Joe Rogan Experience #2184 - Sara Imari Walker

1. 0:00 – 15:00

   (drumming music plays) Joe Rogan podcast.…

   1. JRJoe Rogan0:00

      (drumming music plays) Joe Rogan podcast. Check it out.

   2. NANarrator0:04

      The Joe Rogan Experience. Train by day, Joe Rogan podcast by night. All day. (instrumental music plays) So, uh, your subject matter is so fascinating to me. Um, so first, please explain what, uh, this idea of assembly theory.

   3. SWSara Imari Walker0:24

      Yeah. Um, assembly theory is born out of an interest in solving the origin of life and finding aliens. So, that's sort of the motivation. I think it's really important to be clear about that to start, because it introduces some kind of radical reconceptions of the way we think about fundamental physics, at least I think so. Um, but the key idea of the theory is that the universe cannot generate complexity outside of living processes, and so we have a way of formalizing what seems kind of intuitively obvious, that the universe doesn't generate complex objects for free. Um, and we do this with this idea of assembly theory, of thinking about the assembly space, which is like the space of all constructible objects, and you can talk about the complexity in that space as a minimal number of steps for making an object. And if you see, uh, objects that require a lot of steps to make them and they're in high abundance, life is the only thing that can make them.

   4. JRJoe Rogan1:16

      Wow. Um, so this includes plant life. This includes the-

   5. SWSara Imari Walker1:23

      Everything.

   6. JRJoe Rogan1:23

      ... everything.

   7. SWSara Imari Walker1:24

      Technology. Everything on your table (laughs) -

   8. JRJoe Rogan1:26

      Right.

   9. SWSara Imari Walker1:26

      ... you know, requires, uh, billions of years of evolution, evolution of intelligence, and, uh, technology to generate, so.

   10. JRJoe Rogan1:34

       When you say, "life to generate," what about, like, crystals? And what about, uh... Have you ever seen that enormous cave in Mexico where they have these insane crystal structures that are-

   11. SWSara Imari Walker1:44

       Is that the one that's, like, hot inside and, like-

   12. JRJoe Rogan1:46

       Yes.

   13. SWSara Imari Walker1:47

       Yes. I have seen that. It's gorgeous.

   14. JRJoe Rogan1:49

       Amazing.

   15. SWSara Imari Walker1:49

       I've never been there, but yeah.

   16. JRJoe Rogan1:50

       Amazing.

   17. SWSara Imari Walker1:50

       Yeah, totally.

   18. JRJoe Rogan1:51

       But it kind of looks like somebody made it, but it's just natural processes.

   19. SWSara Imari Walker1:54

       Yes. Um, so I'm actually really interested in understanding to what degree we can consider, um, minerals on our planet alive or artifacts of life.

   20. JRJoe Rogan2:04

       Mm.

   21. SWSara Imari Walker2:04

       Um, but we haven't formalized the theory entirely for minerals yet, so I think that one of the, uh, sort of key results we have so far is, um, actually quantifying a molecule's, uh, complexity boundary above which a molecule is so complex that we can say it's definitively of life, and we've experimentally verified measuring this property of assembly of molecules to say, "These are derived from life. These are, um," you know, and that there's a clear boundary. Uh, for minerals, we haven't done that yet 'cause we're still formalizing the theory and the kind of measurements we need to take, but I expect there to be a boundary that planets can make some kinds of crystal complexity, but not all of it that we see on this planet.

   22. JRJoe Rogan2:43

       So, what is, what's the conventional definition of life?

   23. SWSara Imari Walker2:49

       Yeah. So, there's a lotta debate about what definitions of life should hold, but the one that is usually cited by astrobiologists is, "Life is a self-sustaining chemical system capable of Darwinian evolution." And I've memorized it 'cause I find it so annoying. (laughs)

   24. JRJoe Rogan3:04

       (laughs)

   25. SWSara Imari Walker3:05

       So I'm like, "I got it down. I gotta know what I'm annoyed with." (laughs)

   26. JRJoe Rogan3:08

       (laughs) What, what, what annoys you about it?

   27. SWSara Imari Walker3:10

       Everything. It's like, actually-

   28. JRJoe Rogan3:11

       (laughs)

   29. SWSara Imari Walker3:11

       ... it was, it was very funny writing the book 'cause I wanted to get into the new ideas and, um, my, um, my editor was like, "You gotta explain how people think about life now." And I was like, "Okay. Well, this definition is the most annoying one. I'll just pick it apart." Um, and it's actually, like, all the words in it are annoying in some sense. So, the first one is that life is chemical. I've never really thought about chemistry being the defining feature of life. I think you have to separate out that life emerges, at least as we understand it, from a chemical soup on a planet. Right? So, it emerges in chemistry, but it doesn't mean it's a chemical phenomena. And the sort of analogy from the physicist's conception of nature I could draw there is, we don't think that gravity is a phenomena of rocks. Gravity represents some universal physics in our universe. Um, and so, uh, when we're thinking about, um, you know, planets and things, we don't think that they obey the laws of gravity because they're made of rocks. We understand that there's some property called mass that's much more abstract and applies to everything. Um, I think life's kind of the same. It emerges in chemistry, but there are some informational properties, these things about how life generates complex structures and how it does that so uniquely, um, that is universal physics that happens to emerge in chemistry. So, chemistry has to go out, um, it's not just a chemical phenomena. And I think you need to recognize that if you're gonna talk about, like, technology and artificial intelligence and, like, are they alive or not?

   30. JRJoe Rogan4:30

       Mm.
2. 15:00 – 30:00

   Hmm. …

   1. SWSara Imari Walker15:00

      to any intelligent species that emerges-

   2. JRJoe Rogan15:02

      Hmm.

   3. SWSara Imari Walker15:02

      ... on any planet.

   4. JRJoe Rogan15:03

      Why do you-

   5. SWSara Imari Walker15:03

      So I think it's really hard to say, like, what here is universal to other places versus... Yeah.

   6. JRJoe Rogan15:09

      It's certainly a big leap. Right? We have-

   7. SWSara Imari Walker15:10

      Yeah.

   8. JRJoe Rogan15:10

      ... no evidence.

   9. SWSara Imari Walker15:11

      Yeah.

   10. JRJoe Rogan15:11

       There's no evidence of people anywhere else.

   11. SWSara Imari Walker15:13

       Yeah.

   12. JRJoe Rogan15:13

       Or any other life form.

   13. SWSara Imari Walker15:14

       Yeah.

   14. JRJoe Rogan15:15

       No real evidence. There's a lot of shenanigans, there's a lot of weirdness, but there's no real evidence.

   15. SWSara Imari Walker15:19

       Yeah, there's no evidence for life on any other planet, and so the me- and the mechanism of how life even got on this planet is not known. I spent my entire career working on it. It's fucking hard problem. (laughs)

   16. JRJoe Rogan15:28

       (laughs)

   17. SWSara Imari Walker15:28

       Um, but, like, I think that's, like, the appropriate descriptor of it, it's really hard. So I think it's easy to speculate on, like, what we think life on other worlds will be like, and we tend to do it from a very anthropocentric lens where we'll say, "It will be like us." And, you know, even professional astrobiologists will do the same kind of thought experiments and they'll say, "Oh, well, the geochemistry on a planet should give rise to things like DNA and proteins, and so we should look for those in the universe." And I think that's really underestimating how large the space of possibilities actually is.

   18. JRJoe Rogan15:58

       Hmm. So when y- you're thinking about the emergence of life, is the only way to do it... I mean, it can't be the only way it has to emerge with certain temperatures, the way ours has, and water. It seems like there could-

   19. SWSara Imari Walker16:13

       Yeah.

   20. JRJoe Rogan16:14

       ... be a wide variety of possibilities that things could adapt to whatever particular unique environment that this planet provides, given a sustainable temperature and div- given enough resources that it can s- survive, that we could have... Look, like, we have jellyfish, right?

   21. SWSara Imari Walker16:29

       Yes. We have lots of weird stuff (laughs) on this planet.

   22. JRJoe Rogan16:32

       Yeah. They've been around as long as us.

   23. SWSara Imari Walker16:33

       Yeah.

   24. JRJoe Rogan16:34

       Right? Like-

   25. SWSara Imari Walker16:34

       Yeah.

   26. JRJoe Rogan16:34

       ... octopi.

   27. SWSara Imari Walker16:35

       Uh, octopi are really weird.

   28. JRJoe Rogan16:37

       Crazy.

   29. SWSara Imari Walker16:38

       Crazy.

   30. JRJoe Rogan16:38

       Crazy.
3. 30:00 – 45:00

   Yeah. …

   1. JRJoe Rogan30:00

      a cerebral cortex 40% larger than ours, the fact that they have different dialects that they-

   2. SWSara Imari Walker30:05

      Yeah.

   3. JRJoe Rogan30:05

      ... speak in different eras, different accents, different way they, ways they commu- And we don't even know what they're saying. We're, we're trying to use AI-

   4. SWSara Imari Walker30:12

      Yeah.

   5. JRJoe Rogan30:12

      ... to recognize the speech patterns.

   6. SWSara Imari Walker30:13

      No, I love this stuff about digital bioacoustics and, like, decoding languages-

   7. JRJoe Rogan30:16

      Yes.

   8. SWSara Imari Walker30:16

      ... of animals. It's like, totally-

   9. JRJoe Rogan30:18

      It might be our only way.

   10. SWSara Imari Walker30:19

       Yeah. It's, it's amaz- it's an amazing field. I think it's gonna take a while before we really, you know, realize the potential of it. But it's super exciting what people are trying to do.

   11. JRJoe Rogan30:27

       Well, they've been doing interspecies communication research forever-

   12. SWSara Imari Walker30:30

       Yeah.

   13. JRJoe Rogan30:30

       ... and they've gotten nowhere.

   14. SWSara Imari Walker30:31

       Right.

   15. JRJoe Rogan30:31

       They've gotten nowhere. Like-

   16. SWSara Imari Walker30:32

       Yeah.

   17. JRJoe Rogan30:32

       ... with, with the Leary stuff, uh-

   18. SWSara Imari Walker30:34

       Yep.

   19. JRJoe Rogan30:34

       ... or, um, not Leary. The guy who made the sensory deprivation tank. Goddammit.

   20. SWSara Imari Walker30:39

       I don't know who that is (laughs) either.

   21. JRJoe Rogan30:41

       Oh, it's locked in my head. I can't... I always know this guy's name and...

   22. NANarrator30:48

       Damian.

   23. JRJoe Rogan30:48

       What is it?

   24. NANarrator30:49

       You're typing too slow.

   25. JRJoe Rogan30:50

       Oh.

   26. NANarrator30:54

       Lilly.

   27. JRJoe Rogan30:54

       John Lilly. Thank you.

   28. NANarrator30:56

       There you go.

   29. JRJoe Rogan30:56

       Phew. God. Why does that happen? Like, that's a problem with the mind.

   30. SWSara Imari Walker30:59

       Uh, yeah, because you can't remember-
4. 45:00 – 1:00:00

   Hmm. …

   1. SWSara Imari Walker45:00

      nature of life, the origin of life transition has something to do with the emergence of systems that basically can persist, they can survive against this sort of random chemical noise, like, chemical soup. It's just a mess of things being created and destroyed, created and destroyed, and you get something that basically can reinforce its own existence enough to keep existing and then building more complex stuff.

   2. JRJoe Rogan45:21

      Hmm.

   3. SWSara Imari Walker45:21

      And that's really the origin of life transition. It's pretty simple to say it like that, but trying to build an experiment and understand the sort of chemical architecture that mediates that transition is quite hard, and that's where we're at right now. And-

   4. JRJoe Rogan45:31

      And so experiments are being done to try to create-

   5. SWSara Imari Walker45:33

      Yes. Yeah.

   6. JRJoe Rogan45:34

      How do they conduct these?

   7. SWSara Imari Walker45:35

      Um, so that's... My, my collaborator, Lee Cronin, uh, is a chemist, uh, and he's totally brilliant, and actually him and I are probably, uh, you know, I don't know, like, what we're trying to do is, is a little bit crazy (laughs) , um, to solve the origin of life. But, you know, like, I had an, uh, like, he- he's doing the experimental stuff, but, like, the, the sort of idea we had in mind is, like, I'll write a book, try to get the ideas out there, get people excited about thinking about this space, and he'll start a company that will digitize chemistry and try to raise the funds to actually do the experiments. So, he's trying to build the technology and the experiments. It's built on this platform he has for building robots that basically do the chemistry for you. And the idea being if we could build a large enough experiment, we could search that huge space of chemistry, a little bit like a circui- search alg- algorithm for chemistry, and then be able to look in chemical space and try to discover aliens.

   8. JRJoe Rogan46:27

      Whoa.

   9. SWSara Imari Walker46:28

      In an origin life experiment on Earth. And so that's what we're trying to do. Um... (laughs)

   10. JRJoe Rogan46:32

       Whoa.

   11. SWSara Imari Walker46:33

       I'm really excited. I hope it happens.

   12. JRJoe Rogan46:36

       Imagine if you guys d- if someone does something like this, maybe it's you, maybe it's someone else, someone does something like this and creates an artificial life form, and then starts manipulating that life form and evolving that life form-

   13. SWSara Imari Walker46:50

       Yes.

   14. JRJoe Rogan46:50

       ... through some-

   15. SWSara Imari Walker46:51

       That's the aim.

   16. JRJoe Rogan46:52

       ... sort of extraneous processes.

   17. SWSara Imari Walker46:53

       Yeah. So, I mean, y- there are benefits to that, right? So, so Lee's company, Chemify, is a digital chemistry company, and their stated aim is to be able to 3D print any molecule on demand, right? So, this has huge impact for the pharmaceutical industry, but, like, the real goal is to make an artificial life form in the lab. But that also has huge impact for humanity 'cause you imagine that now you have the ability to study in this other system all of these other kinds of chemistries, like what can you do for, like, antibiotic discovery, or, um, pharmaceutical drug discovery, or even psychedelic drug discovery if people like that. But, you know, like, there's, there's a- a crazy amount of new technology and new insights fundamentally to come out of that, but I also don't think that we're really gonna understand these other kind of technologies that we're building, like, when we're thinking about artificial intelligence and, like, is that alive or not, unless we solve this chemical problem of what life is because I think the chemical problem is much harder, but much more direct as far as, like, understanding the fundamental nature of life when you solve it in an experimental program.

   18. JRJoe Rogan47:52

       Biological life?

   19. SWSara Imari Walker47:53

       Biological life.

   20. JRJoe Rogan47:54

       W-

   21. SWSara Imari Walker47:54

       Chemical life.'Cause it won't, it won't be biology as we know it, right?

   22. JRJoe Rogan47:58

       Right.

   23. SWSara Imari Walker47:58

       That's the whole point.

   24. JRJoe Rogan47:59

       Right, that's the point.

   25. SWSara Imari Walker47:59

       It'll be alien biology that we evolve in the lab.

   26. JRJoe Rogan48:03

       Right.

   27. SWSara Imari Walker48:03

       And I actually think this is how we're gonna make first contact with alien life, because I think we won't recognize it unless we understand what it is.

   28. JRJoe Rogan48:09

       Wow. No, what ethical concerns would arise when you take a thing, like s- let's say, w- w- let's advance this, this whole process a few hundred years from now.

   29. SWSara Imari Walker48:19

       Mm-hmm.

   30. JRJoe Rogan48:20

       And you've created artificial life, you've created this thing that doesn't exist anywhere else, and then instead of it being subject to natural selection as a, a vehicle for it, it, its advancement, instead we just start fucking with it.
5. 1:00:00 – 1:08:36

   I know. …

   1. JRJoe Rogan1:00:00

      go visit that thing.

   2. SWSara Imari Walker1:00:01

      I know.

   3. JRJoe Rogan1:00:01

      Like, I need to find out what time it is, and then we'll go to the town center.

   4. SWSara Imari Walker1:00:02

      Well, imagine... But, I mean, this is a good thought experiment, right? Like, imagine being one of the first people to see a mechanical clock.

   5. JRJoe Rogan1:00:08

      How big was the first mechanical clock?

   6. NANarrator1:00:10

      It doesn't look small.

   7. JRJoe Rogan1:00:12

      It looks fucking huge.

   8. SWSara Imari Walker1:00:13

      Yeah. Now we have them, like, on our wrists.

   9. JRJoe Rogan1:00:14

      Is that the first one?

   10. NANarrator1:00:15

       I mean, probably.

   11. JRJoe Rogan1:00:16

       Just imagine the calculations-

   12. SWSara Imari Walker1:00:19

       Yeah.

   13. JRJoe Rogan1:00:19

       ... involved in figuring out how to make all these gears sort of click, click, click-

   14. SWSara Imari Walker1:00:24

       Yes.

   15. JRJoe Rogan1:00:24

       ... in sync.

   16. SWSara Imari Walker1:00:26

       Or even having a concept that you could keep time with that kind of regularity.

   17. JRJoe Rogan1:00:30

       Yeah.

   18. SWSara Imari Walker1:00:30

       'Cause like you're saying, our clocks before were based on, like, sand-

   19. JRJoe Rogan1:00:32

       Mm-hmm.

   20. SWSara Imari Walker1:00:33

       ... or shadows-

   21. JRJoe Rogan1:00:34

       Mm-hmm.

   22. SWSara Imari Walker1:00:34

       ... or water. Like, they were very elemental, right? And they were not incredibly precise.

   23. JRJoe Rogan1:00:40

       Right.

   24. SWSara Imari Walker1:00:41

       And, and then the sort of subsequent human knowledge that comes out of, like, timekeeping precision is things like the laws of gravitation, which we wouldn't understand. Like, you know, Newton and Galileo couldn't have done what they did in their generation unless mechanical clocks existed before they did.

   25. JRJoe Rogan1:00:54

       Right. And the tolerances are so tight that they've created things like tourbillon movements so that they're not... Uh, uh, they're, they're not affected by gravity.

   26. SWSara Imari Walker1:01:03

       Yeah.

   27. JRJoe Rogan1:01:04

       Like, these constant force gears. Have you ever seen tourbillon watches?

   28. SWSara Imari Walker1:01:07

       No.

   29. JRJoe Rogan1:01:07

       They're so structured.

   30. SWSara Imari Walker1:01:08

       I feel like I should build a watch now. This is kind of like I'm gonna get, like, this weird hobby where I'm gonna become, like, a watchmaker or something.

Episode duration: 2:45:19