Sara Walker is an astrobiologist and theoretical physicist. Lee Cronin is a chemist. This is a conversation and debate about alien life and alien civilizations. Please support this podcast by checking out our sponsors:
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EPISODE LINKS:
Sara's Twitter: https://twitter.com/Sara_Imari
Sara's Website: http://emergence.asu.edu
Lee's Twitter: https://twitter.com/leecronin
Lee's Website: https://www.chem.gla.ac.uk/cronin
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PODCAST INFO:
Podcast website: https://lexfridman.com/podcast
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OUTLINE:
0:00 - Introduction
2:08 - Aliens
16:14 - What is life?
23:56 - Assembly theory
46:24 - Math
58:06 - Communication with aliens
1:22:59 - Evolution of the universe
1:32:17 - Creating alien life
1:39:50 - Origin of life
1:46:50 - Before the Big Bang
1:53:43 - God
2:04:00 - Goal-directed behavior
2:21:58 - Time
2:30:15 - Free will and imagination
2:45:27 - UFO sightings
2:50:27 - Alien life forms debate
3:05:35 - Robots
3:14:50 - Love and emotion
3:33:16 - Beauty in science
3:43:27 - Random questions
3:52:51 - Advice for young people
3:56:09 - Life on Earth
4:00:33 - Memory

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I don't know what it's like to be an alien.

2 alien civilizations coexisting on a planet.

When you see them and they see you, you're assuming they have vision, they have the ability to construct in 3D and in time.

That's a lot of assumptions we're making.

What human level intelligence has done is quite different.

It's not just that we remember states that the universe has existed in before, it's that we can imagine ones that have never existed and we can actually make them come into existence.

So you can travel back in time sometimes.

You travel forward in time to travel back.

The following is a conversation with Sarah Walker and Lee Cronin.

They have each been on this podcast once before, individually, and now for their second time, they're here together.

Sarah is an astrobiologist and theoretical physicist.

Lee is a chemist and if I may say so, the real life manifestation of Rick from Rick and Morty.

They both are interested in how life originates and develops both life here on Earth and alien life, including intelligent alien civilizations out there in the cosmos.

They are colleagues and friends who love to explore, disagree and debate nuanced points about alien life.

And so we're calling this an alien debate.

Very few questions to me are as fascinating as what do aliens look like?

And how do we make sense of life here on earth in the context of all possible life forms that are out there?

Treating these questions with the seriousness and rigor they deserve is what I hope to do with this conversation and future ones like it.

We must first be humble to acknowledge this and then be bold in diving in and trying to figure things out anyway.

To support it, Please check out our sponsors in the description and now dear friends here Sarah Walker and Lee Cronin First of all, welcome back Sarah.

Welcome back Lee you guys I'm a huge fan of yours.

You're incredible people I should say thank you to Sarah for wearing Really awesome boots will probably overlay a picture later on but why the hell didn't you dress up Lee?

You were saying that you're pink, that your thing is pink, my thing is black and white, the simplicity of it.

So About 2017, I think, I just decided I was boring and I needed to make a statement.

And red was too bright, so I went pink, salmon pink.

Well, I think you were always pink, you just found yourself in

There's an amazing photo of him where there's like everybody in their black gown and he's just wearing the pink pants.

Hundred year anniversary they got me to give the plenary and they didn't they didn't find that outfit for me so they were all wearing these silly hats and these gowns and there was me dressed up in pink looking like a complete idiot.

We're definitely gonna have to find that picture and overlay it, big full screen, slow motion.

We'll find places we disagree and places we agree.

Life, intelligence, consciousness, universe, all of that.

Let's start with a tweet from Neil deGrasse Tyson stating his skepticism about aliens wanting to visit Earth.

Quote, how egocentric of us to think that space aliens who have mastered interstellar travel across the galaxy would give, pardon the French, would give a shit about humans on Earth.

So let me ask you, would aliens care about visiting Earth, observing, communicating with humans?

Let's take a perspective of aliens, maybe Sarah, first.

Are we interesting in the whole spectrum of life in the universe?

I'm completely biased, at least as far as I think right now, we're the most interesting thing in the universe.

So I would expect, based on the intrinsic curiosity that we have and how much I think that's deeply related to the physics of what we are that other intelligent aliens would want to seek out examples of the phenomena they are to understand themselves better.

And I think that's kind of a natural thing to want to do.

And I don't think there's any kind of judgment on it being a lesser being or not.

It's like saying you have nothing to learn by talking to a baby.

You have lots to learn, probably more than you do talking to somebody that's

So whatever the phenomena is that is human, there would be an inkling of the same kind of phenomenon within alien species and they would be seeking that same.

I think there's gotta be some features of us that are universal, and I think the ones that are most interesting, and I hope I live in an interesting universe, are the ones that are driven by our curiosity and the fact that our intelligence allows us to do things that the universe wouldn't be able to do without things like us existing.

That's a very interesting term to try to define.

Well, let's take it from our perspective.

We wanna go find aliens as a species quite desperately.

So, if we put the shoe on the other foot, of course we're interesting.

But I'm wondering, and assuming that we're at the right technological capabilities to go searching for aliens, then that's interesting.

So what I mean is if there needs to be a massive leap in technology that we don't have, how will aliens prioritize coming to earth and other places?

But I, I do think that they would come and find us because they'd want to find out about our culture, what things are universal, what about, I mean I'm a chemist, so I'd say what is the chemistry universal, right?

Are the creatures that we're going to find making all this commotion, are they made of the same stuff?

So I think that Neil deGrasse Tyson is being slightly pessimistic and maybe trying to play the tune that the universe is vast and it's not worth them coming here.

I don't think that, but I just worry that maybe we don't have the ability to talk to them, we don't have the universal translator, we don't have the right physics.

It would make it easier if they just came

So again, I'm gonna use Your tweets like it's Shakespeare and analyze it.

So Sarah tweeted thinking about aliens thinking about aliens, so how much do you think aliens are thinking about other aliens, including humans?

So you said we humans want to visit, like we're longing to connect with aliens.

Is that an obvious thing that we should be like, what are we hoping to understand?

Asking as an introvert, it's like I ask myself this all the time Why do I go out on a Friday night to meet people?

I think the curiosity, so when I saw Sarah put that tweet, I think I answered it actually as well, which was we are thinking about trying to make contact.

So they almost certainly are, but maybe there's a number of classes.

There are those aliens that have not yet made contact with other aliens, like us.

Those aliens have made contact with just 1 other alien and maybe it's an anti-climax and slime.

And aliens that have made contact with not just 1 set of intelligent species, but several.

Literally, there are some place in the universe, there must be 1 alien civilization to not make contact with, not 1, but 2 other intelligent civilizations.

So they must be thinking about it, there must be entire degree courses on aliens, thinking about aliens and cultural, universal cultural norms.

Do you think they will survive the meeting?

And by the way, Lee did respond saying that's all the universe wants.

So Sarah said thinking about aliens, thinking about aliens.

And then Sarah responded, cheeky universe we live in.

So cheeky is a cheeky version of the word interesting, all of which we'll try to define mathematically.

I think there's a mathematical definition of humor, but we'll talk about that

So if you're a graduate student alien looking at multiple alien civilizations, Do you think they survive the encounters?

I think there's a tendency to anthropomorphize a lot of the discussions about alien life, which is a really big challenge.

So usually when I'm trying to think about these problems, I don't try to think about us as humans, but us as an example of phenomena that exist in the universe that we have yet to explain.

And it doesn't seem to be the case that if I think about the features I would argue are most universal about that phenomena, that there's any reason to think that a first encounter with another lineage or example of life would be antagonistic.

I think, yeah, and I think there's this kind of assumption.

I mean, going back to Neil deGrasse Tyson's quote, I mean, it kind of bothers me because there's a, I mean, I'm a physicist, so I know we have a lot of egos about how much we can describe the world, but that there's this like, because we understand fundamental physics so well, we understand alien life and we can kind of extrapolate and I just think that we don't and the quest there is really you know really to understand something totally new about the universe and that thing just happens to be us.

I agree I agree there's something else more profound I think Neil was just being again he's just trying to stir the pot.

I would say from a contingency point of view, I want to know how many ways does the universe build structures, build memories, right?

And then I want to know if those memories can interact with each other.

And if you have 2 different origins of life and then origins of intelligence, and then these things become conscious, surely you want to go and talk to them and figure out what commonalities you share.

And it might be that we're just unable to conceive of what they're going to look like, they're just going to be completely different, you know, infrastructure, but surely we'll want to go and find out a map and surely curiosity is a property that evolution has made on earth.

And I can't see any reason that it won't happen elsewhere because curiosity probably exists because we want to find innovations in the environment, we want to use that information to help our technology, and also curiosity is like planning for the future, are they gonna fight us?

So I think that Neil's just, I don't know, maybe, you know, I mean, give a shit, that's really, I think that's really down on Earth, right?

How would aliens categorize humans, do you think?

Maybe, no, no, no, Maybe we could, the thing is a bit odd, right?

Look at Instagram, Twitter, all these people taking selfies.

I mean, does the universe, is the ultimate state of consciousness thinking beings that take photographs themselves and upload them to an internet with other thinking beings looking at each other's photos?

I did not say there was anything wrong with it.

Yeah, I do think that curiosity is really the driving force of why we have our technology, right?

If we weren't curious, we wouldn't go out, left the cave.

So I think that, so I think that Neil's got it completely wrong, in fact, actually, of course, they'd want to come here.

It doesn't mean they are coming here, we've seen evidence for that, I guess we can argue about that, right?

But I think that we want, I desperately, and I know that Sarah does too, but I won't speak for you, you're here, I desperately want to have missions to look for life in the solar system right now.

And then I want to understand how we can go and find life as quickly as possible at the nearest stars and also at the same time do it in the lab just to compensate, you know?

If you think about sort of what's driven the most like features of our own evolution as a species, you could, and try to map that to alien species.

I always think like optimism is what's going to get us furthest.

And so I think a lot of people always think that it's like war and conflict is gonna be the way that alien species will expand out into the cosmos.

But if you just look at how we're doing it and how we talk about it, it's always our future and space is always built from narratives of optimism.

And so It seems to me that if intelligence does get out in the universe, that it's gonna be more optimism, curiosity driving it than war and conflict because those things end up crushing you.

Is it obvious that curiosity, not obvious, but what do you think, is curiosity a more powerful force in the universe than violence and the will to power?

So, because you said you frame curiosity as a way to also plan on how to avoid violence, which is an interesting framing of curiosity.

But I could also argue that violence is a pretty productive way to operate in the world, which is like, that's 1 way to protect yourself.

I'm not qualified to answer this, but I'll have a go.

I think violence, let's not talk about violence.

I would, yeah, maybe, let's not call it violence, but I call it erasure.

So if you think about the way evolution works, or the way, obviously corporate assembly theory, but I won't.

So if you say, curiosity allows you to open up avenues, new graphs, right?

The ability to erase those things allows you to start again and do some pruning.

So the universe, I think curiosity gets you furthest.

Curiosity gets you rockets that land, it gets you robots that can make drugs, it gets you poetry and art and communication.

And then, you know, I often think, wouldn't it be great in bureaucracy to have another world war, not literally a world war now, please no world, not war, but a, the equivalent.

So we get, remove all the admin bureaucracy, right?

All the admin violence, get rid of it and start again.

Because you get layers and you get redundant systems built.

So actually a reset, let's not call it violence, a reset in some aspects of our culture and our technology allows us to then build more important things without the, because how many, you know, how many cookies do I have to click on?

How many things, how many, how many extra clicks I do I have in the future of my life that I could remove and a bit of a reset would, would allow us to, to, to start again.

And maybe that's how I suppose our encounter with aliens will be.

Maybe they will fight with us and say, oh, we're not as excited by you as we thought.

To be like, let's see how the evolution runs again.

This seems like they've, there's nothing new happening here.

They're observing for a while, this is just not, let's keep it more fun.

I like how you equated violence to resetting your cookies.

In this modern world where words are violence, resetting cookies is a kind of.

What is the line between life and non-life?

And maybe at any point we can pull in ideas of assembly theory.

Like how do we start to try to define life?

And for people listening, so Sarah identifies as a physicist and Lee identifies as a chemist.

Of course, they are very interdisciplinary in nature in general.

I love asking that question because it's so absurdly big.

It's my absolute favorite question in the whole universe.

So I think I have 3 ways of describing it right now.

And I like to say all 3 of them because people latch on to different facets of them.

And so the whole idea of what Lee and I are trying to work on is not to try to define life, but to try to find a more fundamental theory that explains what the phenomena we call life.

And then it should explain certain attributes.

And you end up having a really different framing than the way people usually talk.

So the way I talk about it, 3 different ways.

Life is how information structures matter across space and time.

Life is, I don't know, this one's from you actually, simple machines constructing more complex machines.

And the other 1 is the physics of existence, so to speak, which is life is the mechanism the universe has to explore the space of what's possible.

So can I, Yeah, yeah, can I add on to that?

You know, like if you think of all the things that could exist, only certain things do exist.

And I think life is basically the universe's mechanism of bringing things into physically existing in the moment now.

So if you think about a universe that has nothing in it, that's kind of hard to conceive of, right?

Because, and this is where physicists really go wrong, they think of a universe with nothing in it, they can't.

Non-existence is really hard to think of.

And then you think of a universe with everything in it, that's really hard, and you just have this white blob, right, it's just everything.

But the fact we have discrete stuff in the universe beyond say planets, so you've got stars, space, planet stuff, right?

But I would define life or say that life is where there are architectures, any architectures, and we should stop fixating on what is building the architectures to start with in the fact that the universe has discreet things and it is completely mind blowing if you think about it for 1 second.

The fact there's any objects at all, because for me the object is a proxy for a machine that built it, some information being moved around, actuation, sensing, getting resource, and building these objects.

So for me, everyone's been obsessing about the machine, but I'm like, forget the machine, let's see the objects.

And I think in a way that assembly theory, we realized maybe a few months ago that assembly theory actually does account for the soul in the objects not mystically like say sheldrake's morphic resonance or liveness is not a monodology sing souls and things but when you see an object I said this before but this object is evidence of thought and then there's a lineage of those objects.

So I think what is fascinating is that, you put it much more elegantly, but the barrier between life and non-life is accruing enough memories to then actuate.

So what that means is there are contingency, there are things that happen in the universe get trapped, these memories then have a causal effect on the future.

And then when you get those concentrated in a machine and you're actually able in real time, able to integrate the past, the present with the future, and do stuff, that's when you are most alive.

Wait a minute, why is the object, so 1 of the ways to define life that Sarah said, is simple machines creating complex machines.

So how the hell does a simple machine create a complex machine?

So this is what we were talking about at the beginning.

You have the minimum replicator, so molecule.

So this is what I was trying to convince Sarah of the mechanism years ago, I think, but then you've been building on it and saying, you have a molecule that can copy itself, but then there has to be some variability, otherwise it's not going to get more functional.

So you have a minimum molecule that can copy itself, but then it can add bits on, and that can be copied as well.

And those add-ons can give you additional function to be able to acquire more stuff to exist.

So existence is weird, but the fact that there is existence is why there is life.

And that's why I realized a few days ago that there must be, that's why alien life must be everywhere, because there is existence.

Is there like a conservation of cheeky stuff happening?

So like how can you keep injecting more complex things?

Like doesn't the machine that creates the object need to be as or more powerful than the things it creates?

So how can you get complexity from simplicity?

So the way you get complexity from simplicity is that you, I'm just making this up, but this is kind of my notion, and you have a large volume of stuff, So you're able to get seeds, if you like, random cues from the environment.

So you just use those objects to basically write on your tape, ones and zeros, whatever, and that is necessarily rich, complex, okay?

But it has a low assemblyness, but even though it has a high assembly number, we can talk about that.

But then when you start to then integrate that all into a smaller volume, as over time, and you become more autonomous, you then make the transition.

I think the easiest way to think about it is actually, which I know is a concept you hate, but I also hate, which is entropy, but people are more familiar with entropy than what we talk about in assembly theory.

And also the idea that, like say physics as we know it, involves objects that don't exist across time, or as Lee would say, low memory objects.

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Alien Debate: Sara Walker and Lee Cronin | Lex Fridman Podcast #279