Sergey Levine, one of the world’s top robotics researchers and co-founder of Physical Intelligence, thinks we’re on the cusp of a “self-improvement flywheel” for general-purpose robots. His median estimate for when robots will be able to run households entirely autonomously? 2030.
If Sergey’s right, the world 5 years from now will be an insanely different place than it is today. This conversation focuses on understanding how we get there: we dive into foundation models for robotics, and how we scale both the data and the hardware necessary to enable a full-blown robotics explosion.
Watch on YouTube; listen on Apple Podcasts or Spotify.
Sponsors
Labelbox provides high-quality robotics training data across a wide range of platforms and tasks. From simple object handling to complex workflows, Labelbox can get you the data you need to scale your robotics research. Learn more at labelbox.com/dwarkesh
Hudson River Trading uses cutting-edge ML and terabytes of historical market data to predict future prices. I got to try my hand at this fascinating prediction problem with help from one of HRT’s senior researchers. If you’re curious about how it all works, go to hudson-trading.com/dwarkesh
Gemini 2.5 Flash Image (aka nano banana) isn’t just for generating fun images — it’s also a powerful tool for restoring old photos and digitizing documents. Test it yourself in the Gemini App or in Google’s AI Studio: ai.studio/banana
To sponsor a future episode, visit dwarkesh.com/advertise.
Timestamps
(00:00:00) – Timeline to widely deployed autonomous robots
(00:22:12) – Why robotics will scale faster than self-driving cars
(00:32:15) – How vision-language-action models work
(00:50:26) – Changes needed for brainlike efficiency in robots
(01:02:48) – Learning from simulation
(01:14:08) – How much will robots speed up AI buildouts?
(01:22:54) – If hardware’s the bottleneck, does China win by default?
Transcript
00:00:00 – Timeline to widely deployed autonomous robots
Dwarkesh Patel 00:00:00
Today I'm chatting with Sergey Levine, who is a co-founder of Physical Intelligence, which is a robotics foundation model company, and also a professor at UC Berkeley and just generally one of the world's leading researchers in robotics, RL, and AI. Sergey, thank you for coming on the podcast.
Sergey Levine 00:00:16
Thank you, and thank you for the kind introduction.
Dwarkesh Patel 00:00:18
Let's talk about robotics. Before I pepper you with questions, I'm wondering if you can give the audience a summary of where Physical Intelligence is at right now. You guys started a year ago. What does the progress look like? What are you guys working on?
Sergey Levine 00:00:31
Physical Intelligence aims to build robotic foundation models. That basically means general-purpose models that could in principle control any robot to perform any task. We care about this because we see this as a very fundamental aspect of the AI problem. The robot is essentially encompassing all AI technology. If you can get a robot that's truly general, then you can do, hopefully, a large chunk of what people can do.
Where we're at right now is that we've kind of gotten to the point where we've built out a lot of the basics. Those basics actually are pretty cool. They work pretty well. We can get a robot that will fold laundry and that will go into a new home and try to clean up the kitchen. But in my mind, what we're doing at Physical Intelligence right now is really the very, very early beginning. It's just putting in place the basic building blocks, on top of which we can then tackle all these really tough problems.
Dwarkesh Patel 00:01:24
What's a year-by-year vision? One year in, I got a chance to watch some of the robots, they can do pretty dexterous tasks like folding a box using grippers. It's pretty hard to fold the box even with my hands.
If you had to go year by year until we get to the full robotics explosion, what is happening every single year? What is the thing that needs to be unlocked, et cetera?
Sergey Levine 00:01:47
There are a few things that we need to get right. Dexterity obviously is one of them. In the beginning we really want to make sure that we understand whether the methods that we're developing have the ability to tackle the kind of intricate tasks that people can do. As you mentioned, folding a box, folding different articles of laundry, cleaning up a table, making a coffee, that sort of thing. That's good, that works. The results we've been able to show are pretty cool, but the end goal of this is not to fold a nice T-shirt. The end goal is to just confirm our initial hypothesis that the basics are solid.
From there, there are a number of really major challenges. Sometimes when results get abstracted to the level of a three-minute video, someone can look at this video and it's like, "Oh, that's cool. That's what they're doing." But it's not. It's a very simple and basic version of what I think is to come. What you really want from a robot is not to tell it like, "Hey, please fold my T-shirt." What you want from a robot is to tell it like, "Hey, robot, you're now doing all sorts of home tasks for me. I like to have dinner made at 6:00 p.m. I wake up and go to work at 7:00 a.m. I like to do my laundry on Saturday, so make sure that it's ready. This and this and this. By the way, check in with me every Monday to see what I want you to pick up when you do the shopping.”
That's the prompt. Then the robot should go and do this for six months, a year. That's the duration of the task. Ultimately if this stuff is successful, it should be a lot bigger. It should have that ability to learn continuously. It should have the understanding of the physical world, the common sense, the ability to go in and pull in more information if it needs it. Let’s say I ask it, "Hey, tonight, can you make me this type of salad?" It should figure out what that entails, look it up, go and buy the ingredients. There's a lot that goes into this.
It requires common sense. It requires understanding that there are certain edge cases that you need to handle intelligently, cases where you need to think harder. It requires the ability to improve continuously. It requires understanding safety, being reliable at the right time, being able to fix your mistakes when you do make those mistakes. There's a lot more that goes into this. But the principles there are: you need to leverage prior knowledge and you need to have the right representations.
Dwarkesh Patel 00:04:05
This grand vision, what year? If you had to give an estimate. 25 percentile, 50, 75?
Sergey Levine 00:04:12
I think it's something where it's not going to be a case where we develop everything in the laboratory and then it's done and then come 2030-something, you get a robot in a box. Again, it'll be the same as what we've seen with AI assistants. Once we reach some basic level of competence where the robot is delivering something useful, it'll go out there in the world. The cool thing is that once it's out there in the world, they can collect experience and leverage that experience to get better. To me, what I tend to think about in terms of timelines is not the date when it will be done, but the date when the flywheel starts basically.
Dwarkesh Patel 00:04:48
When does the flywheel start?
Sergey Levine 00:04:50
That could be very soon. There's some decisions to be made. The trade-off there is that the more narrowly you scope the thing, the earlier you can get it out into the real world. But this is something we're already exploring. We're already trying to figure out what are the real things this thing can do that could allow us to start spinning the flywheel. But in terms of stuff that you would actually care about, that you would want to see… I don't know but single-digit years is very realistic. I'm really hoping it'll be more like one or two before something is actually out there, but it's hard to say.
Dwarkesh Patel 00:05:22
Something being out there means what? What is out there?
Sergey Levine 00:05:25
It means that there is a robot that does a thing that you actually care about, that you want done. It does so competently enough to actually do it for real, for real people that want it done.
Dwarkesh Patel 00:05:36
We already have LLMs which are broadly deployed. That hasn't resulted in some sort of flywheel, at least not some obvious flywheel for the model companies where now Claude is learning how to do every single job in the economy or GPT's learning how to do every single job in the economy. So, why doesn’t that flywheel work for LLMs?
Sergey Levine 00:05:55
Well, I think it's actually very close to working and I am 100% certain that many organizations are working on exactly this. In fact, arguably there is already a flywheel. It’s not an automated flywheel but a human-in-the-loop flywheel. Everybody who's deploying an LLM is of course going to look at what it's doing and it's going to use that to then modify its behavior.
It's complex because it comes back to this question of representations and figuring out the right way to derive supervision signals and ground those supervision signals in the behavior of the system so that it improves on what you want. I don't think that's a profoundly impossible problem. It's just something where the details get pretty gnarly and challenges with algorithms and stability become pretty complex. It's something that's taken a while for the community collectively to get their hands on.
Dwarkesh Patel 00:06:49
Do you think it'll be easier for robotics? Or do you think that with these kinds of techniques to label data that you collect out in the world and use it as a reward, the whole wave will rise and robotics will rise as well? Or is there some reason robotics will benefit more from this?
Sergey Levine 00:07:08
I don't think there's a profound reason why robotics is that different. There are a few small differences that make things a little bit more manageable. Especially if you have a robot that's doing something in cooperation with people, whether it's a person that's supervising it or directing it, there are very natural sources of supervision. There's a big incentive for the person to provide the assistance that will make things succeed. There are a lot of dynamics where you can make mistakes and recover from those mistakes and then reflect back on what happened and avoid that mistake in the future.
When you're doing physical things in the real world, that stuff just happens more often than it does if you're an AI assistant answering a question. If you answer a question and just answer it wrong, it's not like you can just go back and tweak a few things. The person you told the answer to might not even know that it's wrong. Whereas if you're folding the T-shirt and you messed up a little bit, it's pretty obvious. You can reflect on that, figure out what happened, and do it better next time.
Dwarkesh Patel 00:08:00
Okay, in one year we have robots which are doing some useful things. Maybe if you have some relatively simple loopy process, they can do it for you, like keep folding thousands of boxes or something.
But then there's some flywheel… and there's some machine which will just run my house for me as well as a human housekeeper would. What is the gap between this thing which will be deployed in a year that starts the flywheel and this thing which is like a fully autonomous housekeeper?
Sergey Levine 00:08:33
It's actually not that different from what we've seen with LLMs in some ways. It's a matter of scope. Think about coding assistants. Initially the best tools for coding, they could do a little bit of completion. You give them a function signature and they'll try their best to type out the whole function and they'll maybe get half of it right. As that stuff progresses, then you're willing to give these things a lot more agency.
The very best coding assistance now—if you're doing something relatively formulaic, maybe it can put together most of a PR for you for something fairly accessible. It'll be the same thing. We'll see an increase in the scope that we're willing to give to the robots as they get better and better. Initially the scope might be a particular thing you do. You're making the coffee or something. As they get more capable, as their ability to have common sense and a broader repertoire of tasks increases, then we'll give them greater scope. Now you're running the whole coffee shop.
Dwarkesh Patel 00:09:30
I get that there's a spectrum. I get that there won't be a specific moment that feels like we've achieved it but if you had to give a year for your median estimate of when that happens?
Sergey Levine 00:09:39
My sense there too is that this is probably a single-digit thing rather than a double-digit thing. The reason it's hard to really pin down is because, as with all research, it does depend on figuring out a few question marks. My answer in terms of the nature of those question marks is that I don't think these are things that require profoundly, deeply different ideas but it does require the right synthesis of the kinds of things that we already know. Sometimes synthesis, to be clear, is just as difficult as coming up with profoundly new stuff.
It's intellectually a very deep and profound problem. Figuring that out is going to be very exciting. But I think we kind of know roughly the puzzle pieces and it's something that we need to work on. If we work on it and we're a bit lucky and everything kind of goes as planned, single-digit is reasonable.
Dwarkesh Patel 00:10:33
I'm just going to do binary search until I get a year. It's less than 10 years, so more than five years, your median estimate? I know there's a range.
Sergey Levine 00:10:41
I think five is a good median.
Dwarkesh Patel 00:10:43
Okay, five years. If you can fully autonomously run a house, then you can fully autonomously do most blue-collar work. Your estimate is that in five years it should be able to do most blue-collar work in the economy.
Sergey Levine 00:10:59
There's a nuance here. It becomes more obvious if we consider the analogy to coding assistants. It's not like the nature of coding assistants today is that there's a switch that flips and instead of writing software, suddenly all software engineers get fired and everyone's using LLMs for everything. It actually makes a lot of sense that the biggest gain in productivity comes from experts, which is software engineers, whose productivity is now augmented by these really powerful tools.
Dwarkesh Patel 00:11:34
Separate from the question of whether people will get fired or not, a different question is, what will the economic impact be in five years? The reason I'm curious about this is because with LLMs, the relationship between the revenues for these models to their seeming capability has been sort of mysterious. You have something which feels like AGI. You can have a conversation where it really passes the Turing test. It really feels like it can do all this knowledge work. It's obviously doing a bunch of coding, et cetera. But the revenues from these AI companies are cumulatively on the order of $20-30 billion per year and that's much less than all knowledge work, which is $30-40 trillion.
In five years are we in a similar situation to what LLMs are in now, or is it more like we have robots deployed everywhere and they're actually doing a whole bunch of real work, et cetera?
Sergey Levine 00:12:28
It's a very subtle question. What it probably will come down to is this question of scope. The reason that LLMs aren't doing all software engineering is because they're good within a certain scope, but there's limits to that. Those limits are increasing, to be clear, every year. I think that there's no reason that we wouldn't see the same kind of thing with robots.
The scope will have to start out small because there will be certain things that these systems can do very well and certain other things where more human oversight is really important. The scope will grow. What that will translate into is increased productivity. Some of that productivity will come from the robots themselves being valuable. Some of it will come from the people using the robots are now more productive in their work.
Dwarkesh Patel 00:13:15
But there's so many things which increase productivity. Like wearing gloves increases productivity or I don't know. You want to understand something which increases productivity a hundredfold versus something which has a small increase. Robots already increase productivity for workers.
Where LLMs are right now in terms of the share of knowledge work they can do, is I guess like 1/1000th of the knowledge work that happens in the economy, at least in terms of revenue. Are you saying that fraction will be possible for robots, but for physical work, in five years?
Sergey Levine 00:13:56
That's a very hard question to answer. I'm probably not prepared to tell you what percentage of all labor work can be done by robots, because I don't think right now, off the cuff, I have a sufficient understanding of what's involved in that big of a cross-section of all physical labor. What I can tell you is this. It's much easier to get effective systems rolled out gradually in a human-in-the-loop setup.
Again, this is exactly what we've seen with coding systems. I think we'll see the same thing with automation, where basically robot plus human is much better than just human or just robot. That just makes total sense. It also makes it much easier to get all the technology bootstrapped. Because when it's robot plus human now, there's a lot more potential for the robot to actually learn on the job, acquire new skills.
Dwarkesh Patel 00:14:50
Because a human can label what's happening?
Sergey Levine 00:14:52
Also because the human can help, the human can give hints. Let me tell you this story. When we were working on the π0.5 project, the paper that we released last April, we initially controlled our robots with teleoperation in a variety of different settings. At some point we actually realized that we can actually make significant headway, once the model was good enough, by supervising it not just with low-level actions but actually literally instructing it through language.
Now you need a certain level of competence before you can do that, but once you have that level of competence, just standing there and telling the robot, "Okay, now pick up the cup, put the cup in the sink, put the dish in the sink," just with words already, actually gives the robot information that it can use to get better. Now imagine what this implies for the human plus robot dynamic.
Now basically, learning for these systems is not just learning from raw actions, it's also learning from words. Eventually it’ll be learning from observing what people do from the kind of natural feedback that you receive when you're doing a job together with somebody else. This is also the kind of stuff where the prior knowledge that comes from these big models is tremendously valuable, because that lets you understand that interaction dynamic. There's a lot of potential for these kinds of human plus robot deployments to make the model better.
Dwarkesh Patel 00:16:13
Interesting. I appreciate your patience with this question but I do want to concretely understand what is happening in the AI boom universe. I look at 2028 and we're building all these giant data centers. We're really constrained on labor, among other things. I look at what is happening at a site where a many-gigawatt data center is going up and everything is being assembled. Am I just seeing a bunch of robots that are moving around and picking things up and laying down solar panels and transformers and switchgear and stuff? Or am I seeing humans in 2028?
Sergey Levine 00:16:52
I would hope you'd see at least some robots. My sense is that if we get everything right, you really should. The place where there is a slider that'll move up and down depending on how much progress we make in the meantime, is the scope of responsibility that those machines get. Is the scope that they are issued a very specific task, they go and do that and then come back for the next assignment? Or is the scope that they're issued an area of responsibility that they take on? That's a place where there's very, very useful solutions at many different points in the spectrum. Where we land on that spectrum by 2028 will depend on our ability to handle all of the complex edge cases and handle them correctly.
Now construction is something where in some places it's extremely delicate, where you really have to do the right thing, and in other places it's more tolerant. That's basically the buffer for that scope. Again, the coding assistant LLMs are a really good analogy because here we have a great example of seeing a technology get deployed where its scope increases over time. Mapping that analogy onto robotics, probably gives us a pretty good sense of how it'll go down.
Dwarkesh Patel 00:18:08
Currently, where we are with LLMs, specifically LLMs for coding, they are able end-to-end to make simple applications, but they might not do exactly the thing you anticipate. If you get into a very complicated repository or something, their utility is harder to gauge and maybe might be negative. I don't know if you saw the METR paper on uplift. This level for coding, but for tasks in the physical world which are not some engineer figuring out how to make a turbine, but more just going out and doing things… What year is the GPT-5 equivalent for robotics?
Sergey Levine 00:18:50
So by GPT-5 equivalent you mean… I guess I would say GPT-5-equivalent means you're willing to delegate some basic things if you check that it was done correctly afterwards. 2028 through 2030 is a very reasonable timeline for that.
Just to better explain the parameters of this, scope means a few things. Scope means how much responsibility you're willing to delegate to the machine. But the other part is how much work the AI designers spend on getting that application right. One of the things that's going to change over time is that spinning up a new application is going to be easier and easier.
Right now where we are at in 2025 is that if we expend considerable effort in somewhat specialized data collection, and a little bit of specialized engineering, we can spin up some application that is maybe not quite production-ready but you can run it and it does stuff and hopefully that'll get to a production-ready level in a one-year-ish timeline. But the thing that'll go down over time is not just how much a person has to pay attention to it as it's doing stuff, but also how much we as the designers have to put in effort to make it work.
There's one difference between the work that robots do and the LLM stuff for coding. With coding you produce the code and then you just copy and paste it many times. Whereas with work there is value in doing it again. If you made one solar panel, you do it again and get a second solar panel. Whereas if you write some code, if you write that same code a second time that's not really useful. Those dynamics also make it more advantageous to have a system, even if it has limited scope. Simply by repeating the same thing a few times, you start getting value.
The reason I care about this so much is…obviously automation is good, productivity is good. But I also care about this because the more these things get out there, the closer we are to getting that self-sustaining data flywheel. To me it's really important, not just as a way to get robots out there and get them working, but also as a way to start making robots better and better through their own experience.
00:22:12 – Why robotics will scale faster than self-driving cars
Dwarkesh Patel 00:22:12
In terms of robotics progress, why won't it be like self-driving cars. It's been more than 10 years since Google launched its… Wasn't it in 2009 that they launched the self-driving car initiative? I remember when I was a teenager, watching demos where we would go buy a Taco Bell and drive back. Only now do we have them actually deployed. Even then they may make mistakes, etc. Maybe it'll be many more years before most of the cars are self-driving.
You're saying five years to this quite robust thing, but actually will it just feel like 20 years? Once we get the cool demo in five years, then it'll be another 10 years before we have the Waymo and the Tesla FSD working.
Sergey Levine 00:23:00
That's a really good question. One of the big things that is different now than it was in 2009 has to do with the technology for machine learning systems that understand the world around them. Principally for autonomous driving, this is perception. For robots, it can mean a few other things as well. Perception certainly was not in a good place in 2009. The trouble with perception is that it's one of those things where you can nail a really good demo with a somewhat engineered system, but hit a brick wall when you try to generalize it.
Now at this point in 2025, we have much better technology for generalizable and robust perception systems and, more generally, generalizable and robust systems for understanding the world around us. When you say that the system is scalable, in machine learning scalable really means generalizable. That gives us a much better starting point today. That's not an argument about robotics being easier than autonomous driving. It's just an argument for 2025 being a better year than 2009.
But there's also other things about robotics that are a bit different than driving. In some ways, robotic manipulation is a much, much harder problem. But in other ways, it's a problem space where it's easier to get rolling, to start that flywheel with a more limited scope. To give you an example, if you're learning how to drive, you would probably be pretty crazy to learn how to drive on your own without somebody helping you. You would not trust your teenage child to learn to drive just on their own, just drop them in the car and say, "Go for it." That's also a 16-year-old who's had a significant amount of time to learn about the world. You would never even dream of putting a five-year-old in a car and telling him to get started. But if you want somebody to clean the dishes, dishes can break too. But you would probably be okay with a child trying to do the dishes without somebody constantly sitting next to them with a brake, so to speak.
For a lot of tasks that we want to do with robotic manipulation, there's potential to make mistakes and correct those mistakes. When you make a mistake and correct it, well first you've achieved the task because you've corrected, but you've also gained knowledge that allows you to avoid that mistake in the future. With driving, because of the dynamics of how it's set up, it's very hard to make a mistake, correct it and then learn from it because the mistakes themselves have significant ramifications.
Not all manipulation tasks are that. There are truly some very safety-critical stuff. This is where the next thing comes in, which is common sense. Common sense, meaning the ability to make inferences about what might happen that are reasonable guesses, but that do not require you to experience that mistake and learn from it in advance. That's tremendously important. That's something that we basically had no idea how to do about five years ago. But now we can use LLMs and VLMs and ask them questions and they will make reasonable guesses. They will not give you expert behavior, but you can say, "Hey, there's a sign that says slippery floor. What's going to happen when I walk up over that?" It's pretty obvious, right? No autonomous car in 2009 would have been able to answer that question.
Common sense plus the ability to make mistakes and correct those mistakes, that's sounding an awful lot what a person does when they're trying to learn something. All of that doesn't make robotic manipulation easy necessarily, but it allows us to get started with a smaller scope and then grow from there.
Dwarkesh Patel 00:26:24
So for years, I mean not since 2009, but we've had lots of video data, language data, and transformers for 5-8 years. Lots of companies have tried to build transformer-based robots with lots of training data, including Google, Meta, et cetera. What is the reason that they've been hitting roadblocks? What has changed now?
Sergey Levine 00:26:51
That's a really good question. I'll start out with a slight modification to your comment. They've made a lot of progress. In some ways, a lot of the work that we're doing now at Physical Intelligence is built on the backs of lots of other great work that was done, for example, at Google. Many of us were at Google before. We were involved in some of that work. Some of it is work that we're drawing on that others did. There's definitely been a lot of progress there.
But to make robotic foundation models really work, it's not just a laboratory science experiment. It also requires industrial scale building effort. It's more like the Apollo program than it is a science experiment. The excellent research that was done in the past industrial research labs, and I was involved in much of that, was very much framed as a fundamental research effort. That's good. The fundamental research is really important, but it's not enough by itself. You need the fundamental research and you also need the impetus to make it real.
Making it real means actually putting the robots out there, getting data that is representative, the tasks that they need to do in the real world, getting that data at scale, building out the systems, and getting all that stuff right. That requires a degree of focus, a singular focus on really nailing the robotic foundation model for its own sake, not just as a way to do more science, not just as a way to publish a paper, and not just as a way to have a research lab.
Dwarkesh Patel 00:28:29
What is preventing you now from scaling that data even more? If data is a big bottleneck, why can't you just increase the size of your office 100x, have 100x more operators operating these robots and collecting more data. Why not ramp it up immediately 100x more?
Sergey Levine 00:28:49
That's a really good question. The challenge here is understanding which axes of scale contribute to which axes of capability. If we want to expand capability horizontally—meaning the robot knows how to do 10 things now and I'd like it to do 100 things later—that can be addressed by just directly horizontally scaling what we already have. But we want to get robots to a level of capability where they can do practically useful things in the real world.
That requires expanding along other axes too. It requires, for example, getting to very high robustness. It requires getting them to perform tasks very efficiently, quickly. It requires them to recognize edge cases and respond intelligently. Those things can also be addressed with scaling. But we have to identify the right axes for that, which means figuring out what data to collect, what settings to collect it in, what methods consume that data, and how those methods work.
Answering those questions more thoroughly will give us greater clarity on the axes, on those dependent variables, on the things that we need to scale. We don't fully know right now what that will look like. I think we'll figure it out pretty soon. It's something we're working on actively. We want to really get that right so that when we do scale it up, it'll directly translate into capabilities that are very relevant to practical use.
Dwarkesh Patel 00:30:11
Just to give an order of magnitude, how does the amount of data you have collected compare to internet-scale pre-training data? I know it's hard to do a token-by-token count, because how does video information compare to internet information, et cetera. But using your reasonable estimates, what fraction?
Sergey Levine 00:30:28
It's very hard to do because robotic experience consists of time steps that are very correlated with each other. The raw byte representation is enormous, but probably the information density is comparatively low. Maybe a better comparison is to the datasets that are used for multimodal training. And there, I believe last time we did that count, it was between one and two orders of magnitude.
Dwarkesh Patel 00:30:54
The vision you have of robotics, will it not be possible until you collect what, 100x, 1000x more data?
Sergey Levine 00:31:02
That's the thing, we don't know that. It's certainly very reasonable to infer that robotics is a tough problem. Probably it requires as much experience as the language stuff. But because we don't know the answer to that, to me a much more useful way to think about it is not how much data do we need to get before we're fully done, but how much data do we need to get before we can get started. That means before we can get a data flywheel that represents a self-sustaining and ever-growing data-collection recipe.
Dwarkesh Patel 00:31:34
When you say self-sustaining, is it just learning on the job or do you have something else in mind?
Sergey Levine 00:31:38
Learning on the job or acquiring data in a way such that the process of acquisition of that data itself is useful and valuable.
Dwarkesh Patel 00:31:47
I see. Some kind of RL.
Sergey Levine 00:31:49
Doing something actually real. Ideally I would like it to be RL, because with RL you can get away with the robot acting autonomously which is easier. But it's not out of the question that you can have mixed autonomy. As I mentioned before, robots can learn from all sorts of other signals. I described how we can have a robot that learns from a person talking to it. There's a lot of middle ground in between fully teleoperated robots and fully autonomous robots.
00:32:15 – How vision-language-action models work
Dwarkesh Patel 00:32:15
How does the π0 model work?
Sergey Levine 00:32:18
The current model that we have basically is a vision-language model that has been adapted for motor control. To give you a little bit of a fanciful brain analogy, a VLM, a vision-language model, is basically an LLM that has had a little pseudo visual cortex grafted to it, a vision encoder. Our models, they have a vision encoder, but they also have an action expert, an action decoder essentially. It has a little visual cortex and notionally a little motor cortex.
The way that the model makes decisions is it reads in the sensory information from the robot. It does some internal processing. That could involve outputting intermediate steps. You might tell it, "Clean up the kitchen." It might think to itself, "Hey, to clean up the kitchen, I need to pick up the dish and I need to pick up the sponge and I need to put this and this." Eventually it works its way through that chain-of-thought generation down to the action expert, which produces continuous actions.
That has to be a different module because the actions are continuous, they're high frequency. They have a different data format than text tokens. But structurally it's still an end-to-end transformer. Roughly speaking, technically, it corresponds to a mixture-of-experts architecture.
Dwarkesh Patel 00:33:29
And what is actually happening is that it's predicting "I should do X thing." Then there's an image token, then some action tokens –what it actually ends up doing– and then more image, more text description, more action tokens. Basically I'm looking at what stream is going on.
Sergey Levine 00:33:46
That's right, with the exception that the actions are not represented as discrete tokens. It actually uses flow matching and diffusion because they're continuous and you need to be very precise with your actions for dexterous control.
Dwarkesh Patel 00:33:56
I find it super interesting that you're using the open-source Gemma model, which is Google's LLM that they released open source, and then adding this action expert on top. I find it super interesting that the progress in different areas of AI is based on not only the same techniques, but literally the same model. You can just use an open-source LLM and add this action expert on top.
You naively might think that, “Oh, there's a separate area of research which is robotics, and there's a separate area of research called LLMs and natural language processing.” No, it's literally the same. The considerations are the same, the architectures are the same, even the weights are the same. I know you do more training on top of these open-source models, but I find that super interesting.
Sergey Levine 00:34:45
One theme here that is important to keep in mind is that the reason that those building blocks are so valuable is because the AI community has gotten a lot better at leveraging prior knowledge. A lot of what we're getting from the pre-trained LLMs and VLMs is prior knowledge about the world. It's a little bit abstracted knowledge. You can identify objects, you can figure out roughly where things are in image, that sort of thing.
But if I had to summarize in one sentence, the big benefit that recent innovations in AI give to robotics is the ability to leverage prior knowledge. The fact that the model is the same model, that's always been the case in deep learning. But it's that ability to pull in that prior knowledge, that abstract knowledge that can come from many different sources that's really powerful.
Dwarkesh Patel 00:36:44
I was talking to this researcher, Sander at GDM, and he works on video and audio models. He made the point that the reason, in his view, we aren't seeing that much transfer learning between different modalities. That is to say, training a language model on video and images doesn't seem to necessarily make it that much better at textual questions and tasks because images are represented at a different semantic level than text.
His argument is that text has this high-level semantic representation within the model, whereas images and videos are just compressed pixels. When they're embedded, they don't represent some high-level semantic information. They're just compressed pixels. Therefore there's no transfer learning at the level at which they're going through the model.
Obviously this is super relevant to the work you're doing. Your hope is that by training the model on the visual data that the robot sees, visual data generally maybe even from YouTube or whatever eventually, plus language information, plus action information from the robot itself, all of this together will make it generally robust. You had a really interesting blog post about why video models aren't as robust as language models. Sorry, this is not a super well-formed question. I just wanted to get a reaction.
Sergey Levine 00:38:09
Yeah, what’s up with that? I have maybe two things I can say there. I have some bad news and some good news. The bad news is what you're saying is really getting at the core of a long-running challenge with video and image generation models. In some ways, the idea of getting intelligent systems by predicting video is even older than the idea of getting intelligent systems by predicting text. The text stuff turned into practically useful things earlier than the video stuff did. I mean, the video stuff is great. You can generate cool videos. The work that's been done there recently is amazing. But it's not like just generating videos and images has already resulted in systems that have this deep understanding of the world where you can ask them to do stuff beyond just generating more images and videos. Whereas with language, clearly it has.
This point about representations is really key to it. One way we can think about it is this. Imagine pointing a camera outside this building, there's the sky, the clouds are moving around, the water, cars driving around, people. If you want to predict everything that'll happen in the future, you can do so in many different ways. You can say, "Okay, there's people around. Let me get really good at understanding the psychology of how people behave in crowds and predict the pedestrians." But you could also say, "Well, there's clouds moving around. Let me understand everything about water molecules and ice particles in the air." You could go super deep on that. If you want to fully understand down to the subatomic level everything that's going on, as a person you could spend decades just thinking about that and you'll never even get to the pedestrians or the water.
If you want to really predict everything that's going on in that scene, there's just so much stuff that even if you're doing a really great job and capturing 100% of something, by the time you get to everything else, ages will have passed. Whereas with text, it's already been abstracted into those bits that we as humans care about. The representations are already there. They're not just good representations, they focus on what really matters.
That's the bad news. Here's the good news. The good news is that we don't have to just get everything out of pointing a camera outside this building. When you have a robot, that robot is trying to do a job. It has a purpose, and its perception is in service to fulfilling that purpose. That is a really great focusing factor.
We know that for people, this really matters. Literally what you see is affected by what you're trying to do. There's been no shortage of psychology experiments showing that people have almost a shocking degree of tunnel vision where they will literally not see things right in front of their eyes if it's not relevant to what they're trying to achieve. That is tremendously powerful. There must be a reason why people do that. Certainly if you're out in the jungle, seeing more is better than seeing less. If you have that powerful focusing mechanism, it must be darn important for getting you to achieve your goal. Robots will have that focusing mechanism because they're trying to achieve a goal.
Dwarkesh Patel 00:41:10
The fact that video models aren't as robust, is that bearish for robotics? So much of the data you will have to use… I guess you're saying a lot of it will be labeled. Ideally, you just want to be able to throw everything on YouTube, every video we've ever recorded, and have it learn how the physical world works and how to move about. Just see humans performing tasks and learn from that. I guess you're saying it's hard to learn just from that and it needs to practice the task itself.
Sergey Levine 00:41:42
Let me put it this way. Let's say that I gave you lots of videotapes or lots of recordings of different sporting events and gave you a year to just watch sports. After that year, I told you, "Okay, now your job, you're going to be playing tennis." Okay, that's pretty dumb right? Whereas if I told you first you're going to be playing tennis and then I let you study up, now you really know what you're looking for.
There's a very real challenge here. I don't want to understate the challenge. But there's also a lot of potential for foundation models that are embodied, that learn from interaction, from controlling robotic systems, to be better at absorbing the other data sources because they know what they're trying to do. I don't think that by itself is a silver bullet. I don't think it solves everything, but it does help a lot. We've already seen the beginnings of that where we can see that including web data in training for robots really does help with generalization. I have the suspicion that in the long run, it'll make it easier to use those sources of data that have been tricky to use up until now.
Dwarkesh Patel 00:42:50
Famously, LLMs have all these emergent capabilities that were never engineered in, because somewhere in internet text is the data to train and to be able to give it the knowledge to do a certain kind of thing. With robots, it seems like you are collecting all the data manually. So there won't be this mysterious new capability that is somewhere in the dataset that you haven't purposefully collected.
Which seems like it should make it even harder to then have robust, out-of-distribution capabilities. I wonder if the trek over the next 5-10 years will be like this: Each subtask, you have to give it thousands of episodes. Then it's very hard to actually automate much work just by doing subtasks. If you think about what a barista does, what a waiter does, what a chef does, very little of it involves just sitting at one station and doing stuff. You got to move around, you got to restock, you got to fix the machine, et cetera, go between the counter and the cashier and the machine, etc.
Will there just be this long tail of things and skills that you have to keep adding episodes for manually and labeling and seeing how well they did? Or is there some reason to think that it will progress more generally than that?
Sergey Levine 00:44:10
There's a subtlety here. Emergent capabilities don't just come from the fact that internet data has a lot of stuff in it. They also come from the fact that generalization, once it reaches a certain level, becomes compositional. There was a cute example that one of my students really liked to use in some of his presentations. You know what the International Phonetic Alphabet (IPA) is?
Dwarkesh Patel 00:44:35
No.
Sergey Levine 00:44:36
If you look in a dictionary, they'll have the pronunciation of a word written in funny letters. That's basically International Phonetic Alphabet. It's an alphabet that is pretty much exclusively used for writing down pronunciations of individual words and dictionaries. You can ask an LLM to write you a recipe for making some meal in International Phonetic Alphabet, and it will do it. That's like, holy crap. That is definitely not something that it has ever seen because IPA is only ever used for writing down pronunciations of individual words.
That's compositional generalization. It's putting together things you've seen in new ways. Arguably there's nothing profoundly new here because yes, you've seen different words written that way, but you've figured out that now you can compose the words in this other language the same way that you've composed words in English. That's actually where the emergent capabilities come from. Because of this, in principle, if we have a sufficient diversity of behaviors, the model should figure out that those behaviors can be composed in new ways as the situation calls for it.
We've actually seen things even with our current models. In the grand scheme of things, looking back five years from now, we'll probably think that these are tiny in scale. But we've already seen what I would call emerging capabilities. When we were playing around with some of our laundry folding policies, we actually discovered this by accident. The robot accidentally picked up two T-shirts out of the bin instead of one. It starts folding the first one, the other one gets in the way, picks up the other one, throws it back in the bin. We didn't know it would do that. Holy crap.
Then we tried to play around with it, and yep, it does that every time. It's doing its work. Drop something else on the table, it just picks it up and puts it back. Okay, that's cool. It starts putting things in a shopping bag. The shopping bag tips over, it picks it back up, and stands it upright. We didn't tell anybody to collect data for that. I'm sure somebody accidentally at some point, or maybe intentionally picked up the shopping bag.
You just have this kind of compositionality that emerges when you do learning at scale. That's really where all these remarkable capabilities come from. Now you put that together with language. You put that together with all sorts of chain-of-thought reasoning, and there's a lot of potential for the model to compose things in new ways.
Dwarkesh Patel 00:46:45
Right. I had an example like this when I got a tour of the robots at your office. It was folding shorts. I don't know if there was an episode like this in the training set, but just for fun I took one of the shorts and turned it inside out. Then it was able to understand that it first needed to get… First of all, the grippers are just like this, two opposable finger and thumb-like things. It's actually shocking how much you can do with just that. But it understood that it first needed to fold it inside out before folding it correctly.
What's especially surprising about that is it seems like this model only has one second of context. Language models can often see the entire codebase. They're observing hundreds of thousands of tokens and thinking about them before outputting. They're observing their own chain of thought for thousands of tokens before making a plan about how to code something up. Your model is seeing one image, what happened in the last second, and it vaguely knows it's supposed to fold this short. It's seeing the image of what happened in the last second. I guess it works.
It's crazy that it will just see the last thing that happened and then keep executing on the plan. Fold it inside out, then fold it correctly. But it's shocking that a second of context is enough to execute on a minute-long task. Yeah. I'm curious why you made that choice in the first place and why it's possible to actually do tasks… If a human only had a second of memory and had to do physical work, I feel like that would just be impossible.
Sergey Levine 00:48:23
It's not that there's something good about having less memory, to be clear. Adding memory, adding longer context, all that stuff, adding higher resolution images, those things will make the model better. But the reason why it's not the most important thing for the kind of skills that you saw when you visited us, at some level, comes back to Moravec's paradox.
Moravec's paradox basically, if you want to know one thing about robotics, that's the thing. Moravec's paradox says that in AI the easy things are hard and the hard things are easy. Meaning the things that we take for granted—like picking up objects, seeing, perceiving the world, all that stuff—those are all the hard problems in AI. The things that we find challenging, like playing chess and doing calculus, actually are often the easier problems.
I think this memory stuff is actually Moravec’s paradox in disguise. We think that the cognitively demanding tasks that we do that we find hard, that cause us to think, "Oh man, I'm sweating. I'm working hard." Those are the ones that require us to keep lots of stuff in memory, lots of stuff in our minds. If you're solving some big math problem, if you're having a complicated technical conversation on a podcast, those are things where you have to keep all those puzzle pieces in your head.
If you're doing a well-rehearsed task—if you are an Olympic swimmer and you're swimming with perfect form—and you're right there in the zone, people even say it's "in the moment." It's in the moment. It's like you've practiced it so much you've baked it into your neural network in your brain. You don't have to think carefully about keeping all that context. It really is just Moravec's paradox manifesting itself.
That doesn't mean that we don't need the memory. It just means that if we want to match the level of dexterity and physical proficiency that people have, there's other things we should get right first and then gradually go up that stack into the more cognitively demanding areas, into reasoning, into context, into planning, all that kind of stuff. That stuff will be important too.
00:50:26 – Improvements needed for brainlike efficiency
Dwarkesh Patel 00:50:26
You have this trilemma. You have three different things which all take more compute during inference that you want to increase at the same time. You have the inference speed. Humans are processing 24 frames a second or whatever it is. We can react to things extremely fast. Then you have the context length. For the kind of robot which is just cleaning up your house, I think it has to be aware of things that happened minutes ago or hours ago and how that influences its plan about the next task it's doing. Then you have the model size. At least with LLMs, we've seen that there's gains from increasing the amount of parameters.
I think currently you have 100 millisecond inference speeds. You have a second-long context and then the model is a couple billion parameters? Each of these, at least two of them, are many orders of magnitude smaller than what seems to be the human equivalent. A human brain has trillions of parameters and this has like 2 billion parameters. Humans are processing at least as fast as this model, actually a decent bit faster, and we have hours of context. It depends on how you define human context, but hours of context, minutes of context.
Sergey Levine 00:51:46
Sometimes decades of context.
Dwarkesh Patel 00:51:47
Exactly. You have to have many order-of-magnitude improvements across all of these three things which seem to oppose each other. Increasing one reduces the amount of compute you can dedicate towards the other one in inference. How are we going to solve this?
Sergey Levine 00:52:06
That's a very big question. Let's try to unpack this a little bit. There's a lot going on in there. One thing is a really interesting technical problem. It's something where we'll see perhaps a lot of really interesting innovation over the next few years. It’s the question of representation for context.
You gave some of the examples, like if you have a home robot that's doing something then it needs to keep track. As a person, there are certainly some things where you keep track of them very symbolically, almost in language. I have my checklist. I'm going shopping. At least for me, I can literally visualize in my mind my checklist. Pick up the yogurt, pick up the milk, pick up whatever. I'm not picturing the milk shelf with the milk sitting there. I'm just thinking, “milk.”
But then there's other things that are much more spatial, almost visual. When I was trying to get to your studio, I was thinking, "Okay, here's what the street looks like. Here's what that street looks like. Here's what I expect the doorway to look like."
Representing your context in the right form, that captures what you really need to achieve your goal—and otherwise discards all the unnecessary stuff—I think that's a really important thing. We're seeing the beginnings of that with multimodal models. But I think that multimodality has much more to it than just image plus text. That's a place where there's a lot of room for really exciting innovation.
Dwarkesh Patel 00:53:40
Do you mean in terms of how we represent?
Sergey Levine 00:53:44
How we represent both context, both what happened in the past, and also plans or reasoning, as you call it in the LLM world, which is what we would like to happen in the future or intermediate processing stages in solving a task. Doing that in a variety of modalities, including potentially learned modalities that are suitable for the job, is something that has enormous potential to overcome some of these challenges.
Dwarkesh Patel 00:54:06
Interesting. Another question I have as we're discussing these tough trade-offs in terms of inference is comparing it to the human brain. The human brain is able to have hours, decades of context while being able to act on the order of 10 milliseconds, while having 100 trillion parameters or however you want to count it. I wonder if the best way to understand what's happening here is that human brain hardware is just way more advanced than the hardware we have with GPUs, or that the algorithms for encoding video information are way more efficient. Maybe it's some crazy mixture of experts where the active parameters are also on the order of billions, low billions. Or it’s some mixture of the two.
If you had to think about why we have these models that are, across many dimensions, orders of magnitude less efficient compared to the brain, is it hardware or algorithms?
Sergey Levine 00:55:13
That's a really good question. I definitely don't know the answer to this. I am not by any means well-versed in neuroscience. If I had to guess and also provide an answer that leans more on things I know, it's something like this. The brain is extremely parallel. It has to be just because of the biophysics, but it's even more parallel than your GPU.
If you think about how a modern multimodal language model processes the input, if you give it some images and some text, first it reads in the images, then it reads in the text, and then proceeds one token at a time to generate the output. It makes a lot more sense to me for an embodied system to have parallel processes. Now mathematically you can make close equivalences between parallel and sequential stuff. Transformers aren't fundamentally sequential. You make them sequential by putting in position embeddings. Transformers are fundamentally very parallelizable things. That's what makes them so great.
I don't think that mathematically this highly parallel thing—where you're doing perception and proprioception and planning all at the same time—necessarily needs to look that different from a transformer, although its practical implementation will be different. You could imagine that the system will in parallel think about, "Okay, here's my long-term memory, here's what I've seen a decade ago, here's my short-term spatial stuff, here's my semantic stuff, here's what I'm seeing now, here's what I'm planning." All of that can be implemented in a way that there's some very familiar attentional mechanism, but in practice all running in parallel, maybe at different rates, maybe with the more complex things running slower, the faster reactive stuff running faster.
Dwarkesh Patel 00:57:54
If in five years we have a system which is as robust as a human in terms of interacting with the world, then what has happened that makes it physically possible to be able to run those models? To have video information that is streaming at real time, or hours of prior video information is somehow being encoded and considered while decoding in a millisecond scale, and with many more parameters. Is it just that Nvidia has shipped much better GPUs or that you guys have come up with much better encoders and stuff? What's happened in the five years?
Sergey Levine 00:58:30
There are a lot of things to this question. Certainly there's a really fascinating systems problem. I'm by no means a systems expert. I would imagine that the right architecture in practice, especially if you want an affordable low-cost system, would be to externalize at least part of the thinking. You could imagine in the future you'll have a robot where, if your Internet connection is not very good, the robot is in a dumber reactive mode. But if you have a good Internet connection then it can be a little smarter. It's pretty cool.
There is also research and algorithms stuff that can help here, figuring out the right representations, concisely representing both your past observations but also changes in observation. Your sensory stream is extremely temporally correlated. The marginal information gained from each additional observation is not the same as the entirety of that observation. The image that I'm seeing now is very correlated to the image I saw before. In principle, I want to represent it concisely. I could get away with a much more compressed representation than if I represent the images independently. There's a lot that can be done on the algorithm side to get this right. That's really interesting algorithms work.
There's also a really fascinating systems problem. To be truthful, I haven't gotten to the systems problem because you want to implement the system once you know the shape of the machine learning solution. But there's a lot of cool stuff to do there.
Dwarkesh Patel 00:59:49
Maybe you guys just need to hire the people who run the YouTube data centers because they know how to encode video information.
This raises an interesting question. With LLMs, theoretically you could run your own model on this laptop or whatever. Realistically what happens is that the largest, most effective models are being run in batches of thousands and millions of users at the same time, not locally. Will the same thing happen in robotics because of the inherent efficiencies of batching, plus the fact that we have to do this incredibly compute-intensive inference task? You don't want to be carrying around $50,000 GPUs per robot or something. You just want that to happen somewhere else.
In this robotics world, should we just be anticipating something where you need connectivity everywhere? You need robots that are super fast. You're streaming video information back and forth, or at least video information one way. Does that have interesting implications about how this deployment of robots will be instantiated?
Sergey Levine 01:01:00
I don't know. But if I were to guess, I would guess that we'll see both. That we'll see low-cost systems with off-board inference and more reliable systems. For example, in settings where you have an outdoor robot or something where you can't rely on connectivity, those will be costlier and have onboard inference.
I'll say a few things from a technical standpoint that might contribute to understanding this. While a real-time system obviously needs to be controlled in real time, often at high frequency, the amount of thinking you need to do for every time step might be surprisingly low. Again, we see this in humans and animals. When we plan out movements, there is definitely a real planning process that happens in the brain. If you record from a monkey brain, you will find neural correlates of planning. There is something that happens in advance of a movement. When that movement takes place, the shape of the movement correlates with what happened before the movement. That's planning.
That means that you put something in place and set the initial conditions of some process and then unroll that process, and that's the movement. That means that during that movement, you're doing less processing and you batch it up in advance. But you're not entirely an open loop. It's not that you're playing back a tape recorder. You are reacting as you go. You're just reacting at a different level of abstraction, a more basic level of abstraction.
Again, this comes back to representations. Figure out which representati ons are sufficient for planning in advance and then unrolling, and which representations require a tight feedback loop. For that tight feedback loop, what are you doing feedback on? If I'm driving a vehicle, maybe I'm doing feedback on the position of the lane marker so that I stay straight. At a lower frequency, I sort of gauge where I am in traffic.
01:02:48 – Learning from simulation
Dwarkesh Patel 01:02:48
You have a couple of lectures from a few years back where you say that even for robotics, RL is in many cases better than imitation learning. But so far the models are exclusively doing imitation learning. I'm curious how your thinking on this has changed. Maybe it hasn’t changed. But then you need to do this for the RL. Why can't you do RL yet?
Sergey Levine 01:03:09
The key here is prior knowledge. In order to effectively learn from your own experience, it turns out that it's really, really important to already know something about what you're doing. Otherwise it takes far too long, just like it takes a person, when they're a child, a very long time to learn very basic things, to learn to write for the first time, for example. Once you already have some knowledge, then you can learn new things very quickly. The purpose of training the models with supervised learning now is to build out that foundation that provides the prior knowledge so they can figure things out much more quickly later.
Again, this is not a new idea. This is exactly what we've seen with LLMs. LLMs start off being trained purely with next token prediction. That provided an excellent starting point, first for all sorts of synthetic data generation and then for RL. It makes total sense that we would expect basically any foundation model effort to follow that same trajectory. We first build out the foundation essentially in a somewhat brute-force way. The stronger that foundation gets, the easier it is to then make it even better with much more accessible training.
Dwarkesh Patel 01:04:15
In 10 years, will the best model for knowledge work also be a robotics model or have an action expert attached to it? The reason I ask is, so far we've seen advantages from using more general models for things. Will robotics fall into this bucket? Will we just have the model which does everything, including physical work and knowledge work, or do you think they'll continue to stay separate?
Sergey Levine 01:04:40
I really hope that they will actually be the same. Obviously I'm extremely biased. I love robotics, I think it's very fundamental to AI. But optimistically, I hope it's actually the other way around, that the robotics element of the equation will make all the other stuff better.
There are two reasons for this that I can tell you about. One has to do with representations and focus. What I said before, with video prediction models if you just want to predict everything that happens, it's very hard to figure out what's relevant. If you have the focus that comes from trying to do a task now that acts to structure how you see the world in a way that allows you to more fruitfully utilize the other signals. That could be extremely powerful.
The second one is that understanding the physical world at a very deep, fundamental level, at a level that goes beyond just what we can articulate with language, can help you solve other problems. We experience this all the time. When we talk about abstract concepts, we say, “This company has a lot of momentum.” We'll use social metaphors to describe inanimate objects. “My computer hates me.” We experience the world in a particular way and our subjective experience shapes how we think about it in very profound ways. Then we use that as a hammer to basically hit all sorts of other nails that are far too abstract to handle any other way.
Dwarkesh Patel 01:06:04
There might be other considerations that are relevant to physical robots in terms of inference speed and model size, et cetera, which might be different from the considerations for knowledge work. Maybe it's still the same model, but then you can serve it in different ways. The advantages of co-training are high enough.
I'm wondering, in five years if I'm using a model to code for me, does it also know how to do robotics stuff? Maybe the advantages of code writing on robotics are high enough that it's worth it.
Sergey Levine 01:06:36
The coding is probably the pinnacle of abstract knowledge work in the sense that just by the mathematical nature of computer programming, it's an extremely abstract activity, which is why people struggle with it so much.
Dwarkesh Patel 01:06:49
I'm a bit confused about why simulation doesn't work better for robots. If I look at humans, smart humans do a good job of, if they're intentionally trying to learn, noticing what about the simulation is similar to real life and paying attention to that and learning from that.
If you have pilots who are learning in simulation or F1 drivers who are learning in simulation, should we expect it to be the case that as robots get smarter they will also be able to learn more things through simulation? Or is this cursed and we need real-world data forever?
Sergey Levine 01:07:23
This is a very subtle question. Your example with the airplane pilot using simulation is really interesting. But something to remember is that when a pilot is using a simulator to learn to fly an airplane, they're extremely goal-directed. Their goal in life is not to learn to use a simulator. Their goal in life is to learn to fly the airplane. They know there will be a test afterwards. They know that eventually they'll be in charge of a few hundred passengers and they really need to not crash that thing.
When we train models on data from multiple different domains, the models don't know that they're supposed to solve a particular task. They just see, "Hey, here's one thing I need to master. Here's another thing I need to master." Maybe a better analogy there is if you're playing a video game where you can fly an airplane and then eventually someone puts you in the cockpit of a real one. It's not that the video game is useless, but it's not the same thing. If you're trying to play that video game and your goal is to really master the video game, you're not going to go about it in quite the same way.
Dwarkesh Patel 01:08:21
Can you do some kind of meta-RL on this? There's this really interesting paper you wrote in 2017. Maybe the loss function is not how well it does at a particular video game or particular simulation. I'll let you explain it. But it was about how well being trained at different video games makes it better at some other downstream task. I did a terrible job at explaining but can you do a better job and try to explain what I was trying to say?
Sergey Levine 01:08:46
What you're trying to say is that maybe if we have a really smart model that's doing meta-learning, perhaps it can figure out that its performance on a downstream problem, a real-world problem, is increased by doing something in a simulator.
Dwarkesh Patel 01:08:59
And then specifically make that the loss function, right?
Sergey Levine 01:09:02
That's right. But here's the thing with this. There's a set of these ideas that are all going to be something like, “Train to make it better on the real thing by leveraging something else.” The key linchpin for all of that is the ability to train it to be better on the real thing. I suspect in reality we might not even need to do something quite so explicit. Meta learning is emergent, as you pointed out before. LLMs essentially do a kind of meta learning via in-context learning. We can debate how much that's learning or not, but the point is that large powerful models trained on the right objective and on real data, get much better at leveraging all the other stuff. I think that's actually the key.
Coming back to your airplane pilot, the airplane pilot is trained on a real world objective. Their objective is to be a good airplane pilot, to be successful, to have a good career. All of that kind of propagates back into the actions they take and leveraging all these other data sources. So what I think is actually the key here to leveraging auxiliary data sources including simulation, is to build the right foundation model that is really good and has those emergent abilities. To your point, to get really good like that, it has to have the right objective. Now we know how to get the right objective out of real world data, maybe we can get it out of other things, but that's harder right now.
Again, we can look to the examples of what happened in other fields. These days if someone trains an LLM for solving complex problems, they're using lots of synthetic data. The reason they're able to leverage that synthetic data effectively is because they have this starting point that is trained on lots of real data that gets it. Once it gets it, then it's more able to leverage all this other stuff. Perhaps ironically, the key to leveraging other data sources including simulation, is to get really good at using real data, understand what's up with the world, and then you can fruitfully use all this stuff.
Dwarkesh Patel 01:10:51
Once we have, in 2035 or 2030, basically this sci-fi world, are you optimistic about the ability of true AGIs to build simulations in which they are rehearsing skills that no human or AI has ever had a chance to practice before? They need to practice to be astronauts because we're building the Dyson sphere and they can just do that in simulation. Or will the issue with simulation continue to be one regardless of how smart the models get?
Sergey Levine 01:11:21
Here’s what I would say. Deep down at a very fundamental level, the synthetic experience that you create yourself doesn't allow you to learn more about the world. It allows you to rehearse things, it allows you to consider counterfactuals. But somehow information about the world needs to get injected into the system. The way you pose this question elucidates this very nicely. In robotics classically, people have often thought about simulation as a way to inject human knowledge. A person knows how to write down differential equations, they can code it up and that gives the robot more knowledge than it had before.
But increasingly what we're learning from experiences in other fields, from how the video generation stuff goes from synthetic data for LLMs, is that probably the most powerful way to create synthetic experience is from a really good model. The model probably knows more than a person does about those fine-grained details. But then of course, where does that model get the knowledge? From experiencing the world.
In a sense, what you said is quite right in that a very powerful AI system can simulate a lot of stuff. But also at that point it almost doesn't matter because, viewed as a black box, what's going on with that system is that information comes in and capability comes out. Whether the way to process that information is by imagining some stuff and simulating or by some model-free method is kind of irrelevant in our understanding of its capabilities.
Dwarkesh Patel 01:12:46
Do you have a sense of what the equivalent is in humans? Whatever we're doing when we're daydreaming or sleeping. I don't know if you have some sense of what this auxiliary thing we're doing is, but if you had to make an ML analogy, what is it?
Sergey Levine 01:13:01
Certainly when you sleep your brain does stuff that looks an awful lot like what it does when it's awake. It looks an awful lot like playing back experience or perhaps generating new statistically similar experience. It's very reasonable to guess that perhaps simulation through a learned model is part of how your brain figures out counterfactuals, basically.
Something that's even more fundamental than that is that optimal decision making at its core, regardless of how you do it, requires considering counterfactuals. You basically have to ask yourself, “If I did this instead of that, would it be better?” You have to answer that question somehow. Whether you answer that question by using a learned simulator, or whether you answer that question by using a value function or something, by using a reward model, in the end it's all the same. As long as you have some mechanism for considering counterfactuals and figuring out which counterfactual is better, you've got it. I like to think about it this way because it simplifies things. It tells us that the key is not necessarily to do really good simulations. The key is to figure out how to answer counterfactuals.
01:14:08 – How much will robots speed up AI buildouts?
Dwarkesh Patel 01:14:08
Yeah, Interesting. Stepping into the big picture again. The reason I'm interested in getting a concrete understanding of when this robot economy will be deployed is because it's relevant to understanding how fast AGI will proceed in the sense that it's obviously about the data flywheel.
But also, if you just extrapolate out the capex for AI by 2030, people have different estimates, but many people have estimates in the hundreds of gigawatts – 100, 200, 300 gigawatts. You can just crunch numbers on having 100-200 gigawatts deployed by 2030. The marginal capex per year is in the trillions of dollars. It's $2-4 trillion dollars a year. That corresponds to actual data centers you have to build, actual chip foundries you have to build, actual solar panel factories you have to build.
I am very curious about whether by 2030, the big bottleneck is just the people to lay out the solar panels next to the data center or assemble the data center, or will the robot economy be mature enough to help significantly in that process.
Sergey Levine 01:15:23
That's cool. You're basically saying, how much concrete should I buy now to build the data center so that by 2030 I can power all the robots. That is a more ambitious way of thinking about it than has occurred to me, but it's a cool question. The good thing, of course, is that the robots can help you build that stuff.
Dwarkesh Patel 01:15:38
But will they be able to by that time? There's the non-robotic stuff, which will also mandate a lot of capex. Then there's robot stuff where you have to build robot factories, etc. There will be this industrial explosion across the whole stack. How much will robotics be able to speed that up or make it possible?
Sergey Levine 01:15:59
In principle, quite a lot. We have a tendency sometimes to think about robots as mechanical people, but that's not the case. People are people and robots are robots. The better analogy for the robot, it's like your car or a bulldozer. It has much lower maintenance requirements. You can put them into all sorts of weird places and they don't have to look like people at all. You can make a robot that's 100 feet tall. You can make a robot that's tiny.
If you have the intelligence to power very heterogeneous robotic systems, you can probably do a lot better than just having mechanical people, in effect. It can be a big productivity boost for real people and it can allow you to solve problems that are very difficult to solve. For example, I'm not an expert on data centers by any means, but you could build your data centers in a very remote location because the robots don't have to worry about whether there's a shopping center nearby.
Dwarkesh Patel 01:16:59
There's the question of where the software will be, and then there's the question of how many physical robots we will have. How many of the robots you're training in Physical Intelligence, these tabletop arms, are there physically in the world? How many will there be by 2030? These are tough questions, how many will be needed for the intelligence explosion.
Sergey Levine 01:17:21
These are very tough questions. Also, economies of scale in robotics so far have not functioned the same way that they probably would in the long term. Just to give you an example, when I started working in robotics in 2014, I used a very nice research robot called a PR2 that cost $400,000 to purchase. When I started my research lab at UC Berkeley, I bought robot arms that were $30,000. The robots that we are using now at Physical Intelligence, each arm costs about $3,000. We think they can be made for a small fraction of that.
Dwarkesh Patel 01:17:59
What is the cause of that learning rate?
Sergey Levine 01:18:01
There are a few things. One, of course, has to do with economies of scale. Custom-built, high-end research hardware, of course, is going to be much more expensive than more productionized hardware. Then of course, there's a technological element. As we get better at building actuated machines, they become cheaper.
There's also a software element. The smarter your AI system gets, the less you need the hardware to satisfy certain requirements. Traditional robots in factories need to make motions that are highly repeatable. Therefore it requires a degree of precision and robustness that you don't need if you can use cheap visual feedback. AI also makes robots more affordable and lowers the requirements on the hardware.
Dwarkesh Patel 01:18:50
Interesting. Do you think the learning rate will continue? Do you think it will cost hundreds of dollars by the end of the decade to buy mobile arms?
Sergey Levine 01:18:58
That is a great question for my co-founder, Adnan Esmail, who is probably the best person arguably in the world to ask that question. Certainly the drop in cost that I've seen has surprised me year after year.
Dwarkesh Patel 01:19:11
How many arms are there probably in the world? Is it more than a million? Less than a million?
Sergey Levine 01:19:15
I don't know the answer to that question, but it's also a tricky question to answer because not all arms are made equal. Arguably, the robots that are assembling cars in a factory are just not the right kind to think about.
Dwarkesh Patel 01:19:27
The kind you want to train on.
Sergey Levine 01:19:28
Very few because they are not currently commercially deployed as factory robots.
Dwarkesh Patel 01:19:35
Less than 100,000?
Sergey Levine 01:19:37
I don't know, but probably.
Dwarkesh Patel 01:19:38
Okay. And we want billions of robots, at least millions of robots. If you're just thinking about the industrial explosion that you need to get this explosive AI growth, not only do you need the arms, but you need something that can move around. Basically, I'm just trying to think whether that will be possible by the time that you need a lot more labor to power this AI boom?
Sergey Levine 01:20:09
Well, economies are very good at filling demand when there's a lot of demand. How many iPhones were in the world in 2001? There's definitely a challenge there. It's something that is worth thinking about. A particularly important question for researchers like myself is how can AI affect how we think about hardware?
There are some things that are going to be really, really important. You probably want your thing to not break all the time. There are some things that are firmly in that category of question marks. How many fingers do we need? You said yourself before that you were surprised that a robot with two fingers can do a lot. Maybe you still want more than that, but still finding the bare minimum that still lets you have good functionality, that's important. That's in the question mark box.
There are some things that we probably don't need. We probably don't need the robot to be super duper precise, because we know that feedback can compensate for that. My job, as I see it right now, is to figure out what's the minimal package we can get away with. I really think about robots in terms of minimal package because I don't think that we will have the one ultimate robot, the mechanical person basically.
What we will have is a bunch of things that good, effective robots need to satisfy. Just like good smartphones need to have a touchscreen. That's something that we all agreed on. Then they’ll need a bunch of other stuff that's optional, depending on the need, depending on the cost point, et cetera. There will be a lot of innovation where once we have very capable AI systems that can be plugged into any robot to endow it with some basic level of intelligence, then lots of different people can innovate on how to get the robot hardware to be optimal for each niche.
Dwarkesh Patel 01:21:48
In terms of manufacturers, is there some Nvidia of robotics?
Sergey Levine 01:21:52
Not right now. Maybe there will be someday. Maybe I'm being idealistic, but I would really like to see a world where there's a lot of heterogeneity in robots.
Dwarkesh Patel 01:22:03
What is the biggest bottleneck in the hardware today as somebody who's designing the algorithms that run on it?
Sergey Levine 01:22:06
It's a tough question to answer, mainly because things are changing so fast. To me, the things that I spend a significant amount of time thinking about on the hardware side is really more reliability and cost. It's not that I'm that worried about cost. It's just that cost translates to the number of robots, which translates to the amount of data. Being an ML person, I really like having lots of data. I really want to have robots that are low cost, because then I can have more of them and therefore more data. Reliability is important, more or less for the same reason.
It's something that we'll get more clarity on as things progress. Basically, the AI systems of today are not pushing the hardware to the limit. As the AI systems get better and better, the hardware will get pushed to the limit, and then we'll hopefully have a much better answer to your question.
01:22:54 – If hardware’s the bottleneck, does China win by default?
Dwarkesh Patel 01:22:54
This is a question I've had for a lot of guests. If you go through any layer of this AI explosion, you find that a bunch of the actual source supply chain is being manufactured in China, other than chips obviously. You talk about data centers and you're like, “Oh, all the wafers for solar panels and a bunch of the cells and modules, et cetera, are manufactured in China.” You just go through the supply chain. Obviously robot arms are being manufactured in China.
You’ll live in this world where it’s just incredibly valuable to ramp up manufacturing of the hardware, because each robot can produce some fraction of the value that a human worker can produce. Not only is that true, but the value of human workers or any worker has tremendously skyrocketed because we need tons of bodies to lay out the tens of thousands of acres of solar farms and data centers and foundries and everything.
In this boom world, the big bottleneck there's just how many robots can you physically deploy? How many can you manufacture? Because you guys are going to come up with the algorithms now. We just need the hardware. This is a question I've asked many guests. If you look at the part of the chain that you are observing, what is the reason that China just doesn't win by default? If they're producing all the robots and you come up with the algorithms that make those robots super valuable, why don't they just win by default?
Sergey Levine 01:24:33
This is a very complex question. I'll start with the broader themes and then try to drill a little bit into the details. One broader theme here is that if you want to have an economy where you get ahead by having a highly educated workforce—by having people that have high productivity, meaning that for each person's hour of work, lots of stuff gets done—automation is really, really good. Automation is what multiplies the amount of productivity that each person has. Again, it’s the same as LLM coding tools. LLM coding tools amplify the productivity of a software engineer. Robots will amplify the productivity of basically everybody that is doing work.
Now that's a final state, a desirable final state. There's a lot of complexity in how you get to that state, how you make that an appealing journey to society, how you navigate the geopolitical dimension of that. All of that stuff is pretty complicated. It requires making a number of really good decisions. Good decisions about investing in a balanced robotics ecosystem, supporting both software innovation and hardware innovation. I don't think any of those are insurmountable problems. It just requires a degree of long-term vision and the right balance of investment.
What makes me really optimistic about this is the final state. We can all agree that in the United States we would like to have a society where people are highly productive, where we have highly educated people doing high-value work. Because that end state seems to me very compatible with automation, with robotics, at some level there should be a lot of incentive to get to that state.
Then from there we have to solve for all the details that will help us get there. That's not easy. There's a lot of complicated decisions that need to be made in terms of private industry, in terms of investment, in terms of the political dimension. But I'm very optimistic about it because it seems to me that the light at the end of the tunnel is in the right direction.
Dwarkesh Patel 01:26:54
I guess there's a different question. If the value is bottlenecked by hardware and you just need to produce more hardware, what is the path by which hundreds of millions of robots or billions of robots are being manufactured in the US or with allies? I don't know how to approach that question, but it seems like a different question than, “Well, what is the impact on human wages or something?”
Sergey Levine 01:27:16
For the specifics of how we make that happen, that's a very long conversation that I'm probably not the most qualified to speak to. But in terms of the ingredients, the ingredient here that is important is that robots help with physical things, physical work. If producing robots is itself physical work, then getting really good at robotics should help with that.
It's a little circular, of course, and as with all circular things, you have to bootstrap it and try to get that engine going. But it seems like it is an easier problem to address than, for example, the problem of digital devices. Work goes into creating computers, phones, et cetera. But the computers and phones don't themselves help with the work.
Dwarkesh Patel 01:28:05
Right. I guess feedback loops go both ways. They can help you or they can help others and it's a positive sum world. It's not necessarily bad that they help others. But to the extent that a lot of the things which would go into this feedback loop—the sub-component, manufacturing and supply chain, already exist in China—it seems like the stronger feedback loop would exist in China. Then there's a separate discussion. Maybe that's fine, maybe that's good, and maybe they'll continue exporting this to us. But I just find it notable that whenever I talk to guests about different things, it's just like, “Yeah, within a few years the key bottleneck to every single part of the supply chain here will be something that China is the 80% world supplier of.”
Sergey Levine 01:28:49
This is why I said before that something really important to get right here is a balanced robotics ecosystem. AI is tremendously exciting, but we should also recognize that getting AI right is not the only thing that we need to do. We need to think about how to balance our priorities, our investment, the kind of things that we spend our time on. Just as an example, at Physical Intelligence we do take hardware very seriously. We build a lot of our own things and we want to have a hardware roadmap alongside our AI roadmap. But that's just us.
For the United States, arguably for human civilization as a whole, we need to think about these problems very holistically. It is easy to get distracted sometimes when there's a lot of excitement, a lot of progress in one area like AI. We are tempted to lose track of other things, including things you've said. There's a hardware component. There's an infrastructure component with compute and things like that. In general it's good to have a more holistic view of these things. I wish we had more holistic conversations about that sometimes.
Dwarkesh Patel 01:30:03
From the perspective of society as a whole, how should they be thinking about the advances in robotics and knowledge work? Basically society should be planning for full automation. There will be a period in which people's work is way more valuable because there's this huge boom in the economy where we’re building all these data centers and factories. Eventually humans can do things with their body and we can do things with our mind. There's not some secret third thing.
What should society be planning for? It should be full automation of humans. Society will also be much wealthier. Presumably there are ways to do this such that everybody is much better off than they are today. But the end state, the light at the end of the tunnel, is the full automation but plus super wealthy society with some redistribution or whatever way to figure that out. I don't know if you disagree with that characterization.
Sergey Levine 01:30:54
At some level that's a very reasonable way to look at things. But if there's one thing that I've learned about technology, it's that it rarely evolves quite the way that people expect. Sometimes the journey is just as important as the destination. It's very difficult to plan ahead for an end state. Directionally, what you said makes a lot of sense. I do think that it's very important for us collectively to think about how to structure the world around us in a way that is amenable to greater and greater automation across all sectors. But we should really think about the journey just as much as the destination, because things evolve in all sorts of unpredictable ways. We'll find automation showing up in all sorts of places, probably not the places we expect first.
The constant here that is really important is that education is really, really valuable. Education is the best buffer somebody has against the negative effects of change. If there is one single lever that we can pull collectively as a society, it's more education.
Dwarkesh Patel 01:32:04
Is that true? Moravec's paradox is that the things which are most beneficial from education for humans might be the easiest to automate because it's really easy to educate AIs. You can throw the textbooks that would take you eight years of grad school to do at them in an afternoon.
Sergey Levine 01:32:18
What education gives you is flexibility. It's less about the particular facts you know, as it is about your ability to acquire skills, acquire understanding. It has to be a good education.
Dwarkesh Patel 01:32:34
Yeah. Okay, Sergey, thank you so much for coming on the podcast. Super fascinating.
Sergey Levine 01:32:38
Yeah, this was intense. Tough questions.
