what kind of

space-faring life we humans might create.

>>TYSON: So itll be fun with you as part of this panel, because youre the only one

with no formal biology expertise at all.



>>TEGMARK: And I do have a claim to fame in that I married an alien, actually, which is

a little bit related to the time when I wrote my first bookan illegal alien.

>>TYSON: Oh, okay, I got you.

Undocumented alien, I think, they call them.

>>TEGMARK: Undocumented, yes.

>>TYSON: Soso, but good to hear sort of the base physics perspective on what is and

is not possible in the universe.

All right.

So letslets get to ourlets get to our topics.

Just so the public knows, I have a list of questions that Ill be bringing to the panel.

And theyve seen them all, but theyre not bound to them.

They can go wherever they want within them, and I have a steering wheel.

I just want to make sure I get through the topics, but theyll take us whereverwhatever

offramps the moments require.

So, Carol, let me justno, no, no.

Lets save that one forno, hold on.

Well come back to you, Carol.


>>TYSON: Nathalie.


>>TYSON: Yeah.


We cant lead with a philosopher.


>>CLELAND: Thats where you should lead.

>>TYSON: No, no.

Thatll confuse everything.

>>CABROL: Carol, dont worry.

Dont worry.


>>CLELAND: You should end with the philosopher.

>>CABROL: Ill segue to you.

Neil doesnt know what hes getting himself into.

>>TYSON: I dont know what Im getting into.

Thats maybe a good thing.

So, Nathalie, tell us, from yourfrom your side of the fence, what is life?

>>CABROL: Well, you know, the interesting response to that is that we dont have a

definition for life, at least not one definition for life.

We dont really know what life is, and basically, we are still trying to figure out.

I think that, you knowand the question I really like is that is there a need for

a definition for life?

As somebody who is doing, you know, experiment, I think that we can use some definition for

life for a specific purpose.

But if you are looking at what astrobiology does right now, its looking more at what

life does.

So, you know, the things we can measure, which is like metabolism, physics, and chemistry,

that leads to the metabolic activity of life.

But then, does that gives usdoes that give us any answer to why life is?

And then you go into the nature of life.

And so, either you are dealing with the piping of life, which I call the piping of life,

like astrobiology does, and then we become plumbers.

We are good plumbers.

We are worrying about the pipe, what the pipe is, the interaction of the pipe with the water.

But does that tell us anything about the nature and where the water is coming from?

And then today, if you are going to other extremes, there are new theories, and Im

taking one out of my hat here, but information technology or quantum physics are taking us

in places where science and philosophy are getting much closer together.

Theories like biocentrism are taking life way back at its most extreme quantum level,

where you say everything is energy and information, and information is only energy that is being

understood, when you can look at it and understand it.

And if this is really that, then astrobiology is only telling us about life as we can understand


But these new theories are telling you life is everywhere, and maybe the universe is alive.

And so, we dont define life, but then you just understand its manifestation and diversity.

And I think this is beautiful.

Its an incredible spectrum.

>>TYSON: So it sounded like once you brought in information and energy, I know Max will

have something to say about that in a few minutes, but does that mean there could be

life out there that would not satisfy that sort of base criterion?

I know what life is when I see it.

You know, thats the gut, you know.

Thats life.

That isnt.

Are you saying there might be some ways that life manifests that doesnt satisfy that

gut understanding of what life should be?

>>CABROL: Astrobiologists are still trying to figure out whether life is a transition,

or if its something that happens abruptly because something, you know, weird happened.

But these new theories are telling you life is everywhere.

There is no need to define life, because the universe is alive.

And basically, what we call life is only what we can recognize as life.

>>TYSON: Well, thats scary, because there might be life staring us in the face, and

we dont recognize it as life, that I dontI dont know how that encounter will end.


>>TYSON: I worry about that.

Vera, what is panspermia?

>>KOLB: Panspermia is an old idea, proposed by an old Greek philosopher, Anaxagoras, who

believed that universe is populated with seeds of life, and these seeds fell down upon earth

and started life.

So at that time, it was just an idea.

And about in 19th century it to startstarted to look like a hypothesis.

And at this time, it is definitely a hypothesis, because we have found out that spores of organisms

can survive in space.

This was done experimentally at the International Space Station.

And also, spores can travel through space inside the rocks which protect them from the

radiation, and that is called lithopanspermia, again, from Greek.

Panspermia means seeds everywhere.

Lithopanspermia means seeds inside the rocks.

And then, finally, this hypothesis was strengthened by the discovery that meteorites can travel

between planets, for example, Mars to Earth and vice versa, and between other planets.

So all of the sudden, what looked like an old Greek idea, now this idea became a hypothesis.

It seems to have enough support to be considered seriously scientifically.

>>TYSON: And we had a readymade word for it.

>>KOLB: Yes.



>>TYSON: Already in the catalog.

By the way, thatthat painting above your head looks a little [spermic].

Whats going on with that painting?

>>KOLB: Yes.

Well, Im glad you asked this.

This is my favorite painting by an artist Mark Dancey from Detroit.

You cannot see all of the details, but there are thousands of little specks of paint, which

look like stars.

And theres this red balloon traveling through space.

I saw it as a sperm traveling through space, trying to reach another planet in the universe.

Although, the artist named this painting The Apathy of the Stars, I call it Panspermia.


>>TYSON: Okay.

Well, all good art should allow you to interpret it in whatever way your feelings require.

>>KOLB: Yes.

>>TYSON: And if its not, then whatwhats it good for, right?

>>KOLB: Exactly.


>>TYSON: So, Carol, comingyou come from a whole other side of the fence here, and

youre trying to blow open peoples understanding of and their definitions of life.

Where are you trying towhere are you trying to send things?

What fights are you trying to create, really, is what Im getting at here?

>>CLELAND: Soso I think one of the biggest mistakes is the whole project of defining

life, the scientific project define life, because keep in mind that we only

>>TYSON: Sorry.

Toto define life or to find life.

>>CLELAND: The idea of defining life.

>>TYSON: Defining life.


There areI wont go intothere are these serious logical problems that philosophers

are well aware of with the whole idea of defining what are called natural kind turns, which

are basically categories that are carved out by nature and not human understanding.

But our problem with life is we only have a single example.

All life on earth is remarkably similar at the molecular level.

Were all descended from a comall known life on earth from a unique common ancestor.

And I love what Nathalie said about life as we understand it.

If you try to define life, youre dissecting your current concept of life.

Youre presupposing that all life in the universe is like our form of life, and we

just dont know that.

We certainly know there are certain conditions that are probably similar, but toand a

certain number of them are going to be similar between our kind of life and other life in

the universe, probably complexity and, you know, thermodynamic disequilibrium, extracting

energy from the environment in order to maintain order, and through an extended period of time

against the, shall I say, ravages

>>TYSON: Wait.

Just to be clear, when you speak of disequilibrium, if we were in total equilibrium with our environment,

we could not function, right?


>>TYSON: We have to be something really different to be what it is that we are, right?

>>CLELAND: And we know that life does that, but so do tornadoes and hurricanes, and they

last longer than mayflies.

So I think that its important to keep in mind that, yeah, we do have certain things

that are almost certainly universal for life, but a lot of the features that we think of

as common to life as we know it, even natural selection in the sense of standard Darwinian

evolution, what if you had a world which was, you knownatural selections really well

designed for a world that is not too stable and not too extreme in its changes, so that

organisms have a chance to adapt to the environment and to have the kinds of hereditary changes

that provide them with the resources for natural selection to operate.

But what if you had a world which was very slow and didnt have much in the way of

extreme environmental changes?

It wouldnt be particularly adaptive to have mutations, because youd already be

well adapted.

Mutations also cause organisms not to be so well adapted.

And so, II think that we have to be very careful trying to extrapolate some of the

things we think ofwhich are universal for known life on Earth, to alternative forms

of life in the universe.

Because its going to be very environmentally dependent, even though I think there are certain

featuresthere obviously are certain features that are universal to all life, and our form

of life exhibits those, but we dont know what they are.

>>TYSON: You make an interesting point.

I just never thought about it.

If you had a completely stable environment, it might be possible to adapt your way into

extinction, because theres nothing to adapt to, and all of these changes are happening

beyond your control.

>>CLELAND: Or you adapt so that you dont have much in the way of mutations.

That is to say maybe initially theres a period of time, and you becomeand the environments

very stable, and now its maladaptive to engage in too manytoo much in the way of


>>TYSON: So, okay, so you would mutate in such a way that you wouldnt mutate so much.

Thats what youre saying.


>>CLELAND: Well, I dont know how life starts, but if we assume it starts by, you know, were

getting gradually adapted to an environment, and then the environment becomes very stable,

then I think that the kind of natural selection and evolution that goes on on earth might

be maladaptive.

I mean, youd have toitswe are in the sweet point between changes happening

in the environment too fast, where extinctions occur, like the, you know, end-Cretaceous

extinctions when a meteorite hits, and we almost lost everything, and environments which

are very, very stable.

So evolutions very well adapted to our environment, but its not clear to me the

different environment.

>>TYSON: I like the idea that evolution adapted to us


>>TYSON: …instead of we adapting to evolution.

Seth, youreyou know, one of the letters in your acronym is an I, SETI.

And that stands for intelligence.

>>SHOSTAK: Right.

Thats why I dont have that letter.

>>TYSON: So let me pick up a baton from Carol, who she implicitly handed me, and Im going

to ask you, you have defined, presumably, ourselves as intelligent, and using that as

a measure of the intelligence of a species youre looking for.

Well, what is intelligence?

>>SHOSTAK: Yeah.

Well, IInot having anyhad any personal experience with it myself, I cant say too



>>SHOSTAK: Butbutfortunately, fortunately, when it comes to looking for extraterrestrial

intelligence, which is to say, you know, aliens, we dont have to worry too much about these

questions that Carol worries about, like what is life, right?

Because we dont have to find life.

We just have to find a signal that intelligence made.

Now, you might say, well, thats a, you know, a distinction without a distinction,

but its not really so.

If you pick up a radio signal, and thatits coming from the sky, and it moves across the

sky as the Earth rotates, you know, and that signal is at one spot on the radio dial, the

way WNYC is, for example, at one spot on the radio dial, you can say, well, thats not

a quasar, pulsar, or any of those other kind of rs.

Its a signal made by a transmitter.

Now, whats behind the transmitter, yes, maybe its a little green guy, you know,

who looks sort of like us, and if he moved in next door, you might, you know, invite

him over to dinner eventually, but maybe its nothing like that at all.

I mean, in aits not a very sophisticated idea that Ive promoted occasionally that,

in fact, were only here to get the machines going.

You know, wewe dont have machines that are intelligent enough to take over Neils

job, for example, although they probably could take over mine.

But, you know, 50 years from now, that situation may change, and it may be that human intelligence,

as nifty as we think it is, may be a very short lived affair.

And if thats the case, then most of the aliens are likely to be, or at least the ones

wed hear from, are likely to be machines.

And in that case, this whole discussion about what is life would be like trilobites sitting

around figuring out what the dinosaurs are going to look like.

Well, theyre going to be kind of a flat and bilateral, and theyre going to rove

around on the bottom of the ocean, and all of that would be wrong.


>>TYSON: Okay.

Did you just analogize us to trilobites?

>>SHOSTAK: The better of us, yes.


>>TYSON: Just so thatI just wanted to make a note of that.


>>TYSON: Max, youyou, like Carol, areyoure probably on the same side of the fence as

her from everybody else.

I want to ask you what is life?

And is artificially-created intelligence life, in your definition?

>>TEGMARK: I like to define life simply as a process that can retain its complexity and

make copies of itself.

And I like it so much that youll even find the definition onon my t-shirt here.

And the reason I like to give such a broad definition of life is because I really hate

the two anthropocentric definitions, which I view as as carbon chauvinism.

My sons, Phillip and Alexander, I looked at their textbooks from the Winchester Massachusetts

school system, and where they defined life as a laundry list ofof criteria, including

being made of cells and so on, which it seems so narrow that Im almost certain that ifif

Seth finds life in another solar system, its not going to meet, you know, that textbook


Then you asked about intelligence.

There, too, I like to think about it in the terms of a process of information, an information

processing process, which is simplyin thisin the case of intelligence, able to not necessarily

reproduce, but able to accomplish goals.

And the more complex the goals are, all right, the smarter it is.

So its very easy to imagine that we could design future robots and other AI systems

that also meet the definition of life, but we could also make things that are intelligent,

perhaps, without being alive or conscious, so that they could help us with things without

us having to feel guilty about switching them off.

In summary, I feel that the essence of both life and intelligence should be thought of

not in terms of what kind of atoms go into it, you know, but in terms of what its

actually doing from anan information process.

>>TYSON: So was this the foundation of your recent book, lifewas itIve lost track,

2.0 or 3.0?

>>TEGMARK: 3.0.

>>TYSON: Lifeso whats life 1.0?

>>TEGMARK: So life 1.0 is really dumb life, like bacteria, and no offense to trilobites.

Ititit wont learn anything during its lifetime and has its intelligence basically

hard coded in by its DNA.

And I call us here life 2.0, because unlike bacteria, we actually learn stuff during our

lifetime, right?

We can install a module in our brain that speaks a new language or knows a new job skill.

So we can install new software in our brains, basically, but we still cant upgrade our


Life 3.0 can replace not just its software, but also its hardware, and the sort of future

technological life that Seth thinks he might find wouldwould probably be life 3.0.

If it decides to be stronger or faster or whatever, it can upgrade its hardware.

>>CLELAND: So can I just respond to Max?

>>TYSON: Yeah, yeah, please.

Go ahead.

Jump right in.


So, Max, II agree with you that its probably a necessary condition for life that

it be a phenomenon or a system thatsthats complex and maintains itself in a sort of

out-of-equilibrium state.

But thats not a definition.

The problem is youve just given some general conditions, and again, we have tornadoes and

hurricanes, which last a remarkably long period of time, as we all know, that do the same


So to get actually at life, unless youre going to count all kinds of phenomenon as

living that we dont normally, youre going to have to add some other conditions.

And Ithatsthats what I dont think we have a good understanding of, which

is why I hate people who talk aboutI dont hate people.

I hate definitions of life.


I like them, but I dont


>>TYSON: I knew it.

I felt it.

I felt it.


>>CLELAND: Butbut I think the whole project of defining life locks you into this box,

because definitions give you necessary and sufficient conditions.

They tell you what life is, and anything that doesnt fit into the box is immediately

consigned to the nonliving category.

So I think the word definition is really problematic in

>>TYSON: Wait, wait, Carol, but theres anotherpossibly another way to imagine

this, that you can define something and, depending on the definition, it could embrace something

youd never imagine it could have embraced before.

For example, if youwe agreed in the biology books, metabolismwhoseit was youryour

sons book, Max?

>>TEGMARK: Right.

>>TYSON: Metabolism, cell, it would have to reproduce itself, you know.

Andand if you looked at stars, they reproduce themselves.

They have a metabolism.

Theyre born.

They live out their lives, and they die.

So theres definitions of life where stars are alive.

>>CLELAND: Yes, and the great Immanuel Kant, a very famous philosopher in the discovery

of theas an astronomer, I think he discovered the galaxies.

>>TYSON: Well, hehehethe nebular hypothesis was very popular and correct.

>>CLELAND: Yeah, the nebular hypothesis.

Heand he and other people, going back to Aristotle, did wonder whether stars were alive,

because an Aristotle definition of life, it turned out that the very fact that everything

on Earth stopsyou push it, and it stopsbut of course, we have in the heavens these bodies

that continue moving.

And so, the view was, he thought, that motion, motility was a defining feature of life, because

he thought that the natural state of motion was rest.

>>TYSON: Well, thats why we dont learn our life lessons from Aristotle.


>>CLELAND: But thats also a lesson

>>TYSON: Galileo came along.


>>CLELAND: We may be a bit like Aristotle in our current state of knowledge.

>>TYSON: Oh, I see.

Thats the analogy.


Thats the [indiscernible].

>>TYSON: So let me ask you, and Im justNathalie, Im just trying to understand something.

You look for alien lifeI call it alien lifeexotic life on Earth, because there

are places that have been sort of biologically distinct, separated for immense periods of

time, right?

So youreyoure intrigued by places on Earth that has truly exotic life.

But if weif we agree that all life on Earth has common DNA and a common single-celled

ancestor, how alien is the life that youre finding on earth?

Its just less familiar to you.

Why is that a useful model for anything you might look for anywhere else thats not


>>CABROL: I think thats a fair question, except that I wouldnt call this alien.

I wouldnt say its isolated.

Nothing on Earth is isolated.

We live in a system, and this is maybe something that people have a hard time, you know, figuring

out, especially right now, that everything you put in that system is going to come back

at you and bite you some time.

But lets say that where we go, we go to places that are what we call extreme environments.

And they are producing very good analog environment, which means that they are similar to something.

And those something are like the very beginning of Earth history, very different conditions,

where you had lots of ultraviolet radiation coming at the surface, because there was no

ozone layer.

But these condition are also very similar to what Mars was at the time.

And I wont go back to those, you know, definition of what habitability is and all

of these things, but imagine that you have conditions that are very similar from one

planet to the other, very early on, and the stuff that makes us, like carbon, like oxygen,

hydrogen, and nitrogen, etc., its also very common.

And we also have found organic molecule on Mars.

We know that they are there.

Organic molecules are not life.

They are the bricks of life, just like Legos.

They are only


>>CABROL: …Legos when they are put on the table, and then you can put them together,

and they may become more or less complex, right?

>>TYSON: Weve got to complete the analogy.

So early life would have been Duplos, but later complex life would be Legos, right?

Thats how it


>>CABROL: Exactly.

No, but the point is that when we go to those places, we can look straight in the eyes,

and I dont know if bacteria have eyes, but we can look at these very, very ancient

and primitive organism that are telling us something very profound about what life was

early on.

And in conditions that are very relevant to what, say, Mars or any other planet, for that

matter, we can now extend to [indiscernible] planet, because we have this gallery of new

planet, try to figure out what life would respond to extreme environment that are analogous

to different planets elsewhere.

>>TYSON: Okay.

I had not fully appreciated that important dimension of that work.

I kept thinking of it as its an exotic life form, and you dont find it anywhere

else in the world, so you study it.

But if that environment matches some other environment we know thats not on Earth,

youclearly, you will learn things from it.

But let me ask, so Vera, if we go to Mars, and we do find life, of the kind Nathalie

is imagining, or that you might even be imagining, might it have DNA?

Is there anything that weve suspiccouldcould DNA be universal in the same way geologists

expect the rocks to be similar?

Iron oxidizes on Mars just the way iron oxidizes here on Earth.

Could there be someand Ill bet Carol has something to say about this, too, about

a universal understanding of life.

But could DNA, as complex as it is to us to think about, could it be a universal thing

that biology does?

>>KOLB: Well, let me answer first this way.

The first question is is life on Mars, if we find it, or its remnants, the same as life

onon Earth in terms of DNA?

Because you were specifically for

>>TYSON: I think she froze.

>>TEGMARK: Its that Martian environment.

>>TYSON: Yeah.

No, the Martianthe Martianoh, wait.

So, Vera, youre back.

Could you give us that sentencecould you give us that sentence one more time, because

you froze up onright in the middle.

We think martinis did it, but okay.

>>KOLB: So to answer your question directly, if we find life on Mars or its remnants, is

DNA going to be the same as DNA on Earth?

This is theyour question the way I understood it.

And my answer is the following.

There are two possibilitiesor, well, two main possibilities.

Either we will find the same type of DNA as we have on Earth, which could indicate panspermia

from Mars to Earth, because there isthere is currently an understanding that life could

have started on Mars first, and then it was transferred to Earth via panspermia.

Or it could be different.

However, in my opinion, DNA or its functional equivalent, the emphasis is on factual equivalent,

must exist as part of any life.

Now, let me support this somewhat.

When you think about DNA or RNA, which are onon Earth right now, there are literally

millions and millions of years of evolution where this was perfected.

DNA was perfected for its function.

And when chemists tried to make DNA lookalikes, thinking maybe DNA lookalikes could be important

for extraterrestrial life, they did two specific things.

They tried to change the backbone of DNA from phosphates to sulfones, and they found out

the whole thing collapsed.

It couldnt make a helix.

It just coagulated and collapsed, which means there were some requirements for this backbone

had to be repeated to charge.

Another thing chemists did, they said

>>TYSON: So when you said it have to be, maybe theyre just not clever enough.

Whywhy do you say it has to be

>>KOLB: Well, I was going to comment on this in a second, in another attempt, and then

Ill comment on this if theyre clever enough.

So another attempt was why do we have to have ribose?

We could have other sugars.

And Eschenmoser, a very talented chemist, basically, synthesized all different sugar

analogs of DNA and found outby the way, the previous work was done by [Bener] with

sulfonesand found out it functions, but not so well.

Now, talking about not being smart, with all due respect to my fellow chemists, and Im

one of them, we, I think, are very smart, but you cannot do in lifetime of a chemist

what evolution did in billions of years.

So chemist against the evolution, chemist lose.

>>TYSON: Okay.


>>TYSON: Carol, thethis problem of a sample of one, it plagues all branches of science,

and youreyoure a philosopher of science broadly, as well as your specific interests.

So how do you as a philosopher think about thethethe singularityno, I cant

use that word.

No singularities.

>>CLELAND: Please, dont.

>>TYSON: Maxll get on my case.

How do you think about this, the problem of aof a singular genesis for anything?

>>CLELAND: So I thinkso I think in general, its a problem.

But were in better shape with regard to other areas of science, because we have more

than one example.

We have no evidence, for example, that water on earth is distinctively a single example,

like we have evidence that life on earth comes from a single example.

And theand the evidence for that is just what Vera talked about.

I mean, its actually narrower than that.

Its nucleic acids, where we know that there are alternative bases that could have our

created nucleic acids that would be perfectly functional in the right organismal environments,

except they arent used by our form of life.

Same with proteins.

So we have reason to believe, unlike we do for other phenomena, that we really do have

a single example.

And the column were using from the single example, logically, is just very profound.

I mean, if you were an alien, and you came down, and you were interested in coming up

with a theory of mammals, and you had only zebras to look at, what would you emphasize?

What would you think would be the general features of mammals?

It wouldnt

>>TEGMARK: All mammals have stripes, of course.

>>CLELAND: Yeah, exactly.

It wouldnt be their mammary glands.

Only 50% are going to have them.


>>CLELAND: So its only

>>TYSON: And theyre tasty to lions.


This would be the total conclusion.


>>CLELAND: And theyre tasty to lions.

Butbut its really important, I think, to see that biology is in a position that

other fields, like chemistry and physics, arent, because we have good reason to believe

that the central category, life as we know it, is descended from a single example, and

we dont know what the alternative possibilities are.

Maybe Veras right.

Maybe always life uses nucleic acids.

But its not clear to me that environments very different than earth, such as Titan,

[Derk Sherks Mikak], just for example, argued that, you know, most of our laboratory work

on silicon as a non-carbon based form of life talks about how it doesntits not

a veryit doesnt make very good polymers that have the kind of characteristics that,

say, DNA, especially, and proteins have.

That under environments on Titan, for example, he argues, theres some reason to believe

low oxygen, very low temperatures, no liquid water, it can form much more complex polymers

that would have the capacity to, perhaps, provide us with an informational molecule.

II just dont think we know what the

>>TYSON: Soso Veras point was that if its not DNA, its got to be something

thatthat codes information.


Thatthat Ill agree.

>>TYSON: Andandand, Max, if were trying to code information, does it even have

to be molecular?

I mean, thatsthats another kind of bias.

Thats athats athats a molecular bias, if you will.

>>TEGMARK: Yeah.

Let meI mean, let me give two answers to that.

If we are trying to code information in a way that evolution can evolve from scratch,

then its going to havebe very limited, thethe range of solutions we canit has

to be made out of a molecule that are abundant in the biological environment.

It has to be an organism that can self-assemble, and then we getand so on.

Whereas if we get to design it with our intelligence, now you dont need any of that.

There are so many more possibilities, right?

And II think, for that reason

>>TYSON: Well, toto Veras point, we do invoke our intelligence, and its human

beings working over several months or years, and were not getting it, but nature had

a billion years to get it right.

Soso what do you mean, lets use our intelligence, and we canwe can figure it


>>TEGMARK: What I mean is, if youif you zoom out and look at this in a more cosmic

perspective, then I think in our universe, life will probably end up being like a one-two


First it takes a really long time forfor life at our level to evolve.

Weve been sitting aroundEarth has been sitour universe has been sitting around

for 17.8 billion years until, you know, the Asimov lecture series was launched, right?


>>TYSON: 13.8 billion.

>>TEGMARK: And then in very short order, we went fromfrom inventing fire to inventing

smart phones to flying into space and so on.

And we now realize from the laws of physics that its actually pretty easy to build

technology that spreads life to other solar systems, and ultimately, even otherother


It can happen way faster than the 13.8 billion years weve been waiting so far.

So I think when we look for advanced life elsewhere in our universe, I agree with Seth,

that itll be very unlikely that the first life we find is still stuck in stage one,

its biological stage.

Its much more likely that well see something which has transitioned to a designed, technological


And in that case, theyre not going to be using information storage and DNA.

Theyre going to be using something much more efficient that they invented.

>>CLELAND: Soso can I just say something here?

I agree with Seth, but not necessarily with you, Max.

>>TEGMARK: All right.

>>CLELAND: And this is the sense in which I agree with Seth.

I think that when youre talking about intelligence, that robotic forms of intelligence are likely

to beexist in, you know, maybe wandering the galaxies.

I dont know.

But I think that calling it life information, purely informational, nonphysical or nonchemical

phenomena like this, calling it life, thats a different issue.

For example, you can imagine a simulation of water and a computer, a very complete,

very accurate simulation of water, but do you really want to call it water?

Are the chemists going to be very interested in it?

So I think life is more like water than it is like intelligence.

And thats, by the way, its philosophically

>>TYSON: [Indiscernible] Ive got to pause for a second on that.


>>TYSON: Life is like water, but its like


>>CLELAND: Its wet.

>>TYSON: Let me get back to that in a second.

Nathalie, Carol mentioned Titan several times here, Titan, a moon of Saturn with a very

thick atmosphere, and you study exotic environments.

Is that environment too exotic for you to imagine life to thrive in, given its a

very cold temperature?

>>CABROL: [Indiscernible], and Titan is really about a different chemistry from what we know.

But, you know, its always the same debate.

We have to start somewhere, so we start with the environment we know.

If we take what we know, and we just export it to Titan, then we have a problem.

But it might be that Titan came up with something completely different.

And again, this is not my area of expertise.

I am not a chemist.

But what we see in the atmosphere of Titan is the formation of organic molecules, and

itsthey are raining down.

They are raining down on an environment that is very exotic to us, like ethane and methane


We also know that there is a water [indiscernible] ocean underneath, under the surface of Titan.

So whatwhat if those molecules are actually penetrating in the subsurface and reach that


We dont know.

We really dont know, but it

>>TYSON: But youre still trying to eek life as we know it out of an environment that

could be making life as we [indiscernible].

>>CABROL: Because its the only thing I can do at this point in time.

As Ive said, I am not a chemist.

I am not a [mother] and a chemist.

Somebody like Vera, who is doing physics and chemistry, might be able to take those molecules

that we know and project them into an environment that is exotic.

And this is basically what we are trying to do right now when we are going to those extreme

environment and trying to understand how life can adapt, how far it can adapt, how can we

stretch it?

And obviously, this is life as we know it.

But can it adapt to some of this environment we see in the outer solar system?

For instance, is life possible on Pluto, right?

Like three years ago, four years ago, I would have waved my arm and say, you know, you are


But see whats happening.

Sharon and Pluto, they are pulling on each other.

There is energy.

There is shelter.

There is etc., etc.

>>TYSON: Sharon and Pluto, Plutos moon, Sharon.

>>CABROL: Yeah.



Andand so, you see those worlds that are we learning about with Kepler and with TESS

and soon with [indiscernible].

We have to start somewhere.

I think that its absolutely right to understand our constraint, but its also fair to say

that we have to start with something we know and move from there.

And I think we are doing pretty good with that.

We are starting to stretch, you know, our gallery or our zoo of potential habitable

environment, and by no mean in my mind I am constrained or limited to search for life

as we know it.

But I am certainly more familiar understanding the constraint of such life and trying to

expand them somewhere else.

Thats all I

>>TYSON: Let me ask you, Seth, is there an analog to this problem in the SETI world?

Because youre assuming theyre using radio signals, you know.

Theres been a lot of assumptions going on here.

Is there someone stepping out of it and saying maybe theyll try to communicate in a whole

other way?

Lets be more inventive than that?

>>SHOSTAK: Yeah.

Well, certainly, a lot of my correspondence speaks to that.

By the way, III


>>SHOSTAK: …do feel that I should point out that the namesake for this debate, Isaac

Asimov, actually wrote a paper on alternative chemistries for life.

And so, he investigated, you know, whether, for example, silicon-based life, which is

the choice of nine out of 10 Hollywood screenwriters, you know, under what conditions would that

be possible.

Anyhow, not toto take things away.


>>TYSON: But just to clarify, because Iifif people dont remember their chemistry, silicon

pops into the creativity of screenwriters and storytellers because it sits directly

below carbon on the periodic table of elements.

And as you might remember, all of the elements in a column make similar families of molecules

to each other.

So thethe notion that you just swap in aa silicon atom with a carbon atom and

then replicate life, silicon-based life.

So I just want to make sure everybodys on the same page.

>>SHOSTAK: Yeah, and underneathunderneath the silicon, I believe, is germanium, and

underneath that is tin.

And we do have an example of tin-based life in The Wizard of Oz.

>>TYSON: Okay.


>>CABROL: The only thing that is funny with silicon life is that they are actually coughing


>>SHOSTAK: Yes, they are coughing sand.

>>TYSON: Im sorry.

Theythey are what?

>>CABROL: They are coughing sand.

>>SHOSTAK: Coughing sand.

Well, they should get tested.

Thats all Im going to say.


>>SHOSTAK: But [indiscernible]…Im sorry.

>>TYSON: Go on.

>>SHOSTAK: No, no, no, your question, you better repeat it, because its been so long


>>TYSON: Oh, yeah.

No, no, no.

I would sayI was headed somewhere else.

I just wanted to getto hear from you how inventive people could be.


>>TYSON: Because youreyoureyoure still listening for radio waves.


>>SHOSTAK: Yeah.


Well, well, yes.

Youre right, andandand there are plenty of people who will say, well, you know,

radio, thats so old school.

But of course, its not really old school.

Radio is a technology.

Television is a radio, right?

I mean, the Internet is, your Wi-Fi, its radio.

Its all the same, from the same [indiscernible].

>>TYSON: Seth, you sound like an old man on the porch in a rocking chair, saying its

all the same.

These younguns, what are they doing?

>>SHOSTAK: Well, well, thats right.

I find myself doing that more and more often.


>>SHOSTAK: But one tries to think out of the, you know, the quadrilateral, whatever, because

in fact, were already looking for, for example, flashing lasers in space.

There are several experiments at the University of California Berkeley and SETI Institute

to try and find communication that way, and you get more bits per second, you know, with

that kind of communication.

So maybe the aliens are doing it.

But I would suggest to you that an alternative approach, which Ive become enamored of

recently, is to look for the most advanced societies, because those, if they are societies,

at least the most advanced intelligence, because theyre likely to have done the most to

make their presence obvious or not obvious, perhaps.

And that is to look for artifacts, right?

If you have a really advanced society, maybe theyve just built a giant, whats called

a Dyson sphere, ayou know, a big fleet of solar panels orbiting in their solar system

to collect all of the energy they need.

Or maybe theyve built something else, big, something obvious, something that isnt


Maybe theyve rearranged star systems.

Maybe theyre even trying to change

>>TYSON: Are you looking for this?

Theres a lot of maybes.

I dont hear you saying that youre looking for it.

>>SHOSTAK: Well, I, you know, are you old enough to hear this story?


Letlet me say that we havent actually


>>SHOSTAK: …thats really hard to do, actually.

Looking for artifacts is a great scheme.

Thats the way they found life in the 19th century, or intelligence.

They looked at Mars, and they saw, you know, crisscross-y lines, which they assumed were


So itit has a long history, but it doesntand its not prescriptive.

It never tells you this is what you should look for, and thats the problem with it.

But all astronomers should pay attention.

>>TYSON: Vera, whatwhatwhat pre-life chemistry is required to get life as we know

it, or maybe as we dont know it?

Because all life, all biology is chemistry manifested at some complex level.

So have youhow much attention is given to what the pre-life conditions need to be?

>>KOLB: Preprebiotic chemistry, which is chemistry which occurred before life and occurred

naturally without any outside investigators, obviously, intervening, this type of prebiotic

chemistry has been now part of laboratory experience, and we have made tremendous progress.

What was done before, for example, nucleotides and nucleosides, which were very difficult

to be prepared directly from nucleobases and sugars, now chemists, notably Sutherland and

Powner, found creative ways to make these prebiotic chemicals.

And so, to answer your question, I do not believe that prebiotic chemistry right now

is a big problem for our understanding of life.

What is the big problem is how the abiotic to biotic transition occurred.

So you can think about the abiotic chemicals.

Lets say they were all made on early Earth or early Mars or other planets.

They were made by this chemical path, was depending which type of chemicals they had,

but these chemicals were pretty similar.

So now, we have a heap of chemicals, okay, a heap.

That is not life.

This heap to become a life has to become a system.

Now, what is a system, and how does system differ from a heap?

In the system, the parts interact among themselves in a complex manner.

So life as we know it has three subsystems, metabolism, information system, and aa

membrane system.

And it is a part of a larger system, which is environment and biosphere.

So this is the big system of life.

And then we have abiotic heap, if I may say that, and we do not know how the transition


So this is the biggest knowledge gap in the theory of life, and we believe that we can

possibly solve this thereyou know, through some more experiments.

There are experiments along the lines of synthetic life, Craig Venter and others.

There are also a few

>>TYSON: Just to be clear, synthetic life is people creating life in the laboratory.

>>KOLB: Well, we havent done that yet completely, but you know, you can sort of take a cell,

get its DNA out, and put artificially-made DNA into a cell and cell functions.


So we have not made life from scratch, but I would not be surprised, looking at the tremendous

progress, think about the fact that DNA was discovered in 1954, okay?

And what we have now is tremendous progress.

So I think if we make any sort of synthetic life, it may not be the same replica as our

life, which is a historical process.

>>TYSON: But, Vera, didnt we all see that movie, where theywe made synthetic life?

And it didnt end very well.


>>KOLB: You know, I stay away from any science fiction movie, because science is much more

mysterious to me than science fiction movies.

>>TYSON: So they asked Ray Bradbury why do you write such dystopic future science-fi


Is this what you think the world will be?

And he says, no, no, no, no.

I write them so that youll know to avoid them.


>>KOLB: Well, and you know, okay.

I thinkanyway, whatwhat I am saying to you is that, in terms of your question,

the starting materials are not so important as this transition.

And also, the most important thing is we will make functional equivalence of proteins, of


And there is no algorithm by which we can make an enzyme.

For example, Stuart Kauffman had this great think.

He says you cannot have an algorithm for screwdriver, what screwdriver can do.

You can describe two or three functions, but there are myriad more functions that screwdriver

can do.

So for us to lock our thinking into chemicals which could produce exact enzymes as we have,

I think its counterproductive.

It could be anything with the same function.

So we are looking for functional equivalence rather than exact replica of what we have.

>>TYSON: Could it be that you need an enzyme to make an enzyme?



>>KOLB: No.

Actually, this is a very good question.

And goingwell, going back to the screwdriver, the primitive enzymes, and this is really

fascinating, the primitive enzymes wherethey could do anything.

Its like your screwdriver.

If you look at what people have who are not mechanically oriented in their toolbox, they

have pliers, a screwdriver, and a hammer.


You can do lots of things with these primitive enzymes.

And theyre kept through the evolution why?

If everything goes wrong, you can always fall back on these old enzymes, which can do anything.


>>TYSON: I think a little bit of glue might help, too.

>>KOLB: Yes.

>>TYSON: Carol, letlet me ask you, the word biosphere was mentioned here, and in

researching your own professional publications, I came across a shadow biosphere?


>>TYSON: Could you tell me what that is?

>>CLELAND: Yeah.

So I coined the term shadow biosphere about 2003, and a paper came out with Shelley Copley

on the topic about 2005.

And the basic idea behind a shadow biosphere is the idea that there may have been more

than one origin of life on Earth.

Its completely compatible with the little that we do know about the origin of life on

Earth, and that, you know, we know that there areand I think Vera mentioned thisthere

are alternative suites, and Steve Brenners done a lot of this workalternative suites

of amino acids that could make proteins that were perfectly functional in the right organismal


Similarly, there are nucleobases, different sugars that could makethis is, you know,

nucleic acids, which are different than our nucleic acids that would be perfectly functionable

in the right organismal environment.

They dont exist.

All life on Earth is just select a small suite of all of the amino acids and nucleobases

that are available in nature, abiotically, delivered, in some case, by a meteorite, produced

in hydrothermal activities and other cases.

So our core of life has just used a small suite of these.

And whereifyou know, if life originated in Earth, and Vera brings up panspermia.

And certainly, thats a possibility, that life itself or some of the basic building

blocks of life, perhaps proteins or some oligonucleotides were delivered to earth by meteorites and

basically seeded Earth, in some sense.

But if life did originate in Earth, then it seems that all of the building blocks for

alternative forms of life were available at the time, we dont know when, that life

originated in Earth.

And so different, there would be different, shall way say, cradles of life with different


And I see no reason why they wouldnt have produced early forms of life, if life is a

natural phenomena, not a scientific miracle, but a natural phenomena that arises under

the right physical and chemical conditions.

>>TYSON: Right.

So where is it now?

I meansobecause if life arose so quickly, as evidence suggests, then why doesnt it

keep arising all around the world in whole other pocket, bio pockets?

Is that what youre referring to as a shadow biosphere?

>>CLELAND: It could be still arising, but the conditions were very different back, you

know, during the4 billion years ago.

What Im more interested in is whether or not there could be microbial forms of life.

We know that multicellular organisms are fairly rare.

They didntthey arose less than a billion years ago, and the Earth is 4.5, some 4.5

billion years.

So most of the history of life on Earth had been microbial.

And the question is could there be actually unrecognized microbes on Earth that are descended

from an alternative origin of life?

And it seemsand it turns out that the tools that microbiologists use to explore the microbial

world would not recognize it if it existed.

Those are microscopy, and I dont want to go ingo into more detail, but microscopy

and cultivation and metagenomic methods.

Metagenomic methods will onlythey require hybridization.

And hybridization requires similar, you know, nucleic acids, and nucleic acids that differed

even modestly, different code

>>TYSON: So it could beit could be sitting under our noses, and we would not

>>CLELAND: Literally.


And what we know about microbial communities is they contained a variety of low abundant

varieties of microbes, and along with abundant microbes.

Its not as if they would be necessarily out competed.

Microbes are quite friendly with each other, it turns out.


>>TYSON: What are biosignatures?

>>CABROL: Im sorry.

Go ahead.

Go ahead.

Oh, I just wanted to

>>TYSON: So, Vera, you made a comment on Carolsgo ahead.

>>CABROL: …comment on what Carol was saying is that from the astrobiology standpoint and

the exploration standpoint, the search for life beyond Earth, personally, I think that,

you know, engaging our self in trying to understand the shadow biosphere and how to figure out

if there is another type of life on Earth that we cannot recognize is one of the best

avenues and probably one ofthe one that will take us the most rapidly to find life

somewhere else, because this is typically, typically the kind ofof thing we need to


We need to actually push the boxes we arewe have put our self into.

The shadow biosphere is one example of the type of individual framework, I would say,

that we need to pursue, in the same way that I see theories like biocentrism today that

are blowing out of the water anything we think about life, you know, and what is life, and

the nature of life.

Im not saying they are true.

I dont have theyou know, the academic background to understand everything.

But I know for a fact as a scientist that by exploring those avenues, we are going to

understand what is right, what is wrong, and expand our horizon.

And so, this is what I am saying.

I can talk to you at length about biosignature.

I am going to talk to you about biosignature as we know it, you know, as we know them.

And back again we are here on Earth.

Biosignatures, they can be chemical.

They can be physical.

It can be a mound of stromatolite.

Do you know those little blue and green algaes that gave the first fossil on earth 3.4 billion

years ago in Australia?

People are actually still debating knowing whether its life or not.

There are now other studies that are telling us that we have direct or indirect traces

of life, and some of the indirect traces of life in those studies are right, they might

be 4.28 billion years old.

This, too, blew my mind away, because if thats the case, it just mean that life was there

as soon as the crust of our planet had cooled down.

So that tells maybe something else about what Vera is interested in, which is panspermia,

or the ability of life to be part of the planetary process.

So, you know, Ive been hearing a lot of things tonight up to this point.

But its all very much so into what we are used to, you know, into the individual framework

and the box we are used to.

Its a lot more exciting and more thought [provocating]…provocative to just push those,

you know, those walls and those boxes and collapse them.

And I think that, in many ways, what Carol was saying, what biocentrism is saying is

bringing those thoughts together, and it might be the best to take us to life beyond planet

Earth and thinking about life as we dont know it.

>>TYSON: Vera, is intelligence inevitable in an evolutionary arc?


We cant hear you.

Try again.

>>KOLB: Can you repeat the question, please?

>>TYSON: Yes, I can, and we do hear you.

Iswould you say intelligence is an inevitable onon the path of the evolution of life?

>>KOLB: Well, I

>>TYSON: And the growth of complexity, molecular complexity?

>>KOLB: Well, I would like to answer this question two different ways.

One is we really do not know what intelligence is.

So, if we

>>TYSON: Seth knows, by the way.

We understand.

>>KOLB: Well, yes, but


>>KOLB: …for example

>>TYSON: Its a machine sending signals.

Thats intelligence.

>>KOLB: If we try toif we try to define life, lets say, by using a laundry list

of characteristics of life, and one of these characteristics is intelligence, then bacteria

would not be alive, because we would have intelligence, but bacteria dont.

This is one issue that we have.

We always think that intelligence belongs to us, but the lower organisms dont have


Still, I would say that even the lowest organisms, acting to their own behalf, they know how

to survive, they know how to swim upstream, bacteria, to get some sugar, not to talk about

mammals, if you have a cat, lets say.

You look at in cats eyes, you know, you see devotion and emotion.

So, okay, so this is

>>TYSON: No.

I see that they dont really care about you at all.

Thats just what I see when I look into a cats eyes.


>>KOLB: They dont.

They dont.


And thats why we desperately try to make them love you.


>>TYSON: Or theyre putting on a good act ifif they do.


>>KOLB: Yes.

However, to answer your question more directly, you were saying is intelligence inevitable?

Philosophically speaking, there may be two different philosophies which claim progress

of matter, evolutionary progress of matter towards the highest level that we have now,

which is intelligence.

I personally do not believe that intelligence of a sort that we have is inevitable.

And instead of doing my own philosophy here, I would like to cite one of my favorite philosophers,

Nicholas Rescher, who wrote about intelligence and science of aliens.

And he had this example, out there somewhere, on some planet, there are moles who live underground.

They cannot see, and they never saw the light.

They do not understand the skies.

They would not understand hydrogen line or anything.

And since they live underground, they may communicate by the system that is not known

to us, maybe some sort of electromagnetic things, which looks crazy initially.

But we know now that some birds navigate through magnetic fields, and so on.

So I think there are different types of intelligence, and which type of intelligence will develop

depends on the circumstances of evolution.

>>TYSON: Okay, so the intelligence serves the organism in its environment is what youre


>>KOLB: That is correct.

And also

>>TYSON: So, Maxoh, so, go on.

>>KOLB: Im sorry.

I just want to add one thing from my childhood.

I know this may look like going back too much.


>>KOLB: Once I had the discussion with my father saying that how, you know, only we

are intelligent, and insects, for example, are not intelligent.

And he send me to the library to get a book by Maurice Maeterlinck, you know, about bees.

And after I read that book about bees, I said, aha.

I have to work on my own understanding, you know, that we are the only species which is


Bees just develop in a different direction than us.

>>TYSON: And bees communicate with each other in an abstract language that gives direction

as [indiscernible]…

>>KOLB: Yes, they do.

[Indiscernible] later, we found out recently, you know, they do dances.

They have very complicated way of communicating.

And so, and you know, so we have other societies, like ants and so on.

So let us not be so anthropocentric to say, oh, we are the only intelligent people on


>>TYSON: Sososo, Max, is it possible that there is a life form out there that is

so vastly greater than us in intelligence that it will not see us as intelligent at


Are we to them what worms are to us?

Andand the audacity of us to say lets look for intelligence in the universe.

On that scale, they would not even notice us at all.

>>TEGMARK: If theyre out there and can see us, II think they would notice us.

They might find us very arrogant towhen we start talking about ourselves as the pinnacle

of intelligence, asas some humans have done, right?

But I actually have aI have a minority view on this.

Im willing to bet with anyone else on this panel, with even odds, that we are the only

species in our entire observable universe thats gotten as far as inventing telescopes.

II can explain why that is in a little bit, but

>>TYSON: What?


>>TYSON: What?

>>TEGMARK: You know, and for the bet, good.

What are thewhats at stake?

>>TYSON: Meet me outside.


>>TYSON: Wait, just to be clear.

Just to be clear.

Seth, on my tie is an image of the Milky Way.

>>SHOSTAK: Yeah.

>>TYSON: Show me

>>SHOSTAK: Howhowd you get that picture?

>>TYSON: I got people.

JustjustI got people.


>>TYSON: So how much of the Milky Way have we searched forhas SETI looked for life?

>>SHOSTAK: Well, I mean, it depends on looked, your definition of looked.

Butthat sounds like President Clinton, I guess.

Whatwhat Im saying only is that if you say how much of the galaxy have we looked

at very carefully over long range of the radio dial, its a few thousand, maybe 10,000,

maybe 20,000 star systems.

And as you know, there are three or 400 billion star systems.

>>TYSON: Yeah.

Youre talking about a speck.


>>TYSON: The tiny little volume.

>>SHOSTAK: Right.

>>TYSON: Okay.


Its a fly speck on your tie.

Nobodyll notice.

>>TEGMARK: Yeah, butbut we cannot just consider thethe limits of our own technology

and say we havent looked yet, so wewe cant be sure, you know.

If you are a lizard

>>TYSON: Wait.

Is this your answer to the Fermi paradox, Max?

>>TEGMARK: Yes, it is.

Because if Im a lizard living in the rainforest, and Ive only explored 10 square meters

around where I live, and II cant just draw the conclusion that that must mean that

there isthere could be all of thisI cant draw strong conclusions about whats

elsewhere in life on Earth.


We humans have much more advanced technology thanthan the lizards, and weve come

there and screwed over the rainforest already in a really, really major way.

And where Im going with this is we also know, from our own astronomical observations,

right, that theres over 1 billion solar systems, many in our own galaxy, that seem

pretty inhabitable, and then there is another 100 billion or more galaxies in our observable


If any of those solar systems have developed the technoloa civilization with our level

of technology a billion years ago or so, right, theres nothing in the laws of physics,

if they wanted to, preventing them from building very advanced technological life andand

going out and really doing big things in our universe.

Weve talked about the history of life, mostly, so far in the panel, which is fascinating.

But I think the future of life is very interesting, too, and we pay tribute to Isaac Asimov today

and to Charles Hayden.

I just want to put in a tribute to Freeman Dyson as well, whowho left us this year,

who may be the really first serious scientific article about the future possibilities of

life in our universe.

And if I had to summarize it inin one sentence, what Freeman concluded, it was you aint

seen nothing yet.

All right?

Hehe basically describes our universe as a Sahara Desert with a little oasis here on

Earth, and maybe there is some other oases where Seth can find E.T.

But mostly it looks totally devoid ofof life.

>>TYSON: Were with you on that.

Where are you coming up with that were the only ones with telescopes?

>>TEGMARK: Yeah.

For example, andand so, so obviously, you have to ask, well, what does that mean?

And what Enrico Fermi said isis well, maybe it means that there isnt, that life is

for some reason much rarer than we thought.

Though, yeah, its hard to detect life as trying to hide from us, maybe there are, in

fact, billions of other civilizations on all of these planets there that are just all so

excited about the video games theyve developed that theyve decided to not go out and do

any large scale cosmic engineering projects and also

>>TYSON: Theyre all in their parentsbasement.

>>TEGMARK: Yeah, in their parentsbasement.

But I actually think thats a very, very unconvincing scenario.

You would only need one civilization that was like, hey, Im going to build the Milky

Way version of the Great Wall of China and start doing some Dyson spheres and rearrange

my neighborhood

>>TYSON: And, wait, Nathalies got something to say.

Nathalie, what are youwhat are youwhat are you trying to say?

>>CABROL: Yeah, and you know, of course, we can speak a little bit about soso much

around that subject.

But there is one thing, and Im not saying that this is necessarily where my heart is

going in terms ofof theories, but there might be something to be said about the possibility

of generational aspect of life, which means that it may be, if we want to be really anthropocentric

here, that the type of star or the type of material thats creating life as we know

it is just, you know, coming ininto life in the universe right now.

And basically, we are the first incarnation, manifestation of the type of life that we

can recognize and can communicate with, and it will take a little bit more time.

Look at us only 100 years ago or 200 years ago.

The fastest way of going from Point A to Point B was the fastest horse you could buy.

And now we are shooting spacecraft into space.

So I am not saying this is the right theory, but there might be something like that.

>>TYSON: Right.



>>CABROL: [Indiscernible] somewhere that there was probably a lot more [indiscernible] bacteria

in the universe than there is actually an E.T.

>>TYSON: Carol, you wrote a book on the universality of life as we dont know it.

Did I get that title correct?


It was called The Quest for a Universal Theory of Life, but its about that topic.

But I want to go back just briefly, because I think its really important, to intelligence.

Philosophers normally distinguish intelligence from sentience or self-awareness.

And sentience and self-awareness have to do with the subjective point of view, this capacity

of us to see the world as a unique point of view.

And so, thats whats really hard to define.

I think that could characterize.

Our philosophers are still struggling with understanding what it is to have a mindnot

just intelligence, but to have a mind.

And so, I just wanted to mention thatthat intelligence is not necessarily the same as

being conscious or sentient.

So I just wanted to mention that, but you asked

>>TYSON: Okay.


Thank you.

Seth, Seth, youve been trying to jump in.

>>SHOSTAK: Yeah, [just very quick].

II have to respond to Max, because hes essentially saying that theres no point

in my career here.

>>TEGMARK: Oh, no, no, no.


>>SHOSTAK: Im going to take a paper route, Max, but I will say that I have to admire

your audacity, because after all, what youre saying is, okay, were the smartest things

in the cosmos, and, you know, thats great, but isnt it a little self-referential?

It could be that maybe your parents were a little too doting, right, and then they convinced

you of this idea.


>>TEGMARK: I would much rather, of course, have a universe which is much more alive.

First of all, I love what youre doing with SETI, and I love what everybody on this panel

is doing for the professional job.

When I say Ill bet you that we are the first life thats built telescopes, that

means more than 50%.

It doesnt mean 99.999%.

Of course we should look.

It would be the most important discovery ever if we find it, right?

But we need to be humble, also, and we cant just dismiss this by saying, well, you know,

maybe its too early in our universe for any of this other stuff that

>>SHOSTAK: No, no, no, no.

>>TEGMARK: …a late bloomer solar system.

We know that already.

>>SHOSTAK: The universe has had

>>TEGMARK: There are a lot of [indiscernible] in our galaxy, right, which have been here

for over a billion years longer than us.

So if most of them got as far as we did, it would take less than a million years for them

to spread life throughout our galaxy and do all kind of cool stuff, which they havent.

And I thinkI would just want to come back to Freeman again, because I think theres

a great optimism inin what he says.

Its like youre looking out over the Sahara Desert from your oasis, and Freeman

Dyson is saying it doesnt have to be this way forever.

One day the Sahara can blossom with all sorts of life, right?

>>TYSON: Its called global warming.



>>TEGMARK: And maybe its on us, actually.


>>CABROL: It was very green 2,000 years ago.

>>TYSON: Yes, exactly.

>>TEGMARK: …for some lucky reason, and its up to us to try to not go extinct, andand

maybe wemaybe their

>>TYSON: Max.

>>TEGMARK: …first extraterrestrial life on other solar systems [indiscernible]…

>>TYSON: Just to summarize, youre saying that youre content with the answer to the

Fermi paradox that there is no truly advanced civilization out there.

Soso there could be one, or theres not, but theythey encounter the same challenges

we would have to populate the galaxy.

Thats what youre saying.

>>TEGMARK: And also, though, Im saying that these challenges are much smaller than

we thought when you now factor in artificial intelligence.

We dont have to wait for human minds to invent all of the clever

>>TYSON: Let the machine do it.

Vera, what were you trying to say?

>>KOLB: I just wanted to throw monkey wrench into discussion.

>>TYSON: No.


>>KOLB: Im citing a very exciting paper

>>TYSON: Oh, wait, she froze up again.

>>TEGMARK: Those Martians.

>>TYSON: The Martians keep interrupting her communication.

>>CLELAND: Martian censorship.

>>SHOSTAK: Well, but one thing to note about what Max has said, theres no way for him

to prove himself right, but there is a way to prove him wrong, right?


>>TYSON: Yeah.

>>CABROL: Seth is trying to save his job.

>>TYSON: Okay, wait.

Vera is back.

Vera, youre back.

>>KOLB: Am I?


>>TYSON: Vera, you froze up there for a second.

>>KOLB: I just wanted to bring up for Max to contemplate an idea of directed panspermia,

which Leslie Orgel and Francis Crick proposed in 1970s, and they were initially ridiculed

for it, but now everybodys sort of thinking about it.

Namely, that life spread through the universe by intelligent bees who sent, essentially,

samples of life around in their spaceships of other means.

And I think now, since we know about space travel, this became more interesting, because

Orgel and Crick felt that life was a rather rare event.

And so, maybe some very intelligent planet, population, advanced technological population

came up with this way to transfer life elsewhere through the universe.

>>TYSON: So there, Max.


>>TEGMARK: I think we have a moral responsibility to not dismiss the possibility thatthat

we have this amazing responsibility on our shoulders, because I think were really

reckless, frankly, with how we take care of our planet.

Were really terrible

>>TYSON: You think?

>>TEGMARK: …take care of it.


And if they just tell us thats okay, if we go extinct because there are all of these

other civilizations, we know theyre going to bail us out, then we are, like, even more


I think we should be open to the possibility that maybe the destiny of life in our cosmos

is up to us, andand be better stewards of the oppof the Earth we have.

>>TYSON: So were running short on time.

I just want to make sure I hit a couple of things.

So, Nathalie, you have a bookyou wrote a bookor coauthored a book on habitability

on Mars?

Is thisdo you want to terraform Mars?

Whats your objective with


No, absolutely not.

In fact, its a collection of chapters where we are talking about the past habitability

of Mars and the potential for life on Mars at the beginning of the history of Mars.

>>TYSON: Okay.

Very good.

>>CABROL: So this is really a book thats looking at, you know, the potential for missions

like Curiosity, where they should be looking at what type of environment, etc.

>>TYSON: To find the life that might have been there back when it was a

>>CABROL: Yeah.



>>TYSON: A fertile haven.

Very excellent there.

Andand, Carol, you have to tell meCarol, you have to tell me about youryour universal

theory of life inin 90 seconds.

>>CLELAND: I dont have a universal theory of life.

What I do is I try to discusspeople have been searching for a universal theory of life

since Aristotle.

Aristotle thought he had a universal theory of life.

And I argue, in my book, that biology is the only field that is still wed to fundamental

Aristotelian distinctions, namely Aristotle distinguishedhe distinguished, basically,

what we think of as metabolism, the ability to self-organize and maintain self-organization,

and the ability to reproduce, which nowadays, we have added, of course, with Darwin, with

a hereditary system.

And so, were stillif you look at theories of the origin of life, they divide along those


If you look at theories of the nature of life, they divide along those lines.

And if you look at chemistry, we got rid of Aristotles, you know, fiveAristotle

thought fire, earth, wind

>>TYSON: Elements?

>>CLELAND: …yeah, go on and on.

And same with the ideaAristotelian idea that rest is the natural state of motion.

And it was getting rid of those Aristotelian ideas that actually led to the flowering of

the physics and also chemistry.

And yet, here we are in biology, still wedded, as revealed in theories of the origin of life,

nature of life, to this bifurcation of fundamental characteristics of life.


>>TYSON: Everybodys stuck.

Theyre stuck is what youre saying.

>>CLELAND: We need to go beyond the Aristotelian concepts.

We need to do what physics and chemistry did.

>>TYSON: To unify.

>>CLELAND: Well, not to unify, but to think ofto consider the possibility that our

foundation, for thinking about life, is fundamentally mistaken.

>>TYSON: Fundamentally mistaken.

Well, let me end with one final questionNathalie, what is your favoritethis is, like, for

Seths benefitNathalie, what is your favorite Hollywood alien, and why?

>>CABROL: I am totallyI am a sucker when it comes to that.

I am a romantic, so I go for E.T.

>>TYSON: E.T., ooh, E.T.

Very good.

By the way, Steven Spielberg told me that when he created that character, that character

was a vegetable rather than an animal.

And even though we want to think of it as an animal, because it walked and talked and

had fingers and things, but notice how good it was with plant life.

It could touch plants, and the plants would come back to life.

So inin his original thinking of that entity, it was a plant rather than an animal.

So, Vera, whats your favoritewhats your favorite Hollywood alien?

Cant hear you.


>>TEGMARK: The Martians.

>>KOLB: Also E.T. for three reasons.

Its cute, its friendly, and there is a great representation of planetary protection

during this movie.

Soand also, no violence.

It is just very friendly.

In another emotion of E.T., he is lonely for his home.

So that is a very nice feature that I like very much.

>>TYSON: And for those who dont remember the film or never saw it, the planetary protection

is they set up this zone with these sort of hazmat outfits when they had to operate on

E.T., because they thought E.T. had died, but of course, he didnt, because its

a Steven Spielberg movie.

Soso, Carol, whos your favorite Hollywood alien?

>>CLELAND: E.T. is not my favorite.

Hes very anthropocentric in terms of a character.

The Horta in Star TreksDevil in the Darkis my favorite, because it wasnt

until they had a Vulcan mind meld of all things and discovered it was a mothertalk about

anthropocentricthat was protecting its young that it suddenly was thought to be conscious

and sentient and worthy of saving.

>>TYSON: So the Horta was the silicon-based life that basically just looked like a rock.


>>TYSON: Silicon being one of the active ingredients in so many rocks.

And I remember that the babies were these perfect, spherical eggs, but they were just

rocks, right?

>>CLELAND: Right.

And nobody would have ever thought, if it hadnt been for the Vulcan mind meld and

the discovery of its anthropocentric characteristicsactually, [narmalien]…

>>TYSON: [Narmalien], yeah, protecting its young.


>>CLELAND: Yeah.

>>TYSON: Right.


>>CLELAND: No, it was quite

>>TYSON: Very cool.

Very cool.

And, Seth, what do you have?

>>SHOSTAK: Yeah, well, E.T. is

>>TYSON: No, I want to come to you last

>>SHOSTAK: Oh, okay.

>>TYSON: …because youre the alien finder.

Max, whats your favorite alien?


>>TEGMARK: Im going to goIm going to go with the aliens in the movie Contact.


>>KOLB: Yes.

Thats a good movie, too.

>>TYSON: Thats a little bit of a cop out, but Ill go

>>TEGMARK: No, but Ill explain it.

Its because Im always a critic

>>TYSON: A little bit of a cop out.

>>TEGMARK: …when I see aliens, because theyre soeither so anthropomorphic oror so

in violation of the laws of physics.

What I loved about the aliens in Contact is you dont see them, so I didnt cringe.


>>TYSON: Okay.


>>SHOSTAK: Yeah.

Well, III got to say, I didnt know that little E.T. was actually a vegetable.

I dont know if anybody else here is old enough to remember The Thing, a 1951 film,

where The Thing from outer space was also a vegetable.

They finally parboiled him with electric current.

But mymy favorite is the alien from Alien.

I thought he was just great, and that may be because, you know, I have an uncle who

was a dentist in Queens.

>>TYSON: And

>>SHOSTAK: All right, if you have to think about it, its not even worth thinking about



>>CABROL: Or maybe ALF.

>>TYSON: Oh, ALF was kind of fun, with a sense of humor, too.


>>SHOSTAK: Yeah, but he didnt have the bottom of his body.


>>SHOSTAK: He didnt.

>>TYSON: You had to imagine it.

Can I tell you my favorite alien, just speaking as an astrophysicist and as a scientist, I

have to say The Blob from the 1958 Steve McQueen movie.

Theres one that is not anthropomorphic at all.

Its got nono spinal column.

Its got no mouth, eyes, hands, fingers.

Its just The Blob.

And most people dont remember that when The Blob landed on Earth, it was completely


Only after it ate its first human did it turn red, and it was red for the whole rest of

the movie.


>>TYSON: So this was athis was a creature that defied any biological understanding of

any way life could have been.

And so, thatsI think of that every time when I want to wonder what exotic alien life

might be.

Well, panel, this has been highly illuminating and fun, and its great to see all of your

expertise coming together in angular ways to enlighten our audience.

And so, I just want to sort of give you an applause for that.

[applause] [music plays]

The Description of 2020 Isaac Asimov Memorial Debate: Alien Life