(dramatic music)
Since the very beginning of time,
man has looked to the night sky
and asked the same questions.
Where are we?
How far do the stars go?
And are we alone?
(dramatic music)
Today, these same questions linger in the minds
of every human with an inquisitive nature.
Is our world just a speck in an infinite universe,
surrounded by many other worlds and species,
or is it possible that we are the only intelligent life
in the universe?
(dramatic music)
If our universe is truly infinite
then it is thought that anything that could happen
has happened an infinite number of times.
There will be infinite worlds
and infinite intelligent life forms,
even infinite copies of ourselves,
(dramatic music)
but we may also exist in an infinite universe,
which is one of infinitely many universes
each existing in possibly infinite dimensions.
(dramatic music)
We will explore the many theories and ideas
as to where we all are in this immense system,
which seemed to come from nothing
in the Big Bang 13.8 billion years ago.
(dramatic music)
New understanding says this may not be the full story.
We look at the ideas and theories from a human perspective
and hear from our best scientific minds,
who spend their lives trying to understand
these monumental concepts.
How do we try and understand
what may be simply beyond human comprehension?
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(radio static)
Are we the only life in the universe?
Given that the universe is thought to be spatially infinite,
then it would seem impossible that our world
is the only world to have started life.
If life exists elsewhere in the universe,
then will we ever meet another intelligent race?
Unfortunately, we have to go back
to the sheer scale of the universe
to realize that even our closest neighbors
would take many light years to reach.
(dramatic music)
Life could exist in so many forms
that we would not even recognize it to be a living entity.
Life might be so short-lived that it has come in
and out of existence in less time
than we can conceive of it.
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Or so vast and old that it is part of the universe itself
without us even knowing of its existence.
(dramatic music)
Life could exist in different dimensions to ours,
and again, we will never know of its presence.
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As humans, we yearn to know
if we're the only intelligent life,
but what would it mean if we did discover
another superior life form?
We consider ourselves to be sophisticated,
intelligent beings, but to another more advanced race
we could appear to them as ants do to us.
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At the heart of all human is the fear of being alone.
I hope there is more out there than just us,
because otherwise it kind of makes us assume this big ego,
and I think we have taken on this big ego of that
we are all there is and we are all that will ever be.
Maybe it's stupid that we are thinking
that there only is one world where we are living in
because it's infinity, so maybe it's like thousands
and thousands of miles away.
Another world with other people on it
and we cannot reach them or see them,
but maybe they're out there.
(dramatic music)
In an infinite universe, other life has of course,
got to exist, everything has got to exist.
But whether there's other intelligent life out there,
that becomes a much more difficult question.
I believe that there's more than we can see now.
Maybe aliens, I don't know,
because we also popped up in once with the Big Bang,
so they can also be on the other planets.
Maybe they are hiding from us, you don't know.
Do they don't wanna show themselves?
We certainly are not the only form of life.
We just can't be, not when you look at the vastness
of what is the cosmos.
The universe is filled with stars and galaxies,
and super massive black holes.
The universe is filled with dark energy
that we're not really sure what it is.
Maybe dark energy is some type of alien
that we haven't figured out what it is.
All the aliens have evolved into
dark matter, virtual particles
and they just fluctuate around and talk to each other
and do whatever they do, and we just think
it's the structure of the vacuum.
In the 1960s, an equation was formulated
to try to answer the question of the probability
and frequency of contactable intelligent life in our galaxy.
It was called the Drake equation
and it predicted that there would be conservatively
4,000 planets with intelligent life in our galaxy alone.
Since then the estimate of this figure has increased
by an amazing amount.
What is our new understanding of the possibility
that there is other life in our universe?
I think the prospect of life out in the universe
is reasonably high because the conditions here
and the conditions out there
are probably gonna be quite similar.
I mean, we would expect similar chemistry,
we'd expect water, et cetera.
It's probably tricky to get exactly the right conditions
to get life going, so it's unlikely to be
absolutely everywhere, but I wouldn't be surprised
if there is other life around in our own universe.
It would be a kind of massive freak in a way,
if the only place where there was life happened to be
here on Earth.
The universe is infinitely large, then one of the things
that can happen appears to be life.
And so unless there's something really special about us
and there's really no physical evidence anyway
that we're special, then yes, intelligent life
should exist elsewhere.
Life perhaps more intelligent than us cam exist elsewhere.
If it really is spatially infinite,
then I am certain that we're not alone.
If it's spatially finite, I'm just almost certain
that we're not alone.
Almost certain why?
Well, for all the usual reasons.
Because there are plenty of planets in the Goldilocks zone.
As we start to look for the planetary bodies,
every star we've looked at over the last decade
has turned out to have planets around it.
We already discovered a few relatively close stars
that have planets roughly in the Goldilocks zone.
And that's just from a tiny sample.
So there must be very, very many of them in our galaxy.
And our galaxy is only one of an incredible number
of galaxies in the bit of the universe that we can see.
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So if nothing else,
the sheer size of the universe makes it hard to imagine
that we are the only example of intelligent life to date
and the more we improve our technology and telescopes,
the more we can see the vastness of the universe
has only just started to reveal itself.
10,000 years ago, we had Earth, we had the Sun.
We had other things in the sky which appear to be stars.
We didn't realize that those stars were actually
new solar systems.
And nowadays we pretty much know
that every star in the night sky has at least a planet
and if not more.
So if our galaxy alone has 300 billion stars,
there's probably at least 300 billion planets.
So there's lots of planets out there.
(dramatic music)
Even the finite universe that we see is vast.
Number of stars in the sky just in our one galaxy
is hundreds of billions.
(dramatic music)
But then we realize there's actually other galaxies
that contain billions of stars.
And those stars each have planets
and those planets each may or may not have life.
So then we have a large thing which we call the universe,
which has 175 billion galaxies with all these stars
and all these planets.
(dramatic music)
In the last decade,
we have found so many alien worlds,
exoplanets around other stars
that we can be pretty confident that on average,
every star in the night sky has a planet.
If you run the numbers, it's potentially four billion
Earth-like worlds in our galaxy alone.
So to say that ours is the only place that life has arisen
is to take a four billion to one gamble.
Now, those odds seem pretty, pretty steep
and I am not a gambler, even if I were,
I think that might be a bit of a punt,
a bit of a stretch too far.
One of the variables in the Drake equation
that has given the formula a lot of criticism
is the number of times life starts on other planets.
I don't even have to go with infinite for life.
I think with almost certainty that we are not alone,
that there is life in our galaxy.
It is a theoretical possibility
that we are the only life in the universe.
And we still don't know of any other life forms,
no matter how crude.
So is life starting on other planets a likely probability
or an incredibly rare occurrence?
(dramatic music)
Recently we analyzed data from the Kepler space telescope.
We analyzed stellar systems that have multiple planets.
And we predicted how many planets
would be in the habitable zones around other stars.
So when you look up at night, you will see a star,
our results tell us that this should be on average
about two planets in the habitable zone.
So that implies that there's a lot of real estate,
a lot of things that are vaguely like the Earth,
rocky planets with some water on it.
So rocky planets with water on it
are everywhere in the universe, everywhere,
probably an infinite number of them.
And the carbon and water is everywhere.
Amino acids are everywhere.
Matter of fact, they're falling from the sky right now
in carbonaceous chondrites.
So the ingredients for life are everywhere
and not just in the origin of our Earth,
but in the origin of all the earths, the infinite earths
that I just referred to.
But now comes the question, should we expect life there?
Well, there doesn't seem to be an ingredient bottleneck,
but maybe there's what you call a recipe bottleneck.
Maybe there had to be some very unlikely coincidence
of this coming into contact with this,
and then it had to be sulfur spring going on here,
and then you have a tide going here
and you had to have dehydrate.
In other words, such a complicated recipe
in that life is very, very rare.
And therefore we don't see any aliens
that have conquered our galaxy.
I think life has to exist somewhere else.
Now, firstly, we have to think of what life is.
So bacteria, plants, animals those are all life.
I would say it it's nearly guaranteed
that some form of life exists
in our own solar system right now.
If you look at Titan, the largest moon of Saturn,
it has liquid ammonia, so it has rivers and lakes
essentially of ammonia.
Now we can't live off of that, but there's no reason
you can't have something else that does.
With Mars and the polar ice caps, I believe that we'll find
evidence that life has existed at some point on Mars,
well within at least a decade, if not sooner.
So that's just our little, very, very, very, very,
very small clump of our galaxy,
which is just one of 175 billion.
If you look at mathematically, it has to, has to exist.
But how does life start?
Some new ideas suggest that asteroids
are like planet-seeding systems that carry the formula
for life around the universe.
But if that isn't the case, then chemistry evolved
here on Earth in what has been termed the primordial soup,
but we still don't know for certain.
It seems unlikely that we are very, very improbable,
and so the best guesses are
that there are many other civilizations in our galaxy.
But you get back to the question, what causes life?
We don't know.
We don't know how life starts.
But we do know that life started on our Earth
fairly soon after the Earth cooled down,
which suggests to you either life starts fairly easily
or else there's some divine intervention.
Again, all bets are off there's divine intervention.
Life seemed to start on Earth
as soon as the Earth cooled down.
This does suggest that life is relatively easy to start.
But this is a sample size of one.
Until we confirm another life form,
we still don't know for sure.
(dramatic music)
Life appears to have emerged here on Earth,
pretty much as soon as the conditions
were even vaguely hospitable.
So, if life emerged so quickly on Earth,
maybe it is simple for it to emerge elsewhere.
I actually think life might be
relatively easy to kickstart,
because we don't know the exact mechanism
by which life arose, it's very difficult to put a number.
My suspicion is it might not be as hard as we're thinking
and potentially a lot of these habitable worlds
could well be inhabited.
Now whether that life can communicate,
whether it's intelligent life, again,
it's just unknowable until we detect it.
One of the exciting things with astronomy at the moment
is that we're really legitimately looking now
for life on other planets.
And it's something that within a decade or so,
there's a very good chance that we might be able to measure.
And I'm not talking about
listening for radio signals from aliens.
What I'm talking about is looking at
the atmospheres of planets that exist around other stars
and looking for traces of life in those atmospheres,
things like oxygen, which we know is unstable.
If you have O2 then it has to be being created by something
because it's very unstable, it will rust, it will burn,
and it won't hang around for long.
So if you can see something like O2 in the atmosphere
then something's producing it and that thing could be life.
(dramatic music)
Intelligent life is still
one of the big questions for us to answer.
As yet, all the searching we have done has only shown us
what a vast, lonely place the universe appears to be.
But other intelligent life could take many forms
and looking for versions of ourselves
could be entirely the wrong approach.
So, we'd like to know how convergent human life is,
or whether we should expect humanoids on other planets.
For example, if there's an infinite number
of life forms out there, what is their diversity?
How different will they be from us?
Some biologists think that they will be
completely different, there's not a remote chance in hell
of finding a humanoid out there,
like the do every week on "Star Trek."
Other biologists think that no,
there are convergent features that produces humanoids
and produce an elephantoid or produce a dogoid,
and again, and again, and again.
So if we go back 500 million years
and then let it run again, we will find similar species
again and again and again.
Other biologists say, no, if you run the tape of life again,
you will get very, very different things every time.
So the branching of life is very uncertain.
At any point, life could take a turn
from one species to another.
In another world, man may never have evolved
past the ape stage.
So what is the likelihood of another human species
on another planet?
How unlikely are we?
Are we infinitely unlikely?
I don't think so, but I don't know so.
So the question is how often is there life out there?
There's reasons to go out and look for ET,
because that would kinda prove it.
On the other hand, it's worthwhile contemplating
whether or not we might be it.
And so that is a question we can go out
and answer by literally looking what's going on
on other planets and seeing if there are signs of life
and then looking out and listening and seeing if we can hear
the moral equivalents of ourselves.
I don't know what the likelihood is of us finding something.
The universe is very big, it's very hard for humans
to even find ourselves.
We've only existed for 100,000 years on a planet,
and so that's like in a 24-hour day,
two seconds, in a 24-hour day.
And of course we've only been able to send radio signals
and receive them for 40 or 50 years to any degree at all.
The human species is in its absolute infancy
in terms of being able to be detected
by other intelligent beings.
The first signs that we existed, were our first radio
and television signals.
Wonderful new Westinghouse television set,
with just one hand like this.
Children of course loved that film.
Hiya, Red Riding Hood, where you going?
About the whitest white.
(woman screams)
♪ Every time I see you standing there before me ♪
These signals have only just begun
in the time scale of the universe.
The first strong radio signals that humans broadcasted,
our first radio waves that have been going through space
and traveling, have only reached 11,000 stars
and there are about 300 billion stars in our galaxy alone,
and there's 175 billion galaxies.
We haven't even touched a percent of a percent of a percent
of a percent of communicating with these people.
So even if they have just gotten a radio broadcast
from the 1900s, they then have to return that signal back,
so we're gonna be waiting hundreds of years.
And this is the problem.
The vast distances of the universe
make it impossible to communicate
with even our closest neighbors.
Unless another form of communication is discovered
then our efforts to communicate are unfortunately
still in the science fiction realm.
This it seems is like the ultimate tease,
as our best science tells us
that the universe must be full of other intelligent beings.
The worry of course is that these things
are so widely separated that we'll never meet
these other creatures.
(dramatic music)
So it might be that the universe is infinitely big,
in which case there's gonna be lots of civilizations
that are just far, far too far away
to ever get in contact with us.
You know, we'll be totally outside their light cone even.
I see no doubt that every galaxy has at least one planet
with intelligent life like us right now.
So that's like 175 billion right there.
But we're never gonna be able
to talk to these people, unfortunately.
The same physics that we use to figure it out
that they're there tells us it's gonna be too long
to talk to them or travel to.
Not to say that we can't figure out something new to do.
But aliens may be much more advanced than us.
They may have found a way to travel
faster than the speed of light.
So if they exist, why have we not heard from them?
Is it possible that civilizations
only exist for a short time
and therefore finding an intelligent civilization
in our neighborhood that is in the technological stage
of its evolution is maybe just too rare,
akin to finding a needle in a haystack.
So maybe life on this planet has actually emerged
at the earliest point that it could in our galaxy.
In which case, why haven't we heard from anybody else?
Because they've only just started as well.
We've only been around for two million years
out of four, four and a half billion years on this planet.
So lots of planets could have had life at different times
that we have never experienced or never will experience.
The universe is almost 14 billion years old,
so you could have had advanced civilizations
that lived 1.3 billion years ago
and have long disappeared.
Maybe we'll disappear within a few hundred thousand years
at the rate we're going, maybe much less.
So I think life could be all through the universe,
but for a practical person, I'd ask a different question.
What's the likelihood that we'll ever have contact
with another form of life?
That's a very different question.
And that now gets us to the finite speed of light.
The speed of light is not infinitely fast,
so if you were to try to communicate to anyone
within some distance, you wouldn't get very far.
That signal would have to travel for thousands of years
to have much chance of making contact with intelligent life.
So you'd have to be around a very long time,
maybe thousands, maybe tens of thousands of years
as an intelligent race, advanced race,
to have any chance of contacting these other forms of life.
So there's two questions there.
Does life exists throughout the universe?
I'm sure it does.
Is the life contactable?
Could you make contact with it and communicate with it
in a reasonable timeframe being thousands of years?
I think the chances are very, very small, if not zero.
So communications seems impossible as yet.
But what about traveling to the stars
to discover new worlds?
One obvious drawback to this idea
is that our lifespan is simply too short.
A trip to Mars, our local planet, will take four years.
A trip to our closest star will take over 150 years.
So again, still seems delegated
to the science fiction realm for now.
But anything is possible given enough time
in an infinite universe.
We'll probably never experience
another intelligent life form, unfortunately.
So I believe that intelligent life form exists.
Maybe it doesn't look like exactly
what we think of in the movies, but maybe it does.
Maybe they're identical to me and you.
So perhaps life is a common occurrence
in the universe, but what about human life?
How rare could it be?
And if not human life,
what other kinds of diverse life could exist?
How about human-like intelligence?
If there's all this life elsewhere,
they would surely get intelligent, build spacecrafts,
and then colonize the entire galaxy.
There's been plenty of time to do that,
but we don't see spacecraft around here,
or we don't see alien signals when we listen
with the radio telescopes.
Well, that might be that maybe human-like intelligence
is not something that is a natural part of evolution.
There are many millions of other species on this planet
and they are not evolving to become human-like.
They don't wanna become human
any more than we wanna become an elephant.
Chimpanzees don't wanna become humans,
humans don't wanna become chimpanzees.
There's a relativity there, it's not human superiority.
And so humans are not some type of
convergent feature of evolution.
So, that might be to explain why we don't see all of these.
There could be life everywhere,
but it wouldn't be space-faring,
it wouldn't produce radio signals.
Or maybe it does, but then it gets so fancy,
they build all kinds of bombs, have big wars,
and they killed themselves.
It's the self-destruction bottleneck.
So, there's many scenarios you can think of
that are consistent with no visible aliens
and lots and lots of habitable planets.
(dramatic music)
Two billion years ago, we literally were amoebas
and we evolved over two billion years
into what we are today.
So, if you imagine that something similar happened
on other Earth-like planets
and they have had two billion more years to evolve,
then they'll looking at us and they're thinking,
hey, we're amoebas and we don't even understand
what they are, or no hope of talking.
You don't talk to amoebas.
And so maybe that's the situation we're in.
And that's why we think there's
no other life form in the universe.
What if life is everywhere in our universe,
but it is so unrecognizable to us
that we don't even realize it.
Could life exist on such small, quantum levels
that we can never see it, or such huge scales that again,
we could never perceive of it.
Is it possible that the universe is filled with aliens
that we just don't know about because they're made out of
dark energy for example, or they communicate with neutrinos,
or they communicate with radio wavelengths
that are so long that we don't know about them?
Well, you can easily imagine that, you know,
before 200 years ago, we didn't have radio communication.
So imagine if the universe were filled with
radio-communicating civilizations.
We wouldn't even know it until we invented the radio.
Ditto for any other technology you can think of.
But what if we did have communication
with another intelligent life form?
This has been the stuff of science fiction
for the last century.
And in most cases, the plots portray a fear of the unknown
and war with the aliens ensues.
Is this indicative of our likely behavior?
Are all aliens to be feared, or would we take a more
intelligent, scientific approach?
(dramatic music)
If they were conscious beings, then that would be
such a threat to humanity because we have
this assumed ego that we are all there is.
Anything that is unknown is a threat
to our stable, fragile existence.
You know, I think it would be vastly exciting
to be able to try to understand life forms
that were massively different to us.
We've evolved in a very particular way,
but other forms of life might have done
something totally different.
And that would be quite exciting
if we could indeed wrap our minds around it.
It's actually very difficult to get your head around
what the possible implications would be of discovering
and communicating with some other sort of alien life form.
I think that people would be incredibly excited
and it would change people's way
of thinking about their lives and their role
in the sort of universe.
While humans on the Earth are kind of the top predator
and we pretty much do what we like, whenever we like,
and there are serious consequences arising from that.
But nevertheless, you've gotta think,
we wouldn't be the top predator necessarily
when we start discovering other intelligent life forms.
And you know, it might turn out that things don't go
entirely our way.
The discovery of life, intelligent life,
somewhere in our universe, our galaxy,
would be at once the most terrifying thought
and yet most satisfying and relieving discovery,
simply because the burden of keeping this unique,
wonderful phenomenon of life
and all of its infinite variety and possibilities
is no longer ours alone to carry.
An asteroid could come and wipe us out.
The Sun will one day eventually sterilize the Earth
by expanding towards the end of its life.
And right now that burden is on us
and we're doing a terrible job of it.
We are not very good custodians of this.
But if there were aliens out there and they were intelligent
and they were able to spread between the stars,
then suddenly you would think, well, I guess it's not so bad
that us humans are kind of dropping the ball on this,
this idea of trying to sustain life
as a very beautifully weird and unexpected consequence
of basic laws of physics and chemistry,
but with infinite possibility, where the laws of physics
are essentially boring and restrictive.
(dramatic music)
From a scientific point of view,
I would want to know what their science is
to see how theirs compares to ours.
Do they describe electromagnetic radiation
in the same way we do?
Do they know about the existence of electrons
or whatever, you know?
Is there something they're doing that we're not?
I personally think that we've already
detected life elsewhere and we just don't recognize it.
And you do this by generalizing the definition of life.
If you define life as a far from equilibrium
dissipative structure, then you include fires
and whirlpools and hurricanes as part of life.
I think when we realize that we will then consider
we've already found life,
but that's a little bit of a mind bend,
that's more of a mind bend than most people
are willing to entertain,
and so they're much more happy with thinking
that maybe dark matter is aliens
and that they have big brains and they talk English.
What is life?
This is a question that is surprisingly hard to answer.
The definition of life has science divided,
some going as far as suggesting the weather
to be a form of life.
What is the purpose of life, if there is one
from an evolutionary point of view,
or is life purely a by-product of random chemistry?
I think life is that, well, you're not dead obviously,
but I kind of think that life is that you're breathing.
I think that, um.
I dunno, that's a difficult question.
What is life?
I believe life is about being a servant to other people.
I believe that this life on Earth is just like
a mini reflection of what we're gonna do
in heaven for eternity.
I think the meaning of life is a journey
that you make of that life, that gives that life meaning.
Life matters because it's an adventure.
For good or bad, there's always growth in life.
And if we're infinite beings, we're infinitely growing,
we're infinitely trying to have experiences
that we benefit from.
What is life?
Life is something that we define here on Earth.
It's hard to define.
As a matter of fact, if you go to the biology department
and ask biologists are viruses alive?
You know, half of them will say yes
and half of them will say no,
and another third will say, huh.
So we're not quite sure whether viruses are alive.
And I take that as a warning signal,
big red warning signals saying,
do we really know what life is?
'Cause if you think viruses are alive,
then they outnumber all other lifeforms on this planet.
And if you think they're not alive, well,
then you're excluding the thing
that outnumbers all other lifeforms.
(dramatic music)
When we think about life, we think about things
that have properties that are kind of like us.
So, we're very good at detecting kind of
middle-sized, living things.
We see elephants and we're pretty clear
that they are kind of living things like us.
And then we start to learn about things
that are a little bit smaller.
At some point we discover there are kind of molecules
and bacteria, and they're a little bit more difficult
to get your head around because they're so small
and they're really very different from us,
but we kind of, we manage it.
But of course there might be things that have lives
just so radically dissimilar to us
that it's hard for us to even
recognize them as having lives.
(dramatic music)
I'm a scientist, so I think there was
some type of molecular evolution,
which led to auto-catalytic processes,
which led to replication, which led to some type of,
hey, I'm gonna preserve myself
and then et cetera, et cetera, Darwinian evolution.
If you have that type of notion, then you have a way to,
at least hand-wavingly describe
how non-life evolved and life emerged.
Well, here's the thing.
Where do you grow this boundary from non-life to life?
And if this evolved naturalistically,
is there a boundary that we should put there
and say, oh, this is life and this is not life.
I think the answer is no.
It's a little like, you know, you have a mother
and you hold your mother's hand
and she holds her mother's hand,
and Richard Dawkins pointed out that
here's this train of mothers and going into the past,
and if you go back four billion years,
you're essentially having one bacteria
hold another bacteria's hand, right.
And so the question is, well, where in this chain
do you cut it and say, here's a human being
and here's the pre-human being.
Therefore, you can't put a boundary and say,
everything on this side is life
and everything on this is non-life.
That's a silly idea in the light of evolution
and I think we should get rid of it.
Now we realize that actually the fundamental reason
or point for a lot of what we see around us,
is simply for that animal or organism
to have more offspring.
That's actually it.
The meaning in life is self-replicating molecules.
That's what life means.
Life means molecules that managed to self-replicate,
some subject themselves to evolutionary processes.
I suppose that's what life is.
Life is an incredibly complicated, chemical reaction.
And the fact that you and I have the experiences that we do
and have the lives that we do is all a massive by-product
of that fundamental, simple thing,
chemistry that locally creates order
at the expense of globally creating disorder.
Our brains are a by-product of an evolutionary pressure.
In other words, to get smarter meant
that you would have more babies,
so there were more smarter babies.
That drive has led us to these wonderful, adaptable,
inquiring minds that have now unlocked
so many of the mysteries of our universe.
That to me gives a point to one's life,
to inquire, to understand, to explore, those give meaning,
in our interactions with our friends and our family,
those give meaning, that gives the point of life.
The fact that from your genes' perspective,
they just wanna replicate, they just want
their particular set to go on, okay,
that's maybe the underlying drive
and certainly is when you're a basic organism
like a bacteria, but as humans we can do better,
and we often do.
If you have an infinite number
of rocky planets that have wet,
you could have an infinite number of lifeforms.
The problem is we don't know what that means.
For example, no one can predict the direction of evolution.
Or if you go back, rewind the tape of life on Earth,
and let's say, hey, let's rewind the tape
and let's let it play again.
Would you get humans or would you get any of the species
that you see today?
That's a big debate in biology.
Stephen Jay Gould said, no way would you get
anything remotely close to being a human.
Another guy, Simon Conway Morris said, oh yes,
you'd get some kind of humanoid because there are valleys
in this adaption space where each species lives
and that would do it again and again and again.
(explosion booms)
Our bodies are made from billions of atoms,
which are all billions of years old.
So the saying we are made from stardust is literally true.
At the deepest level, we are the universe in human form.
Ultimately life emerged out of the universe.
And so for me, before I go to bed most nights, I sit down,
and we have a hot tub and I peer to the heavens.
And I look up at the stars.
I look at the Milky Way.
I look at the galaxies that orbit our own
and I think of the dark spots between the stars,
where there are countless galaxies.
And I realize just how rich the universe is
and how we are one small planet
around one pretty ordinary star
in one reasonably ordinary galaxy in a vast sea.
And the fact that we're able to go through
and contemplate and realize our place
and how all this order works is amazing.
It is to me the great, amazing story for humanity
and it intersects with philosophy and art,
just trying to come terms with it.
That's how humans are gonna interact
with that type of experience.
(dramatic music)