Michael Levin: Biology, Life, Aliens, Evolution, Embryogenesis & Xenobots | Lex Fridman Podcast #325
p3lsYlod5OU • 2022-10-01
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Kind: captions Language: en it turns out that if you train a planarian and then cut their heads off the tail will regenerate a brand new brain that still remembers the original information I think planaria hold the answer to pretty much every deep question of life for one thing they're similar to our ancestors so they have true symmetry they have a true brain they're not like earthworms they're you know they're much more advanced life form they have lots of different internal organs but they're these little um they're about you know maybe two centimeters in in the centimeter to two in size I have a head in the tail and the first thing is plenary are Immortal so they do not age there's no such thing as an old planarian so that right there tells you that these theories of thermodynamic limitations of on lifespan are wrong it's not it's not that well over time of everything degrades no planaria can keep it going for uh probably you know how long have they've been around 400 million years right so these are the actual so the planaria in our lab are actually in physical continuity with planaria that we're here 400 million years ago the following is a conversation with Michael Levin one of the most fascinating and Brilliant biologists I've ever talked to he and his lab at Tufts University works on novel ways to understand and control complex pattern formation in biological systems Andre carpathi a world-class AI researcher is the person who first introduced me to Michael Levin's work I bring this up because these two people make me realize that biology has a lot to teach us about Ai and AI might have a lot to teach us about biology this is Alex Friedman podcast to support it please check out our sponsors in the description and now dear friends here's Michael Levin embryogenesis is the process of building the human body from a single cell I think it's one of the most incredible things that exists on Earth from a single embryo so how does this process work yeah it is it is an incredible process uh I think it's maybe the most magical process there is and I think one of the most fundamentally interesting things about it is that it shows that each of us takes the journey from so-called just physics to mind right because we all Start Life as a single quiescent unfertilized oocyte and it's basically a bag of chemicals and you look at that and you say okay this is chemistry and physics and then nine months and some years later you have an organism with high level cognition and preferences and an inner life and so on and what embryogenesis tells us is that that transformation from physics to mind is gradual it's smooth there is no special place where you know a lightning bolt says boom now you've gone from from physics to True cognition that doesn't happen and so we can see in this process that the whole mystery you know the biggest mystery of the you of the universe basically how you get mind from matter from just physics in quotes yeah so where's the magic into the thing how do we get from information encoded in DNA and make physical reality out of that information so one of the things that I think is really important if we're going to bring in DNA into this picture is to think about the fact that what DNA encodes is the hardware of Life DNA contains the instructions for the kind of micro level Hardware that every cell gets to play with so all the proteins all the signaling factors the ion channels all the cool little pieces of Hardware that cells have that's what's in the DNA the rest of it is in so-called generic laws and these are laws of mathematics these are laws of computation these are laws of um of physics of all all kinds of interesting things that are not directly in the DNA and that that process you know I think I think the reason the reason I always put just physics in quotes is because I don't think there is such a thing as just physics I think that thinking about these things in binary categories like this is physics this is true cognition this is as if it's only faking other these kinds of things I think that's what gets us in trouble I think that we really have to understand that it's a Continuum and we have to work up the scaling the laws of scaling and we can and we can certainly talk about that there's a lot of really interesting thoughts to be had there so the physics is deeply integrated with the information so the DNA doesn't exist on its own the DNA is a integrated as in some sense in response to the the laws of physics at every scale the laws of the environment it exists in yeah the environment and also the laws of the Universe I mean the thing about the thing about the the DNA is that it's um once Evolution discovers a certain kind of machine that if if the physical implementation is appropriate it's sort of uh and this is hard to talk about because we don't have a good vocabulary for this yet but it's a very kind of a platonic notion that if the machine is there it pulls down interesting uh interesting things that you do not have to evolve from scratch because the laws of physics give it to you for free so just as a really stupid example if you're trying to evolve a particular triangle you can evolve the first angle and you evolve the second angle but you don't need to evolve the third you know what it is already now why do you know that's that's a gift for free from geometry in a particular space you know what that angle has to be and if you evolve an ion Channel which is Ion channels are basically transistors right they're voltage-gated current conductances if you evolve that ION channel you immediately get to use things like truth tables you get logic functions you don't have to evolve the logic function you don't have to evolve a truth table doesn't have to be in the DNA it's you get it for free right and the fact that if you have nand Gates you can build anything you want you get that for free all you have to evolve is that that first step a first little machine that that enables you to couple to those laws and there's laws of adhesion and and many other things and this is all um that interplay between the the hardware that's set up by the genetics and the software that's paid right the physiological software that basically does all the computation and the cognition and everything else is a real interplay between the information and the DNA and the laws of physics of computation and so on so is it fair to say just like this idea that the laws of mathematics are discovered they're Laden within the fabric of the universe in that same way the laws of biology are kind of discovered yeah I think that's absolutely and it's probably not a popular view but I think that's right on the money yeah well I think that's a really deep idea then embryogenesis is the process of revealing of um embodying of manifesting these laws you're not building the laws you're just creating the capacity to reveal yes I think again not the standard view of molecular biology by any means but I think that's right on the money I'll give you a simple example you know some of our latest work with these xenobots right so what we've done is to take some skin cells off of an early frog embryo and basically ask about their plasticity if we give you a chance to sort of reboot your multicellularity in a different context what would you do because what you might assume by the thing about embryogenesis is that it's super reliable right it's very robust and that really obscures some of its most interesting features we get used to it we get used to the fact that acorns make oak trees and frog eggs make frogs and we say well what else is it going to make that's what it you know that's what it makes that's a standard story but the reality is and so and so you look at these um these skin cells you say well what do they know how to do well they know how to be a passive boring two-dimensional outer layer keeping the bacteria from getting into the embryo that's what they know how to do well it turns out that if you take these skin cells and you remove the rest of the embryo so you remove all of the rest of the cells and you say well you're by yourself now what do you want to do so what they do is they form this little um this multi-little creature that runs around the dish they have all kinds of incredible capacities they navigate through mazes they have various behaviors that they do both independently and and together they uh they have a uh but they basically they Implement Von Neumann's dream of self-replication because if you sprinkle a bunch of loose cells into the dish what they do is they run around they collect those cells into little piles they they sort of mush them together until those little piles become the next generation of xenobots so you've got this machine that builds copies of itself from loose material in its environment none of this are things that you would have expected from the Frog genome in fact there's wild type the genome was wild type there's nothing wrong with their genetics nothing has been added no Nano materials no genomic editing nothing and so what we have done there is engineer by subtraction which you've done is you've removed the other cells that normally basically bully these cells into being skin cells and you find out that what they really want to do is is to be this they want their default behaviors to be a xenobot but in Vivo in the embryo they get told to be skinned by these other cell types and so so now so now here comes this this really interesting question that you just posed when you ask where does the form of the tadpole and the Frog come from the standard answer as well it's it's it's a selection so over over millions of years right it's been shaped to to produce the specific body with that's fit for froggy environments where does the shape of the xenobot come from there's never been any zenobots there's never been selection to be a good xenobot these cells find themselves in the new environment in 48 hours they figure out how to be an entirely different uh proto-organism with new capacities like kinematic self-replication that's not how frogs or tadpoles replicate we've made it impossible for them to replicate their normal way within a couple days these guys find a new way of doing it that's not done anywhere else in the biosphere well actually let's step back and Define what are xenobots so a xenobod is uh self-assembling little proto-organism it's also a biological robot those things are not um distinct it's a member of both classes how much is a biology how much is it robot at this point most of it is biology because what we're doing is we're discovering natural uh behaviors of these uh of these of the cells and also of the cell collectives now one of the really important parts of this was that we're working together with Josh bongard's group at University of Vermont their computer scientists do Ai and they've basically been able to use an evolutionary a simulated Evolution approach to ask how can we manipulate these cells give them signals not rewire their DNA so not Hardware but experience as signals so can we remove some cells can we add some cells can we poke them in different ways to get them to do other things so in the future there's going to be you know we're now and this is this is future on published work but we're doing all sorts of interesting ways to reprogram them to new behaviors but before you can start to reprogram these things you have to understand what their innate capacities are okay so that means engineering programming you're engineering them in in the future and in some sense the the definition of a robot is something you impart engineer yeah and first versus evolve I mean um it's such a fuzzy definition anyway in some sense many of the organisms within our body are kinds of robots yes yes and I think robots is a weird line because it's we tend to see robots as the other I think there will be a time in the future when there's going to be something akin to the Civil Rights movements for robots but we'll talk about that later perhaps sure anyway um so how do you can we just Linger on it how do you build a zenobot what are we talking about here from from whence does it start and how does it become the Glorious zenobot yeah so just to take one step back one of the things that a lot of people uh get stuck on is they say well uh you know engineering requires new DNA circuits or it requires new nanomaterials you know what the thing is we are now moving from Old School engineering which use passive materials right that things like you know wood metal things like this that basically the only thing you could depend on is that they were going to keep their shape that's it they don't do anything else you it's on you as an engineer to make them do everything they're going to do and then there were active materials and now computationals this is a whole new era these are agential materials this is your you're now collaborating with your substrate because your material has an agenda these cells have you know billions of years of evolution they have goals they have preferences they're not just going to sit where you put them that's hilarious that you have to talk your material and to keep your kitchen that's it that is exactly right that is exactly right stay there it's like getting a bunch of cats or something and trying to organize the shape out of them it's funny we're on the same page here because in a paper this is this is currently um just been accepted in nature by engineering one of the figures I have is building a tower out of Legos versus dogs right yeah so think about the difference right if you build out of Legos you have full control over where it's going to go but if somebody knocks it over it's game over with the dogs you cannot just come and stack them they're not going to stay that way but the good news is that if you train them then somebody knocks it over they'll get right back up so it's all right so as an engineer what you really want to know is what can they depend on this thing to do right that's really you know a lot of people have definitions of robots as far as what they're made of or how they got here you know design versus evolve whatever I don't think any of that is useful I think I think as an engineer what you want to know is how much can I depend on this thing to do when I'm not around to micromanage it what level of uh what level of dependency can I can I give this thing how much agency does it have which then tells you what techniques do you use so do you use micromanagement like you put everything where it goes do you train it do you give it signals do you try to convince it to do things right how much you know how intelligent is your substrate and so now we're moving into this into this area where you're you're working with agential materials that's a collaboration that's not that's not old old style what's the word you're using a gentle a gentle what's that mean agency if it comes from the word agency so so basically the material has agency meaning that it has some some level of obviously not human level but some level of uh preferences goals memories ability to remember things to compute into the future meaning anticipate uh you know when you're working with cells they have all of that to some to various degrees is that empowering or limiting having material as a mind of its own literally I think it's both right so it raises difficulties because it means that it if you if you're using the old mindset which is a linear um kind of extrapolation of what's going to happen you're going to be surprised and shocked all the time because biology uh does not do what we linearly expect materials to do on the other hand it's massively liberating and so in the following way I've argued that advances in regenerative medicine require us to take advantage of this because what it means is that you can get the material to do things that you don't know how to micromanage so just as a simple example right if you if you you had a rat and uh you wanted this rat to do a circus trick put a ball in the little hoop you can do it the micromanagement way which is try to control every neuron and try to play the thing like a puppet right and maybe someday that'll be possible maybe or you can train the rat and this is why Humanity for thousands of years before we knew any Neuroscience we had no idea what's behind what's between the ears of any animal we were able to train these animals because once you recognize the level of agency of a certain system you can use appropriate techniques if you know the currency of motivation reward and Punishment you know how smart it is you know what kinds of things it likes to do you are searching a much more much smoother much nicer problem space than if you try to micromanage the thing and then regenerative medicine when you're trying to get let's say an arm to grow back or an eye to repair so birth defect or something do you really want to be controlling tens of thousands of genes at each point to try to micromanage it or do you want to find the high level modular control roles let's say build an arm here you already know how to build an arm you did it before do it again so that's I I think it's it's both it's both the difficult and it challenges us to develop new ways of engineering and it's it's hugely empowering okay so how do you do I mean maybe sticking with the metaphor of dogs and cats I presume you have to figure out the find the dogs and uh dispose of the cats um because you know it's like the old herding cats is an issue so you may be able to train dogs I suspect you will not be able to train cats or if you do you're never going to be able to trust them so is there a way to figure out which material is amenable to hurting is it in the lab work or is it in simulation right now it's largely in the lab because we are our simulations do not capture yet the most uh interesting and Powerful things about biology so the simulation what what we're pretty good at simulating are feed forward emergent types of things right so cellular automata if you have simple rules and you sort of roll those forward for every every agent or every cell in the simulation then complex things happen you know ant colony or algorithms things like that we're we're good at that and that's and that's fine the difficulty with all of that is that it's incredibly hard to reverse so this is a really hard inverse problem right if you look at a bunch of termites and they make a you know a thing with a single chimney and you say well I like it but I'd like two chimneys how do you change the rules of behavior for each termite so they make two chimneys right or or if you say hear a bunch of cells that are creating this kind of organism I I don't think that's optimal I'd like to to repair that birth defect how do you control all the all the individual low-level rules right all the protein interactions and everything else rolling it back from the anatomy that you want to the low-level Hardware rules is in general intractable it's a it's an inverse problem that's generally not soluble so um right now it's mostly in the lab because what we need to do is we need to understand how biology uses top-down controls so the idea is not not bottom-up emergence but the idea of things like gold directed uh test operate exit kinds of Loops where where it's basically an error minimization function over a new space it's not a space of gene expression but for example a space of anatomy so just as a simple example if you have you have a salamander it's got an arm you can you can amputate that arm anywhere along the length it will grow exactly what's needed and then it stops that's the most amazing thing about regeneration is that it stops it knows when to stop when does it stop it stops when a correct salamander arm has been completed so that tells you that's the right that's a that's a uh a mean Zen's kind of analysis where it has to know what the correct limb is supposed to look like right so it has a way to ascertain the current shape it has a way to measure that Delta from from what shape it's supposed to be and then we'll keep taking actions meaning Remodeling and growing and everything else until that's complete so once you know that and we've taken advantage of this in the lab to do some some really wild things with with both planaria and frog embryos and so on once you know that um you can start playing with that uh with that homeostatic cycle you can ask for example well how does it remember what the correct shape is and can we mess with that memory can we give it a false memory of what the shape should be and let the cells build something else or can we mess with the measurement apparatus right so it gives you it gives you those kinds of so so the idea is to basically appropriate a lot of the um approaches and Concepts from cognitive neuroscience and Behavioral Science into things that uh previously were taken to be dumb materials and you know you get yelled at in class if you if you for being anthropomorphic if you said well my cells want to do this and my cells want to do that and I think I think that's a that's a major mistake that leaves a ton of capabilities on the table so thinking about biologic systems is things that have memory have almost something like cognitive ability but I mean how incredible is it you know that the salamander arm is being rebuilt not with a dictator it's kind of like the cellular automata system all the individual workers are doing their own thing so where's that oh wait top down signal that doesn't control coming from like how can you find it yeah like why does it stop growing how does it know the shape how does it have memory of the shape and how does it tell everybody to be like whoa whoa slow down we're done so the first thing to to think about I think is that there are no examples anywhere of of a central dictator because in in this in this kind of science because everything is made of parts and so we we even though we we feel as a unified Central sort of intelligence and kind of point of of cognition we are a bag of neurons right we all intelligence is collective intelligence there's this this is important to kind of um and think about because a lot of people think okay there's real intelligence like me and then there's collective intelligence which is the ants and flocks of birds and you know termites and things like that and and you know and and maybe it's appropriate to think of them as a as a as an individual and maybe it's not a lot of people are skeptical about about that and so on but you've got to realize that we are not there's no such thing as this like indivisible Diamond of intelligence that's like this one Central thing that's not made of parts we are all made of parts and so if if you believe that which I think is is hard to uh to get around that that we in fact have a centralized um set of goals and preferences and we plan and we do things and so on you are already committed to the fact that a collection of cells is able to do this because we are a collection of cells there's no getting around that in our case what we do is we navigate the three-dimensional world and we have Behavior this is blowing my mind right now because we are just a collection of stuff oh yeah yeah so when I'm moving this arm I feel like I'm the central dictator of that action but there's a lot of stuff going on like every all all the cells here collaborating in some interesting way they're getting signal from the central nervous system well even the central nervous system is is misleadingly named because it isn't really Central again it's it's what it's just a bunch of cells I mean all of the right there are no you there are no singular indivisible intelligences anywhere we are all every every example that we've ever seen is is a collective of some of something it's just that we're used to it we're used to that you know we're used to okay this thing is kind of a single thing but it's really not you zoom in you know what you see you see a bunch of cells running around and so is there some unifying I mean we're just jumping around but that something that you look as the the biological signal versus the biochemical the um the chemistry the electricity maybe the life isn't that versus the cells it's the uh there's there's an orchestra playing and uh the resulting music is the dictator that's not bad um Dennis that's Dennis Nobles uh kind of view of things he has two really good books where he talks about this musical analogy right so so I think that's that's I like it um I like it is it wrong though I don't think it's no I don't think it's wrong um I don't I don't think it's wrong I think I think the important thing about it is that we have to come to grips with the fact that a true a a true proper uh cognitive intelligence can still be made of Parts those things are and in fact it has to be and I I think it's a real shame but I see this all the time when you have uh when you have a collective like this whether it be uh a group of robots or a you know a collection of cells or neurons or whatever as soon as as soon as we gain some insight into how it works right meaning that oh I see in order to take this action here's the information that got processed via this camera mechanism or whatever immediately people say oh well then that's not real cognition that's just physics I think this is this is fundamentally flawed because if you zoom into anything what are you going to see of course you're just going to see physics what else could be underneath right that's not going to be fairy dust it's going to be physics and chemistry but that doesn't take away from the magic of the fact that there are certain ways to arrange that physics and chemistry and in particular the bioelectricity which I like a lot uh to give you an emergent uh Collective with goals and preferences and memories and anticipations that do not belong to any of the subunits so I think what we're getting into here and we can talk about how how this happens during embryogenesis and so on what we're getting into is the origin of the of a self yeah with a big with a capital S so we ourselves there are many other kinds of selves and we can tell some really interesting stories about where selves come from and how they become unified yeah is this the first or at least humans tend to think that this is the the level at which the self with the capital s is first born but uh and we really don't want to see um human civilization or Earth itself as one living organism yeah that's very uncomfortable to us it is yeah but is um yeah where's the self born we have to grow up past that so what I like to do is uh I'll tell you two quick stories about that I like to roll backwards so so as opposed to so if you start and you say okay here's a paramecium and you see it um you know it's a single cell organism you see it doing various things and people will say okay I'm sure there's some chemical story to be told about how it's doing it so that's not true cognition right and people will argue about that I I like to work it backwards I said let's let's agree that you and I as as we sit here are examples of true cognition if anything is if there's anything that's true cognition we are we are examples of it now let's just roll back slowly right so you roll back to the time when you're a small child and used to doing whatever and then just sort of day by day you roll you roll back and eventually you become more or less that paramecium and then and then you sort of even below that right as an unfertilized Osa so it's no one has to my knowledge no one has come up with any convincing discreet Step At which my cognitive Powers disappear right it just doesn't the biology doesn't offer any specific step it's com it's incredibly smooth and slow and continuous and so I think this idea that it just sort of magically shows up uh at one point and then and then uh you know humans have true selves that don't exist elsewhere I think it runs against everything we know about Evolution everything we know about developmental biology these are all slow continua and the other really important story I want to tell is where embryos come from so think about this for a second amniot embryo so this is humans birds and so on mammals and birds and so on imagine a flat disc of cells so there's maybe 50 000 cells and in that so when you get an egg from a from a fertilizer let's say you buy a fertilized egg from a farm right that that egg uh will will have about 50 000 cells in um in a flat disc it looks like a little little tiny little Frisbee and in that flat disc what will happen is there'll be uh one one set of cells will uh becomes will become special and it will tell all the other cells I'm I'm going to be the head you guys don't be the head and so it'll amplify symmetry breaking amplification you get one embryo there's a there's a you know there's some neural tissue and some other stuff forms now now you say okay I had one egg and one embryo and then there you go what else could it be well the reality is and I used to I I did all of this as a grad student if you um if you take a little needle and you make a scratch in that blasted room in that in that disc such that the cells can't talk to each other for a while it heals up but for a while they can't talk to each other what will happen is that uh both regions will decide that they can be the embryo and there will be two of them and then when they heal up they become conjoint Twins and you can make two you can make three you can make lots so the question of how many selves are in there cannot be answered until it's actually played all the way through it isn't necessarily that there's just one there can be many so what you have is you have this medium this this undifferentiated I'm sure there's a there's a psychological um version of this somewhere that I don't know the proper terminology but you have this you have this list like put ocean of potentiality you have these thousands of cells and some number of individuals are going to be formed out of it usually one sometimes zero sometimes several and they they form out of these cells because a region of these cells organizes into a collective that will have goals goals that individual cells don't have for example make a limb make an eye how many eyes well exactly two so individual cells don't know what an eye is they don't know how many eyes you're supposed to have but the collective does the collective has goals and memories and anticipations that the individual cells don't and that that the establishment of that boundary with its own ability to maintain to to pursue certain goals that's the origin of of selfhood but I is that goal in there somewhere but they always destined like are they discovering that goal like where the hell did Evolution um discover this when you went from the prokaryotes to you you carry out excels and then they started making groups and when you make a certain group you make a you you make it sound that's such a tricky thing to try to understand you make it sound like this cells didn't get together and came up with a goal but the very Act of them getting together revealed the goal that was always there there was always that potential for that goal so the first thing to say is that there are way more questions here than than certainties okay so everything I'm telling you is is Cutting Edge developing you know stuff so so it's not as if any of us know the answer to this but but here's here's here's my opinion on this I think what evolution I I don't think that Evolution produces solutions to specific problems in other words specific environments like here's a frog that can live well in a froggy environment I think what evolution produces is problem-solving machines and that that will that will solve problems in different spaces so not just three-dimensional space this goes back to what we were talking about before we the the brain is a evolutionarily a late development it's a system that is able to to pursue goals in three-dimensional Space by giving commands to muscles where did that system come from that system evolved from a much more ancient evolutionarily much more ancient system where collections of cells gave instructions to for cell behaviors meaning cells move to to divide to to die to change into different cell types to navigate morphe space the space of anatomies the space of all possible anatomies and before that cells were navigating transcriptional space which is a space of all possible Gene expressions and before that metabolic space so what evolution has done I think is is is produced Hardware that is very good at navigating different spaces using a bag of tricks right which which I'm sure many of them we can steal for autonomous vehicles and Robotics and various things and what happens is that they navigate these spaces without a whole lot of commitment to what the space is in fact they don't know what the space is right we are all brains in a vat so to speak every cell does not know right every cell is some other some other cells external environment right so where does the with that border between you you and the outside world you don't really know where that is right every every collection of cell has to figure that out from scratch and the fact that Evolution requires all of these things to figure out what they are what effectors they have what sensors they have where does it make sense to draw a boundary between me and the outside world the fact that you have to build all that from scratch this autopoiesis is what defines uh the border of a self now biology uses like a um a multi a multi-scale competency architecture meaning that every level has goals so so molecular networks have goals cells have goals tissues organs colonies uh and and it's the interplay of all of those that uh that enable biology to solve problems in new ways for example and xenobots and various other things um this is you know uh it's it's exactly as you said in many ways the cells are discovering new ways of being but at the same time Evolution certainly shapes all this so so evolution is very good at this agential bioengineering right when evolution is uh discovering a new way of being an animal yet one animal or a plant or something sometimes it's by changing the hardware you know protein changing proteins protein structure and so on but much of the time it's not by changing the hardware it's by changing the signals that the cells give to each other it's doing what we as Engineers do which is try to convince the cells to do various things by using signals experiences stimuli that's what biology does it has to because it's not dealing with a blank slate every time as you know if you're a Evolution and you're trying to uh uh make make a make an organism you're not dealing with a passive material that is is fresh and you have to specify it already wants to do certain things so the easiest way to do that search to find whatever is going to be adaptive is to find the signals that are going to um convince cells to do various things right your sense is that Evolution operates both in the software and the hardware and it's just easier more efficient to operate in the software yes and I should also say I I don't think the distinction is sharp in other words I think it's a Continuum but I think we can but I think it's a meaningful distinction where you can make changes to a particular protein and now the enzymatic function is different and it metabolizes differently and whatever and that will have implications for Fitness or you can change the huge um amount of information in the genome that isn't structural at all it's it's uh it's signaling it's when and how do cells say certain things to each other and that can have massive changes as far as how it's going to solve problems I mean this idea of multi-hierarchical competence architecture which is incredible to think about so this hierarchy that Evolution builds I don't know who's responsible for this I also see the incompetence of bureaucracies of humans when they get together so how the hell does evolution build this where at every level only the best get to stick around they somehow figure out how to do their job without knowing the bigger picture and then there's like the bosses that do the bigger thing somehow or that you can now abstract away the small group of cells as a as an organ or something and then that organ does something bigger in the context of the full body or something like this how is that built is there some intuition you can kind of provide of how that's constructed that that hierarchical confidence architecture I love that confidence just the word confidence is pretty cool in this context because everybody's good at their job somehow yeah no it's really key and the other nice thing about competency is that so so my my central belief in all of this is that engineering is the right perspective on all of this stuff because it gets you away from uh subjective uh terms you know people talk about sentience and this and that those things very hard to define or people argue about them philosophically I think that engineering terms like competency like um you know pursuit of goals right all of these things are uh are empirically incredibly useful because you know it when you see it and if it helps you build right if I if I can pick the right level I say uh this thing has I believe this is X level of like con if you competency I think it's like a thermostat or I think it's like a a better thermostat or I think it's a you know a a various other kinds of you know many many different kinds of complex systems if that helps me to control and and predict and build such system then that's all there is to say there's no more philosophy to argue about so so I like competency in that way because you can quantify you could you have to in fact you have to you have to make a claim competent at what and then or if I say if I tell you it has a goal the question is what's the goal and how do you know and I say well because every time I deviated from this particular State that's what it spends energy to get back to that's the goal and we can quantify and we can be objective about it so so so the the when we're not used to thinking about this I I give a talk sometimes called why don't robots get cancer right and the reason robots don't get cancer is because generally speaking with a few exceptions are our architectures have been you've got a bunch of dumb parts and you hope that if you put them together the the the the overlying machine will have some intelligence and do something rather right but the individual Parts don't don't care they don't have an agenda biology isn't like that every level has an agenda and the final outcome is the result of cooperation and competition both within and across levels so for example during embryogenesis your tissues and organs are competing with each other and it's actually a really important part of development there's a reason they compete with each other they're not all just uh you know sort of helping each other they're also competing for for information for metabolic for limited metabolic constraints but to get back to your your other point which is you know which is which is this seems like really efficient and and good and and so on compared to some of our human efforts we also have to keep in mind that what happens here is that each level bends the option space for the level beneath so that your parts basically they don't see the the geometry so so I'm using um and I think I I take this this seriously uh terminology from from like um from like relativity right where the space is literally bent so the option space is deformed by the higher level so that the lower levels all they really have to do is go down their concentration gradient they don't have to in fact they don't they can't know what the big picture is but if you bend the space just right if they do what locally seems right they end up doing your bidding they end up doing things that are optimal in the in the higher space conversely because the components are good at getting their job done you as the higher level don't need to to try to compute all the low level controls all you're doing is bending the space you don't know or care how they're going to do it give you a super simple example in the um in the tadpole we found that okay so so tadpoles need to become frogs and to become to go from a tadpole head to a frog head you have to rearrange the face so the eyes have to move forward the Jaws have to to come out the nostrils move like everything moves it used to be thought that because all tadpoles look the same and all frogs look the same if you just remember if every piece just moves in the right direction the right amount then you get your you get your frog right so we decided to test we I had this hypothesis that I thought I thought actually the system is probably more intelligent than that so what did we do we made what we call Picasso tadpoles so these are so everything is scramble so the eyes are on the back of the head their jaws are off to the side everything is scrambled well guess what they make they make pretty normal frogs because all the different things move around in novel paths configurations until they get to the correct froggy sort of frog face configuration then they stop so so the thing about that is now imagine Evolution right so so you make some sort of mutation and it does like every mutation it does many things so so something good comes of it but also it moves your mouth off to the side right now if if if there wasn't this multi-scale companies you can see where this is going if there wasn't this multi-scale competency the organism would be dead your Fitness is zero because you can't eat and you would never get to explore the other beneficial consequences of that mutation you'd have to wait until you find some other way of doing it without moving them out that's really hard so so the fitness landscape would be incredibly rugged Evolution would take forever the reason it works one of the reasons it works so well is because you do that no worries the mouth will find its way where where it belongs right so now you get to explore so so what that means is that all these mutations that otherwise would be deleterious are now neutral because the competency of the parts make up for all kinds of things so all the noise of development all the the variability in the environment all these things the companies do the parts makes up for it so the so so that's all that's all fantastic right that's all that's all great the only other thing to remember when we compare this to human efforts is this every component has its own goals in various spaces usually with very little regard for the welfare of the other levels so so as a simple example you know um you as a as a complex system um you will go out and you will do you know Jiu Jitsu or whatever you'll have some to go rock climbing scrape a bunch of cells off your hands and then you're happy as a system right you come back and you've you've accomplished some goals and you're really happy those cells are dead they're gone right did you think about those cells not really right you had some you had some bruising out selfish SLB that's it and so and so that's the thing to remember is that um you know and we know this from from history is that is that just being a collective isn't enough because uh what the goals of that Collective will be relative to the welfare of the individual Parts is a massively open place justify the means I'm telling you Stalin was on to something no that's the danger but we can exactly that's the danger of uh for us humans we have to construct ethical systems under which we don't take seriously the full mechanism of biology and apply it to the way the world functions which is which is an interesting line we've drawn the world that built us is the one we reject in some sense when we construct human societies the idea that this country was founded on that all men are created equal that's such a fascinating idea it's like uh you're fighting against nature and you're saying well there's something bigger here than um yeah a hierarchical competency architecture yeah uh but there's so many interesting things you said so from an algorithmic perspective the act of bending the option space that's really that's really profound because if you look at the way AI systems are built today there's a big system like I said with robots and as a goal and he gets better and better at optimizing that goal at accomplishing that goal but if biology built a hierarchical system where everything is doing computation and everything is accomplishing the goal not only that it's kind of dumb you know with the uh with the limited with the bent option space it's just doing the thing that's the easiest thing for it in some sense and somehow that allows you to have um Turtles on top of turtles literally dump systems on top of dump systems that as a whole create something incredibly smart yeah I mean every system is has some degree of intelligence in its own problem domain so so cells will have problems they're trying to solve in physiological space and transcriptional space and then I could give you some some cool examples of that but the collective is trying to solve problems in anatomical space right and forming a you know a creature and growing your blood vessels and so on and then the collect the the the the whole body is solving yet other problems they may be in Social space and linguistic space in three-dimensional space and and who knows you know the group might be solving problems and and um you know I don't know some sort of financial space or something so one of the major differences with with most um uh with most AIS today is is a the the kind of flatness of the architecture but also of the fact that they're constructed from outside their their borders and their you know so so if you're so to a large extent and of course there are counter examples now but but to a large extent our technology has been such that you create a machine or a robot it knows what its sensors are it knows what its effectors are it knows the boundary between it and the outside world all this is given from the outside biology constructs this from scratch now the best example of this that that originally uh in in robotics was actually Josh bongard's work in 2006 where he made these these robots that did not know their shape to start with so like a baby these are floundered around they made some hypotheses well I did this and I moved in this way well maybe I'm a whatever maybe I have wheels or maybe I have six legs or whatever right and they would make a model and eventually they would crawl around so that's I mean that's really good that's part of the autopoiesis but we can go a step further and some people are doing this and then we're sort of working on some of this too is this idea that let's even go back further you don't even know what sensors you have you don't know where you end and the outside world begins all you have is is certain things like active inference meaning you're trying to minimize surprise right you have some metabolic constraints you don't have all the energy you need you don't have all the time in the world to to think about everything you want to think about so that means that you can't afford to be a micro um reductionist you know all this data coming in you have to coarse grain it and say I'm going to take all this stuff and I'm going to call that a cat I'm gonna take all this I'm going to call that the edge of the table I don't want to follow off of and I don't want to know anything about the microstates what I want to know is what is the optimal way to cut up my world and by the way this thing over here that's me and the reason that's me is because I have more control over this than I have over any of this other stuff and so now you can begin to write so that's self-construction that that figuring out making models of the outside world and then turning that inwards and starting to make a model of yourself right which immediately starts to get into issues of agency and control because in order to if if you are under metabolic constraints meaning you don't have the energy right that all the energy in the world you have to be efficient that immediately forces you to start telling stories about course grained agents that do things right you don't have the energy to like laplaces demon you know calculate every every possible uh State that's going to happen you have to you have to coarse grain and you have to say that is the kind of creature that does things either things that I avoid or things that I will go towards that's a mate or food or whatever it's going to be and so right at the base of uh simple very simple organisms starting to make models of Agents doing things that is the origin of uh models of of Free Will basically right because you see the world around you as having agency and then you turn that on yourself and you say wait I have agency too I can I do things right and and then you make decisions about what you're going to do so all of this one one model is to view all of those kinds of things as being driven by that early need to determine what you are and to do so and to then take actions in the most energetically efficient space possible right so free will emerges when you try to simplify tell a nice narrative about your environment I think that's very possible yeah do you think free was an illusion so so you're kind of implying that it's a useful hack well I'll say two things the first thing is I think I think it's very plausible to say that a
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