Lee Cronin: Origin of Life, Aliens, Complexity, and Consciousness | Lex Fridman Podcast #269

Lex Fridman 0:00 The following is a conversation with Lee Cronin, a chemist from University of Glasgow, who's one of the most fascinating, brilliant, out of the box thinking scientists I've ever spoken to. This episode was recorded more than two weeks ago, so the war in Ukraine is not mentioned. I've been spending a lot of time each day talking to people in Ukraine and Russia. I have family, friends, colleagues, and loved ones in both countries. I will try to release a solo episode on this war, but I've been failing to find the words that make sense of it for myself and others, so I may not. I ask for your understanding no matter which path I take. Most of my time is spent trying to help as much as I can privately. I'm talking to people who are suffering, who are angry, afraid. When I returned to this conversation with Lee, I couldn't help but smile. He's a beautiful, brilliant, and hilarious human being. He's basically a human manifestation of the mad scientist, Rick Sanchez from Rick and Morty. I thought about quitting this podcast for a time, but for now at least, I'll keep going. I love people too much. You, the listener. I meet folks on the street or when I run, you say a few kind words about the podcast a- and we talk about life, the small things, and the big things. All of it gives me hope. People are just amazing. You are amazing. I ask for your support, wisdom, and patience as I keep going with this silly little podcast, including through some difficult conversations, and hopefully many fascinating and fun ones too. This is a Lex Fridman podcast. To support it, please check out our sponsors in the description. And now, dear friends, here's Lee Cronin.

Lex Fridman 2:02 How do you think life originated on earth and what insights does that give us about life?

Lee Cronin 2:09 If we go back to the origin of earth and you think about maybe 4.7, 4.6, 4.5 billion years ago, the planet was quite hot, there was a limited number of minerals, there was some carbon, some water, and I think that maybe it's a really simple set of chemistry that we, we really don't understand. So that means you've got a finite number of elements that are going to react very simply with one another and out of that mess comes a cell. So literally sand turns into cells, and it seems to happen quick. So what I think I can say with some degree of, I think not certainty but curiosity, genuine c- curiosity is that life happened fast.

Lex Fridman 2:50 Yeah, so when we say fast, th- th- this is a pretty surprising fact that maybe you can actually correct me and elaborate, but it, it seems like m- most, like 70 or 80% of the time that earth has been around there's been life on it. Like some very significant percentage. So when you say fast, like the slow part is from single cell or from bacteria to some more complicated organism it seems-

Lee Cronin 3:14 Sure.

Lex Fridman 3:14 ... like most of the time that earth has been around, it's been single cell or like very basic organisms, like a couple of billion years. But yeah, you're right, th- that's really ... I recently kind of revisited our history and saw this and I was just looking at the timeline, wait a minute, like how did life just spring up so quickly? Like really quickly? That makes me think that it really wanted to, like put another way, it's very easy for life to spring.

Lee Cronin 3:46 Yeah. I agree.

Lex Fridman 3:46 A lot.

Lee Cronin 3:46 I think it's much more inevitable and I think, um, I tried to kind of pro- not provoke but try and push chemists to think about this, because chemists are part central to this problem, right? Of understanding the origin of life on earth at least because we're made of- we're made of chemistry. But I wonder if the origin of life on a planet, also the emergence of life on planet is as, um, common as the formation of a star. And if you start framing it in that way, it allows you to then look at the universe slightly differently because, um, and we can get into this I think in quite some detail, but I think I n- to, to come back to your question, I have r- little idea of how life got started, but I know it was simple, and I know that the process of selection had to occur before the biology was established. So that selection built the framework from which life kind of grew in complexity and capability and functionality and autonomy, and I think these are all really important words that we can unpack over the next, uh, while.

Lex Fridman 4:51 Can you say all the words again? So you said selection.

Lee Cronin 4:55 Mm-hmm.

Lex Fridman 4:55 So natural selection, A- the original A/B testing.

Lee Cronin 4:59 And so, and then complexity and then, uh, the degree of autonomy and sophistication because I think that people misunderstand what life is, um, some people say that life is a cell and some people that say that life is a, um, a virus or life is a, you know, um, a- an on/off switch. I don't think it's that, life is the universe developing a memory and, um, the laws of physics and the way f- well there are no laws of physics. Physics is just memory-free stuff, right? (laughs) So there's only a finite number of ways you can arrange the fundamental particles to do things.

Lex Fridman 5:38 Life is the universe developing a memory.

Lee Cronin 5:43 Yes.

Lex Fridman 5:43 So it's like sewing a piece of art slowly and then you can look back at it, so... so there's a stickiness to life, it's like universe doing stuff-

Lee Cronin 5:58 Yep.

Lex Fridman 5:58 ... and when you say memory it's like there's a stickiness to a bunch of the stuff that's building together.

Lee Cronin 6:03 Yep.

Lex Fridman 6:04 So like you can in a, uh, stable way, like, um, trace back the complexity and that tells a coherent story.

Lee Cronin 6:13 Yeah, and I think, yeah.

Lex Fridman 6:14 Okay. That's, by the way, very poetic (laughs) and beautiful.Life is the universe developing a memory. Hmm. Okay. And then there's autonomy, you said, and complexity we'll talk about.

Lee Cronin 6:27 Mm-hmm.

Lex Fridman 6:28 But it's a really interesting idea that selection preceded biology.

Lee Cronin 6:33 Yeah. I think-

Lex Fridman 6:34 So- so what, first of all, what is chemistry? Like, does sand still count as chemistry?

Lee Cronin 6:41 Sure? I mean, as a chemist, a card-carrying chemist, if I'm allowed a card, I don't know. I don't know what I am most days

Narrator 6:46 (laughs)

Lex Fridman 6:47 What is the card made of?

Lee Cronin 6:49 (laughs)

Lex Fridman 6:49 What's the chemical composition of the card?

Lee Cronin 6:52 Yeah, so, um, what is chemistry? Well, chemistry is the thing that happens when you bring electrons together and you form bonds. So, bonds, what I say to people when they talk about life elsewhere, um, and I just say, "Where there's bonds, there's hope."

Lex Fridman 7:04 Mm.

Lee Cronin 7:04 Because bonds allow you to get heterogeneity, they allow you to record those memories. Or at least on earth. Um, you could imagine, uh, you know, a Stanislaw Lem type world where you might have life emerging, or intelligence emerging before life. That may be something to do with, on, you know, like Solaris or something.

Lex Fridman 7:22 Mm-hmm.

Lee Cronin 7:22 But, you know, to get to selection, if you can form, if atoms can combine and form bonds, those bonds, uh, uh, those atoms can bond to different elements, and those- and those molecules will have different identities and interact with each other differently, and then you can start to have some degree of causation or interaction, and then selection, and then per- and then existence. And then you- you- you go- you go up the, kind of the path of complexity. And so, at least on earth as we know it, there are c- there is a sufficient pool of available chemicals to start create, searching that combinatorial space of bonds.

Lex Fridman 8:01 So, okay, this is a really interesting question. Let's- let's lay it out. So, bonds, almost like cards. We say there's bonds, there's, uh, life, there's intelligence, there's consciousness. And what you just made me realize is, um, e- those can emerge, let's put bonds aside, uh, those can emerge in any order.

Lee Cronin 8:26 Mm-hmm.

Lex Fridman 8:27 That's- that's really brilliant. So, intelligence can come before life. It's like panpsychists believe that consciousness co-, I guess, comes before life and before intelligence. So consciousness like permeates all matter, it's some kind of fabric of reality. Okay, so the, like within this framework you can kind of arrange everything. But you need to have the bonds, um, that precedes everything else.

Lee Cronin 8:55 Mm-hmm.

Lex Fridman 8:55 Oh, and the other thing is selection.

Lee Cronin 8:57 Mm-hmm.

Lex Fridman 8:57 So like the mechanism of selection, that could, uh, precede... See, couldn't that precede bonds, too? Whatever the hell selection is.

Lee Cronin 9:05 So, I would say that there is a elegant order to it, that, uh, bonds allow selection, allows the emergence of life, allows the emergence of multicellularity, and then infom- more information processing, building state machines all the way up. However, you could imagine a situation if you had, um, I don't know, a neutron star or a sun or what, ferromagnetic loops interacting with one another, and these oscillators building state machines, and these state machines reading something out in the environment. Over time, these state machines would be able to literally record what happened in the past and sense what's going on in the- in the present and imagine the future. However, I don't think it's ever gonna be with- within a human comprehension, that type of life. Um, I wouldn't count it out because, um, you know, whenever you s- I know in science, whenever I say something's impossible, I then wake up the next day and say, "No, that's actually wrong." I mean, there are- there are some limits, of course. Um, I don't see myself traveling faster than light anytime soon. But-

Lex Fridman 10:03 Eric Weinstein says that's possible, so he will say you're wrong.

Lee Cronin 10:06 Sure, but I'm an experimentalist as well. So one of my... So I have two superpowers, uh, my stupidity, and I don't mean that as a, you know, I'm like absolutely completely witless, but I mean my ability to kind of just start again and ask the question, and then do it with an experiment. I always wanted to be a theoretician growing up, but I just didn't have the- just didn't have the intellectual capability.

Lex Fridman 10:27 Mm-hmm.

Lee Cronin 10:27 But I- I was able to think of experiments in my head I could then do in my lab or in the, you know, when I was a ch- when I was a child outside. And then those experiments in my head and then outside reinforced one another. So I think that's a very good way of kind of grounding the science, right?

Lex Fridman 10:44 Well, that's a ni- nice way to think about theoreticians is they're just people who run experiments in their head. I mean-

Lee Cronin 10:49 Yeah.

Lex Fridman 10:49 ... that's exactly what Einstein did, right?

Lee Cronin 10:51 Yeah.

Lex Fridman 10:51 And, but you're also capable of doing that in the head, in your he- inside your head and in the real world, and the connection between the two is when you first discovered your superpower of stupidity. I like it.

Lee Cronin 11:03 Yes. There you go.

Lex Fridman 11:03 Okay, what's the second superpower?

Lee Cronin 11:05 Oh.

Lex Fridman 11:05 Your accent, or

Narrator 11:06 (laughs)

Lex Fridman 11:08 ... just that...

Lee Cronin 11:08 Well, I don't know. Um, my, I like, I am genuinely curious. So my cur... So I have a, you know, like everybody, ego problems, but my curiosity's bigger than my ego. So as long as that happens-

Lex Fridman 11:18 (laughs)

Lee Cronin 11:18 ... I- I can- I can- I can cope.

Lex Fridman 11:19 Oh, that's awesome.

Lee Cronin 11:20 (laughs)

Lex Fridman 11:21 That is so powerful. You're just dropping some powerful lines. So if curiosity is bigger than ego, that's something I have to think about, 'cause e- you always struggle about the role of ego in life. And um, that's n- that's so nice to think about. Don't think about the size of ego, the absolute size of ego, think about the relative size of ego to the other- the other horses pulling at you, and if the curiosity one is bigger-

Lee Cronin 11:46 Yep.

Lex Fridman 11:46 ... then, uh, ego will, uh, do just fine and make you, uh, fun to talk to. Anyway, so those are the two superpowers. How do those connect to natural selection or in- selection and bonds and... I forgot already.

Lee Cronin 11:58 (laughs)

Lex Fridman 11:58 Life and consciousness. Uh...

Lee Cronin 12:00 So the, well going back to selection in the universe and origin of life on earth. I mean, um, selection ha- is a fo- I'm convinced that selection is a force in the universe. A, not mean- not a fundamental force, but a- but a directing... Well, it is a directing force, because existence, although, um, existence appears to be the default, um, the existence of what? Why does-Um, we can get to this later, I think, but it's amazing that- that discrete things exist and, you know, you see this cup, it's not the, you know, sexiest cup in the world, but it's pretty functional. This cup, um, the complexity of this cup isn't just in the object, it is literally the lineage of people making cups and recognizing that- seeing that in their head, making an abstraction of a cup and then making a different one so I wonder how many billions of cups have, you know, come before this one. And that's a process of selection in existence, and the only reason the cup is still used, it's quite useful, I like the handle. You know, it's convenient so I don't die. I can keep hydration. Um, and so I think we are missing something fundamental in the universe about selection, and I think what biology is, is a- is a selection amplifier and that the- this is where autonomy comes in. And actually, I think that how humanity is gonna- humans and- and autonomous robots or whatever we're going to call them in the future, will- will supercharge that even further. So selection is happening in the universe, but if you look in the asteroid belt, selection, if objects are being kicked in and out of the asteroid belt, um, those trajectories are quite complex. You don't really look at that as productive selection because it's not doing anything to improve its function. But is it? The ast- asteroid belt has existed for some time. So there is some selection going on, but the functionality is- is somewhat limited. On Earth, um, at the formation of Earth, interaction of chemicals and molecules in the environment gave selection, and then things could happen 'cause you could think about in chemistry, we have an infinite number of reactions happen, but they don't all h- all the reactions allowed to happen don't happen. Why? Because they're energy barriers. So there must be some things called catalysts out there, or there are bits of minerals that when two molecules get together on that mineral, it lowers the energy barrier for the reaction and so the reaction is- is promoted. So suddenly you get one reaction over another of series of possibilities occurring that makes a particular molecule, and this keeps happening in steps, and before you know it, these- almost these waves of discrete reactions work together, and you start to build a machinery that- that- that is run by existence. So a- as you- you go forward in time, the fact of the molecules, um, the bonds are getting... There are more bonds in a molecule, there's more function, there's more capability for this molecule to interact with other molecules, to- to redirect them. It's like a series of little, and I don't want to use this term too much, but it's almost thinking about, uh, the- it's the simplest von Neumann constructor, that's the simplest molecule that could build a more complicated molecule, to build a more complicated molecule, and before you know it, when that m- more complicated molecule can act on the causal chain that's produced itself and change it, suddenly you start to get towards some kind of autonomy, and that's where life, I think, emerges in earnest.

Lex Fridman 15:21 Every single word in- in- in the past few paragraphs, let's, uh, break those apart. So,

Lex Fridman 15:27 uh, (laughs) who's von Neumann? What's a constructor? The closing of the loop that you're talking about, uh, the- the molecule that starts becoming the- I think you said like the smallest von Neumann constructor?

Lee Cronin 15:41 Yeah.

Lex Fridman 15:41 The smallest, the minimal. So, uh, what do all those things mean and what is, uh, uh, are we supposed to imagine when we think about the smallest v- von Neumann constructor?

Lee Cronin 15:51 So, John von Neumann is a h- real hero, actually, if- not just me, but many people, I think computer science and- a- and- and physics. He was an incredible intellect, um, who probably solved a lot of the problems that we're working on today and just forgot to write them down. (laughs)

Lex Fridman 16:05 Yeah.

Lee Cronin 16:06 Um, and, um, I'm not sure if it's John von Neumann or Johnny, as I think his friends called him, but it's, um... I- I think he was Hungarian, a mathematician, came to the US and, um, basically got- was involved in the Manhattan Project in developing computation and, um, came up with all sorts of ideas, and I think it was one of the first people to come- come up with cellular automata, and- but he-

Lex Fridman 16:28 Oh, really? I didn't know this little fact. Interesting.

Lee Cronin 16:31 I think so. I think so, and I think it's-

Lex Fridman 16:32 Well, anyway, if- if he didn't come up with it, he probably did come up with it and didn't write it down.

Lee Cronin 16:37 There was a couple of people who did at the same time, and then Conway obviously took it on and then Wolfram loves CAs. There is his fabric of the universe. And what I think he imagined was that he wasn't satisfied, and th- this may be incorrect recollection, but this... So a lot of what I say is going to be kind of, you know, just way out of my, uh-

Lex Fridman 16:56 You're really... You're just part of the universe, um, creating its memory, designing...

Lee Cronin 17:02 Exactly, yeah. Yeah, rewriting history.

Lex Fridman 17:04 Rewriting history. (laughs)

Lee Cronin 17:04 Exactly. Imperfectly. So but what I mean is, I think he- he would- he liked this idea of thinking about, um, how could a Turing machine literally build itself without a Turing machine, right? It's like literally how did state machines emerge? And I think that von Neumann constructors, he was- wanted to conceive of a minimal thing, Autonoma, o- or that could build itself, and what would those rules look like in the world? And that's what a von Neumann kind of constructor looked like. Like it's a minimal hypothetical object that could build itself, self-replicate, and, um, and I'm really fascinated by that because I think that, um, although it's probably not exactly what happened, um, it's a nice model because, as chemists, if we could go back to the origin of life and think about what is a minimal machine that can get structured randomly? So like with no prime mover, with no- with no architect, and it assembles through just existence, so random stuff bumping in together and you make this first molecule. So you have molecule A, and molecule A, um, interacts with another random molecule B, and they get together and they realize by working together they can make more of themselves, but then they realize they can mutate, so they can make AB prime. So AB prime is d- different to AB, and then AB prime...... can then act back where A and B were being created, and slightly nudge that causal chain and make A, B prime more, um, evolvable or learn more. So, that's the closing the loop part.

Lex Fridman 18:40 Closing the loop part. Got it. I, it feels like the mutation part is, um, not that difficult. It feels like the difficult part is just creating a copy of yourself as step one.

Lee Cronin 18:50 Mm-hmm.

Lex Fridman 18:50 That seems, uh, um, that seems like one of the greatest inventions in the history of the universe, is the, the f- the first molecule that figured out, "Holy shit, I can create a copy of myself." How hard is that?

Lee Cronin 19:07 I think it's really, really easy. (laughs)

Lex Fridman 19:09 Okay, I did not expect that.

Lee Cronin 19:10 I think it's really, really easy. Well, let's take a step back. I think replication, replicating molecules are rare, but if you say, you know, I think I was saying on, I, I probably got into trouble on Twitter the other day, so I was trying to ... like this. Th- there's about more than 18 mills of water in there, so one mole of water, 6.022 times 10 to the 23 mo- m- molecules, that's about the number of stars in the universe, I think, of the order.

Lex Fridman 19:34 Mm-hmm.

Lee Cronin 19:34 So, there's three universe worth of a- between one and-

Lex Fridman 19:37 Oh, somebody corrected you on Twitter? (laughs)

Lee Cronin 19:39 Yeah. (laughs) I'm, as if, I, I'm always being corrected. It's a great fact. But, but there's a lot of molecules in the water.

Lex Fridman 19:43 Yeah.

Lee Cronin 19:44 And so, and so there's a lot of... So, although it's for you and me really hard to conceive of, if existence is not the default for a long period of time, because what happens is the molecules get degraded, so, so much of the possibilities in the universe are just broken back into atoms. So, you have this, um, this kind of, um, destruction of the molecules for our chemical reactions. So, you only need one or two molecules to become good at copying themselves, for them suddenly to then take resources in the pool and start to grow. And so then replication actually over time, when you have bonds, I think is much simpler and much easier. And I even found this in my lab, uh, years ago. I had, one of the reasons I started doing inorganic chemistry and making rust, making a bit of rust based on a thing called molybdenum, molybdenum oxide, is this molybdenum oxide, very simple, but when you add acid to it and some electrons, they make these molecules you just cannot possibly imagine, um, would be constructed, big gigantic wheels of 154 molybdenum atoms in a wheel, or a icosadodecahedron with 132 molybdenum atoms, all in the same pot. And I realized when I... And I just finished experiments two years ago, I've just published a couple of papers on this, that the, there actually, there is a random small molecule with 12 atoms in it that can form randomly, but it happens to template its own production, and then by chance, it templates the ring, just an accident, just like, just a absolute accident. And that ring also helps make the small 12 mer. And so you have what's called an autocatalytic set, where A, um, makes B and B helps make A, and, uh, and vice versa, and you then make this loop. So, it's a bit like, um, um, these, they all work in, in synergy to make this chain of events that grow. Um, and it doesn't take, um, a very sophisticated model to show that if you have these objects are competing and then collaborating to help one another build, they just grow out of the mess. And although they seem improbable, they are improbable, in fact impossible in one step, there's multiple steps. This is when the blind, people look at the blind watchmaker argument and you talk about how could a watch somet- some- some- spontaneously emerge. Well, it doesn't. It's a lineage of watches and cruder devices-

Lex Fridman 22:14 Mm-hmm.

Lee Cronin 22:15 ... that, that, that couple, are bootstrapped onto one another.

Lex Fridman 22:19 Right. Uh, so it's very improbable, but once you get that little discovery, like with the wheel-

Lee Cronin 22:26 Mm-hmm.

Lex Fridman 22:27 ... and, um, fire, it just gets, explodes in, because it's so successful, it explodes. It's basically selection. So, this templating mechanism that allows you to have a little, like, blueprint for yourself, how you go through different procedures as to build copies of yourself. (sighs) I don't, so I, uh, in chemistry somehow, it's possible to imagine that that kind of thing is easy to spr- spring up. In more complex organisms, it feels like a different thing and much more complicated. Like, uh-

Lee Cronin 23:01 Mm-hmm.

Lex Fridman 23:01 ... we're having, like, uh, multiple abstractions of the birds and the bees conversation here. But w- with, with human... I'm sorry, with com- complex organisms, it feels like difficult to have reproduction, uh, to, um... That's gonna get clipped out. I'm gonna be made fun of that. Um, (laughs) uh, it's diff- it's difficult to develop this idea of making copies of yourself, or no? Uh, 'cause that seems like a magical idea for life to, uh... Or, wow. That feels like very necessary for what selection is, for what evolution is. But then if selection precedes all of this, then maybe these are just like echoes of the select- the selecting mechanism at different scales.

Lee Cronin 23:47 Yeah. That's exactly it. So, selection is the default in the universe. If you want to... And what happens is that life, you know, solution that, that life has got on earth, life on earth, biology on earth, um, is unique to earth. We can talk about that. Um, and that was really hard fought for. But that was, that is the solution that works on earth. The ribosome, the fundamental machine that is responsible for every life form, you know, every cell on earth, of whatever, wherever it is in the, in the thick kingdom of life. That is an incredibly complex object, but it was evolved over time and it wasn't involved in a vacuum. And I think that once we understand that selection can, um, occur-... um, without the ribosome. But what the ribosome does, it- it's a phase transition in replication. And I think that that, and also technology, that- that is, uh, um, probably much easier to get to than we think.

Lex Fridman 24:45 Why- why do you put, uh, the ribosome as the central, um, part of living organisms on earth?

Lee Cronin 24:52 It basically is a combination of two different polymer systems. So, RNA and peptides. So the RNA world, if you like, gets transmitted and builds proteins, and the proteins are responsible for all the catalysis, or mo- the majority of the catalysis that goes on in the cell. No ribosome, no proteins, no decoding, uh, no evolution.

Lex Fridman 25:11 So the ribosome is looking at the action.

Lee Cronin 25:14 Mm-hmm.

Lex Fridman 25:14 So you don't put, like, the RNA itself as- as the critical thing, like information. You- you put action as the most important thing.

Lee Cronin 25:20 Yeah. I think the actual molecules that we have in biology right now are entirely contingent on the history of life on earth. They could... There are so many possible solutions, and this is where chemistry got itself into... Origin of life chemistry gets itself into a bit of a trap.

Lex Fridman 25:33 Yeah. Let me, uh, interrupt you there. You've tweeted. You're gonna get... I'm- I'm gonna, uh, cite your tweets like it's Shakespeare, okay?

Lee Cronin 25:40 Okay. (laughs)

Lex Fridman 25:40 It's surprising you haven't gotten canceled on Twitter yet. Um, it's your brilliance once again saves you. Um, I'm just kidding. There's- there's, uh, uh... You- you like to have a little bit of fun on Twitter.

Lex Fridman 25:51 You've tweeted that, quote, "Origin of life research (laughs) is a scam." So if this is Shakespeare, can we analyze this word? Why- why is the origin of life research a scam? Aren't you kind of doing origin of life research?

Lee Cronin 26:06 Um... Okay, it was tongue-in-cheek, but yeah. I think... And I meant it-

Lex Fridman 26:09 Yeah.

Lee Cronin 26:09 ... um, as tongue-in-cheek. Um, I am, I'm not doing or- I'm not doing the origin of life research. I'm trying to make artificial life.

Lex Fridman 26:16 Mm-hmm.

Lee Cronin 26:17 Um, and I also want to- to bound the likelihood of ma- of origin of life on earth, but more importantly to find origin of life elsewhere. But le- let me directly address the tweet. There are many, many good-

Lex Fridman 26:27 (laughs)

Lee Cronin 26:27 ... chemists out there doing origin of life research, but I want to nudge them. And I think they're brilliant. Look, th- like, there's no, there's- there's no question. The chemistry they are doing, their motivation is great. So what I meant by that tweet is saying that maybe they're making assumptions about saying if only, uh, I could make this particular type of molecule, say this RNA molecule or this pho- uh, uh, phosphodiester or this other molecule, it's gonna somehow unlock the origin of life. And I think that origin of life has been looking at this for a very long time, and whilst I- I think it's brilliant to work out how you can get to those molecules, I think that chemistry and chemists doing origin of life could be nudged into doing something even more profound. And- and so the argument I'm making, it's a bit like right now, let's say, I don't know, the first Tesla that makes its way to, I don't know, into a new country in the world. Let's say I... Let's say there's Country X that has never had a Tesla before, and they get the Tesla.

Lex Fridman 27:32 Russia.

Lee Cronin 27:32 (laughs) And they take the Tes- and what they do is they take the Tesla apart and say, "We wanna find the origin of- of cars in the universe," and say, "Okay, how did this form, and how did this form?"

Lex Fridman 27:40 Oh, I see.

Lee Cronin 27:41 And they just randomly keep making till they make the door, they make the wheel, they make the steering column, and all this stuff. And- and they say, "Well, that's the root. That's the way- that's the way cars emerged on earth." But actually, we know that there's a causal chain of cars going right back to Henry Ford and the h- horse and carriage.

Lex Fridman 27:56 Mm-hmm.

Lee Cronin 27:56 And before that maybe, you know, um, where people were using wheels. And- and I think that obsession with the identities that we see in biology right now are giving us a false sense of security about what we're looking for. And I think that origin of life chemistry is in danger of- of not making the progress that it deserves, because the chemists are doing this. There's- there's... The field is exploding right now. There's amazing people out there, young and old, doing this. And there's, deservedly so, more money going in. You know, I used to complain there's more money being spent searching for the Higgs boson, that we know exists, than the origin of life. You know, why is that? The origin... We understand the origin of life. We're gonna actually work out what life is, and we're gonna be a- bound the likelihood of finding life elsewhere in the universe. And most important for us, we are gonna know or have a good idea of what the future of humanity looks like. You know, we need to understand that although we're precious, we're not the only life forms in the universe. Well, that's my very strong impression. I have no data for that. It's just right now a belief, and I want to turn that belief into a... More than a belief by- by experimentation. But I th- coming back to the scam, the scam is if we just make this RNA, we've- we've- we've got this-

Lex Fridman 29:13 Mm-hmm.

Lee Cronin 29:13 ... you know, this, uh, this fluke event. We know how that's simple. Let's make this phosphodiester, or let's make ATP or ADP. We've got that part nailed. Let's now make this other molecule, another molecule, and how many molecules are gonna be enough? And then, the reason I say this is when you go back to Craig Venter and when he invented his life form, Sindhia, um, this pla- microbe, this- this minimal plasmid. Uh, it's a- is a myoplasma something. I don't know the name of it. But he made this wonderful, um, cell and said, "I've- I've invented life." Not quite. He facsimiled the genome from this entity and made it in the lab, or the DNA, but he didn't make the cell. He had to take an existing cell that has a causal chain going all the way back to LUCA.

Lex Fridman 30:02 Mm-hmm.

Lee Cronin 30:02 And he showed when he took out the gene, the- the genes, and put in his genes, synthesized, the cell could boot up.

Lex Fridman 30:09 Mm-hmm.

Lee Cronin 30:09 But it's remarkable that he could not make a cell from scratch. And even now today, synthetic biologists cannot make a cell from scratch because there's some contingent information embodied outside the genome in the cell, and that is just incredible. Um, so there's lots of layers to the scam. (laughs)

Lex Fridman 30:29 Well, let me then ask...... the question, how can we create life in a lab from scratch? What have been the most promising attempts at creating life in a lab from scratch? Has anyone actually been able to do it? Do you think anyone will be able to do it in the near future if they haven't already?

Lee Cronin 30:49 Um, can... Yeah. I think that, um, nobody has made life in the lab from scratch. Lots of people would argue that they have made progress. The Craig Venter, I think the synthesis of a synthetic genome, m- milestone in, in human a- achievement. Brilliant.

Lex Fridman 31:04 Yeah. Can we just walk back and s- say what, uh, would you say from your perspective, one of the world experts in exactly this area, what does it mean to create life from scratch? Where if you sit back, whether you do it or somebody else does it, it's like, "Damn. This is... we just created life."

Lee Cronin 31:24 Um, well, what I would... I can tell you what I would expect, I would like to be able to do, is to go from sand to cells in my lab and, and I-

Lex Fridman 31:37 Can you explain what sand is? You used a poor-

Lee Cronin 31:39 Yeah. Just inorganic.

Lex Fridman 31:40 ... like.

Lee Cronin 31:40 Just inorganic stuff. Like n-

Lex Fridman 31:41 Oh, okay.

Lee Cronin 31:41 Like, like basically just s- so sand is just silica, silicon oxide with some other irons in it, maybe some inorganic carbon, some carbonates. Just basically clearly dead stuff. You, you could just grind rocks into sand and...

Lex Fridman 31:55 And, and it would be what? In like in a vacuum so they could remove anything else that could possibly, uh, uh, be, uh, like a shadow of life that can exist in the chemical...

Lee Cronin 32:06 You could, you could do that. You could insist and say, "Look, I'm gonna take..." And not just inorganic. I, I want some or- I wanna cheat and have some organic but I want inorganic organic. And I'll explain the play on words in a moment. So I would like to basically put into a world, say a completely, you know, uh, a synthetic world if you like, a closed world, put some inorganic materials and just literally add some energy in some form, be it lightning or heat-

Lex Fridman 32:31 Mm-hmm.

Lee Cronin 32:32 ... UV light, and run this thing in cycles over time and let it solve the search problem. So it's a... s- I see the origin of life as a search problem in chemical space. And then I would wait, literally wait for a life form to crawl out of the test tube. That's a joke I tell my group.

Lex Fridman 32:48 Mm-hmm.

Lee Cronin 32:48 Literally wait, uh, uh, uh, for a very... uh, and don't worry, it's gonna be very feeble, it's not gonna take over the world. You know, we... there's ways of ethically containing it.

Lex Fridman 32:56 Famous last words.

Lee Cronin 32:57 (laughs) Famous... indeed. Indeed, indeed. But I, I, I...

Lex Fridman 33:01 You know this is being recorded, right? It, it'll make you... it, it will not make you look good once it crawls out of the (laughs) the lab and destroys all of human civilization. But yes, let's...

Lee Cronin 33:10 But there is very good... there is, uh, very good things you can do to prevent that.

Lex Fridman 33:13 Yes.

Lee Cronin 33:13 For instance, if you put stuff in your world which isn't earth abundant, so s- let's say we make life based on molybdenum and it escapes, it would die immediately 'cause there's not enough molybdenum in the environment. So we can put in... we can, we can do a res- we can do responsible life. Or as I fantasize with my research group on our away day that we'd go and... it's, you know, I think it's actually morally de-... we, we... if life... if we don't find... if huma- until humanity finds life in the universe, this is going on a tangent, it's our moral obligation to make origin of life bombs, identify dead planets and bomb them with our origin of life machines-

Lex Fridman 33:45 Yeah.

Lee Cronin 33:45 ... and make them alive. I think it is our moral obligation to do that. Um, I'm s- some people might argue with me about that but I think that we need l- more life in the universe.

Lex Fridman 33:54 And then we kind of forget we, we did it and then come back f- I f- and, and then...

Lee Cronin 34:00 (laughs) And say, "Where did you come from?" But coming back to the... what I'd expect. So I just say I-

Lex Fridman 34:04 "Father?"

Lee Cronin 34:05 (laughs)

Lex Fridman 34:05 "Y- are you back?" It's... I think this is once again a Rick and Morty episode.

Lee Cronin 34:09 (laughs)

Lex Fridman 34:09 It's definitely...

Lee Cronin 34:10 It's, it's actually-

Lex Fridman 34:10 It's definitely all Rick and Morty all the way down. (laughs)

Lee Cronin 34:12 So we... I imagine we have this pristine ex- um, experiment and everything is, you know, sanitized and we put in inorganic materials and we, we have cycles, with them day-night cycles, up-down, whatever, and we look for evidence of replication and evolution over time and that's what the experiment should be. Now are there people doing this in the world right now? There are m- a couple of... there's some really good groups doing this. There's some really interesting scientists doing this around the world. They're kind of perhaps too much associated with the scam so, a- and, oh, and so they're m- they're using molecules that are already... were already invented by biology so there's a bit of replication built in, um, but I still think the work they're do- is doing... they're doing is amazing. Um, but I would like people to be a bit freer and say, "Let's just basically shake a load of sand in a box and wait for life to come out." Because that's what happened on earth and so that we have to understand that. Now how would I know I've been successful? Well, because I'm not obsessing with what molecules are in life now, I, I would wager a vast quantity of money, um, I'm not very rich so it would just be a few dollars but for me it'd be a... um, the, the, the, the solution space will be different. So the, the genetic material will be not RNA. The proteins will not be what we think. They would... it would... the solutions will be just completely different. And it might be... and it will be very feeble because that's the other thing we should be able to show, um, fairly robustly that even if I did make or someone did make a new life form in a lab, it would be so poor, uh, it... that it's not gonna live out. It is... the, the fear about making a lethal life form in a lab from scratch is, um, similar to us imagining that we are gonna make the terminator at Boston Dynamics tomorrow.

Lex Fridman 36:04 Yeah.

Lee Cronin 36:04 It's simply not... you... and, and I... and the problem is we don't communicate that properly. I know you, you yourself very, uh, y- you explain this very well, you know. There is not the AI catastrophe coming.

Lex Fridman 36:15 Mm-hmm.

Lee Cronin 36:15 Um, we're very far away from that. That doesn't mean we should ignore it. Same with the origin of life catastrophe. It's not coming any time soon. We shouldn't ignore it but we shouldn't let that fear stop us from doing those experiments.

Lex Fridman 36:26 But it would... but this is a m- much, much longer discussion 'cause there's a lot of details there. I would, I would say there is potentials for catastrophic events-... to happen in much dumber ways. Within, in AI space there's a lot of ways to create, like, uh, social networks that are creating a kind of, uh, accelerated-

Lee Cronin 36:45 Mm-hmm.

Lex Fridman 36:45 ... set of events that we might not be able to control, that the- th- social network, virality in the digital space can create mass movements of ideas that can then, if times are tough, create military conflict and all those kinds of things, but that's not intel- superintelligent AI, that's an interesting at scale application of AI. And if you look at viruses, viruses are pretty dumb, uh, but at scale their application is pretty-

Lee Cronin 37:16 I agree.

Lex Fridman 37:16 ... detrimental. And so origin of life, much like all of the kind of virology, you know, um, the very contentious word of gain-of-function research in virology, sort of like research on viruses, um, messing with them genetically, that can create a lot of problems if not done well. So we have to be very cautious. So there's a kind of... whenever you're ultra cautious about stuff in AI or in, uh, virology and biology, it, uh, borders on cynicism, I would say, where it's like everything we do is going to turn out to be destructive and terrible so I'm just going to sit here and do nothing. Okay, that's a possible solution, except for the fact that somebody's going to do it. It's, uh, science and technology progresses, so we have to do it in an ethical way, in a good way, considering in a transparent way and an open way, uh, considering, um, all the possible positive trajectories that could be taken and making sure as much as possible that we walk those trajectories. So, yeah, I don't think Terminator is coming but a totally unexpected version of Terminator may be around the corner.

Lee Cronin 38:36 Yeah, might be here already. Yeah. And so, I agree with that, and so going back to the origin of life discussion, I think that in synthetic biology right now we have to be very careful about how we edit genomes and edit synthetic biology to do things. So w- that's kind of, that's where things might go wrong in the same way as, uh, you know, Twitter turning ourselves into kind of, uh, m- uh, strange scale effects.

Lex Fridman 38:59 Mm-hmm.

Lee Cronin 38:59 I would love origin of life research, or artificial life research, to get to the point where we have those worries.

Lex Fridman 39:06 Mm-hmm.

Lee Cronin 39:06 Because that's why I think we're just so far away from that, we are ju- you know, right now I think there are two really important, um, angles. There is the origin of life people, researchers who are faithfully working on this and trying to make those molecules, the scam molecules I talk about, and then there are people on the creationist side who're saying, "Look, the fact you can't make these molecules and you can't make a cell means that, um, evolution isn't true," and all this other stuff.

Lex Fridman 39:30 Gotcha. (laughs)

Lee Cronin 39:31 Yeah, and so... and I, and, and I find that really frustrating because actually the origin of life researchers are all working in good faith, right?

Lex Fridman 39:37 Yes.

Lee Cronin 39:38 And, and so what I'm trying to do is give origin of life research a little bit more of a, of a, of an open, a- an open context. And one of the things I think is important, um, I really want to make a new life form in my lifetime. I really want to prove that life is a general phenomena, a bit like gravity in the universe, because I think that's gonna be really important for humanity's, um, global psychological state, s-

Narrator 40:04 Yeah.

Lee Cronin 40:04 ... f- meaning going forward.

Lex Fridman 40:06 That's beautifully, that's beautifully put. So one, it will help us understand our- ourselves, so that's useful for science, but two, it gives us a kind of hope, if not, uh, an awe at all the huge amounts of alien civilizations that are out there. If you can build life and understand just how easy it is to build life then that's just as good, if not much better than discovering life on another planet.

Lee Cronin 40:38 Yeah.

Lex Fridman 40:38 It's... I mean, it's, it's cheaper, (laughs) it's much cheaper-

Lee Cronin 40:43 (laughs) .

Lex Fridman 40:43 ... and much easier and, uh, probably much more conclusive because once you're able to create life, like you said, it's a search problem that, uh, there's probably a lot of different ways to do it.

Lee Cronin 40:55 Yeah.

Lex Fridman 40:55 So once you create the f- or o- once you find the first solution, you probably have all the right methodology for finding all kinds of other solutions.

Lee Cronin 41:02 Yeah. And wouldn't it be great if we could find a solution? I mean, it's probably a bit late for... I mean, I worry about climate change but I'm not that worried about climate change and I think o- one day you could think about could we engineer a new type of life form that could basically... and I, I don't want to do this and I don't think we should do this necessarily but it's a good thought experiment, that would perhaps take CO2 out of the atmosphere, or a, or an intermediate life form so it's not quite alive, it's almost like a, like an add-on that we can... with a time, a time-dependent add-on you could give to, say, cyanobacteria in the ocean or to, maybe to wheat, and say, "Right, we're just gonna grow... we're gonna fix a bit more CO2 and we're gonna work out how much we need to fix to basically save the climate and, um, and we're gonna use evolutionary principles to basically get there." What worries me is that biology's had a few billion years to find a solution for CO2 fixation and it hasn't really done... it's not... the solution isn't brilliant for our needs, but biology wasn't thinking about our needs, biology was thinking about biology's needs.

Lex Fridman 42:02 (laughs)

Lee Cronin 42:03 But I think if we can do as you say, make life in the lab, then suddenly we don't need to go t- everywhere and conclusively prove it. I think we make life in the lab, we look at the extent of life in the solar system. How far did Earth life get?

Lee Cronin 42:16 Probably we were all Martians, probably life got going on Mars, the chemistry on Mars seeded Earth. That might have been a l- a legitimate way to kind of truncate the search space.

Lex Fridman 42:25 Mm-hmm.

Lee Cronin 42:25 But in the outer solar system we might have completely different life forms, uh, on Enceladus, on Europa, um, and, and Titan, and that would be a cool thing because-

Lex Fridman 42:33 Okay, wait a minute, wait a minute, wait a minute, wait a minute. (laughs) Did you just say that you think, in terms of likelihood, life started on Mar- like, uh, statistically speaking, life started on Mars and seeded Earth?

Lee Cronin 42:45 It could be possible because life was li- so Mars was habitable for the type of life that we have right now, type of chemistry, before Earth.

Lex Fridman 42:53 Mm-hmm.

Lee Cronin 42:54 So it seems to me that l- Mars got searching, doing chemistry, right?

Lex Fridman 42:58 Hmm.

Lee Cronin 42:59 And ma-

Lex Fridman 42:59 So it started way before.

Lee Cronin 43:00 Yeah, and so they would have had a few more replicators and some other stuff, and if, if those replicators got ejected from Mars and landed on Earth, and Earth was like, "I don't need-

Lex Fridman 43:09 Thanks.

Lee Cronin 43:09 ... to start again."

Lex Fridman 43:10 Right.

Lee Cronin 43:10 Oh, (laughs) thanks for that.

Lex Fridman 43:12 (laughs)

Lee Cronin 43:12 And then it just carries on. So I- I'm not going, I think there is, that we will find evidence of life on Mars, either life we put there by mistake, (laughs) contamination-

Lex Fridman 43:21 Okay.

Lee Cronin 43:21 ... or actually life, the earliest remnants of life, um, and that would be really exciting. That's a really good reason to go there. But I think it's more unlikely because of the gravitational situation in the solar system, if we find life in the outer solar system-

Lex Fridman 43:33 Titan and all that, that would be-

Lee Cronin 43:35 ... it-

Lex Fridman 43:35 ... its own thing.

Lee Cronin 43:35 Exactly.

Lex Fridman 43:36 Wow, that would be so cool if, uh, we go to Mars and we find life that looks a hell of a lot similar to Earth life.

Lee Cronin 43:43 Yeah.

Lex Fridman 43:43 And then we'll go to, uh, Titan and all those weird moons with the ices and the volcanoes and all that kind of stuff, and then we find there something that looks, I don't know, way weirder.

Lee Cronin 43:54 Yeah.

Lex Fridman 43:55 Some other, some non-RNA type of-

Lee Cronin 43:57 Or we might find-

Lex Fridman 43:58 ... situation.

Lee Cronin 43:58 ... almost life, like in a prebiotic chemical space. And I think there are four types of exoplanets we can go look for, right? Because when JWST goes up, and touch wood, it goes up and everything's fine, we'll be, when we look at a star, we'll know, statistically, most stars have planets around them. What type of planet are they? Are they gonna be dead?

Lex Fridman 44:16 Mm-hmm.

Lee Cronin 44:16 Are they gonna be just prebiotic origin of life coming? So are they gonna be technological? You know, so with intelligence on them, and will they, will they have died? So, so, you know, uh, from, you know, had life on them, but gone.

Lex Fridman 44:30 Those are the four states of-

Lee Cronin 44:31 The four, and so, and suddenly, it's a bit like I want to classify planets the way we classify stars.

Lex Fridman 44:37 Yeah.

Lee Cronin 44:37 And I think that, in terms of their, rather than having this, "Oh, we've found, we found methane, there's evidence of life. We've found oxygen, that's ev- evidence of life. We've found-

Lex Fridman 44:45 Yeah.

Lee Cronin 44:45 ... whatever ma- molecule marker," um, and start to then stop frame things a little bit more. But-

Lex Fridman 44:51 As those four states.

Lee Cronin 44:53 Yeah.

Lex Fridman 44:53 Which, by the way, you're just saying four, but there could be a f- um, before the dead, there could be other states that we humans can't even conceive of.

Lee Cronin 45:01 Yeah, yeah. Pr- just prebiotic, almost alive, you know, got the possibility to come alive. I think, um-

Lex Fridman 45:07 But there could be a post-technological, like, whatever we think of as technology, there could be a, a, a, like, pre-conscious, like, where we all meld into one super intelligent conscious sort of, some weird thing that-

Lee Cronin 45:22 Sure.

Lex Fridman 45:22 ... naturally happens over time. (laughs)

Lee Cronin 45:23 Yeah, yeah. I mean, I, I, I think that, um, all bets are off on that.

Lex Fridman 45:26 The metaverse.

Lee Cronin 45:28 Yeah, we are-

Lex Fridman 45:28 In face, (laughs) we, we join into a virtual metaverse and, and start creating, which is kind of an interesting idea, almost arbitrary, uh, number of copies of each other much more quickly to where we can mess with different ideas in mind. Like, I can create a thousand copies of Lex, uh, like every possible version of Lex-

Lee Cronin 45:48 (laughs)

Lex Fridman 45:48 ... and then just see, like, and then I just have them, like, argue with each other and, like, until, like, in the space of ideas and see who wins out. How, how could that possibly go wrong?

Lee Cronin 45:58 (laughs)

Lex Fridman 45:58 But anyway, but, uh, eh, there's a, especially in this digital space where you can start exploring with AIs mixed in, you could start engineering arbitrary intelligences. You can start playing in the space of ideas, which might move us into a world that looks very different than the biological world.

Lee Cronin 46:15 Mm-hmm.

Lex Fridman 46:15 Like, our current world, the technology is still very much tied to our biology. It's, we, we might move past that completely at some point.

Lee Cronin 46:23 Oh, definitely. We definitely will. I think-

Lex Fridman 46:25 We definit- 'cause that could be another phase then.

Lee Cronin 46:27 Sure.

Lex Fridman 46:27 Because then you-

Lee Cronin 46:28 But I did say technological, so I think, I think I agree with you.

Lex Fridman 46:30 Mm-hmm.

Lee Cronin 46:30 I think, so you can have, let's, let's get this right. So, um, a dead world, no prospect of life. Um, prebiotic world, l- life emerging. Living, and technological. And you probably w- and the dead one, you probably won't be able to tell between the dead never been alive, and the dead one maybe got some artifacts, so maybe there's five. There's probably not more than five. Um, and I think the technological one could allow, could have life on it still, but it might just have exceeded. 'Cause, uh, you know, one way that life might survive on Earth is if we can work out how to deal with the, the coming, the real climate change that comes when the sun expands. (laughs)

Lex Fridman 47:05 Hmm.

Lee Cronin 47:05 There might be a way to survive that, you know? Um, but, um, yeah. I think that we need to start thinking statistically when it comes to looking for life in the universe.

Lex Fridman 47:15 Let me ask you then, sort of, um, statistically,

Lex Fridman 47:20 how many alien civilizations are out there in those four phases that you're talking about? When you look up at the stars, and you're sipping on some wine, and, um, talking to other people with British accents about something intelligent-

Lee Cronin 47:36 (laughs)

Lex Fridman 47:36 ... intellectual, I'm sure, uh, do you think there's, uh, a lot of alien civilizations looking back at us and wondering the same?

Lee Cronin 47:45 My romantic view of the universe is really, um, taking loans from my logical self. So what I'm saying is I have no idea, I have no idea. But having said that, there is no reason to suppose that life is as hard as we first thought it was. And so if we just take Earth as a marker, and if I think that life is a much more general phenomena than just our biology, then I think the, the universe is full of life. And the Fermi, the reason for the Fermi paradox is not that, um, they're not out there, it's just that we can't interact with the other life forms because they're so different. And I'm not saying that they're necessarily like as depicted in Arrival or other, you know, um... I'm just saying that perhaps there are very few universal facts in the universe, (laughs) and that, and maybe, um...... that it's not- it's quite ha- the tech- our technologies are quite divergent and so I think that it's very hard to know how we're gonna interact with alien life.

Lex Fridman 48:51 You think there's a lot of kinds of life that's possible. I- I guess that was the intuition-

Lee Cronin 48:55 Yeah.

Lex Fridman 48:56 ...you provided that, uh, the way biology itself, but even this particular kind of biology that we have on earth, uh, is- is something that, uh, is just one sample of, uh, nearly infant number of other possible-

Lee Cronin 49:15 Mm-hmm.

Lex Fridman 49:15 ...complex autonomous self-replicating type of things that could be possible.

Lee Cronin 49:20 Yeah.

Lex Fridman 49:20 And so we're almost unable to see the alternative, uh, versions of us. Huh. I mean, um, we'd still be able to detect them, we'd still be able to interact with them, we'd still be able to- like which, uh, which exactly is lost in translation? Why can't we- why can't we see them, why can't we talk to them? 'cause I- I too have a sense- (laughs) You put it way more poetically. But it seems both statistically and, uh, sort of romantically, it feels like the universe should be teeming with life, like super intelligent life. A- and, uh, I- I just- I s- I sit there and the Fermi paradox is very- is felt very distinctly by me when I look up at the stars because it's like- it- it's, uh, the same way I feel when I'm driving through New Jersey and listening to Bruce Springsteen and feel quite sad. Uh, it's like Louis CK talks about pulling off to the side of the road and just, uh, weeping a little bit. I'm almost like wondering like, "Hey, why- why aren't you talking to us?" You know? It feels lonely. It feels lonely 'cause it feels like they're out there.

Lee Cronin 50:38 I think that there are a number of answers to that. I think the Fermi paradox is- is perhaps based on the- the assumption that there's- that if life did emerge in the universe, it would be similar to our life and there's only one solution. Um, and I think that what we've got to start to do is go out and d- look for selection, detection rather than an evolution detection, rather than life detection. Um, and I- and I think that once we start to do that, we might start to see really interesting things. Um, and we haven't been doing this for very long, um, and we are living in an expanding universe so that makes the problem a little bit harder. (laughs)

Lex Fridman 51:15 (laughs) Everybody's always leaving-

Lee Cronin 51:17 Um, but I'm- I'm-

Lex Fridman 51:18 ...distance-wise.

Lee Cronin 51:19 I'm very optimistic that we will- Well, I don't know. There are two movies that came out in a- same- within six months of one another, Ad Astra and Cosmos. Ad Astra, the very expensive blockbuster, you know, with Brad Pitt in it and, um, saying there is no life and it's all, you know, we've got a- w- life on earth has more pressures. And Cosmos, which is a UK production, which basically aliens came and visited earth one day and they were discovered in the UK, right? It was quite- (laughs) it- it's a fun film. Um, and but- I really loved those two films and I'm- I- I- and at the same time, those films- at the time those films were coming out, I was working on a paper, um, a life detection paper, and I found it was so hard to publish this paper. And it was almost as depress- I got so depressed trying to get this science out there that I felt the depression o- of, uh, the- the film in Ad Astra, like life is- there's no- no life elsewhere in the universe. And- but I- but I am incredibly optimistic that I think we will find life in the universe, firm evidence of life, and it will have to start on earth, making life on earth and surprising us. We have to surprise ourselves and make non-biological life on earth. And then people say, "Well, you- you made this life on earth, therefore it's- you- you're part of the causal chain of that." And that might be true, but if I can show how r- I- I'm able to do it with, uh, very little cheating or very little information input, just creating like a- a- a model planet, some description, and watching it- watching life emerge, then I think that we will be even to- to persuade even the hardest critic that- that- that it's- it's possible. Now with regards to the Fermi paradox, I think that we might crush that with the JWST. It's basically, if I recall correctly, the mirror is about 10 times the size of the Hubble, that we're gonna be able to do spectroscopy, um, look at colors of exoplanets, I think. Not brilliantly, but we'll be able to start to classify them and we will start to get a real fe- feel for what's going on in the universe on these exoplanets, 'cause it's only in the last few decades, I think, maybe even last decade, that we even, um, um, came to recognize that exoplanets even are common.

Lex Fridman 53:33 Mm-hmm.

Lee Cronin 53:33 And I think that that gives us a lot of optimism that life is, um, gonna be out there, but I think we have to start framing, um- th- we have to start preparing the fact that biology is only one solution. I can tell you with confidence that biology on earth does not exist anywhere else in the universe. We are absolutely unique.

Lex Fridman 53:54 Well, okay. I love the confidence, but, uh, where does the- that confidence come

Lex Fridman 54:01 from, you know, chemistry, uh, like how many options does chemistry really have?

Lee Cronin 54:07 Many. That's the point. And the thing is, this is where the origin of life scam comes in-

Lex Fridman 54:12 (laughs)

Lee Cronin 54:12 ...uh, is that people don't quite count- they don't count the numbers. So if biology, as you find on earth, is common everywhere, then there's something really weird going on, that basically written in the quantum mechanics there's some kind of, "These bonds must form over these bonds and this catalyst must form over this catalyst," when they're all quite equal.

Lex Fridman 54:29 Mm-hmm.

Lee Cronin 54:30 Life is contingent. The- the origin of life on earth was contingent upon the chemistry available at the origin of life on earth. So that means, if we want to find other life like- other earth-like worlds, we look for the same kind of rocky world. We might look in the same zone as- as- as earth and we might expect reasonably to find...... biological-like stuff going on. That would be a reasonable hypothesis, but it won't be the same, it can't be. It's like saying, "I- I don't believe in magic, that's why I- I'm sure. I just don't believe in magic. I believe in statistics and I can do experiments." And, and so I won't get the same, exactly the same sequence of events. I'll get something different. And so there is TikTok elsewhere in the universe, but it's not the same as our TikTok, right? That- that's what I mean ?

Lex Fridman 55:17 Which aspect of it is not the same?

Lee Cronin 55:20 Well, I just think it, you- you- it... The... So what is TikTok? TikTok is a- is a mi- social media where people upload videos, right? Of silly videos. So I guess there might be-

Lex Fridman 55:29 Where there's humor, there's attention, there's-

Lee Cronin 55:31 Yeah.

Lex Fridman 55:31 ... ability to process. There's ability for intelligent organisms to collaborate on ideas and find humor in ideas and play with those ideas, make them viral.

Lee Cronin 55:40 Mm-hmm.

Lex Fridman 55:41 Memes, you know. Uh, humor seems to be kind of fundamental to human experience.

Lee Cronin 55:46 And I think that, um, that's a really interesting question we can ask. Is humor a fundamental thing in the universe? I think maybe it will be, right? In terms of you think about in a game theoretic sense, humor, uh, the emergence of humor serves a- a- a role in our game engine. And so i- if selection is fundamental in the universe then so is humor (laughs) .

Lex Fridman 56:07 Well, I- I don't- I actually don't know exactly what, uh, role humor serves. Maybe it's like, uh, from a chemical perspective it's, uh, like a catalyst for, uh... I- I guess it serves several purposes. One is a catalyst for spreading ideas on the internet. That's modern humor, but humor is also a good way to deal with, uh, the difficulty of life.

Lee Cronin 56:30 (laughs)

Lex Fridman 56:30 It's a kind of valve, release valve for suffering. Like throughout human history life has been really hard and for the people that I've known in my life who've lived through some really difficult things, uh, humor is part of how they deal with that.

Lee Cronin 56:47 Yeah.

Lex Fridman 56:47 Because it's usually dark humor, but...

Lee Cronin 56:50 (laughs) .

Lex Fridman 56:50 Yeah, it's interesting. I- I don't know exactly sort of the- what- what's the more mathematically general way to formulate what the hell is humor?

Lee Cronin 56:59 (laughs) .

Lex Fridman 57:00 What humor does it serve? But I- I still... We're kind of joking here, but it's, uh, an- a counterintuitive idea to me to think that, uh, life elsewhere in the universe is very different than life on Earth. And also, like, all of- each instantiation of life is likely very different from each other.

Lee Cronin 57:26 Yeah.

Lex Fridman 57:26 Like, maybe there's a few clusters of similar like life but, uh, it's much more likely, as what you're saying... To me it's a kind of novel thought, I'm not sure what to do with it. But you're saying that there's a- it's more common to be a weird outcast in the full spectrum of life than it is to be in some usual cluster. So every instantiation of a kind of chemistry that results in complexity that's autonomous and self-replicating, however the hell you define life, that is going to be very different every time. I don't know. I... It feels like if selection is f- a fundamental kind of directed force in the universe, won't selection result in a- in a few pockets of interesting complexities? I mean, it... Yeah. (sighs) If we ran Earth over again, over and over and over, you're saying it's going to come up with... There- there's not going to be elephants every time?

Lee Cronin 58:26 Yeah, I- I don't think so. I think, uh, and I think that there will be similarities, and I think we know, we don't know enough about how selection is, um, globally works. Um, but it might be, might be that the- the elephant, um, the emergence of elephants was wired into the history of Earth in some way like the gravitational force, how evolution was going, Cambrian explosions, blah, blah, blah, the emergence of mammals. But I- I just don't know enough about c- the contingency, right? The variability. All I do know is you count the number of bits of information required to make an element. Uh, uh, sorry, an elephant, and, and, um, think about the causal chain that provide the- the lineage of eleph- elephants going all the way back to Luca, there's a huge scope for divergence.

Lex Fridman 59:10 Yeah, but just like you said with chemistry and selection, the- the things that result in self-replicating chemistry and self-replicating organisms, uh, those are extremely unlikely as you're saying. Uh, but once they're successful, they multiply. So like I- I just... It- it might be a tiny subset of all- of all things that are possible in the universe chemically speaking, it might be a very tiny subset is actually successful at creating elephants. Or- or an elephant-like cr- uh, slash human-like creatures.

Lee Cronin 59:48 Well, there's two different questions. There's the first one, if we were to reset Earth and to start again-

Lex Fridman 59:52 At the different phases. Sorry to keep interrupting.

Lee Cronin 59:55 Yeah, no. If- if we restart Earth and start again, say we could go back- back to beginning and do the experiment or have a number of Earths, um, how similar would biology be? I would say that there would be- there would be broad similarities. But um, but the emergence of mammals is not a given unless we're gonna l- you know, throw an asteroid at each planet each time and- and go try and s- and try and faithfully reproduce what happened. Then there's the other- the other thing about when you go to another la- Earth-like planet elsewhere, maybe there's a different ratio of particular elements, maybe there's, uh, the bom- the bombardment at the beginning of the planet was quicker or longer than Earth and- and- and I just don't have enough information there. What I do know is that, um, the- the complexity of the story of life on Earth gives us lots of scope for variation and I just don't think it's a reasonable mathematical assumption to think that they will... That- that- that life on Earth that happened again would be same as what we have now.

Lex Fridman 1:00:51 Okay. But you've also extended that to say that we

Lex Fridman 1:00:55 might... That as an explanation from the- for the Fermi paradox that, uh, that means we're not able to interact with them. Or that mean... Tha- that's an explanation for why we haven't at scale heard from aliens is, um...

Lee Cronin 1:01:08 ... well, right now.

Lex Fridman 1:01:09 'Cause they're different than us.

Lee Cronin 1:01:10 We've only been looking for, say, 70, 80 years. So I think that we- the reason we have not found aliens yet is that we haven't worked out what life is.

Lex Fridman 1:01:20 No, but the aliens have worked that out, surely. Uh, I mean, uh, statistically speaking, they, they must be ha- there must be a large number of aliens that are way ahead of us on this whole life question. Unless there's something about this stage of, uh, intellectual evolution that often quickly results in nuclear war and destroys itself, like the, uh, th- there, there's something in this process that eventually, I don't know, crystallizes the complexity and it stops, either dies or stops developing. But most likely, they, they already figured it out and why aren't they contacting us? Is it some, some grad student somewhere-

Lee Cronin 1:02:03 Well-

Lex Fridman 1:02:03 ... wants to study a new, a new green planet?

Lee Cronin 1:02:06 Maybe, maybe they have. I mean, maybe, um, I mean, I don't, I mean, I don't have a coherent answer to your question other than to say that may- if there are other aliens out there, like, and they're far more advanced, they might be in contact with each other (laughs) and they might also, um, we might be at a point where w- what I'm saying quite critically is it takes two to talk, right?

Lex Fridman 1:02:26 Yeah.

Lee Cronin 1:02:26 So the aliens might be there but if we are, if we don't have the ability to recognize them and talk to them, then and the aliens aren't going to want to talk to us. And I think that's in a critical point that probably, um, if, if that is a, if that's a filter, there needs to be an ability for one to communicate with the other, and we need to know w- what life is before we do that. So we haven't qualified to even join their club to have a talk.

Lex Fridman 1:02:51 Well, I think they still wanna teach us how to talk, right? But-

Lee Cronin 1:02:56 Mm-hmm.

Lex Fridman 1:02:56 ... my, my worry is that, uh, or I, I think they would wanna teach us how to talk like you do when you meet a, uh, like when you even meet, I, I was gonna say child, but that's a human species, I, I mean like ant, you want to try to communicate with them through whatever devices you can given, given what an ant is like. I just, I worry mostly about that humans are just too close-minded or don't have the right tools.

Lee Cronin 1:03:25 You know what, I'm gonna push back on this-

Lex Fridman 1:03:26 But, but-

Lee Cronin 1:03:26 ... quite significantly. I would say because we don't understand what life is and because we don't understand how life emerged in the universe, we don't understand the physics that gave rise to life yet, and we, that means our description, fundamental description, I'm way out of my pay grade, even further out there.

Lex Fridman 1:03:42 Mm-hmm.

Lee Cronin 1:03:43 But, uh, but I'll say it anyway 'cause I think it's a fun-

Lex Fridman 1:03:44 And you don't get paid much anyway, so that-

Lee Cronin 1:03:46 (laughs)

Lex Fridman 1:03:46 ... as you said earlier, so... (laughs)

Lee Cronin 1:03:48 So, uh, uh, so I would say that we, because we don't understand the universe yet, we do not understand how the universe spat out life, and we don't know what life is, and in, I think that until we understand that, it is gonna limit our ability to even, um, we don't qualify to talk to the aliens. And so I'm gonna say that the, the, they might be there but we just, I'm not gonna say that I believe in m- interdimensional aliens being present in this room.

Lex Fridman 1:04:12 Yeah, but I think you're just being self-critical, uh, like we don't qualify. I think we, I think the fact that we don't qualify qualifies us. We're interesting i- we're interesting in our innocence.

Lee Cronin 1:04:22 No, I'm saying that because we don't understand cau- causal chains and the way that information is propagated in the universe-

Lex Fridman 1:04:28 Mm-hmm.

Lee Cronin 1:04:29 ... and we don't understand what replication is yet, and we don't understand, um, how life emerged, I think that we would not recognize aliens and they, and if, if someone doesn't recognize you, um, you wouldn't go and talk to it. You don't go and talk to ants. You don't go and talk to birds. Or maybe some birds you do, right? 'Cause you can. There's, uh, just enough cognition. So I'm saying because we don't have enough cogni- our cognitive abilities are not yet where they need to be, we probably aren't, I mean, communicating with them.

Lex Fridman 1:05:00 So you don't agree with the, uh, dating strategy of playing hard to get?

Lee Cronin 1:05:03 (laughs)

Lex Fridman 1:05:03 'Cause us humans-

Lee Cronin 1:05:06 Within, within-

Lex Fridman 1:05:06 ... that seems to attract us.

Lee Cronin 1:05:07 Within a, within a species, that's fine.

Lex Fridman 1:05:09 Okay.

Lee Cronin 1:05:09 But I think we don't have the actual ab- abstraction. No, I'm, I'm, actually I think you've ins- in this talk, in this conversation, you've helped me crystallize something that I think has been troubling me for a long time with the Fermi paradox.

Lex Fridman 1:05:20 Mm-hmm.

Lee Cronin 1:05:20 I'm pretty sure that a, a reasonable avenue is to say that you would not go and talk to your cat about calculus, right? Because-

Lex Fridman 1:05:31 But I would still pet it.

Lee Cronin 1:05:32 Sure, but I'm not talking about petting a cat. It's the analogy is that the aliens are not going to talk to us because we, uh, and I'm using calculus as an analogy for abstraction.

Lex Fridman 1:05:41 Mm-hmm.

Lee Cronin 1:05:41 Because we ha- we, we lack the, um, layer, the fundamental layer-

Lex Fridman 1:05:45 Yeah.

Lee Cronin 1:05:45 ... of understanding what life is and what the universe is in our reality, that it's, it would be so counterproductive interacting with intelligent alien species, that it would cause more angst for the uni- for human race, um-

Lex Fridman 1:05:59 But they don't care. Okay, they gotta be self-interested so they'll probably, they more care about is it interesting for them. Maybe they, I mean, uh, surely there's a way to, to, to pat the, to pet the cat (laughs) in this, in this analogy because, um, even if we lack complete understanding, it's, it must be a very frustrating experience for, for other kinds of intelligences to communicate with us. Still there must be a way to interact with us-

Lee Cronin 1:06:29 Well-

Lex Fridman 1:06:30 ... s- like perturb the system in interesting ways to see what these creatures do.

Lee Cronin 1:06:35 We might actually find the answer, I mean, again, out of my pay grade, in, in, um, in a simulation of Earth, or say, let's say a simulation where we allow an intelligent AI to emerge, right? And that, and that AI, we then give it, um, the objective is to be curious, interact with other intelligence in its universe. And then we might find the, um, the parameters required for that AI to w- work with o- and I think you'll find if the, the AI will not talk to other AIs that don't share, uh, uh, the ability to abstract at the level of the AI, because it's just a cat and would you, are you gonna travel 20 light years-

Lex Fridman 1:07:14 But-

Lee Cronin 1:07:14 ... to go and pet a cat?

Lex Fridman 1:07:15 So not because of the inability to do so but because of, like, boredom? Is it, it's more interested, it will start talking to, it will spend most...... it will spend a majority of its time talking to other AI systems that can at least somewhat understand -

Lee Cronin 1:07:32 Give feedback.

Lex Fridman 1:07:32 ... it's much more fun.

Lee Cronin 1:07:33 It's a bit like, do we know that plants are conscious? Well, plants aren't conscious in the way we typically think, but we don't talk to them. They could be, right? On a-

Lex Fridman 1:07:38 Yeah, but there's a lot of people on earth who like gardening. There's always going to be a weird-

Lee Cronin 1:07:42 They're not talking, they're just gardening.

Lex Fridman 1:07:44 Okay. Well, you're not romantic enough to see gardening as a way of communication between humans and plants.

Lee Cronin 1:07:48 Oh, okay, you got me. (laughs)

Lex Fridman 1:07:50 (laughs) But there is, there is ways, there's always going to be the people who are curious. Jane Goodall, who lives with the, uh, with the chimps, right?

Lee Cronin 1:07:58 Mm-hmm.

Lex Fridman 1:07:58 There's always going to be curious, intelligent species that visit, uh, the weird ear- earth planet and, and try to interact. I mean, it's, it's, uh... Yeah, I, I, I think it's, it's a super cool idea that you're expressing. I just, uh, kinda have a sense, maybe it's a hope, that there's always going to be a desire to interact even with those that don't, can't possibly understand the depth of what you understand.

Lee Cronin 1:08:23 So, I'm with you that... Look, so I want to be as positive as you that we- w- that aliens do exist and we will f- we will interact with them. What I'm trying to do is to give you a, a reasonable hypothesis why we haven't yet.

Lex Fridman 1:08:35 Yeah.

Lee Cronin 1:08:35 And, and also something to strive for, to b- be able to do that. I mean, I, I, you know, I... There, there is the other view that, that, that, that the universe is just too big and, and life is just too rare. But I want to make, come up with an alternative explanation which I think is, uh, reasonable and not been philosophically and scientifically thought out, which is this, this... If you can't actually communicate with the object, the pers- the thing competently, you don't even know it's there-

Lex Fridman 1:09:03 Yeah.

Lee Cronin 1:09:03 ... then, then there's no point yet.

Lex Fridman 1:09:05 See, I, I disagree with that, but I'm totally aligned with your hopeful vision, which is like, we need to understand the origin of life. We... It will help us engineer life.

Lee Cronin 1:09:13 Mm-hmm.

Lex Fridman 1:09:13 It'll help us engineer intelligent life through perhaps on the computer side through simulation-

Lee Cronin 1:09:18 Mm-hmm.

Lex Fridman 1:09:18 ... and explore all the ways that life emerges, and that will allow us to... Uh, I think the fundamental reason we don't see overwhelming amounts of life is, I actually believe a- aliens... Of course, these are all just kind of, um, open-minded beliefs. Uh, it's, it's difficult to know for sure about any of this. But, I think there's a lot of alien civilizations which are actively communicating with us, and we're too dumb. We don't have the right tools-

Lee Cronin 1:09:46 That's what I'm-

Lex Fridman 1:09:47 ... to see it.

Lee Cronin 1:09:47 ... that's what I'm saying.

Lex Fridman 1:09:48 No, but you're, I, m- m- maybe I misinterpreted you, but y- y- well, I interpreted you to just say they kind of tried a few times and they're like, "Oh, god. Humans are too dumb."

Lee Cronin 1:09:57 No, no, no. Uh, what I'm saying is we... So, this goes two ways. Yeah, yeah, I agree with you. There could be in- co- information out there, but just put in such a way that we just don't understand it yet.

Lex Fridman 1:10:06 Right.

Lee Cronin 1:10:07 Uh, so sorry if I didn't make that clear. I mean, it's not just... I don't think we qua- ... I think we qualify as soon as we can decode their signal.

Lex Fridman 1:10:15 Right. So when you say qualify... Got it, got it. So you mean we're just not smart enough? The, the word qualify was throwing me off.

Lee Cronin 1:10:21 Well, they're not-

Lex Fridman 1:10:21 So we're not smart enough to do... It's like-

Lee Cronin 1:10:22 Yeah.

Lex Fridman 1:10:23 ... but the we just need to get smarter.

Lee Cronin 1:10:24 Yep.

Lex Fridman 1:10:24 But there... And there's a lot of people who believe... Let me get your opinion on this-

Lee Cronin 1:10:29 (laughs)

Lex Fridman 1:10:29 ... about UFO sightings. So,

Lex Fridman 1:10:35 sightings of weird phenomena that, uh, you know, what does UFO mean? Uh, it means it's, uh, a flying object and it's not identified, uh, clearly at the time of sighting. That's what UFO means. So it could be a physics phenomena, could be ball lightning, could be all kinds of fascinating... I was always fascinated with ball lightning as a, um, as... Like, the fact that there could be physical phenomena in this world that are observable by the human eye. Of course, all physical phenomena generally are fascinating that are, that, that really smart people can't explain. I love that. 'Cause it's like, wait a minute. Especially if you can replicate it-

Lee Cronin 1:11:18 Mm-hmm.

Lex Fridman 1:11:18 ... it's like, wait a minute. How does this happen? That's like the precursor to giant discoveries-

Lee Cronin 1:11:23 Mm-hmm.

Lex Fridman 1:11:23 ... in chemistry and biology and physics and so on. But, it sucks when those events are super rare, right? Physic- like, like ball lightning. Uh, so, so that's out there, and then, uh, of course, that phenomena could have other interpretations that don't have to do with the physics, the chemistry, the biology of earth. It could have to do with more extraterrestrial explanations that in large part, thanks to Hollywood and movies and all those kinds of things, captivates the imaginations of millions of people. Uh, but just because it's science fiction that captivates the imagination of people doesn't mean that some of those sightings, all it takes is one, one of those sightings is actually a sign that's it's extraterrestrial intelligence. That it's, um, object that's not of this-

Lee Cronin 1:12:16 Mm-hmm.

Lex Fridman 1:12:16 ... particular world. Do you think there's a chance that that's the case? What do you make, especially the pilot sightings, what do you make of those?

Lee Cronin 1:12:23 Um, (sighs) so I, I agree with you there's a chance. There's always a chance. Any good sci- scientist would have to, or observationist would have to, you know, I want to see if aliens exist, come, come to Earth. What I know about the universe is I think it's unlikely right now that there are aliens visiting us, b- um, but, but not impossible. I think the, um, releases, the dramatization that's been happening politically saying we're gonna release all this information, this, you know, classified information, um, I was kinda disappointed because it was just m- m- very poor, um, um, material. And right now, the, the c- you know, the, the ability to capture high resolution video, everybody is carrying around with them an incredible video device now, uh, a- and we haven't got more compelling data. And so that we've just seeing grainy pictures, a lot of hearsay, instrument kind of malfunctions and whatnot, and so I think on balance, I think it's extremely unlikely. But I think something really interesting is happening, um-... the, and also during the pandemic, right? We've all been locked down, we all want to have, we want to, our imaginations are, you know, running riot. And I think that the, the, I don't think that the, the information out there has convinced me there are any- anything interesting on the UFO side. But what it has made me very interested about is how humanity is opening up its mind to ponder aliens-

Lex Fridman 1:13:57 Mm-hmm.

Lee Cronin 1:13:57 ... and the, the mystery of our universe. And so, I don't want to dissuade people from having those thoughts and say, "You're stupid," and, "Look at that, it's clearly incorrect." That's not right, that's not fair. What I would say is that I lack sufficient data, replicated observations, to- to make me go, "Oh, I'm gonna take this seriously." But I'm really interested by the fact that there is this, um, this great deal of interest. And I think that it po- it drives me to maybe want to make a, make an artificial life form even more, and to help NASA and the Air Force and whoever go and look for things even more, because I think humanity wants to know what's out there. There's this yearning, isn't there?

Lex Fridman 1:14:38 Yeah. But, but I, see, I almost... Uh, depending on the day, I sometimes agree with you but, uh, w- i- with the thing you just said. But one of the disappointing things to me about the sightings, I still hold the belief that a non-zero number of them (laughs) , uh, is an indication of something very interesting. So, I don't side with the people who say everything could be explained with, like, uh, sensor artifacts kind of thing.

Lee Cronin 1:15:13 Yeah. I, I'd agree with you. I didn't say that either. I would say I just don't have enough data.

Lex Fridman 1:15:17 Right. But the thing I wanna push back on is, is the statement that everybody has a high-definition camera. One of the disappointing things to me about, like, the report that the government released, but in general, just having worked with government, having worked with, with people all over, uh, is how in- incompetent we are. Like, if you look at the pan- the response to the pandemic, how incompetent we are in the face of great challenges without great leadership, how incompetent we are in the face of the great mysteries before us with our great leadership. And I just think it's actually, the fact that there's a lot of high-definition cameras is not enough to capture the full richness of weird, of the mysterious phenomena out there, of which extraterrestrial intelligence visiting Earth could be one. I don't think we have, I don't think everybody having a s- a, a smartphone in their pocket is enough. I think that allows for TikTok videos, I don't think it allows for the capture of even interesting relatively rare human events. That's not that common. It's rare to have, be in the right moment, in the right time to be able to capture the thing.

Lee Cronin 1:16:30 I agree. I agree. Let me, let me rephrase what I think on this. I, I haven't seen enough information, I haven't really actively sought it out, I m- I must admit. But I'm, I'm with you and I love the idea of anomaly detection, in chemistry in particular, right? I want to make anomalies. Sorry, or not necessarily make anomalies. I want to understand an anomaly. Yeah. Let me give you two from chemistry, um, which are really quite interesting. Um, phlogiston, going way back, where people said, "There's this thing called phlogiston." And for ages, the alchemists got really, um, this kind of, the, this, the fire is the thing. Um, and that's one. And then we determined that phlogiston wasn't what we thought it is. Let's go to physics, the aether. The aether's a hard one because I think actually the aether might exist, and I'll tell you what I think the aether is later. Um, and it, and, and it, uh-

Lex Fridman 1:17:24 Wait, can you explain aether? Uh-

Lee Cronin 1:17:25 So as, as the vacuum, so it's the, the light traveling through the aether in the vacuum.

Lex Fridman 1:17:28 Mm-hmm.

Lee Cronin 1:17:28 There is some thing that we call the aether that, that basically mediates the, the movement of light.

Lex Fridman 1:17:33 Mm-hmm.

Lee Cronin 1:17:34 So y- and I think that, um, and then the other one is cold fusion, which is more of a ... so a few years ago, um, that, that people observed it when they did some electrochemistry when they were hi- uh, uh, splitting water into hydrogen and oxygen, that you could, got more energy out than you put in. And people got excited to, and they thought that this was a nuclear reaction. And, um, and in the end it was kind of discredited because you didn't detect neutrons and all the stuff. But I'm pretty sure ... I'm a chemist, I'm going, telling you this on your podcast, but why not? I'm pretty sure there's interesting electrochemical phenomena that's not completely bottomed out yet, that there is something there. However, we lack the technology and the experimental design. So all I'm saying, in your response about aliens, is that we d- we lack the experimental design to really capture these anomalies, and we are in-cir- encircling the planet with many more detection systems. We've got satellites everywhere. So there is, I do hope, that we are gonna discover more anomalies. Remember, the, the solar system isn't just static in space, it's moving through the universe. So there's just more and more chance. I'm not, what with Avi Loeb that, uh, uh, and he's generating all sorts of, kind of, um, o- a cult, I would say-

Lex Fridman 1:18:48 (laughs)

Lee Cronin 1:18:48 ... uh, uh, with this. But there, but I'm not against him. I think there is a finite chance if there are aliens in the universe that we're gonna happen upon them because we're moving through the universe.

Lex Fridman 1:18:56 What's the nature of th- uh, of the following that, uh, Avi Loeb has that-

Lee Cronin 1:18:59 He's kind- he's doubling down more and more and more and say there are aliens, interdimensional aliens and everything else, right? He's gone from space junk accelerating out of to interdimensional stuff in a very short space of time. (laughs)

Lex Fridman 1:19:11 I see.

Lee Cronin 1:19:11 He's obviously bored. (laughs)

Lex Fridman 1:19:13 (laughs) Yeah.

Lee Cronin 1:19:14 Or, or, or he wants to tap into the psyche and understand, and he's, and, you know, he's playfully kind of trying to interact with society and his peers to say, "Stop saying it's not possible." And which I agree with, we shouldn't do that, but we should frame it statistically in the same way we f- should frame anyth- everything as good scientists, st- statistically.

Lex Fridman 1:19:36 Yes.... good scientists recently. The idea of good scientists is, um, I take quite skeptically. I've been listening to a lot of scientists telling me about what is good, uh, wha- wha- what is good science.

Lee Cronin 1:19:52 That makes me sad because you've been interviewing, uh, what I would consider a lot of really good scientists-

Lex Fridman 1:19:56 No, that's true.

Lee Cronin 1:19:57 ... a lot of great thinkers and-

Lex Fridman 1:19:58 And, but th- that's exactly right. And most of the people I talk to are incredible human beings, but there's a humility that's required.

Lee Cronin 1:20:05 Mm-hmm.

Lex Fridman 1:20:05 Science is not, um, science cannot be dogmatism. Uh-

Lee Cronin 1:20:10 Sure, I agree. I mean-

Lex Fridman 1:20:11 And authority, like, um, a PhD does not give you authority, a lifelong pursuit of a particular task does not give you authority. You're just as lost and clueless as everybody else, but you're more curious and more stubborn.

Lee Cronin 1:20:27 Mm-hmm.

Lex Fridman 1:20:27 So that's, uh, that's a nice quality to have. But overall just, um, y- using the word science and statistics can often, uh, as, as you know, kind of, um, become a catalyst for dismissing, uh, new ideas, out of the box ideas, uh, wild ideas, all that kind of stuff.

Lee Cronin 1:20:50 Well, yes and no. I think that, so I'm, I like to, uh, some people find me extremely annoying in science