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Andrej Karpathy — “We’re summoning ghosts, not building animals”

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Andrej Karpathy — “We’re summoning ghosts, not building animals”

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1806 segments

0:48

Today I'm speaking with Andrej Karpathy. Andrej, why do you say that this will be  

0:52

the decade of agents and not the year of agents? First of all, thank you for having me here. I'm  

0:58

excited to be here. The quote you've just  mentioned, "It's the decade of agents,"  

1:03

is actually a reaction to a pre-existing quote. I'm not actually sure who said this but they were  

1:09

alluding to this being the year of agents with  respect to LLMs and how they were going to evolve. 

1:16

I was triggered by that because there's some  over-prediction going on in the industry. 

1:21

In my mind, this is more accurately  described as the decade of agents. 

1:25

We have some very early agents that  are extremely impressive and that I  

1:28

use daily—Claude and Codex and so on—but I  still feel there's so much work to be done. 

1:35

My reaction is we'll be working  with these things for a decade. 

1:38

They're going to get better,  and it's going to be wonderful. 

1:42

I was just reacting to the  timelines of the implication. 

1:46

What do you think will take a decade to  accomplish? What are the bottlenecks? 

1:51

Actually making it work. When you're talking  about an agent, or what the labs have in mind  

1:56

and maybe what I have in mind as well, you  should think of it almost like an employee or  

1:59

an intern that you would hire to work with you. For example, you work with some employees here. 

2:04

When would you prefer to have an agent like  Claude or Codex do that work? Currently,  

2:08

of course they can't. What would it  take for them to be able to do that? 

2:11

Why don't you do it today? The reason you don't do it  

2:13

today is because they just don't work. They don't have enough intelligence,  

2:17

they're not multimodal enough, they  can't do computer use and all this stuff. 

2:20

They don't do a lot of the things you've  alluded to earlier. They don't have  

2:24

continual learning. You can't just tell  them something and they'll remember it. 

2:27

They're cognitively lacking  and it's just not working. 

2:30

It will take about a decade to  work through all of those issues. 

2:32

Interesting. As a professional podcaster  and a viewer of AI from afar, it's easy  

2:42

for me to identify what's lacking: continual  learning is lacking, or multimodality is lacking. 

2:47

But I don't really have a good way  of trying to put a timeline on it. 

2:52

If somebody asks how long continual learning  will take, I have no prior about whether  

2:57

this is a project that should take 5  years, 10 years, or 50 years. Why a  

3:01

decade? Why not one year? Why not 50 years? This is where you get into a bit of my own  

3:07

intuition, and doing a bit of an extrapolation  with respect to my own experience in the field. 

3:14

I've been in AI for almost two decades. It's going to be 15 years or so, not that long. 

3:19

You had Richard Sutton here,  who was around for much longer. 

3:23

I do have about 15 years of experience of people  making predictions, of seeing how they turned out. 

3:28

Also I was in the industry for  a while, I was in research,  

3:30

and I've worked in the industry for a while. 

3:32

I have a general intuition  that I have left from that. 

3:37

I feel like the problems are tractable, they're  surmountable, but they're still difficult. 

3:43

If I just average it out, it  just feels like a decade to me. 

3:47

This is quite interesting. I want  to hear not only the history,  

3:50

but what people in the room felt was about to  happen at various different breakthrough moments. 

3:58

What were the ways in which their feelings were  either overly pessimistic or overly optimistic? 

4:03

Should we just go through each of them one by one? That's a giant question because you're talking  

4:07

about 15 years of stuff that happened. AI is so wonderful because there have been  

4:10

a number of seismic shifts where the entire  field has suddenly looked a different way. 

4:17

I've maybe lived through two or three of those. I still think there will continue to be  

4:21

some because they come with  almost surprising regularity. 

4:25

When my career began, when I started to work on  deep learning, when I became interested in deep  

4:29

learning, this was by chance of being right next  to Geoff Hinton at the University of Toronto. 

4:34

Geoff Hinton, of course, is  the godfather figure of AI. 

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He was training all these neural networks. I thought it was incredible and interesting. 

4:40

This was not the main thing that  everyone in AI was doing by far. 

4:43

This was a niche little subject on the side. That's maybe the first dramatic seismic shift  

4:49

that came with the AlexNet and so on. AlexNet reoriented everyone, and everyone  

4:54

started to train neural networks, but it  was still very per-task, per specific task. 

4:59

Maybe I have an image classifier or I have a  neural machine translator or something like that. 

5:04

People became very slowly interested in agents. People started to think, "Okay, maybe we have a  

5:10

check mark next to the visual cortex or something  like that, but what about the other parts of the  

5:14

brain, and how can we get a full agent or a  full entity that can interact in the world?" 

5:19

The Atari deep reinforcement learning shift  in 2013 or so was part of that early effort  

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of agents, in my mind, because it was an  attempt to try to get agents that not just  

5:30

perceive the world, but also take actions and  interact and get rewards from environments. 

5:34

At the time, this was Atari games. I feel that was a misstep. 

5:39

It was a misstep that even the early OpenAI that  I was a part of adopted because at that time,  

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the zeitgeist was reinforcement learning  environments, games, game playing,  

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beat games, get lots of different types of  games, and OpenAI was doing a lot of that. 

5:54

That was another prominent part of AI where maybe  for two or three or four years, everyone was doing  

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reinforcement learning on games. That was all a bit of a misstep. 

6:06

What I was trying to do at OpenAI is  I was always a bit suspicious of games  

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as being this thing that would lead to AGI. Because in my mind, you want something like  

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an accountant or something that's  interacting with the real world. 

6:17

I just didn't see how games add up to it. My project at OpenAI, for example, was within the  

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scope of the Universe project, on an agent that  was using keyboard and mouse to operate web pages. 

6:30

I really wanted to have something that  interacts with the actual digital world  

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that can do knowledge work. It just so turns out that this  

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was extremely early, way too early, so early  that we shouldn't have been working on that. 

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Because if you're just stumbling your way around  and keyboard mashing and mouse clicking and trying  

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to get rewards in these environments, your  reward is too sparse and you just won't learn. 

6:52

You're going to burn a forest  computing, and you're never  

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going to get something off the ground. What you're missing is this power of  

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representation in the neural network. For example, today people are training  

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those computer-using agents, but they're  doing it on top of a large language model. 

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You have to get the language model first,  you have to get the representations first,  

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and you have to do that by all the  pre-training and all the LLM stuff. 

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I feel maybe loosely speaking, people  kept trying to get the full thing too  

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early a few times, where people really try  to go after agents too early, I would say. 

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That was Atari and Universe  and even my own experience. 

7:26

You actually have to do some things  first before you get to those agents. 

7:30

Now the agents are a lot more competent, but maybe  we're still missing some parts of that stack. 

7:36

I would say those are the three major  buckets of what people were doing:  

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training neural nets per-tasks,  trying the first round of agents,  

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and then maybe the LLMs and seeking the  representation power of the neural networks  

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before you tack on everything else on top. Interesting. If I were to steelman the Sutton  

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perspective, it would be that humans  can just take on everything at once,  

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or even animals can take on everything at once. Animals are maybe a better example because they  

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don't even have the scaffold of language. They just get thrown out into the world,  

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and they just have to make sense  of everything without any labels. 

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The vision for AGI then should just be  something which looks at sensory data,  

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looks at the computer screen, and it just  figures out what's going on from scratch. 

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If a human were put in a similar situation and  had to be trained from scratch… This is like a  

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human growing up or an animal growing up. Why shouldn't that be the vision for AI,  

8:26

rather than this thing where we're  doing millions of years of training? 

8:29

That's a really good question. Sutton was  on your podcast and I saw the podcast and I  

8:35

had a write-up about that podcast that  gets into a bit of how I see things. 

8:41

I'm very careful to make analogies to  animals because they came about by a  

8:46

very different optimization process. Animals are evolved, and they come  

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with a huge amount of hardware that's built in. For example, my example in the post was the zebra. 

8:55

A zebra gets born, and a few minutes later  it's running around and following its mother. 

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That's an extremely complicated thing to do.  That's not reinforcement learning. That's  

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something that's baked in. Evolution obviously  has some way of encoding the weights of our  

9:08

neural nets in ATCGs, and I have no idea  how that works, but it apparently works. 

9:14

Brains just came from a very different process,  and I'm very hesitant to take inspiration from it  

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because we're not actually running that process. In my post, I said we're not building animals. 

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We're building ghosts or spirits or  whatever people want to call it, because  

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we're not doing training by evolution. We're doing training by imitation of humans  

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and the data that they've put on the Internet. You end up with these ethereal spirit entities  

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because they're fully digital  and they're mimicking humans. 

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It's a different kind of intelligence. If you imagine a space of intelligences,  

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we're starting off at a different point almost.  We're not really building animals. But it's also  

9:53

possible to make them a bit more animal-like  over time, and I think we should be doing that.  

9:58

One more point. I do feel Sutton has a very... His framework is, "We want to build animals." 

10:04

I think that would be wonderful if we can  get that to work. That would be amazing.  

10:07

If there were a single algorithm that you  can just run on the Internet and it learns  

10:13

everything, that would be incredible. I'm not sure that it exists and that's  

10:18

certainly not what animals do, because  animals have this outer loop of evolution. 

10:24

A lot of what looks like learning is  more like maturation of the brain. 

10:28

I think there's very little  reinforcement learning for animals. 

10:32

A lot of the reinforcement learning is more  like motor tasks; it's not intelligence tasks. 

10:37

So I actually kind of think humans  don’t really use RL, roughly speaking. 

10:41

Can you repeat the last sentence? A lot of that intelligence is  

10:42

not motor task…it's what, sorry? A lot of the reinforcement learning, in my  

10:45

perspective, would be things that are a lot more  motor-like, simple tasks like throwing a hoop. 

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But I don't think that humans use reinforcement  learning for a lot of intelligence tasks  

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like problem-solving and so on. That doesn't mean we shouldn't  

11:01

do that for research, but I just feel  like that's what animals do or don't. 

11:05

I'm going to take a second to digest that  because there are a lot of different ideas. 

11:09

Here’s one clarifying question I can  ask to understand the perspective. 

11:15

You suggest that evolution is doing  the kind of thing that pre-training  

11:18

does in the sense of building something  which can then understand the world. 

11:24

The difference is that evolution  has to be titrated in the case  

11:28

of humans through three gigabytes of DNA. That's very unlike the weights of a model. 

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Literally, the weights of the model are  a brain, which obviously does not exist  

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in the sperm and the egg. So it has to be grown. 

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Also, the information for every single  synapse in the brain simply cannot exist  

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in the three gigabytes that exist in the DNA. Evolution seems closer to finding the algorithm  

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which then does the lifetime learning. Now, maybe the lifetime learning is  

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not analogous to RL, to your point. Is that compatible with the thing you  

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were saying, or would you disagree with that? I think so. I would agree with you that there's  

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some miraculous compression  going on because obviously,  

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the weights of the neural net are not stored  in ATCGs. There's some dramatic compression.  

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There are some learning algorithms encoded that  take over and do some of the learning online. 

12:18

I definitely agree with you on that. I would say I'm a lot more practically minded. 

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I don't come at it from the  perspective of, let's build animals. 

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I come from it from the perspective  of, let's build useful things. 

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I have a hard hat on, and I'm just  observing that we're not going to do  

12:31

evolution, because I don't know how to do that. But it does turn out we can build these ghosts,  

12:36

spirit-like entities, by imitating internet  documents. This works. It's a way to bring you  

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up to something that has a lot of built-in  knowledge and intelligence in some way,  

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similar to maybe what evolution has done. That's why I call pre-training  

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this crappy evolution. It's the practically possible version  

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with our technology and what we have available  to us to get to a starting point where we can do  

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things like reinforcement learning and so on. Just to steelman the other perspective,  

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after doing this Sutton interview and thinking  about it a bit, he has an important point here. 

13:09

Evolution does not give us the knowledge, really. It gives us the algorithm to find the knowledge,  

13:14

and that seems different from pre-training. Perhaps the perspective is that pre-training helps  

13:19

build the kind of entity which can learn better. It teaches meta-learning, and therefore  

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it is similar to finding an algorithm. But if it's "Evolution gives us knowledge,  

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pre-training gives us knowledge,"  that analogy seems to break down. 

13:31

It's subtle and I think you're right to  push back on it, but basically the thing  

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that pre-training is doing, you're getting  the next-token predictor over the internet,  

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and you're training that into a neural net. It's doing two things that are unrelated. 

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Number one, it's picking up all  this knowledge, as I call it. 

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Number two, it's actually becoming intelligent. By observing the algorithmic patterns in the  

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internet, it boots up all these little circuits  and algorithms inside the neural net to do things  

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like in-context learning and all this stuff. You don't need or want the knowledge. 

14:00

I think that's probably holding back the neural  networks overall because it's getting them to rely  

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on the knowledge a little too much sometimes. For example, I feel agents, one thing they're  

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not very good at, is going off the data  manifold of what exists on the internet. 

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If they had less knowledge or less  memory, maybe they would be better. 

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What I think we have to do going forward—and  this would be part of the research paradigms—is  

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figure out ways to remove some of the knowledge  and to keep what I call this cognitive core. 

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It's this intelligent entity that is stripped from  knowledge but contains the algorithms and contains  

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the magic of intelligence and problem-solving  and the strategies of it and all this stuff. 

14:39

There's so much interesting stuff there. Let's  start with in-context learning. This is an  

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obvious point, but I think it's worth just  saying it explicitly and meditating on it. 

14:48

The situation in which these models seem the most  intelligent—in which I talk to them and I'm like,  

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"Wow, there's really something on the other end  that's responding to me thinking about things—is  

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if it makes a mistake it's like, "Oh wait, that's  the wrong way to think about it. I'm backing up."  

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All that is happening in context. That's where I feel like the real  

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intelligence is that you can visibly see. That in-context learning process is  

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developed by gradient descent on pre-training. It spontaneously meta-learns in-context learning,  

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but the in-context learning itself is not  gradient descent, in the same way that our  

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lifetime intelligence as humans to be able  to do things is conditioned by evolution  

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but our learning during our lifetime is  happening through some other process. 

15:30

I don't fully agree with that, but  you should continue your thought. 

15:34

Well, I'm very curious to understand  how that analogy breaks down. 

15:36

I'm hesitant to say that in-context  learning is not doing gradient descent. 

15:41

It's not doing explicit gradient descent. In-context learning is pattern completion  

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within a token window. It just turns out that there's  

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a huge amount of patterns on the internet. You're right, the model learns to complete  

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the pattern, and that's inside the weights. The weights of the neural network are trying  

15:58

to discover patterns and complete the pattern. There's some adaptation that happens inside  

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the neural network, which is magical  and just falls out from the internet  

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just because there's a lot of patterns. I will say that there have been some papers  

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that I thought were interesting that look at  the mechanisms behind in-context learning. 

16:14

I do think it's possible that in-context  learning runs a small gradient descent loop  

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internally in the layers of the neural network. I recall one paper in particular where they were  

16:22

doing linear regression using in-context learning. Your inputs into the neural network are XY pairs,  

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XY, XY, XY that happen to be on the line. Then you do X and you expect Y. 

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The neural network, when you train it  in this way, does linear regression. 

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Normally when you would run linear regression, you  have a small gradient descent optimizer that looks  

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at XY, looks at an error, calculates the gradient  of the weights and does the update a few times. 

16:50

It just turns out that when they looked at the  weights of that in-context learning algorithm,  

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they found some analogies to  gradient descent mechanics. 

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In fact, I think the paper was even stronger  because they hardcoded the weights of a neural  

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network to do gradient descent through  attention and all the internals of the  

17:10

neural network. That's just my only pushback.  Who knows how in-context learning works,  

17:14

but I think that it's probably doing a bit of some  funky gradient descent internally. I think that  

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that's possible. I was only pushing back on your  saying that it's not doing in-context learning. 

17:24

Who knows what it's doing, but it's probably maybe  doing something similar to it, but we don't know. 

17:28

So then it's worth thinking okay, if  in-context learning and pre-training  

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are both implementing something like gradient  descent, why does it feel like with in-context  

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learning we're getting to this continual  learning, real intelligence-like thing? 

17:44

Whereas you don't get the analogous feeling just  from pre-training. You could argue that. If it's  

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the same algorithm, what could be different? One way you could think about it is,  

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how much information does the model store  per information it receives from training? 

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If you look at pre-training, if  you look at Llama 3 for example,  

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I think it's trained on 15 trillion tokens. If you look at the 70B model, that would  

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be the equivalent of 0.07 bits per  token that it sees in pre-training,  

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in terms of the information in the weights  of the model compared to the tokens it reads. 

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Whereas if you look at the KV cache  and how it grows per additional token  

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in in-context learning, it's like 320 kilobytes. So that's a 35 million-fold difference in how much  

18:29

information per token is assimilated by the model. I wonder if that's relevant at all. 

18:34

I kind of agree. The way I usually put this is  that anything that happens during the training of  

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the neural network, the knowledge is only a hazy  recollection of what happened in training time. 

18:45

That's because the compression is dramatic. You're taking 15 trillion tokens and you're  

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compressing it to just your final neural  network of a few billion parameters. 

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Obviously it's a massive  amount of compression going on. 

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So I refer to it as a hazy  recollection of the internet documents. 

18:57

Whereas anything that happens in the  context window of the neural network—you're  

19:00

plugging in all the tokens and building up  all those KV cache representations—is very  

19:04

directly accessible to the neural net. So I compare the KV cache and the stuff  

19:08

that happens at test time to  more like a working memory. 

19:11

All the stuff that's in the context window is  very directly accessible to the neural net. 

19:16

There's always these almost surprising  analogies between LLMs and humans. 

19:21

I find them surprising because we're not  trying to build a human brain directly. 

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We're just finding that this  works and we're doing it. 

19:27

But I do think that anything  that's in the weights, it's a  

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hazy recollection of what you read a year ago. Anything that you give it as a context at test  

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time is directly in the working memory. That's a very powerful analogy to  

19:40

think through things. When you, for example,  

19:42

go to an LLM and you ask it about some book  and what happened in it, like Nick Lane's  

19:46

book or something like that, the LLM will often  give you some stuff which is roughly correct. 

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But if you give it the full chapter and ask it  questions, you're going to get much better results  

19:53

because it's now loaded in the  working memory of the model. 

19:56

So a very long way of saying  I agree and that's why. 

20:00

Stepping back, what is the part  about human intelligence that we  

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have most failed to replicate with these models? 

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Just a lot of it. So maybe one way to think  about it, I don't know if this is the best way,  

20:17

but I almost feel like — again, making these  analogies imperfect as they are — we've stumbled  

20:22

by with the transformer neural network,  which is extremely powerful, very general. 

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You can train transformers on audio, or  video, or text, or whatever you want,  

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and it just learns patterns and they're  very powerful, and it works really well. 

20:35

That to me almost indicates that this  is some piece of cortical tissue. 

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It's something like that, because the  cortex is famously very plastic as well. 

20:42

You can rewire parts of brains. There were the slightly gruesome experiments  

20:48

with rewiring the visual cortex to the auditory  cortex, and this animal learned fine, et cetera. 

20:54

So I think that this is cortical tissue. I think when we're doing reasoning and  

20:58

planning inside the neural networks, doing  reasoning traces for thinking models,  

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that's kind of like the prefrontal cortex. Maybe those are like little checkmarks,  

21:11

but I still think there are many brain  parts and nuclei that are not explored. 

21:15

For example, there's a basal ganglia doing a  bit of reinforcement learning when we fine-tune  

21:18

the models on reinforcement learning. But where's  the hippocampus? Not obvious what that would be. 

21:23

Some parts are probably not important. Maybe the cerebellum is not important  

21:26

to cognition, its thoughts, so  maybe we can skip some of it. 

21:29

But I still think there's, for example, the  amygdala, all the emotions and instincts. 

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There's probably a bunch of other nuclei  in the brain that are very ancient that  

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I don't think we've really replicated. I don't know that we should be pursuing the  

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building of an analog of a human brain. I'm an engineer mostly at heart. 

21:48

Maybe another way to answer the question is that  you're not going to hire this thing as an intern. 

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It's missing a lot of it because it comes with  a lot of these cognitive deficits that we all  

21:55

intuitively feel when we talk to the models. So it's not fully there yet. 

22:00

You can look at it as not all the  brain parts are checked off yet. 

22:04

This is maybe relevant to the question of thinking  about how fast these issues will be solved. 

22:10

Sometimes people will say  about continual learning,  

22:13

"Look, you could easily replicate this capability. Just as in-context learning emerged spontaneously  

22:19

as a result of pre-training, continual  learning over longer horizons will emerge  

22:24

spontaneously if the model is incentivized to  recollect information over longer horizons,  

22:30

or horizons longer than one session." So if there's some outer loop RL which has  

22:39

many sessions within that outer loop, then this  continual learning where it fine-tunes itself,  

22:46

or it writes to an external memory or  something, will just emerge spontaneously. 

22:49

Do you think things like that are plausible? I just don't have a prior over  

22:53

how plausible that is. How likely is that to happen? 

22:55

I don't know that I fully resonate with that. These models, when you boot them up and they have  

22:59

zero tokens in the window, they're always  restarting from scratch where they were. 

23:03

So I don't know in that  worldview what it looks like. 

23:09

Maybe making some analogies to humans—just because  I think it's roughly concrete and interesting to  

23:13

think through—I feel like when I'm awake, I'm  building up a context window of stuff that's  

23:17

happening during the day. But when I go to sleep,  

23:19

something magical happens where I don't  think that context window stays around. 

23:23

There's some process of distillation  into the weights of my brain. 

23:27

This happens during sleep and all this stuff. We don't have an equivalent  

23:30

of that in large language models. That's to me more adjacent to when you talk  

23:35

about continual learning and so on as absent. These models don't really have a distillation  

23:40

phase of taking what happened, analyzing it  obsessively, thinking through it, doing some  

23:47

synthetic data generation process and distilling  it back into the weights, and maybe having  

23:51

a specific neural net per person. Maybe it's  a LoRA. It's not a full-weight neural network. 

24:01

It's just some small sparse subset  of the weights that are changed. 

24:05

But we do want to create ways of creating  these individuals that have very long context. 

24:10

It's not only remaining in the context window  because the context windows grow very, very long. 

24:14

Maybe we have some very elaborate,  sparse attention over it. 

24:17

But I still think that humans obviously have some  process for distilling some of that knowledge  

24:22

into the weights. We're missing it. I do also  think that humans have some very elaborate,  

24:27

sparse attention scheme, which I think  we're starting to see some early hints of. 

24:33

DeepSeek v3.2 just came out and I saw that they  have sparse attention as an example, and this is  

24:38

one way to have very, very long context windows. So I feel like we are redoing a lot of the  

24:44

cognitive tricks that evolution came up  with through a very different process. 

24:47

But we're going to converge on a  similar architecture cognitively. 

24:51

In 10 years, do you think it'll still be something  like a transformer, but with much more modified  

24:55

attention and more sparse MLPs and so forth? The way I like to think about it is  

25:00

translation invariance in time. So 10 years ago, where were we? 2015. 

25:05

In 2015, we had convolutional neural networks  primarily, residual networks just came out. 

25:10

So remarkably similar, I guess, but quite a  bit different still. The transformer was not  

25:14

around. All these more modern tweaks  on the transformer were not around. 

25:21

Maybe some of the things that we can bet on, I  think in 10 years by translational equivariance,  

25:27

is that we're still training giant neural  networks with a forward backward pass and  

25:31

update through gradient descent,  but maybe it looks a bit different,  

25:36

and it's just that everything is much bigger. Recently I went back all the way to 1989 which  

25:42

was a fun exercise for me, a few years ago,  because I was reproducing Yann LeCun's 1989  

25:48

convolutional network, which was the first neural  network I'm aware of trained via gradient descent,  

25:52

like modern neural network trained  gradient descent on digit recognition. 

25:57

I was just interested in  how I could modernize this. 

26:00

How much of this is algorithms? How much of this is data? 

26:01

How much of this progress is compute and systems? I was able to very quickly halve the learning  

26:06

just by time traveling by 33 years. So if I time travel by algorithms 33 years,  

26:13

I could adjust what Yann LeCun did  in 1989, and I could halve the error. 

26:18

But to get further gains, I  had to add a lot more data,  

26:21

I had to 10x the training set, and then I  had to add more computational optimizations. 

26:25

I had to train for much longer with dropout  and other regularization techniques. 

26:30

So all these things have  to improve simultaneously. 

26:35

We're probably going to have a lot more  data, we're probably going to have a lot  

26:37

better hardware, probably going to have a lot  better kernels and software, we're probably  

26:40

going to have better algorithms. All of those, it's almost like  

26:43

no one of them is winning too much. All of them are surprisingly equal. 

26:48

This has been the trend for a while. So to answer your question, I expect differences  

26:54

algorithmically to what's happening today. But I do also expect that some of the  

26:58

things that have stuck around for a very  long time will probably still be there. 

27:01

It's probably still a giant neural network trained  with gradient descent. That would be my guess. 

27:05

It's surprising that all of those things  together only halved the error, 30 years  

27:13

of progress…. Maybe half is a lot. Because if  you halve the error, that actually means that… 

27:18

Half is a lot. But I guess what was shocking to me  is everything needs to improve across the board:  

27:24

architecture, optimizer, loss function. It also has improved across the board forever. 

27:28

So I expect all those  changes to be alive and well. 

27:31

Yeah. I was about to ask you a very  similar question about nanochat. 

27:35

Since you just coded it up recently,  every single step in the process of  

27:40

building a chatbot is fresh in your RAM. I'm curious if you had similar thoughts about,  

27:46

"Oh, there was no one thing that was  relevant to going from GPT-2 to nanochat." 

27:52

What are some surprising  takeaways from the experience? 

27:55

Of building nanochat? So nanochat  is a repository I released. 

27:59

Was it yesterday or the day  before? I can't remember. 

28:03

We can see the sleep  deprivation that went into the… 

28:09

It's trying to be the simplest complete  repository that covers the whole pipeline  

28:12

end-to-end of building a ChatGPT clone. So you have all of the steps, not just  

28:18

any individual step, which is a bunch. I worked on all the individual steps  

28:22

in the past and released small pieces  of code that show you how that's done  

28:25

in an algorithmic sense, in simple code. But this handles the entire pipeline. 

28:32

In terms of learning, I don't  know that I necessarily found  

28:36

something that I learned from it. I already had in my mind how you build it. 

28:40

This is just the process of mechanically building  it and making it clean enough so that people can  

28:48

learn from it and that they find it useful. What is the best way for somebody  

28:53

to learn from it? Is it to just delete  

28:54

all the code and try to reimplement from  scratch, try to add modifications to it? 

28:59

That's a great question. Basically  it's about 8,000 lines of code  

29:03

that takes you through the entire pipeline. I would probably put it on the right monitor. 

29:07

If you have two monitors, you put it on the right. You want to build it from scratch,  

29:11

you build it from the start. You're not allowed to copy-paste, you're allowed  

29:14

to reference, you're not allowed to copy-paste. Maybe that's how I would do it. 

29:18

But I also think the repository  by itself is a pretty large beast. 

29:23

When you write this code, you don't go from top  to bottom, you go from chunks and you grow the  

29:27

chunks, and that information is absent. You wouldn't know where to start. 

29:31

So it's not just a final repository that's  needed, it's the building of the repository,  

29:35

which is a complicated chunk-growing process. So that part is not there yet. 

29:40

I would love to add that probably later this week. It's probably a video or something like that. 

29:49

Roughly speaking, that's what I would try to do. Build the stuff yourself, but don't allow  

29:53

yourself copy-paste. I do think that  

29:55

there's two types of knowledge, almost. There's the high-level surface knowledge, but when  

29:59

you build something from scratch, you're forced to  come to terms with what you don't understand and  

30:04

you don't know that you don't understand it. It always leads to a deeper understanding. 

30:09

It's the only way to build. If I can't build it, I don't understand it. 

30:13

That’s a Feynman quote, I believe. I 100% have always believed this very  

30:19

strongly, because there are all these micro  things that are just not properly arranged  

30:23

and you don't really have the knowledge. You just think you have the knowledge. 

30:25

So don't write blog posts, don't  do slides, don't do any of that. 

30:28

Build the code, arrange it, get it to work. It's the only way to go. Otherwise,  

30:31

you're missing knowledge. You tweeted out that coding models  

30:35

were of very little help to you in assembling  this repository. I'm curious why that was. 

30:43

I guess I built the repository over  a period of a bit more than a month. 

30:46

I would say there are three major classes  of how people interact with code right now. 

30:50

Some people completely reject all of LLMs  and they are just writing by scratch. 

30:54

This is probably not the  right thing to do anymore. 

30:58

The intermediate part, which is where I am, is  you still write a lot of things from scratch,  

31:02

but you use the autocomplete that's  available now from these models. 

31:06

So when you start writing out a little  piece of it, it will autocomplete for  

31:10

you and you can just tap through. Most of the time it's correct,  

31:12

sometimes it's not, and you edit it. But you're still very much the  

31:16

architect of what you're writing. Then there's the vibe coding: "Hi,  

31:21

please implement this or that," enter, and then  let the model do it. That's the agents. I do feel  

31:28

like the agents work in very specific settings,  and I would use them in specific settings. 

31:33

But these are all tools available to you  and you have to learn what they're good at,  

31:37

what they're not good at, and when to use them. So the agents are pretty good, for example,  

31:40

if you're doing boilerplate stuff. Boilerplate code that's just  

31:44

copy-paste stuff, they're very good at that. They're very good at stuff that occurs very often  

31:48

on the Internet because there are lots of examples  of it in the training sets of these models. 

31:55

There are features of things where  the models will do very well. 

31:58

I would say nanochat is not an example of  those because it's a fairly unique repository. 

32:03

There's not that much code in the way that  I've structured it. It's not boilerplate code.  

32:08

It's intellectually intense code almost, and  everything has to be very precisely arranged. 

32:13

The models have so many cognitive deficits. One example, they kept misunderstanding the code  

32:22

because they have too much memory from  all the typical ways of doing things on  

32:26

the Internet that I just wasn't adopting. The models, for example—I don't know if I  

32:31

want to get into the full details—but they kept  thinking I'm writing normal code, and I'm not. 

32:36

Maybe one example? You have eight GPUs  

32:41

that are all doing forward, backwards. The way to synchronize gradients between  

32:44

them is to use a Distributed Data Parallel  container of PyTorch, which automatically  

32:49

as you're doing the backward, it will start  communicating and synchronizing gradients. 

32:52

I didn't use DDP because I didn't want  to use it, because it's not necessary. 

32:56

I threw it out and wrote my own synchronization  routine that's inside the step of the optimizer. 

33:02

The models were trying to get me to  use the DDP container. They were very  

33:06

concerned. This gets way too technical,  but I wasn't using that container because  

33:11

I don't need it and I have a custom  implementation of something like it. 

33:14

They just couldn't internalize  that you had your own. 

33:16

They couldn't get past that. They kept trying to  mess up the style. They're way too over-defensive.  

33:23

They make all these try-catch statements. They keep trying to make a production code base,  

33:27

and I have a bunch of assumptions  in my code, and it's okay. 

33:31

I don't need all this extra stuff in there. So I feel like they're bloating the code base,  

33:36

bloating the complexity, they keep  misunderstanding, they're using  

33:38

deprecated APIs a bunch of times. It's a total  mess. It's just not net useful. I can go in,  

33:46

I can clean it up, but it's not net useful. I also feel like it's annoying to have to  

33:50

type out what I want in English  because it's too much typing. 

33:54

If I just navigate to the part of the code that I  want, and I go where I know the code has to appear  

33:58

and I start typing out the first few letters,  autocomplete gets it and just gives you the code. 

34:03

This is a very high information  bandwidth to specify what you want. 

34:07

You point to the code where you want  it, you type out the first few pieces,  

34:10

and the model will complete it. So what I mean is, these models  

34:15

are good in certain parts of the stack. There are two examples where I use the  

34:22

models that I think are illustrative. One was when I generated the report. 

34:26

That's more boilerplate-y, so I  partially vibe-coded some of that stuff. 

34:30

That was fine because it's not  mission-critical stuff, and it works fine. 

34:34

The other part is when I was  rewriting the tokenizer in Rust. 

34:37

I'm not as good at Rust  because I'm fairly new to Rust. 

34:41

So there's a bit of vibe coding going on  when I was writing some of the Rust code. 

34:45

But I had a Python implementation that I  fully understand, and I'm just making sure  

34:49

I'm making a more efficient version of it, and  I have tests so I feel safer doing that stuff. 

34:56

They increase accessibility to languages or  paradigms that you might not be as familiar with. 

35:02

I think they're very helpful there as well. There's a ton of Rust code out there,  

35:06

the models are pretty good at it. I happen to not know that much about it,  

35:09

so the models are very useful there. The reason this question is so interesting  

35:12

is because the main story people  have about AI exploding and getting  

35:19

to superintelligence pretty rapidly is AI  automating AI engineering and AI research. 

35:25

They'll look at the fact that you can have  Claude Code and make entire applications,  

35:27

CRUD applications, from scratch and think, "If  you had this same capability inside of OpenAI  

35:32

and DeepMind and everything, just imagine  a thousand of you or a million of you in  

35:38

parallel, finding little architectural tweaks." It's quite interesting to hear you say that this  

35:43

is the thing they're asymmetrically worse at. It's quite relevant to forecasting whether  

35:48

the AI 2027-type explosion is  likely to happen anytime soon. 

35:53

That's a good way of putting it, and you're  getting at why my timelines are a bit longer.  

35:58

You're right. They're not very good at code  that has never been written before, maybe it's  

36:04

one way to put it, which is what we're trying  to achieve when we're building these models. 

36:07

Very naive question, but the architectural  tweaks that you're adding to nanochat,  

36:14

they're in a paper somewhere, right? They might even be in a repo somewhere. 

36:20

Is it surprising that they aren't able to  integrate that into whenever you're like,  

36:25

"Add RoPE embeddings" or something,  they do that in the wrong way? 

36:29

It's tough. They know, but they don't fully know. They don't know how to fully integrate it into  

36:34

the repo and your style and your code and  your place, and some of the custom things  

36:37

that you're doing and how it fits with  all the assumptions of the repository. 

36:42

They do have some knowledge, but they  haven't gotten to the place where they  

36:46

can integrate it and make sense of it. A lot of the stuff continues to improve. 

36:54

Currently, the state-of-the-art  model that I go to is the GPT-5 Pro,  

36:57

and that's a very powerful model. If I have 20 minutes,  

37:01

I will copy-paste my entire repo and I go to  GPT-5 Pro, the oracle, for some questions. 

37:06

Often it's not too bad and surprisingly  good compared to what existed a year ago. 

37:11

Overall, the models are not there. I feel like the industry is making too  

37:20

big of a jump and is trying to pretend like this  is amazing, and it's not. It's slop. They're not  

37:27

coming to terms with it, and maybe they're  trying to fundraise or something like that. 

37:29

I'm not sure what's going on, but we're  at this intermediate stage. The models are  

37:33

amazing. They still need a lot of work. For now, autocomplete is my sweet spot. 

37:38

But sometimes, for some types of  code, I will go to an LLM agent. 

37:43

Here's another reason this is really interesting. Through the history of programming, there have  

37:48

been many productivity improvements—compilers,  linting, better programming languages—which  

37:55

have increased programmer productivity  but have not led to an explosion. 

38:00

That sounds very much like the  autocomplete tab, and this other  

38:04

category is just automation of the programmer. It's interesting you're seeing more in the  

38:09

category of the historical analogies  of better compilers or something. 

38:13

Maybe this gets to one other thought. I have a hard time differentiating where  

38:19

AI begins and stops because I see  AI as fundamentally an extension of  

38:23

computing in a pretty fundamental way. I see a continuum of this recursive  

38:28

self-improvement or speeding up programmers  all the way from the beginning: code editors,  

38:37

syntax highlighting, or checking even of  the types, like data type checking—all  

38:44

these tools that we've built for  each other. Even search engines.  

38:48

Why aren't search engines part of AI? Ranking  is AI. At some point, Google, even early on,  

38:55

was thinking of themselves as an AI company doing  Google Search engine, which is totally fair. 

38:59

I see it as a lot more of a continuum than other  people do, and it's hard for me to draw the line. 

39:04

I feel like we're now getting a much  better autocomplete, and now we're also  

39:07

getting some agents which are these loopy  things, but they go off-rails sometimes. 

39:13

What's going on is that the human is progressively  doing a bit less and less of the low-level stuff. 

39:18

We're not writing the assembly  code because we have compilers. 

39:20

Compilers will take my high-level  language in C and write the assembly code. 

39:23

We're abstracting ourselves very, very slowly. There's this what I call "autonomy slider," where  

39:28

more and more stuff is automated—of the stuff that  can be automated at any point in time—and we're  

39:32

doing a bit less and less and raising ourselves  in the layer of abstraction over the automation. 

40:53

Let's talk about RL a bit. You tweeted some very  

40:56

interesting things about this. Conceptually, how should we think about  

41:00

the way that humans are able to build a rich world  model just from interacting with our environment,  

41:07

and in ways that seem almost irrespective of  the final reward at the end of the episode? 

41:13

If somebody is starting a business, and at  the end of 10 years, she finds out whether  

41:17

the business succeeded or failed, we say that  she's earned a bunch of wisdom and experience. 

41:22

But it's not because the log probs of every  single thing that happened over the last 10  

41:25

years are up-weighted or down-weighted. Something much more deliberate and  

41:29

rich is happening. What is the ML analogy, and how does that  

41:33

compare to what we're doing with LLMs right now? Maybe the way I would put it is that humans don't  

41:36

use reinforcement learning, as I said. I think they do something different. 

41:42

Reinforcement learning is a lot worse than I  think the average person thinks. Reinforcement  

41:48

learning is terrible. It just so happens  that everything that we had before it is  

41:53

much worse because previously we were just  imitating people, so it has all these issues. 

41:59

In reinforcement learning, say you're solving  a math problem, because it's very simple. 

42:04

You're given a math problem and  you're trying to find the solution. 

42:08

In reinforcement learning, you will  try lots of things in parallel first. 

42:13

You're given a problem, you try hundreds of  different attempts. These attempts can be complex.  

42:18

They can be like, "Oh, let me try this, let me try  that, this didn't work, that didn't work," etc. 

42:22

Then maybe you get an answer. Now you check the back of the book and you see,  

42:25

"Okay, the correct answer is this." You can see that this one, this one,  

42:30

and that one got the correct answer,  but these other 97 of them didn't. 

42:33

Literally what reinforcement learning does is it  goes to the ones that worked really well and every  

42:37

single thing you did along the way, every single  token gets upweighted like, "Do more of this." 

42:42

The problem with that is people will say  that your estimator has high variance,  

42:46

but it's just noisy. It's noisy. It almost assumes  that every single little piece of the solution  

42:53

that you made that arrived at the right answer  was the correct thing to do, which is not true. 

42:56

You may have gone down the wrong alleys  until you arrived at the right solution. 

43:00

Every single one of those incorrect things you  did, as long as you got to the correct solution,  

43:04

will be upweighted as, "Do more of this."  It's terrible. It's noise. You've done all  

43:08

this work only to find, at the end, you get a  single number of like, "Oh, you did correct." 

43:14

Based on that, you weigh that entire  trajectory as like, upweight or downweight. 

43:19

The way I like to put it is you're  sucking supervision through a straw. 

43:22

You've done all this work that  could be a minute of rollout,  

43:24

and you're sucking the bits of supervision of the  final reward signal through a straw and you're  

43:33

broadcasting that across the entire trajectory  and using that to upweight or downweight that  

43:37

trajectory. It's just stupid and  crazy. A human would never do this. 

43:39

Number one, a human would  never do hundreds of rollouts. 

43:43

Number two, when a person finds a solution,  they will have a pretty complicated process  

43:47

of review of, "Okay, I think these parts I  did well, these parts I did not do that well. 

43:51

I should probably do this or that."  They think through things. There's  

43:55

nothing in current LLMs that does this.  There's no equivalent of it. But I do see  

44:00

papers popping out that are trying to do this  because it's obvious to everyone in the field. 

44:05

The first imitation learning, by the way, was  extremely surprising and miraculous and amazing,  

44:09

that we can fine-tune by imitation on humans.  That was incredible. Because in the beginning,  

44:14

all we had was base models. Base models  are autocomplete. It wasn't obvious to  

44:18

me at the time, and I had to learn this. The paper that blew my mind was InstructGPT,  

44:24

because it pointed out that you can take  the pretrained model, which is autocomplete,  

44:28

and if you just fine-tune it on text that looks  like conversations, the model will very rapidly  

44:32

adapt to become very conversational, and it  keeps all the knowledge from pre-training. 

44:36

This blew my mind because I didn't understand  that stylistically, it can adjust so quickly  

44:41

and become an assistant to a user through just  a few loops of fine-tuning on that kind of data. 

44:46

It was very miraculous to me that that worked.  So incredible. That was two to three years of  

44:51

work. Now came RL. And RL allows you to do a bit  better than just imitation learning because you  

44:58

can have these reward functions and you  can hill-climb on the reward functions. 

45:02

Some problems have just correct answers, you  can hill-climb on that without getting expert  

45:06

trajectories to imitate. So that's amazing. The  model can also discover solutions that a human  

45:10

might never come up with. This is incredible.  Yet, it's still stupid. We need more. I saw a  

45:19

paper from Google yesterday that tried to  have this reflect & review idea in mind. 

45:25

Was it the memory bank paper or something? I don't  know. I've seen a few papers along these lines. 

45:30

So I expect there to be some major update to how  we do algorithms for LLMs coming in that realm. 

45:37

I think we need three or four or  five more, something like that. 

45:42

You're so good at coming up with evocative  phrases. "Sucking supervision through a  

45:47

straw." It's so good. You're saying the problem  with outcome-based reward is that you have this  

45:56

huge trajectory, and then at the end, you're  trying to learn every single possible thing  

46:01

about what you should do and what you should  learn about the world from that one final bit. 

46:07

Given the fact that this is obvious, why hasn't  process-based supervision as an alternative been  

46:11

a successful way to make models more capable? What has been preventing us from using  

46:15

this alternative paradigm? Process-based supervision just  

46:18

refers to the fact that we're not going to  have a reward function only at the very end. 

46:21

After you've done 10 minutes of work, I'm not  going to tell you you did well or not well. 

46:24

I'm going to tell you at every single  step of the way how well you're doing. 

46:28

The reason we don't have that is  it's tricky how you do that properly. 

46:32

You have partial solutions and you  don't know how to assign credit. 

46:34

So when you get the right answer, it's just  an equality match to the answer. It’s very  

46:39

simple to implement. If you're doing process  supervision, how do you assign in an automatable  

46:44

way, a partial credit assignment? It's not obvious how you do it. 

46:47

Lots of labs are trying to  do it with these LLM judges. 

46:50

You get LLMs to try to do it. You prompt an LLM, "Hey,  

46:53

look at a partial solution of a student. How well do you think they're doing if the  

46:56

answer is this?" and they try to tune the prompt. The reason that this is tricky is quite subtle. 

47:02

It's the fact that anytime you use an LLM to  assign a reward, those LLMs are giant things  

47:07

with billions of parameters, and they're gameable. If you're reinforcement learning with respect to  

47:11

them, you will find adversarial examples  for your LLM judges, almost guaranteed. 

47:15

So you can't do this for too long. You do maybe 10 steps or 20 steps, and maybe  

47:18

it will work, but you can't do 100 or 1,000. I understand it's not obvious, but basically  

47:25

the model will find little cracks. It will find all these spurious  

47:30

things in the nooks and crannies of the  giant model and find a way to cheat it. 

47:34

One example that's prominently in my mind, this  was probably public, if you're using an LLM judge  

47:42

for a reward, you just give it a solution from a  student and ask it if the student did well or not. 

47:47

We were training with  reinforcement learning against  

47:49

that reward function, and it worked really well. Then, suddenly, the reward became extremely large. 

47:55

It was a massive jump, and it did perfect. You're looking at it like, "Wow, this means  

47:59

the student is perfect in all these problems.  It's fully solved math." But when you look at  

48:05

the completions that you're getting from  the model, they are complete nonsense. 

48:08

They start out okay, and then  they change to "dhdhdhdh." 

48:11

It's just like, "Oh, okay, let's take two plus  three and we do this and this, and then dhdhdhdh." 

48:15

You're looking at it, and  it's like, this is crazy. 

48:17

How is it getting a reward of one or 100%? You look at the LLM judge, and it turns out  

48:21

that "dhdhdhdh" is an adversarial example for  the model, and it assigns 100% probability to it. 

48:27

It's just because this is an  out-of-sample example to the LLM. 

48:30

It's never seen it during training,  and you're in pure generalization land. 

48:34

It's never seen it during training, and in  the pure generalization land, you can find  

48:37

these examples that break it. You're basically training  

48:42

the LLM to be a prompt injection model. Not even that. Prompt injection is way too fancy. 

48:46

You're finding adversarial  examples, as they're called. 

48:48

These are nonsensical solutions that are obviously  wrong, but the model thinks they are amazing. 

48:55

To the extent you think this is the  bottleneck to making RL more functional,  

48:59

then that will require making LLMs better judges,  if you want to do this in an automated way. 

49:05

Is it just going to be some sort  of GAN-like approach where you  

49:07

have to train models to be more robust? The labs are probably doing all that. 

49:11

The obvious thing is, "dhdhdhdh"  should not get 100% reward. 

49:14

Okay, well, take "dhdhdhdh," put it  in the training set of the LLM judge,  

49:17

and say this is not 100%, this is 0%. You can do this, but every time you do  

49:21

this, you get a new LLM, and it  still has adversarial examples. 

49:24

There's an infinity of adversarial examples. Probably if you iterate this a few times, it'll  

49:29

probably be harder and harder to find adversarial  examples, but I'm not 100% sure because this thing  

49:32

has a trillion parameters or whatnot. I bet you the labs are trying. 

49:41

I still think we need other ideas. Interesting. Do you have some shape  

49:46

of what the other idea could be? This idea of a review solution  

49:54

encompassing synthetic examples such that  when you train on them, you get better,  

49:58

and meta-learn it in some way. I think there are some papers  

50:00

that I'm starting to see pop out. I am only at a stage of reading abstracts  

50:04

because a lot of these papers are just ideas. Someone has to make it work on a frontier  

50:08

LLM lab scale in full generality  because when you see these papers,  

50:13

they pop up, and it's just a bit noisy. They're cool ideas, but I haven't seen  

50:17

anyone convincingly show that this is possible. That said, the LLM labs are fairly closed,  

50:23

so who knows what they're doing now. I can conceptualize how you would be able  

50:33

to train on synthetic examples or synthetic  problems that you have made for yourself. 

50:36

But there seems to be another thing humans  do—maybe sleep is this, maybe daydreaming is  

50:40

this—which is not necessarily to come up  with fake problems, but just to reflect. 

50:47

I'm not sure what the ML analogy is for  daydreaming or sleeping, or just reflecting. 

50:51

I haven't come up with a new problem. Obviously, the very basic analogy would just  

50:54

be fine-tuning on reflection bits, but I feel like  in practice that probably wouldn't work that well. 

51:00

Do you have some take on what  the analogy of this thing is? 

51:05

I do think that we're missing some aspects there. As an example, let’s take reading a book. 

51:11

Currently when LLMs are reading a book, what that  means is we stretch out the sequence of text,  

51:15

and the model is predicting the next token,  and it's getting some knowledge from that. 

51:19

That's not really what humans do. When you're reading a book,  

51:21

I don't even feel like the book is exposition  I'm supposed to be attending to and training on. 

51:25

The book is a set of prompts for  me to do synthetic data generation,  

51:30

or for you to get to a book club  and talk about it with your friends. 

51:33

It's by manipulating that information  that you actually gain that knowledge. 

51:37

We have no equivalent of that with LLMs. They  don't really do that. I'd love to see during  

51:42

pre-training some stage that thinks through  the material and tries to reconcile it with  

51:46

what it already knows, and thinks through it  for some amount of time and gets that to work. 

51:52

There's no equivalence of any of this.  This is all research. There are some  

51:54

subtle—very subtle that I think are very hard  to understand—reasons why it's not trivial. 

51:59

If I can just describe one: why can't we  just synthetically generate and train on it? 

52:04

Because every synthetic example, if  I just give synthetic generation of  

52:07

the model thinking about a book, you look  at it and you're like, "This looks great. 

52:10

Why can't I train on it?" You could try, but the model  

52:12

will get much worse if you continue trying. That's because all of the samples you get  

52:17

from models are silently collapsed. Silently—it is not obvious if you look  

52:21

at any individual example of it—they occupy  a very tiny manifold of the possible space of  

52:27

thoughts about content. The LLMs, when they come off,  

52:30

they're what we call "collapsed." They have a collapsed data distribution. 

52:34

One easy way to see it is to go to  ChatGPT and ask it, "Tell me a joke." 

52:38

It only has like three jokes. It's not giving you the whole breadth  

52:41

of possible jokes. It knows like three jokes.  They're silently collapsed. You're not getting  

52:47

the richness and the diversity and the entropy  from these models as you would get from humans. 

52:52

Humans are a lot noisier, but  at least they're not biased,  

52:56

in a statistical sense. They're not silently  collapsed. They maintain a huge amount of entropy. 

53:00

So how do you get synthetic data generation to  work despite the collapse and while maintaining  

53:05

the entropy? That’s a research problem. Just to make sure I understood, the reason  

53:09

that the collapse is relevant to synthetic data  generation is because you want to be able to  

53:13

come up with synthetic problems or reflections  which are not already in your data distribution? 

53:20

I guess what I'm saying is, say we have a chapter  of a book and I ask an LLM to think about it,  

53:26

it will give you something  that looks very reasonable. 

53:28

But if I ask it 10 times, you'll  notice that all of them are the same. 

53:31

You can't just keep scaling "reflection"  on the same amount of prompt information  

53:39

and then get returns from that. Any individual sample will look okay,  

53:43

but the distribution of it is quite terrible. It's quite terrible in such a way that if  

53:47

you continue training on too much of  your own stuff, you actually collapse. 

53:50

I think that there's possibly  no fundamental solution to this. 

53:54

I also think humans collapse over time.  These analogies are surprisingly good.  

54:00

Humans collapse during the course of their lives. This is why children, they haven't overfit yet. 

54:06

They will say stuff that will shock you  because you can see where they're coming from,  

54:09

but it's just not the thing people say,  because they're not yet collapsed. But we're  

54:14

collapsed. We end up revisiting the same thoughts. We end up saying more and more of the same stuff,  

54:20

and the learning rates go down, and  the collapse continues to get worse,  

54:24

and then everything deteriorates. Have you seen this super interesting  

54:28

paper that dreaming is a way of preventing  this kind of overfitting and collapse? 

54:34

The reason dreaming is evolutionary adaptive  is to put you in weird situations that are  

54:41

very unlike your day-to-day reality, so  as to prevent this kind of overfitting. 

54:44

It's an interesting idea. I do think  that when you're generating things  

54:48

in your head and then you're attending to  it, you're training on your own samples,  

54:51

you're training on your synthetic data. If you do it for too long,  

54:53

you go off-rails and you collapse way too much. You always have to seek entropy in your life. 

55:01

Talking to other people is a great  source of entropy, and things like that. 

55:05

So maybe the brain has also built some internal  mechanisms for increasing the amount of entropy  

55:11

in that process. That's an interesting idea. This is a very ill-formed thought so I’ll  

55:16

just put it out and let you react to it. The best learners that we are aware of,  

55:20

which are children, are extremely  bad at recollecting information. 

55:25

In fact, at the very earliest stages of  childhood, you will forget everything. 

55:29

You're just an amnesiac about everything  that happens before a certain year date. 

55:32

But you're extremely good at picking up  new languages and learning from the world. 

55:36

Maybe there's some element of being  able to see the forest for the trees. 

55:38

Whereas if you compare it to the opposite end  of the spectrum, you have LLM pre-training,  

55:44

where these models will literally be  able to regurgitate word-for-word what  

55:47

is the next thing in a Wikipedia page. But their ability to learn abstract  

55:52

concepts really quickly, the way  a child can, is much more limited. 

55:55

Then adults are somewhere in between, where  they don't have the flexibility of childhood  

55:59

learning, but they can memorize facts and  information in a way that is harder for kids. 

56:05

I don't know if there's something  interesting about that spectrum. 

56:08

I think there's something very  interesting about that, 100%. 

56:10

I do think that humans have a lot more of  an element, compared to LLMs, of seeing  

56:16

the forest for the trees. We're not actually that good  

56:19

at memorization, which is actually a feature. Because we're not that good at memorization, we're  

56:25

forced to find patterns in a more general sense. LLMs in comparison are extremely good  

56:33

at memorization. They will recite  

56:35

passages from all these training sources. You can give them completely nonsensical data. 

56:41

You can hash some amount of text or something  like that, you get a completely random sequence. 

56:44

If you train on it, even just for a single  iteration or two, it can suddenly regurgitate  

56:48

the entire thing. It will memorize it.  There's no way a person can read a single  

56:51

sequence of random numbers and recite it to you. That's a feature, not a bug, because it forces  

56:58

you to only learn the generalizable components. Whereas LLMs are distracted by all the memory  

57:03

that they have of the pre-training  documents, and it's probably very  

57:06

distracting to them in a certain sense. So that's why when I talk about the  

57:10

cognitive core, I want to remove the  memory, which is what we talked about. 

57:13

I'd love to have them have less memory  so that they have to look things up,  

57:17

and they only maintain the algorithms for  thought, and the idea of an experiment,  

57:22

and all this cognitive glue of acting. And this is also relevant to preventing  

57:28

model collapse? Let me think. I'm  

57:35

not sure. It's almost like a separate axis. The models are way too good at memorization,  

57:40

and somehow we should remove that. People are much worse, but it's a good thing. 

57:46

What is a solution to model collapse? There are very naive things you could attempt. 

57:52

The distribution over logits  should be wider or something. 

57:55

There are many naive things you could try. What ends up being the problem  

57:58

with the naive approaches? That's a great question. You can imagine having  

58:02

a regularization for entropy and things like that. I guess they just don't work as well empirically  

58:06

because right now the models are collapsed. But I will say most of the tasks that we  

58:13

want from them don't actually demand diversity. That’s probably the answer to what's going on. 

58:20

The frontier labs are trying  to make the models useful. 

58:22

I feel like the diversity of  the outputs is not so much... 

58:26

Number one, it's much harder to work with and  evaluate and all this stuff, but maybe it's not  

58:29

what's capturing most of the value. In fact, it's actively penalized.  

58:34

If you're super creative in RL, it's not good. Yeah. Or maybe if you're doing a lot of writing,  

58:39

help from LLMs and stuff like that, it's probably  bad because the models will silently give  

58:42

you all the same stuff. They won't explore lots  

58:48

of different ways of answering a question. Maybe this diversity, not as many applications  

58:56

need it so the models don't have it. But then it's a problem at  

58:58

synthetic data generation time, et cetera. So we're shooting ourselves in the foot by not  

59:01

allowing this entropy to maintain in the model. Possibly the labs should try harder. 

59:06

I think you hinted that it's a very  fundamental problem, it won't be easy  

59:11

to solve. What's your intuition for that? I don't know if it's super fundamental. 

59:17

I don't know if I intended to say that. I do think that I haven't done these experiments,  

59:23

but I do think that you could probably  regularize the entropy to be higher. 

59:26

So you're encouraging the model to give you more  and more solutions, but you don't want it to  

59:31

start deviating too much from the training data. It's going to start making up its own language. 

59:34

It's going to start using words that are  extremely rare, so it's going to drift too  

59:38

much from the distribution. So I think controlling  

59:41

the distribution is just tricky. It's probably not trivial in that sense. 

59:47

How many bits should the optimal core  of intelligence end up being if you  

59:54

just had to make a guess? The thing we put on the  

59:56

von Neumann probes, how big does it have to be? It's really interesting in the history of the  

60:01

field because at one point everything was  very scaling-pilled in terms of like, "Oh,  

60:05

we're gonna make much bigger models,  trillions of parameter models." 

60:08

What the models have done in size  is they've gone up and now they've  

60:14

come down. State-of-the-art models are smaller.  Even then, I think they memorized way too much. 

60:20

So I had a prediction a while back that I almost  feel like we can get cognitive cores that are  

60:24

very good at even a billion parameters. If you talk to a billion parameter model,  

60:30

I think in 20 years, you can have  a very productive conversation. 

60:34

It thinks and it's a lot more like a human. But if you ask it some factual question, it might  

60:39

have to look it up, but it knows that it doesn't  know and it might have to look it up and it will  

60:42

just do all the reasonable things. That's surprising that you think  

60:44

it'll take a billion parameters. Because already we have billion  

60:47

parameter models or a couple billion  parameter models that are very intelligent. 

60:51

Well, state-of-the-art models  are like a trillion parameters. 

60:53

But they remember so much stuff. Yeah, but I'm surprised that in 10 years,  

60:58

given the pace… We have gpt-oss-20b. That's way better than GPT-4 original,  

61:07

which was a trillion plus parameters. Given that trend, I'm surprised you  

61:11

think in 10 years the cognitive  core is still a billion parameters. 

61:15

I'm surprised you're not like, "Oh it's  gonna be like tens of millions or millions." 

61:22

Here's the issue, the training data is  the internet, which is really terrible. 

61:26

There's a huge amount of gains to be  made because the internet is terrible. 

61:29

Even the internet, when you and I think of  the internet, you're thinking of like The  

61:32

Wall Street Journal. That's not what this  is. When you're looking at a pre-training  

61:36

dataset in the frontier lab and you look at a  random internet document, it's total garbage. 

61:40

I don't even know how this works at all. It's some like stock tickers, symbols,  

61:46

it's a huge amount of slop and garbage  from like all the corners of the internet. 

61:50

It's not like your Wall Street Journal  article, that's extremely rare. 

61:53

So because the internet is so terrible, we have  to build really big models to compress all that. 

62:00

Most of that compression is memory  work instead of cognitive work. 

62:04

But what we really want is the  cognitive part, delete the memory. 

62:08

I guess what I'm saying is that we need  intelligent models to help us refine even  

62:12

the pre-training set to just narrow  it down to the cognitive components. 

62:15

Then I think you get away with a  much smaller model because it's a  

62:18

much better dataset and you could train it on it. But probably it's not trained directly on it, it's  

62:22

probably distilled from a much better model still. But why is the distilled version still a billion? 

62:28

I just feel like distillation  works extremely well. 

62:30

So almost every small model, if you have a  small model, it's almost certainly distilled. 

62:35

Right, but why is the distillation in  10 years not getting below 1 billion? 

62:39

Oh, you think it should be smaller than a  billion? I mean, come on, right? I don't  

62:43

know. At some point it should take at least  a billion knobs to do something interesting. 

62:49

You're thinking it should be even smaller? Yeah. If you look at the trend over the last  

62:53

few years of just finding low-hanging fruit and  going from trillion plus models to models that  

62:57

are literally two orders of magnitude smaller in a  matter of two years and having better performance,  

63:03

it makes me think the sort of core of  intelligence might be even way, way smaller. 

63:09

Plenty of room at the bottom,  to paraphrase Feynman. 

63:11

I feel like I'm already contrarian  by talking about a billion parameter  

63:14

cognitive core and you're outdoing me. Maybe we could get a little bit smaller. 

63:23

I do think that practically speaking, you  want the model to have some knowledge. 

63:26

You don't want it to be looking up everything  because then you can't think in your head. 

63:30

You're looking up way too much stuff all the time. 

63:32

Some basic curriculum needs to be there for  knowledge, but it doesn't have esoteric knowledge. 

63:38

We're discussing what plausibly  could be the cognitive core. 

63:41

There's a separate question which is what  will be the size of frontier models over time? 

63:46

I'm curious if you have predictions. We had increasing scale up to maybe GPT 4.5 and  

63:51

now we're seeing decreasing or plateauing scale. There are many reasons this could be going on. 

63:56

Do you have a prediction going forward? Will the biggest models be bigger,  

64:00

will they be smaller, will they be the same? I don't have a super strong prediction. 

64:07

The labs are just being practical. They have a flops budget and a cost budget. 

64:10

It just turns out that pre-training is not where  you want to put most of your flops or your cost. 

64:14

That's why the models have gotten smaller. They are a bit smaller, the pre-training  

64:17

stage is smaller, but they make  it up in reinforcement learning,  

64:21

mid-training, and all this stuff that follows. They're just being practical in terms of all the  

64:25

stages and how you get the most bang for the buck. Forecasting that trend is quite hard. 

64:30

I do still expect that there's so much  low-hanging fruit. That's my basic expectation.  

64:38

I have a very wide distribution here. Do you expect the low-hanging fruit to be  

64:42

similar in kind to the kinds of things that have  been happening over the last two to five years? 

64:49

If I look at nanochat versus nanoGPT  and the architectural tweaks you made,  

64:54

is that the flavor of things you  expect to continue to keep happening? 

64:58

You're not expecting any giant paradigm shifts. For the most part, yeah. I expect the  

65:01

datasets to get much, much better. When you look at the average datasets,  

65:03

they're extremely terrible. They’re so bad that I  

65:05

don't even know how anything works. Look at the average example in the training set:  

65:10

factual mistakes, errors, nonsensical things. Somehow when you do it at scale,  

65:16

the noise washes away and you're left with  some of the signal. Datasets will improve  

65:21

a ton. Everything gets better. Our hardware,  all the kernels for running the hardware and  

65:29

maximizing what you get with the hardware. Nvidia is slowly tuning the hardware itself,  

65:33

Tensor Cores, all that needs to  happen and will continue to happen. 

65:36

All the kernels will get better and  utilize the chip to the max extent. 

65:39

All the algorithms will probably improve over  optimization, architecture, and all the modeling  

65:45

components of how everything is done and what  the algorithms are that we're even training with. 

65:48

I do expect that nothing dominates. Everything  plus 20%. This is roughly what I've seen. 

67:13

People have proposed different ways of charting  how much progress we've made towards full AGI. 

67:21

If you can come up with some line, then you  can see where that line intersects with AGI  

67:25

and where that would happen on the x-axis. People have proposed it's the education level. 

67:29

We had a high schooler, and then they went to  college with RL, and they're going to get a Ph.D. 

67:34

I don't like that one. Or they'll propose horizon  

67:36

length. Maybe they can do tasks that take  a minute, they can do those autonomously. 

67:41

Then they can autonomously do tasks that take  an hour, a human an hour, a human a week. 

67:46

How do you think about the relevant y-axis here? How should we think about how  

67:53

AI is making progress? I have two answers to that. 

67:55

Number one, I'm almost tempted to  reject the question entirely because  

67:59

I see this as an extension of computing. Have we talked about how to chart progress  

68:02

in computing, or how do you chart progress  in computing since the 1970s or whatever?  

68:06

What is the y-axis? The whole question is  funny from that perspective a little bit. 

68:13

When people talk about AI and the original AGI  and how we spoke about it when OpenAI started,  

68:18

AGI was a system you could go to that can do any  economically valuable task at human performance  

68:27

or better. That was the definition. I  was pretty happy with that at the time. 

68:32

I've stuck to that definition forever, and  then people have made up all kinds of other  

68:36

definitions. But I like that definition. The first  concession that people make all the time is they  

68:43

just take out all the physical stuff because  we're just talking about digital knowledge work. 

68:48

That's a pretty major concession compared to  the original definition, which was any task  

68:52

a human can do. I can lift things, etc. AI  can't do that, obviously, but we'll take it. 

68:57

What fraction of the economy are we taking away  by saying, "Oh, only knowledge work?" I don't know  

69:02

the numbers. I feel about 10% to 20%, if I had to  guess, is only knowledge work, someone could work  

69:09

from home and perform tasks, something like that. It's still a really large market. 

69:16

What is the size of the  economy, and what is 10% or 20%? 

69:19

We're still talking about a few trillion  dollars, even in the US, of market share or work. 

69:26

So it's still a very massive bucket. Going back to the definition,  

69:30

what I would be looking for is to  what extent is that definition true? 

69:35

Are there jobs or lots of tasks? If we think of tasks as not jobs but tasks. 

69:40

It's difficult because the problem is society will  refactor based on the tasks that make up jobs,  

69:47

based on what's automatable or not. Today, what jobs are replaceable by AI? 

69:52

A good example recently was Geoff Hinton's  prediction that radiologists would not be  

69:57

a job anymore, and this turned out  to be very wrong in a bunch of ways. 

70:00

Radiologists are alive and well and growing,  even though computer vision is really,  

70:04

really good at recognizing all the different  things that they have to recognize in images. 

70:07

It's just a messy, complicated job with a  lot of surfaces and dealing with patients  

70:11

and all this stuff in the context of it. I don't know that by that definition  

70:17

AI has made a huge dent yet. Some of the jobs that I would  

70:22

be looking for have some features that make it  very amenable to automation earlier than later. 

70:27

As an example, call center employees  often come up, and I think rightly so. 

70:30

Call center employees have a number of simplifying  properties with respect to what's automatable  

70:35

today. Their jobs are pretty simple. It's a  sequence of tasks, and every task looks similar. 

70:42

You take a phone call with a person, it's  10 minutes of interaction or whatever it is,  

70:45

probably a bit longer. In my experience, a lot longer. 

70:49

You complete some task in some scheme,  and you change some database entries  

70:53

around or something like that. So you keep repeating something  

70:55

over and over again, and that's your job. You do want to bring in the task horizon—how  

71:01

long it takes to perform a task—and  then you want to also remove context. 

71:05

You're not dealing with different parts of  services of companies or other customers. 

71:08

It's just the database, you,  and a person you're serving. 

71:11

It's more closed, it's more  understandable, it's purely digital. 

71:15

So I would be looking for those things. But even there, I'm not looking  

71:18

at full automation yet. I'm looking for an autonomy slider. 

71:21

I expect that we are not going  to instantly replace people. 

71:25

We're going to be swapping in  AIs that do 80% of the volume. 

71:29

They delegate 20% of the volume to humans,  and humans are supervising teams of five AIs  

71:33

doing the call center work that's more rote. I would be looking for new interfaces or new  

71:39

companies that provide some  layer that allows you to manage  

71:44

some of these AIs that are not yet perfect. Then I would expect that across the economy. 

71:48

A lot of jobs are a lot harder  than a call center employee. 

71:52

With radiologists, I'm totally  speculating and I have no idea what  

71:56

the actual workflow of a radiologist involves. But one analogy that might be applicable is when  

72:03

Waymos were first being rolled out, there'd be a  person sitting in the front seat, and you just had  

72:09

to have them there to make sure that if something  went really wrong, they're there to monitor. 

72:12

Even today, people are still watching  to make sure things are going well. 

72:15

Robotaxi, which was just deployed,  still has a person inside it. 

72:19

Now we could be in a similar situation where  if you automate 99% of a job, that last 1%  

72:25

the human has to do is incredibly valuable  because it's bottlenecking everything else. 

72:29

If it were the case with radiologists, where  the person sitting in the front of Waymo has  

72:35

to be specially trained for years in order  to provide the last 1%, their wages should  

72:39

go up tremendously because they're the  one thing bottlenecking wide deployment. 

72:43

Radiologists, I think their wages have  gone up for similar reasons, if you're  

72:46

the last bottleneck and you're not fungible. A Waymo driver might be fungible with others. 

72:53

So you might see this thing where your wages  go up until you get to 99% and then fall just  

72:57

like that when the last 1% is gone. And I wonder if we're seeing similar  

73:02

things with radiology or salaries of call  center workers or anything like that. 

73:07

That's an interesting question. I don't think  we're currently seeing that with radiology. 

73:15

I think radiology is not a good example. I don't know why Geoff Hinton picked  

73:19

on radiology because I think it's an  extremely messy, complicated profession. 

73:25

I would be a lot more interested in what's  happening with call center employees today,  

73:28

for example, because I would expect a lot  of the rote stuff to be automatable today. 

73:32

I don't have first-level access to it but  I would be looking for trends of what's  

73:36

happening with the call center employees. Some of the things I would also expect  

73:40

is that maybe they are swapping in AI, but  then I would still wait for a year or two  

73:45

because I would potentially expect them to  pull back and rehire some of the people. 

73:49

There's been evidence that that's already been  happening generally in companies that have been  

73:53

adopting AI, which I think is quite surprising. I also found what was really surprising. AGI,  

73:59

right? A thing which would do everything. We'll take out physical work,  

74:04

but it should be able to do all knowledge work. What you would have naively anticipated is that  

74:09

the way this progression would happen is  that you take a little task that a consultant  

74:14

is doing, you take that out of the bucket. You take a little task that an accountant is  

74:19

doing, you take that out of the bucket. Then you're just doing this  

74:22

across all knowledge work. But instead, if we do believe we're  

74:25

on the path of AGI with the current paradigm,  the progression is very much not like that. 

74:30

It does not seem like consultants and accountants  are getting huge productivity improvements. 

74:34

It's very much like programmers are getting  more and more chiseled away at their work. 

74:39

If you look at the revenues of these companies,  discounting normal chat revenue—which is similar  

74:46

to Google or something—just looking at  API revenues, it's dominated by coding. 

74:51

So this thing which is "general", which  should be able to do any knowledge work,  

74:56

is just overwhelmingly doing only coding. It's a surprising way that you would  

75:00

expect the AGI to be deployed. There's an interesting point  

75:04

here. I do believe coding is the perfect  first thing for these LLMs and agents. 

75:12

That’s because coding has always  fundamentally worked around text. 

75:17

It's computer terminals and text,  and everything is based around text. 

75:20

LLMs, the way they're trained  on the Internet, love text. 

75:24

They're perfect text processors, and there's  all this data out there. It's a perfect fit.  

75:29

We also have a lot of infrastructure  pre-built for handling code and text. 

75:33

For example, we have Visual Studio Code  or your favorite IDE showing you code,  

75:41

and an agent can plug into that. If an agent has a diff where it made some change,  

75:45

we suddenly have all this code already that shows  all the differences to a code base using a diff. 

75:51

It's almost like we've pre-built a  lot of the infrastructure for code. 

75:55

Contrast that with some of the  things that don't enjoy that at all. 

75:58

As an example, there are people trying to build  automation not for coding, but for slides. 

76:03

I saw a company doing slides. That's  much, much harder. The reason it's  

76:07

much harder is because slides are not text. Slides are little graphics, they're arranged  

76:11

spatially, and there's a visual component to it. Slides don't have this pre-built infrastructure. 

76:18

For example, if an agent is to make a change to  your slides, how does a thing show you the diff? 

76:24

How do you see the diff? There's nothing that shows diffs  

76:26

for slides. Someone has to build it. Some of these  things are not amenable to AIs as they are, which  

76:34

are text processors, and code surprisingly is. I’m not sure that alone explains it. 

76:42

I personally have tried to get LLMs to be useful  in domains which are just pure language-in,  

76:49

language-out, like rewriting transcripts,  coming up with clips based on transcripts. 

76:57

It's very plausible that I didn't do  every single possible thing I could do. 

77:00

I put a bunch of good examples in context, but  maybe I should have done some kind of fine-tuning. 

77:06

Our mutual friend, Andy Matuschak, told me that  he tried 50 billion things to try to get models  

77:13

to be good at writing spaced repetition prompts. Again, very much language-in, language-out tasks,  

77:19

the kind of thing that should be dead  center in the repertoire of these LLMs. 

77:22

He tried in-context learning  with a few-shot examples. 

77:25

He tried supervised fine-tuning and retrieval. He could not get them to make  

77:35

cards to his satisfaction. So I find it striking that even in language-out  

77:39

domains, it's very hard to get a lot of economic  value out of these models separate from coding. 

77:45

I don't know what explains it. That makes sense. I'm not  

77:52

saying that anything text is trivial. I do think that code is pretty structured. 

77:58

Text is maybe a lot more flowery, and there's  a lot more entropy in text, I would say. 

78:04

I don't know how else to put it. Also code is hard, and so people feel quite  

78:10

empowered by LLMs, even from simple knowledge. I don't know that I have a very good answer. 

78:19

Obviously, text makes it much, much easier,  but it doesn't mean that all text is trivial. 

78:25

How do you think about superintelligence? Do you expect it to feel qualitatively different  

78:29

from normal humans or human companies? I see it as a progression  

78:37

of automation in society. Extrapolating the trend of computing, there will  

78:42

be a gradual automation of a lot of things, and  superintelligence will an extrapolation of that. 

78:47

We expect more and more autonomous  entities over time that are doing a lot  

78:50

of the digital work and then eventually even  the physical work some amount of time later. 

78:56

Basically I see it as just  automation, roughly speaking. 

79:00

But automation includes the things humans  can already do, and superintelligence  

79:03

implies things humans can’t do. But one of the things that people  

79:05

do is invent new things, which I would just  put into the automation if that makes sense. 

79:10

But I guess, less abstractly and more  qualitatively, do you expect something  

79:18

to feel like… Because this thing can either think  so fast, or has so many copies, or the copies can  

79:26

merge back into themselves, or is much smarter,  any number of advantages an AI might have, will  

79:36

the civilization in which these AIs exist just feel qualitatively different from humans? 

79:39

I think it will. It is fundamentally automation,  but it will be extremely foreign. It will look  

79:44

really strange. Like you mentioned, we can run  all of this on a computer cluster and much faster. 

79:53

Some of the scenarios that I start to get  nervous about when the world looks like  

79:58

that is this gradual loss of control  and understanding of what's happening. 

80:01

I think that's the most likely outcome, that  there will be a gradual loss of understanding. 

80:07

We'll gradually layer all this stuff  everywhere, and there will be fewer  

80:10

and fewer people who understand it. Then there will be a gradual loss of  

80:14

control and understanding of what's happening. That to me seems the most likely outcome of how  

80:19

all this stuff will go down. Let me probe on that a bit. 

80:22

It's not clear to me that loss of control and  loss of understanding are the same things. 

80:27

A board of directors at TSMC, Intel—name a random  company—they're just prestigious 80-year-olds. 

80:37

They have very little understanding, and maybe  they don't practically actually have control. 

80:43

A better example  

80:43

is the President of the United States. The President has a lot of fucking power. 

80:48

I'm not trying to make a good statement  about the current operant, or maybe I am,  

80:53

but the actual level of understanding is  very different from the level of control. 

80:56

I think that's fair. That's a good  pushback. I think I expect loss of both. 

81:05

How come? Loss of understanding is  obvious, but why loss of control? 

81:10

We're really far into a territory where I  don't know what this looks like, but if I  

81:14

were to write sci-fi novels, they would look along  the lines of not even a single entity that takes  

81:22

over everything, but multiple competing entities  that gradually become more and more autonomous. 

81:27

Some of them go rogue and  the others fight them off. 

81:31

It's this hot pot of completely autonomous  activity that we've delegated to. 

81:37

I feel it would have that flavor. It is not the fact that they are smarter  

81:43

than us that is resulting in the loss of control. It's the fact that they are competing with each  

81:47

other, and whatever arises out of that  competition leads to the loss of control. 

81:58

A lot of these things, they will be  tools to people, they're acting on  

82:04

behalf of people or something like that. So maybe those people are in control,  

82:07

but maybe it's a loss of control overall for  society in the sense of outcomes we want. 

82:13

You have entities acting on behalf of individuals  that are still roughly seen as out of control. 

82:20

This is a question I should have asked earlier. We were talking about how currently it feels like  

82:24

when you're doing AI engineering or AI research,  these models are more in the category of compiler  

82:29

rather than in the category of a replacement. At some point, if you have AGI,  

82:34

it should be able to do what you do. Do you feel like having a million  

82:38

copies of you in parallel results in  some huge speed-up of AI progress? 

82:43

If that does happen, do you expect to see an  intelligence explosion once we have a true AGI? 

82:49

I'm not talking about LLMs today. I do, but it's business as usual because  

82:56

we're in an intelligence explosion  already and have been for decades. 

83:00

It's basically the GDP curve that is  an exponential weighted sum over so  

83:03

many aspects of the industry. Everything is gradually being  

83:06

automated and has been for hundreds of years. The Industrial Revolution is automation and  

83:10

some of the physical components and  tool building and all this stuff. 

83:13

Compilers are early software  automation, et cetera. 

83:16

We've been recursively self-improving  and exploding for a long time. 

83:21

Another way to see it is that Earth was a pretty  boring place if you don't look at the biomechanics  

83:27

and so on, and looked very similar. If you look from space, we're in the  

83:33

middle of this firecracker event,  but we're seeing it in slow motion. 

83:38

I definitely feel like this has  already happened for a very long time. 

83:42

Again, I don't see AI as a distinct  technology with respect to what has  

83:47

already been happening for a long time. You think it's continuous with this  

83:50

hyper-exponential trend? Yes. That's why this was  

83:53

very interesting to me, because I was  trying to find AI in the GDP for a while. 

83:57

I thought that GDP should go up. But then I looked at some of the  

84:01

other technologies that I thought  were very transformative, like  

84:04

computers or mobile phones or et cetera. You can't find them in GDP. GDP is the same  

84:08

exponential. Even the early iPhone didn't have the  App Store, and it didn't have a lot of the bells  

84:13

and whistles that the modern iPhone has. So even though we think of 2008,  

84:18

when the iPhone came out, as this major  seismic change, it's actually not. 

84:21

Everything is so spread out and it so  slowly diffuses that everything ends up  

84:25

being averaged up into the same exponential. It's the exact same thing with computers. 

84:28

You can't find them in the GDP  like, "Oh, we have computers now." 

84:31

That's not what happened, because  it's such slow progression. 

84:33

With AI we're going to see the exact same thing.  It's just more automation. It allows us to write  

84:37

different kinds of programs that we couldn't write  before, but AI is still fundamentally a program. 

84:42

It's a new kind of computer and  a new kind of computing system. 

84:46

But it has all these problems,  it's going to diffuse over time,  

84:49

and it's still going to add  up to the same exponential. 

84:52

We're still going to have an exponential  that's going to get extremely vertical. 

84:56

It's going to be very foreign to  live in that kind of an environment. 

84:59

Are you saying that, if you look at the trend  before the Industrial Revolution to now,  

85:05

you have a hyper-exponential where you go  from 0% growth to then 10,000 years ago,  

85:11

0.02% growth, and to now when we're at 2%  growth. That's a hyper-exponential. Are you  

85:15

saying if you're charting AI on there, then  AI takes you to 20% growth or 200% growth? 

85:20

Or are you saying that if you look at  the last 300 years, what you've been  

85:23

seeing is that you have technology after  technology—computers, electrification,  

85:27

steam engines, railways, et cetera—but the  rate of growth is the exact same, it's 2%. 

85:33

Are you saying the rate of growth will go up? The rate of growth has also stayed  

85:38

roughly constant, right? Only over the last 200, 300 years. 

85:41

But over the course of  human history it's exploded. 

85:44

It's gone from 0% to faster, faster,  faster. Industrial explosion, 2%. 

85:51

For a while I tried to find AI  or look for AI in the GDP curve,  

85:54

and I've convinced myself that this is false. Even when people talk about recursive  

85:58

self-improvement and labs and stuff  like that, this is business as usual. 

86:01

Of course it's going to recursively self-improve,  and it's been recursively self-improving. 

86:05

LLMs allow the engineers to work much more  efficiently to build the next round of LLM,  

86:11

and a lot more of the components are  being automated and tuned and et cetera. 

86:14

All the engineers having access  to Google Search is part of it. 

86:19

All the engineers having an IDE, all of them  having autocomplete or having Claude code,  

86:23

et cetera, it's all just part of the same  speed-up of the whole thing. It's just so smooth. 

86:30

Just to clarify, you're saying that  the rate of growth will not change. 

86:35

The intelligence explosion will show up as  it just enabled us to continue staying on the  

86:39

2% growth trajectory, just as the Internet  helped us stay on the 2% growth trajectory. 

86:42

Yes, my expectation is that  it stays in the same pattern. 

86:47

Just to throw the opposite argument against you,  my expectation is that it blows up because I think  

86:55

true AGI—and I'm not talking about LLM coding  bots, I'm talking about actual replacement of a  

87:00

human in a server—is qualitatively different  from these other productivity-improving  

87:07

technologies because it's labor itself. I think we live in a very labor-constrained world. 

87:13

If you talk to any startup founder or any person,  you can be like, what do you need more of? You  

87:17

need really talented people. And if you have  billions of extra people who are inventing stuff,  

87:22

integrating themselves, making companies bottom  start to finish, that feels qualitatively  

87:28

different from a single technology. It's as if you get 10 billion  

87:32

extra people on the planet. Maybe a counterpoint. I'm pretty willing  

87:37

to be convinced one way or another on this point. But I will say, for example, computing is labor.  

87:42

Computing was labor. Computers, a lot  of jobs disappeared because computers  

87:45

are automating a bunch of digital information  processing that you now don't need a human for. 

87:50

So computers are labor, and that has played out. Self-driving as an example is also computers doing  

87:57

labor. That's already been playing  out. It's still business as usual. 

88:02

You have a machine which is spitting out more  things like that at potentially faster pace. 

88:08

Historically, we have examples  of the growth regime changing  

88:11

where you went from 0.2% growth to 2% growth. It seems very plausible to me that a machine which  

88:18

is then spitting out the next self-driving  car and the next Internet and whatever… 

88:23

I see where it's coming from. At the same time, I do feel like  

88:27

people make this assumption of, "We  have God in a box, and now it can do  

88:31

everything," and it just won't look like that. It's going to be able to do some of the things. 

88:36

It's going to fail at some other things. It's going to be gradually put into society,  

88:39

and we'll end up with the same pattern. That  is my prediction. This assumption of suddenly  

88:43

having a completely intelligent, fully flexible,  fully general human in a box, and we can dispense  

88:49

it at arbitrary problems in society, I don't  think that we will have this discrete change. 

88:57

I think we'll arrive at the same kind of  gradual diffusion of this across the industry. 

89:03

It often ends up being misleading  in these conversations. 

89:09

I don't like to use the word intelligence in  this context because intelligence implies you  

89:12

think there'll be a single superintelligence  sitting in a server and it'll divine how  

89:18

to come up with new technologies and  inventions that cause this explosion. 

89:22

That's not what I'm imagining  when I'm imagining 20% growth. 

89:25

I'm imagining that there are billions of  very smart human-like minds, potentially,  

89:33

or that's all that's required. But the fact that there's hundreds  

89:36

of millions of them, billions of them, each  individually making new products, figuring  

89:41

out how to integrate themselves into the economy. If a highly experienced smart immigrant came to  

89:46

the country, you wouldn't need to figure out how  we integrate them in the economy. They figure it  

89:49

out. They could start a company, they could make  inventions, or increase productivity in the world. 

89:55

We have examples, even in the current regime,  of places that have had 10-20% economic growth. 

90:01

If you just have a lot of people and  less capital in comparison to the people,  

90:05

you can have Hong Kong or Shenzhen or  whatever with decades of 10% plus growth. 

90:13

There's a lot of really smart people who are  ready to make use of the resources and do  

90:17

this period of catch-up because we've had this  discontinuity, and I think AI might be similar. 

90:24

I understand, but I still think that  you're presupposing some discrete jump. 

90:28

There's some unlock that we're waiting to claim. And suddenly we're going to have  

90:31

geniuses in data centers. I still think you're presupposing  

90:34

some discrete jump that has no historical  precedent that I can't find in any of the  

90:39

statistics and that I think probably won't happen. I mean, the Industrial Revolution is such a jump. 

90:43

You went from 0.2% growth to 2% growth. I'm just saying you'll see another jump like that. 

90:49

I'm a little bit suspicious,  I would have to take a look. 

90:53

For example, some of the logs are not very  good from before the Industrial Revolution. 

90:59

I'm a bit suspicious of it but  I don't have strong opinions. 

91:04

You're saying that this was a singular  event that was extremely magical. 

91:07

You're saying that maybe there's going  to be another event that's going to  

91:09

be just like that, extremely magical. It will break the paradigm, and so on. 

91:12

I actually don't think… The crucial thing with the  Industrial Revolution was that it was not magical. 

91:18

If you just zoomed in, what you would see in 1770  or 1870 is not that there was some key invention. 

91:28

But at the same time, you did move the  economy to a regime where the progress  

91:32

was much faster and the exponential 10x'd. I expect a similar thing from AI where it's  

91:37

not like there's going to be a single moment  where we've made the crucial invention. 

91:42

It’s an overhang that's being unlocked. Like maybe there's a new energy source. 

91:45

There's some unlock—in this case, some kind of  a cognitive capacity—and there's an overhang of  

91:49

cognitive work to do. That's right. 

91:52

You're expecting that overhang to be filled by  this new technology when it crosses the threshold. 

91:56

Maybe one way to think about it is  throughout history, a lot of growth  

92:01

comes because people come up with ideas,  and then people are out there doing stuff to  

92:06

execute those ideas and make valuable output. Through most of this time, the population has  

92:11

been exploding. That has been driving  growth. For the last 50 years, people  

92:14

have argued that growth has stagnated. The population in frontier countries  

92:17

has also stagnated. I think we go back to  

92:19

the exponential growth in population that  causes hyper-exponential growth in output. 

92:28

It's really hard to tell. I  understand that viewpoint. I  

92:32

don't intuitively feel that viewpoint. You recommended Nick Lane's book to me. 

93:40

On that basis, I also found it super  interesting and I interviewed him. 

93:45

I have some questions about thinking about  intelligence and evolutionary history. 

93:49

Now that you, over the last 20 years of doing AI  research, you maybe have a more tangible sense of  

93:54

what intelligence is, what it takes to develop it. Are you more or less surprised as a result that  

94:01

evolution just spontaneously stumbled upon it? I love Nick Lane's books. I was just listening  

94:12

to his podcast on the way up here. With respect to intelligence and its  

94:15

evolution, it's very, very recent. I am surprised that it evolved. 

94:23

I find it fascinating to think  about all the worlds out there. 

94:25

Say there's a thousand planets  like Earth and what they look like. 

94:27

I think Nick Lane was here talking  about some of the earliest parts. 

94:30

He expects very similar life  forms, roughly speaking,  

94:34

and bacteria-like things in most of them. There are a few breaks in there. 

94:39

The evolution of intelligence intuitively feels  to me like it should be a fairly rare event. 

94:45

Maybe you should base it on  how long something has existed. 

94:49

If bacteria were around for 2 billion years  and nothing happened, then going to eukaryote  

94:52

is probably pretty hard because bacteria came  up quite early in Earth's evolution or history. 

95:02

How long have we had animals? Maybe a couple hundred million years,  

95:04

multicellular animals that  run around, crawl, et cetera. 

95:08

That’s maybe 10% of Earth's lifespan. Maybe on that timescale it's not too tricky. 

95:18

It's still surprising to me,  intuitively, that it developed. 

95:20

I would maybe expect just a lot of animal-like  life forms doing animal-like things. 

95:24

The fact that you can get something  that creates culture and knowledge  

95:28

and accumulates it is surprising to me. There's a couple of interesting follow-ups. 

95:35

If you buy the Sutton perspective that the  crux of intelligence is animal intelligence…  

95:41

The quote he said is "If you got to the  squirrel, you'd be most of the way to AGI." 

95:46

We got to squirrel intelligence right after  the Cambrian explosion 600 million years ago. 

95:51

It seems like what instigated that was the  oxygenation event 600 million years ago. 

95:56

But immediately the intelligence algorithm  was there to make the squirrel intelligence. 

96:02

It's suggestive that animal  intelligence was like that. 

96:06

As soon as you had the oxygen in the  environment, you had the eukaryote,  

96:09

you could just get the algorithm. Maybe it was an accident that  

96:14

evolution stumbled upon it so fast,  but I don't know if that suggests that  

96:18

at the end it's going to be quite simple. It's so hard to tell with any of this stuff. 

96:23

You can base it a bit on how long  something has existed or how long  

96:26

it feels like something has been bottlenecked. Nick Lane is very good about describing this very  

96:30

apparent bottleneck in bacteria and archaea. For two billion years, nothing happened. 

96:34

There’s extreme diversity of biochemistry,  and yet nothing grows to become animals.  

96:41

Two billion years. I don't know that we've  seen exactly that kind of an equivalent with  

96:46

animals and intelligence, to your point. We could also look at it with respect  

96:51

to how many times we think certain  intelligence has individually sprung up. 

96:55

That's a really good thing to investigate. One thought on that. There's hominid intelligence,  

97:03

and then there's bird intelligence. Ravens, etc., are extremely clever,  

97:07

but their brain parts are quite distinct,  and we don't have that much in common. 

97:13

That's a slight indication of maybe  intelligence springing up a few times. 

97:18

In that case, you'd expect it more frequently. A former guest, Gwern, and Carl Shulman, they’ve  

97:26

made a really interesting point about that. Their perspective is that the scalable algorithm  

97:32

which humans have and primates have, arose in  birds as well, and maybe other times as well. 

97:39

But humans found an evolutionary niche which  rewarded marginal increases in intelligence  

97:47

and also had a scalable brain algorithm that  could achieve those increases in intelligence. 

97:53

For example, if a bird had a bigger brain,  it would just collapse out of the air. 

97:57

It's very smart for the size of  its brain, but it's not in a niche  

98:00

which rewards the brain getting bigger. It’s maybe similar to some really smart… 

98:08

Like dolphins? Exaclty, humans, we have hands that  

98:10

reward being able to learn how to do tool use. We can externalize digestion, more energy to  

98:14

the brain, and that kicks off the flywheel. Also stuff to work with. I'm guessing it would  

98:19

be harder if I were a dolphin. How do you have  fire? The universe of things you can do in water,  

98:28

inside water, is probably lower than  what you can do on land, just chemically. 

98:33

I do agree with this viewpoint of these niches  and what's being incentivized. I still find it  

98:38

miraculous. I would have expected things to  get stuck on animals with bigger muscles. 

98:47

Going through intelligence is a  really fascinating breaking point. 

98:51

The way Gwern put it is the reason it was so hard  is that it's a very tight line between being in  

98:56

a situation where something is so important  to learn that it's not worth distilling the  

99:03

exact right circuits directly back into your DNA,  versus it's not important enough to learn at all. 

99:10

It has to be something that incentivizes  building the algorithm to learn in a lifetime. 

99:17

You have to incentivize some kind of adaptability. You want environments that are unpredictable  

99:21

so evolution can't bake your  algorithms into your weights. 

99:24

A lot of animals are pre-baked in this sense. Humans have to figure it out at test  

99:30

time when they get born. You want these environments  

99:35

that change really rapidly, where you  can't foresee what will work well. 

99:42

You create intelligence to  figure it out at test time. 

99:45

Quintin Pope had this interesting blog post  where he's saying the reason he doesn't  

99:48

expect a sharp takeoff is that humans had the  sharp takeoff where 60,000 years ago we seem  

99:55

to have had the cognitive architectures  that we have today. 10,000 years ago,  

99:59

agricultural revolution, modernity. What was happening in that 50,000 years? 

100:04

You had to build this cultural scaffold where  you can accumulate knowledge over generations. 

100:11

This is an ability that exists for  free in the way we do AI training. 

100:16

In many cases they are literally distilled. If you retrain a model, they can be trained  

100:21

on each other, they can be trained  on the same pre-training corpus,  

100:25

they don't literally have to start from scratch. There's a sense in which it took humans a long  

100:31

time to get this cultural loop going, but it just  comes for free with the way we do LLM training. 

100:36

Yes and no. Because LLMs don't really  have the equivalent of culture. 

100:39

Maybe we're giving them way too  much and incentivizing not to  

100:42

create it or something like that. But the invention of culture and of  

100:45

written record and of passing down notes  between each other, I don't think there's  

100:48

an equivalent of that with LLMs right now. LLMs don't really have culture right now and  

100:53

it's one of the impediments I would say. Can you give me some sense of what  

100:58

LLM culture might look like? In the simplest case it would be a  

101:01

giant scratchpad that the LLM can edit and as it's  reading stuff or as it's helping out with work,  

101:06

it's editing the scratchpad for itself. Why can't an LLM write a book for the other  

101:10

LLMs? That would be cool. Why can't other  LLMs read this LLM's book and be inspired  

101:16

by it or shocked by it or something like that? There's no equivalence for any of this stuff. 

101:20

Interesting. When would you expect  that kind of thing to start happening? 

101:24

Also, multi-agent systems and a sort of  independent AI civilization and culture? 

101:31

There are two powerful ideas in the  realm of multi-agent that have both  

101:34

not been really claimed or so on. The first one I would say is culture  

101:38

and LLMs having a growing repertoire  of knowledge for their own purposes. 

101:44

The second one looks a lot more  like the powerful idea of self-play. 

101:47

In my mind it’s extremely powerful. Evolution has a lot of competition  

101:53

driving intelligence and evolution. In AlphaGo more algorithmically,  

101:59

AlphaGo is playing against itself and that's  how it learns to get really good at Go. 

102:03

There's no equivalent of self-playing LLMs,  but I would expect that to also exist. 

102:07

No one has done it yet. Why can't an LLM for example, create a bunch  

102:10

of problems that another LLM is learning to solve? Then the LLM is always trying to serve more and  

102:16

more difficult problems, stuff like that. There's a bunch of ways to organize it. 

102:22

It's a realm of research, but I haven't  seen anything that convincingly claims  

102:26

both of those multi-agent improvements. We're mostly in the realm of a single  

102:31

individual agent, but that will change. In the realm of culture also,  

102:37

I would also bucket organizations. We haven't seen anything like that convincingly  

102:41

either. That's why we're still early. Can you identify the key bottleneck  

102:45

that's preventing this kind  of collaboration between LLMs? 

102:50

Maybe the way I would put it is,  some of these analogies work and  

102:56

they shouldn't, but somehow, remarkably, they do. A lot of the smaller models, or the dumber models,  

103:01

remarkably resemble a kindergarten student, or an  elementary school student or high school student. 

103:07

Somehow, we still haven't graduated  enough where this stuff can take over. 

103:12

My Claude Code or Codex, they still  feel like this elementary-grade student. 

103:17

I know that they can take PhD quizzes,  but they still cognitively feel like a  

103:21

kindergarten or an elementary school student. I don't think they can create culture because  

103:24

they're still kids. They're savant kids.  They have perfect memory of all this stuff. 

103:33

They can convincingly create all  kinds of slop that looks really good. 

103:36

But I still think they don't really know  what they're doing and they don't really  

103:38

have the cognition across all these little  checkboxes that we still have to collect. 

103:43

You've talked about how you were at Tesla  leading self-driving from 2017 to 2022. 

103:50

And you firsthand saw this progress from cool  demos to now thousands of cars out there actually  

103:58

autonomously doing drives. Why did that take a decade? 

104:01

What was happening through that time? One thing I will almost instantly push  

104:06

back on is that this is not even near done,  in a bunch of ways that I'm going to get to. 

104:13

Self-driving is very interesting because  it's definitely where I get a lot of my  

104:16

intuitions because I spent five years on it. It has this entire history where the first demos  

104:22

of self-driving go all the way to the 1980s. You can see a demo from CMU in 1986. 

104:28

There's a truck that's driving itself on  roads. Fast forward. When I was joining Tesla,  

104:34

I had a very early demo of Waymo. It basically gave me a perfect drive  

104:40

in 2014 or something like that, so  a perfect Waymo drive a decade ago. 

104:46

It took us around Palo Alto and so on  because I had a friend who worked there. 

104:50

I thought it was very close and  then it still took a long time. 

104:54

For some kinds of tasks and jobs and so on,  there's a very large demo-to-product gap where the  

105:02

demo is very easy, but the product is very hard. It's especially the case in cases like  

105:07

self-driving where the cost  of failure is too high. 

105:11

Many industries, tasks, and jobs maybe don't have  that property, but when you do have that property,  

105:15

that definitely increases the timelines. For example, in software engineering,  

105:19

I do think that property does exist. For a lot of vibe coding, it doesn't. 

105:24

But if you're writing actual production-grade  code, that property should exist, because any  

105:28

kind of mistake leads to a security  vulnerability or something like that. 

105:32

Millions and hundreds of millions of  people's personal Social Security numbers  

105:36

get leaked or something like that. So in software, people should be careful,  

105:42

kind of like in self-driving. In self-driving, if things go wrong,  

105:46

you might get injured. There are worse  outcomes. But in software, it's almost  

105:52

unbounded how terrible something could be. I do think that they share that property. 

105:59

What takes the long amount of time and the way  to think about it is that it's a march of nines. 

106:04

Every single nine is a constant amount of work. Every single nine is the same amount of work. 

106:10

When you get a demo and something works 90%  of the time, that's just the first nine. 

106:16

Then you need the second nine, a third  nine, a fourth nine, a fifth nine. 

106:18

While I was at Tesla for five years or so, we  went through maybe three nines or two nines. 

106:23

I don't know what it is, but  multiple nines of iteration. 

106:25

There are still more nines to go. That's why these things take so long. 

106:31

It's definitely formative for me, seeing  something that was a demo. I'm very  

106:35

unimpressed by demos. Whenever I see demos of  anything, I'm extremely unimpressed by that. 

106:43

If it's a demo that someone cooked  up as a showing, it's worse. 

106:45

If you can interact with it, it's a bit better. 

106:47

But even then, you're not done. You need the  actual product. It's going to face all these  

106:50

challenges when it comes in contact  with reality and all these different  

106:53

pockets of behavior that need patching. We're going to see all this stuff play  

106:57

out. It's a march of nines. Each nine is  constant. Demos are encouraging. It’s still  

107:01

a huge amount of work to do. It is a critical safety domain,  

107:07

unless you're doing vibe coding,  which is all nice and fun and so on. 

107:11

That's why this also enforced my  timelines from that perspective. 

107:16

It's very interesting to hear you say that, that  the safety guarantees you need from software  

107:20

are not dissimilar to self-driving. What people will often say is that  

107:24

self-driving took so long because  the cost of failure is so high. 

107:30

A human makes a mistake on average every  400,000 miles or every seven years. 

107:34

If you had to release a coding agent that  couldn't make a mistake for at least seven years,  

107:39

it would be much harder to deploy. But your point is that if you made a  

107:43

catastrophic coding mistake, like breaking  some important system every seven years... 

107:47

Very easy to do. In fact, in terms of wall clock time,  

107:51

it would be much less than seven years because  you're constantly outputting code like that. 

107:57

In terms of tokens, it would be seven years. But in terms of wall clock time... 

108:00

In some ways, it's a much harder problem. Self-driving is just one of  

108:02

thousands of things that people do. It's almost like a single vertical, I suppose. 

108:07

Whereas when we're talking about  general software engineering,  

108:08

it's even more... There's more surface area. There's another objection people make to that  

108:14

analogy, which is that with self-driving, what  took a big fraction of that time was solving  

108:21

the problem of having basic perception  that's robust, building representations,  

108:27

and having a model that has some common  sense so it can generalize to when it sees  

108:32

something that's slightly out of distribution. If somebody's waving down the road this way,  

108:37

you don't need to train for it. The thing will have some understanding  

108:40

of how to respond to something like that. These are things we're getting for free  

108:44

with LLMs or VLMs today, so we don't have to  solve these very basic representation problems. 

108:49

So now deploying AIs across different domains  will sort of be like deploying a self-driving  

108:54

car with current models to a different city,  which is hard but not like a 10-year-long task. 

108:59

I'm not 100% sure if I fully agree with that. I don't know how much we're getting for free. 

109:03

There's still a lot of gaps in  understanding what we are getting. 

109:07

We're definitely getting more  generalizable intelligence in a  

109:10

single entity, whereas self-driving is a  very special-purpose task that requires. 

109:14

In some sense building a special-purpose task  is maybe even harder in a certain sense because  

109:18

it doesn't fall out from a more general thing  that you're doing at scale, if that makes sense. 

109:24

But the analogy still doesn't fully  resonate because the LLMs are still  

109:30

pretty fallible and they have a lot of  gaps that still need to be filled in. 

109:33

I don't think that we're  getting magical generalization  

109:35

completely out of the box, in a certain sense. The other aspect that I wanted to return to is  

109:42

that self-driving cars are nowhere near done  still. The deployments are pretty minimal.  

109:51

Even Waymo and so on has very few cars. They're doing that roughly speaking  

109:54

because they're not economical. They've built something that lives in the future. 

110:00

They've had to pull back the future,  but they had to make it uneconomical. 

110:05

There are all these costs, not just  marginal costs for those cars and  

110:09

their operation and maintenance, but  also the capex of the entire thing. 

110:13

Making it economical is still  going to be a slog for them. 

110:17

Also, when you look at these cars and  there's no one driving, I actually think  

110:21

it's a little bit deceiving because there  are very elaborate teleoperation centers  

110:26

of people kind of in a loop with these cars. I don't have the full extent of it, but there's  

110:32

more human-in-the-loop than you might expect. There are people somewhere out there  

110:36

beaming in from the sky. I don't know if they're  

110:39

fully in the loop with the driving. Some of the time they are, but they're  

110:42

certainly involved and there are people. In some sense, we haven't actually removed  

110:45

the person, we've moved them to  somewhere where you can't see them. 

110:48

I still think there will be some work, as you  mentioned, going from environment to environment. 

110:52

There are still challenges  to make self-driving real. 

110:55

But I do agree that it's definitely crossed  a threshold where it kind of feels real,  

110:59

unless it's really teleoperated. For example, Waymo can't go to  

111:03

all the different parts of the city. My suspicion is that it's parts of the city  

111:07

where you don't get good signal. Anyway, I don't know anything  

111:11

about the stack. I'm just making stuff up. You led self-driving for five years at Tesla. 

111:17

Sorry, I don't know anything  about the specifics of Waymo. 

111:21

By the way, I love Waymo  and I take it all the time. 

111:24

I just think that people are sometimes a  little bit too naive about some of the progress  

111:29

and there's still a huge amount of work. Tesla took in my mind a much more scalable  

111:33

approach and the team is doing extremely well. I'm kind of on the record for predicting  

111:39

how this thing will go. Waymo had an early start  

111:42

because you can package up so many sensors. But I do think Tesla is taking the more  

111:45

scalable strategy and it's going  to look a lot more like that. 

111:48

So this will still have to play out and hasn't. But I don't want to talk about self-driving as  

111:54

something that took a decade because it  didn't take it yet, if that makes sense. 

111:59

Because one, the start is at 1980 and not 10  years ago, and then two, the end is not here yet. 

112:05

The end is not near yet because when  we're talking about self-driving,  

112:08

usually in my mind it's self-driving at scale. People don't have to get a driver's license, etc. 

112:13

I'm curious to bounce two other ways in  which the analogy might be different. 

112:19

The reason I'm especially curious about this is  because the question of how fast AI is deployed,  

112:24

how valuable it is when it's early  on is potentially the most important  

112:28

question in the world right now. If you're trying to model what the  

112:31

year 2030 looks like, this is the question  you ought to have some understanding of. 

112:36

Another thing you might think is one, you have  this latency requirement with self-driving. 

112:42

I have no idea what the actual models are, but I  assume it’s like tens of millions of parameters  

112:45

or something, which is not the necessary  constraint for knowledge work with LLMs. 

112:51

Maybe it might be with computer use and stuff. But the other big one is, maybe more  

112:56

importantly, on this capex question. Yes, there is additional cost to serving  

113:02

up an additional copy of a model, but the opex  of a session is quite low and you can amortize  

113:12

the cost of AI into the training run itself,  depending on how inference scaling goes and stuff. 

113:17

But it's certainly not as much as building a whole  new car to serve another instance of a model. 

113:23

So the economics of deploying more  widely are much more favorable. 

113:28

I think that's right. If you're  sticking to the realm of bits,  

113:31

bits are a million times easier than anything  that touches the physical world. I definitely  

113:36

grant that. Bits are completely changeable,  arbitrarily reshuffleable at a very rapid speed. 

113:42

You would expect a much faster adaptation also in  the industry and so on. What was the first one? 

113:50

The latency requirements and  its implications for model size? 

113:53

I think that's roughly right. I also  think that if we are talking about  

113:56

knowledge work at scale, there will be some  latency requirements, practically speaking,  

114:00

because we're going to have to create a  huge amount of compute and serve that. 

114:06

The last aspect that I very briefly want  to also talk about is all the rest of it. 

114:13

What does society think about it? What are  the legal ramifications? How is it working  

114:17

legally? How is it working insurance-wise?  What are those layers of it and aspects of it? 

114:25

What is the equivalent of people  putting a cone on a Waymo? 

114:28

There are going to be equivalents of all that. So I feel like self-driving is a very nice  

114:34

analogy that you can borrow things from. What is the equivalent of a cone in the car? 

114:38

What is the equivalent of a teleoperating worker  who's hidden away and all the aspects of it. 

114:45

Do you have any opinions on what this  implies about the current AI buildout,  

114:49

which would 10x the amount of available compute  in the world in a year or two and maybe more  

114:56

than 100x it by the end of the decade. If the use of AI will be lower than  

115:00

some people naively predict, does  that mean that we're overbuilding  

115:04

compute or is that a separate question? Kind of like what happened with railroads. 

115:08

With what, sorry? Was it railroads or? 

115:10

Yeah, it was. Yeah. There's historical precedent.  

115:14

Or was it with the telecommunication industry? Pre-paving the internet that only came a decade  

115:18

later and creating a whole bubble in the  telecommunications industry in the late '90s. 

115:28

I understand I'm sounding very pessimistic  here. I'm actually optimistic. I think this  

115:33

will work. I think it's tractable. I'm  only sounding pessimistic because when  

115:36

I go on my Twitter timeline, I see all  this stuff that makes no sense to me. 

115:42

There's a lot of reasons for why that exists. A lot of it is honestly just fundraising.  

115:47

It's just incentive structures.  A lot of it may be fundraising. 

115:50

A lot of it is just attention, converting  attention to money on the internet,  

115:55

stuff like that. There's a lot of  

116:00

that going on, and I'm only reacting to that. But I'm still overall very bullish on technology. 

116:05

We're going to work through all this stuff. There's been a rapid amount of progress. 

116:09

I don't know that there's overbuilding. I think we're going to be able to gobble up what,  

116:15

in my understanding, is being built. For example, Claude Code or OpenAI Codex  

116:20

and stuff like that didn't even  exist a year ago. Is that right?  

116:24

This is a miraculous technology that didn't exist. There's going to be a huge amount of demand,  

116:29

as we see the demand in ChatGPT already and so on. So I don't know that there's overbuilding. 

116:37

I'm just reacting to some of the very fast  timelines that people continue to say incorrectly. 

116:42

I've heard many, many times over the course  of my 15 years in AI where very reputable  

116:46

people keep getting this wrong all the time. I want this to be properly calibrated, and some  

116:53

of this also has geopolitical ramifications and  things like that with some of these questions. 

116:59

I don't want people to make  mistakes in that sphere of things. 

117:04

I do want us to be grounded in the  reality of what technology is and isn't. 

117:08

Let's talk about education and Eureka. One thing you could do is start another AI  

117:15

lab and then try to solve those problems. I’m curious what you're up to now,  

117:21

and why not AI research itself? I guess the way I would put it  

117:26

is I feel some amount of determinism  around the things that AI labs are doing. 

117:33

I feel like I could help out there, but I  don't know that I would uniquely improve it. 

117:42

My personal big fear is that a lot of this  stuff happens on the side of humanity,  

117:46

and that humanity gets disempowered by it. I care not just about all the Dyson spheres  

117:52

that we're going to build and that AI is  going to build in a fully autonomous way,  

117:55

I care about what happens to humans. I want humans to be well off in the future. 

118:00

I feel like that's where I can a  lot more uniquely add value than  

118:04

an incremental improvement in the frontier lab. I'm most afraid of something depicted in movies  

118:11

like WALL-E or Idiocracy or something like that,  where humanity is on the side of this stuff. 

118:16

I want humans to be much,  much better in this future. 

118:21

To me, this is through education  that you can achieve this. 

118:26

So what are you working on there? The easiest way I can describe it is  

118:30

we're trying to build the Starfleet Academy. I don’t know if you’ve watched Star Trek. 

118:34

I haven’t. Starfleet Academy is  

118:37

this elite institution for frontier technology,  building spaceships, and graduating cadets to be  

118:43

the pilots of these spaceships and whatnot. So I just imagine an elite institution for  

118:47

technical knowledge and a kind of school that's  very up-to-date and a premier institution. 

118:56

A category of questions I have for you is  explaining how one teaches technical or  

119:03

scientific content well, because you  are one of the world masters at it. 

119:08

I'm curious both about how you think about  it for content you've already put out there  

119:11

on YouTube, but also, to the extent it's any  different, how you think about it for Eureka. 

119:16

With respect to Eureka, one thing that  is very fascinating to me about education  

119:20

is that I do think education will pretty  fundamentally change with AIs on the side. 

119:24

It has to be rewired and changed to some extent. I still think that we're pretty early. 

119:30

There's going to be a lot of people who  are going to try to do the obvious things. 

119:33

Have an LLM and ask it questions. Do all the basic things that you would  

119:38

do via prompting right now. It's helpful,  

119:40

but it still feels to me a bit like slop. I'd like to do it properly, and I think the  

119:44

capability is not there for what I would want. What I'd want is an actual tutor experience. 

119:51

A prominent example in my mind is I was  recently learning Korean, so language learning. 

119:57

I went through a phase where I was  learning Korean by myself on the internet. 

120:00

I went through a phase where I was part of a small  class in Korea taking Korean with a bunch of other  

120:06

people, which was really funny. We had a teacher and 10  

120:08

people or so taking Korean. Then I switched to a one-on-one tutor. 

120:13

I guess what was fascinating to me was, I think  I had a really good tutor, but just thinking  

120:19

through what this tutor was doing for me and how  incredible that experience was and how high the  

120:25

bar is for what I want to build eventually. Instantly from a very short  

120:31

conversation, she understood where I am  as a student, what I know and don't know. 

120:35

She was able to probe exactly the kinds of  questions or things to understand my world model. 

120:41

No LLM will do that for you  100% right now, not even close. 

120:44

But a tutor will do that if they're good. Once she understands, she really served  

120:49

me all the things that I needed at  my current sliver of capability. 

120:52

I need to be always appropriately challenged. I can't be faced with something too hard or  

120:56

too trivial, and a tutor is really good  at serving you just the right stuff. 

121:01

I felt like I was the only constraint to learning. I was always given the perfect information. I'm  

121:07

the only constraint. I felt good because  I'm the only impediment that exists. 

121:11

It's not that I can't find knowledge or  that it's not properly explained or etc. 

121:14

It's just my ability to memorize and so on. This is what I want for people. 

121:18

How do you automate that? Very good question. At  

121:21

the current capability, you don't. That's why I think it's not actually the  

121:26

right time to build this kind of an AI tutor. I still think it's a useful product,  

121:31

and lots of people will build it, but the bar  is so high and the capability is not there. 

121:40

Even today, I would say ChatGPT is an  extremely valuable educational product. 

121:45

But for me, it was so fascinating  to see how high the bar is. 

121:48

When I was with her, I almost felt  like there's no way I can build this. 

121:53

But you are building it, right? Anyone who's had a really good  

121:55

tutor is like, "How are you going to build  this?" I'm waiting for that capability. I  

122:04

did some AI consulting for computer vision. A lot of times, the value that I brought to  

122:09

the company was telling them not to use AI. I was the AI expert, and they described the  

122:13

problem, and I said, "Don't use AI."  This is my value add. I feel like it's  

122:17

the same in education right now, where  I feel like for what I have in mind,  

122:21

it's not yet the time, but the time will come. For now, I'm building something that looks  

122:26

maybe a bit more conventional that has a  physical and digital component and so on. 

122:30

But it's obvious how this  should look in the future. 

122:35

To the extent you're willing to  say, what is the thing you hope  

122:37

will be released this year or next year? I'm building the first course. I want to  

122:43

have a really, really good course, the  obvious state-of-the-art destination  

122:48

you go to to learn, AI in this case. That's just what I'm familiar with, so it's  

122:51

a really good first product to get to be really  good at it. So that's what I'm building. Nanochat,  

122:56

which you briefly mentioned, is a capstone project  of LLM101N, which is a class that I'm building. 

123:02

That's a really big piece of it. But now I have to build out a lot of  

123:04

the intermediates, and then I have to hire a small  team of TAs and so on and build the entire course. 

123:11

One more thing that I would say is that many  times, when people think about education,  

123:15

they think more about what I would say is  a softer component of diffusing knowledge. 

123:21

I have something very hard and technical in mind. In my mind, education is the very difficult  

123:26

technical process of building ramps to knowledge. In my mind, nanochat is a ramp to  

123:33

knowledge because it's very simple. It's the super simplified full-stack thing. 

123:38

If you give this artifact to someone and they  look through it, they're learning a ton of stuff. 

123:43

It's giving you a lot of what I call eurekas  per second, which is understanding per second. 

123:48

That's what I want, lots of eurekas per second. So to me, this is a technical problem of  

123:52

how do we build these ramps to knowledge. So I almost think of Eureka as maybe not that  

123:58

different from some of the frontier labs  or some of the work that's going on there. 

124:03

I want to figure out how to build these  ramps very efficiently so that people are  

124:07

never stuck and everything is always  not too hard or not too trivial, and  

124:14

you have just the right material to progress. You're imagining in the short term that instead  

124:18

of a tutor being able to probe your understanding,  if you have enough self-awareness to be able to  

124:24

probe yourself, you're never going to be stuck. You can find the right answer between talking  

124:29

to the TA or talking to an LLM and  looking at the reference implementation. 

124:33

It sounds like automation or  AI is not a significant part. 

124:38

So far, the big alpha here is your  ability to explain AI codified  

124:46

in the source material of the class. That's fundamentally what the course is. 

124:51

You always have to be calibrated to  what capability exists in the industry. 

124:55

A lot of people are going to  pursue just asking ChatGPT, etc. 

124:59

But I think right now, for example, if you go to  ChatGPT and you say, teach me AI, there's no way. 

125:03

It's going to give you some slop. AI is never going to write nanochat right now. 

125:09

But nanochat is a really  useful intermediate point. 

125:13

I'm collaborating with AI  to create all this material,  

125:15

so AI is still fundamentally very helpful. Earlier on, I built CS231n at Stanford,  

125:21

which I think was the first deep learning  class at Stanford, which became very popular. 

125:27

The difference in building out 231n  then and LLM101N now is quite stark. 

125:33

I feel really empowered by the LLMs as they  exist right now, but I'm very much in the loop. 

125:37

They're helping me build the  materials, I go much faster. 

125:40

They're doing a lot of the boring stuff, etc. I feel like I'm developing the course much faster,  

125:45

and it's LLM-infused, but it's not yet at a  place where it can creatively create the content. 

125:50

I'm still there to do that. The trickiness is always  

125:53

calibrating yourself to what exists. When you imagine what is available  

125:57

through Eureka in a couple of years, it  seems like the big bottleneck is going to be  

126:02

finding Karpathys in field after field who can  convert their understanding into these ramps. 

126:09

It would change over time. Right now,  it would be hiring faculty to help work  

126:14

hand-in-hand with AI and a team of people  probably to build state-of-the-art courses. 

126:21

Over time maybe some of the TAs can become AIs. You just take all the course materials and then  

126:28

I think you could serve a very good automated  TA for the student when they have more basic  

126:33

questions or something like that. But I think you'll need faculty  

126:36

for the overall architecture of a  course and making sure that it fits. 

126:40

So I see a progression of how this will evolve. Maybe at some future point I'm not even that  

126:45

useful and AI is doing most of the  design much better than I could. 

126:47

But I still think that's going  to take some time to play out. 

126:50

Are you imagining that people who have expertise  in other fields are then contributing courses,  

126:56

or do you feel like it's quite  essential to the vision that you,  

127:01

given your understanding of how you want to  teach, are the one designing the content? 

127:07

Sal Khan is narrating all  the videos on Khan Academy. 

127:09

Are you imagining something like that? No, I will hire faculty because there  

127:12

are domains in which I'm not an expert. That's the only way to offer the state-of-the-art  

127:18

experience for the student ultimately. I do expect that I would hire faculty, but  

127:24

I will probably stick around in AI for some time. I do have something more conventional in mind for  

127:29

the current capability than what  people would probably anticipate. 

127:33

When I'm building Starfleet Academy, I do probably  imagine a physical institution, and maybe a tier  

127:38

below that a digital offering that is not the  state-of-the-art experience you would get when  

127:44

someone comes in physically full-time and we  work through material from start to end and  

127:48

make sure you understand it. That's the physical  offering. The digital offering is a bunch of stuff  

127:53

on the internet and maybe some LLM assistant. It's a bit more gimmicky in a tier below, but  

127:57

at least it's accessible to 8 billion people. I think you're basically inventing college  

128:04

from first principles for the tools that  are available today and just selecting  

128:11

for people who have the motivation and the  interest of really engaging with material. 

128:18

There's going to have to be a lot of not  just education but also re-education. 

128:21

I would love to help out there because  the jobs will probably change quite a bit. 

128:27

For example, today a lot of people are  trying to upskill in AI specifically. 

128:29

I think it's a really good  course to teach in this respect. 

128:34

Motivation-wise, before AGI motivation is very  simple to solve because people want to make money. 

128:41

This is how you make money in the industry today. Post-AGI is a lot more interesting possibly  

128:46

because if everything is automated  and there's nothing to do for anyone,  

128:49

why would anyone go to a school? I often say that pre-AGI education  

128:57

is useful. Post-AGI education is fun. In  a similar way, people go to the gym today. 

129:06

We don't need their physical strength  to manipulate heavy objects because we  

129:10

have machines that do that. They still go to the gym. 

129:12

Why do they go to the gym? Because it's fun, it's healthy,  

129:16

and you look hot when you have a six-pack. It's attractive for people to do that  

129:24

in a very deep, psychological,  evolutionary sense for humanity. 

129:30

Education will play out in the same way. You'll go to school like you go to the gym. 

129:36

Right now, not that many people learn  because learning is hard. You bounce  

129:40

from material. Some people overcome that  barrier, but for most people, it's hard. 

129:46

It's a technical problem to solve. It's a technical problem to do what my tutor  

129:50

did for me when I was learning Korean. It's tractable and buildable,  

129:53

and someone should build it. It's going to make learning  

129:55

anything trivial and desirable, and people  will do it for fun because it's trivial. 

130:00

If I had a tutor like that for any arbitrary piece  of knowledge, it's going to be so much easier to  

130:05

learn anything, and people will do it. They'll do it for the same  

130:07

reasons they go to the gym. That sounds different from using…  

130:14

So post-AGI, you're using this as  entertainment or as self-betterment. 

130:21

But it sounded like you had a vision  also that this education is relevant to  

130:25

keeping humanity in control of AI. That sounds  different. Is it entertaining for some people,  

130:30

but then empowerment for some others? How do you think about that? 

130:32

I do think eventually it's a bit of  a losing game, if that makes sense. 

130:41

It is in the long term. In the long term, which  

130:44

is longer than maybe most people in the  industry think about, it's a losing game. 

130:47

I do think people can go so far and we've barely  scratched the surface of how much a person can go. 

130:53

That's just because people are bouncing off  of material that's too easy or too hard. 

130:59

People will be able to go much further. Anyone will speak five languages because  

131:03

why not? Because it's so trivial. Anyone will know  all the basic curriculum of undergrad, et cetera. 

131:09

Now that I'm understanding the  vision, that's very interesting. 

131:14

It has a perfect analog in gym culture. I don't think 100 years  

131:18

ago anybody would be ripped. Nobody would have been able to just spontaneously  

131:22

bench two plates or three plates or something. It's very common now because of this idea of  

131:29

systematically training and lifting weights in  the gym, or systematically training to be able  

131:33

to run a marathon, which is a capability  most humans would not spontaneously have. 

131:38

You're imagining similar things for  learning across many different domains,  

131:43

much more intensely, deeply, faster. Exactly. I am betting a bit implicitly  

131:48

on some of the timelessness of human nature. It will be desirable to do all these things,  

131:58

and I think people will look up  to it as they have for millennia. 

132:03

This will continue to be true. There's some evidence of that historically. 

132:07

If you look at, for example, aristocrats, or you  look at ancient Greece or something like that,  

132:11

whenever you had little pocket environments  that were post-AGI in a certain sense, people  

132:15

have spent a lot of their time flourishing in a  certain way, either physically or cognitively. 

132:22

I feel okay about the prospects of that. If this is false and I'm wrong and we end up in a  

132:29

WALL-E or Idiocracy future, then I don't even care  if there are Dyson spheres. This is a terrible  

132:35

outcome. I really do care about humanity. Everyone has to just be  

132:41

superhuman in a certain sense. It's still a world in which that is not enabling  

132:46

us to… It's like the culture world, right? You're not fundamentally going to be able  

132:51

to transform the trajectory  of technology or influence  

132:57

decisions by your own labor or cognition alone. Maybe you can influence decisions because the AI  

133:03

is asking for your approval, but it's not because  I've invented something or I've come up with a new  

133:10

design that I'm really influencing the future. Maybe. I think there will be a transitional  

133:15

period where we are going to be  able to be in the loop and advance  

133:19

things if we understand a lot of stuff. In the long-term, that probably goes away. 

133:25

It might even become a sport. Right now you have powerlifters  

133:28

who go extreme in this direction. What is powerlifting in a cognitive era? 

133:33

Maybe it's people who are really trying  to make Olympics out of knowing stuff. 

133:39

If you have a perfect AI tutor,  maybe you can get extremely far. 

133:43

I feel that the geniuses of  today are barely scratching the  

133:48

surface of what a human mind can do, I think. I love this vision. I also feel like the person  

133:55

you have the most product-market fit with is me  because my job involves having to learn different  

134:02

subjects every week, and I am very excited. I'm similar, for that matter. A lot of people,  

134:10

for example, hate school and want to get  out of it. I really liked school. I loved  

134:15

learning things, et cetera. I wanted to stay in school. 

134:16

I stayed all the way until Ph.D. and  then they wouldn't let me stay longer,  

134:19

so I went to the industry. Roughly speaking, I love learning,  

134:25

even for the sake of learning, but I also love  learning because it's a form of empowerment and  

134:29

being useful and productive. You also made a point that  

134:32

was subtle and I want to spell it out. With what’s happened so far with online  

134:36

courses, why haven't they already enabled us to  enable every single human to know everything? 

134:44

They're just so motivation-laden because there are  no obvious on-ramps and it's so easy to get stuck. 

134:52

If you had this thing instead—like a really  good human tutor—it would just be such an  

135:00

unlock from a motivation perspective. I think so. It feels bad to bounce from  

135:04

material. It feels bad. You get negative reward  from sinking an amount of time in something and it  

135:09

doesn't pan out, or being completely bored because  what you're getting is too easy or too hard. 

135:16

When you do it properly, learning feels good. It's a technical problem to get there. 

135:21

For a while, it's going to be AI plus human  collab, and at some point, maybe it's just AI. 

135:27

Can I ask some questions about teaching well? If you had to give advice to another educator  

135:32

in another field that you're curious about to  make the kinds of YouTube tutorials you've made. 

135:40

Maybe it might be especially interesting  to talk about domains where you can't  

135:43

test someone's technical understanding by  having them code something up or something. 

135:47

What advice would you give them? That's a pretty broad topic. There are 10–20 tips  

135:54

and tricks that I semi-consciously do probably. But a lot of this comes  

136:03

from my physics background. I really, really did enjoy my physics background. 

136:06

I have a whole rant on how everyone  should learn physics in early school  

136:10

education because early school education is  not about accumulating knowledge or memory  

136:15

for tasks later in the industry. It's about booting up a brain. 

136:18

Physics uniquely boots up the brain the  best because some of the things that they  

136:22

get you to do in your brain during  physics is extremely valuable later. 

136:26

The idea of building models and abstractions  and understanding that there's a first-order  

136:31

approximation that describes most of the system,  but then there're second-order, third-order,  

136:34

fourth-order terms that may or may not be present. The idea that you're observing a very noisy  

136:39

system, but there are these fundamental  frequencies that you can abstract away. 

136:43

When a physicist walks into the class and  they say, "Assume there's a spherical cow,"  

136:48

everyone laughs at that, but this is brilliant. It's brilliant thinking that's very generalizable  

136:53

across the industry because a cow can be  approximated as a sphere in a bunch of ways. 

136:58

There's a really good book, for example, Scale. It's from a physicist talking about biology. 

137:04

Maybe this is also a book  I would recommend reading. 

137:06

You can get a lot of really interesting  approximations and chart scaling laws of animals. 

137:11

You can look at their heartbeats and  things like that, and they line up with  

137:15

the size of the animal and things like that. You can talk about an animal as a volume. 

137:20

You can talk about the heat dissipation of that,  because your heat dissipation grows as the surface  

137:25

area, which is growing as a square. But your heat creation or generation  

137:29

is growing as a cube. So I just feel like physicists  

137:33

have all the right cognitive tools to  approach problem solving in the world. 

137:36

So because of that training, I  always try to find the first-order  

137:39

terms or the second-order terms of everything. When I'm observing a system or a thing, I have a  

137:43

tangle of a web of ideas or knowledge in my mind. I'm trying to find, what is the thing that  

137:48

matters? What is the first-order component?  How can I simplify it? How can I have a  

137:52

simplest thing that shows that thing, shows it in  action, and then I can tack on the other terms? 

137:58

Maybe an example from one of my repos that I  think illustrates it well is called micrograd. 

138:03

I don't know if you're familiar with this. So micrograd is 100 lines of code  

138:06

that shows backpropagation. You can create neural networks  

138:10

out of simple operations like plus and times, et  cetera. Lego blocks of neural networks. You build  

138:14

up a computational graph and you do a forward  pass and a backward pass to get the gradients. 

138:19

Now, this is at the heart of  all neural network learning. 

138:21

So micrograd is a 100 lines of  pretty interpretable Python code,  

138:25

and it can do forward and backward arbitrary  neural networks, but not efficiently. 

138:29

So micrograd, these 100 lines of Python,  are everything you need to understand how  

138:32

neural networks train. Everything else is just  efficiency. Everything else is efficiency. There's  

138:38

a huge amount of work to get efficiency. You need your tensors, you lay them out,  

138:41

you stride them, you make sure  your kernels, orchestrating  

138:43

memory movement correctly, et cetera. It's all just efficiency, roughly speaking. 

138:47

But the core intellectual piece of neural  network training is micrograd. It's 100 lines.  

138:50

You can easily understand it. It's a recursive  application of chain rule to derive the gradient,  

138:55

which allows you to optimize any  arbitrary differentiable function. 

138:58

So I love finding these small-order terms and  serving them on a platter and discovering them. 

139:06

I feel like education is the most intellectually  interesting thing because you have a tangle  

139:11

of understanding and you're trying to lay  it out in a way that creates a ramp where  

139:16

everything only depends on the thing before it. I find that this untangling of knowledge is just  

139:21

so intellectually interesting as a cognitive task. I love doing it personally, but I just  

139:27

have a fascination with trying to lay things  out in a certain way. Maybe that helps me. 

139:31

It also makes the learning  experience so much more motivated. 

139:35

Your tutorial on the transformer begins  with bigrams, literally a lookup table from,  

139:42

"Here's the word right now, or here's  the previous word, here's the next word." 

139:46

It's literally just a lookup table. That’s the essence of it, yeah. 

139:48

It’s such a brilliant way, starting with a  lookup table and then going to a transformer.  

139:53

Each piece is motivated. Why would you add  that? Why would you add the next thing? 

139:57

You could memorize the attention formula,  but having an understanding of why every  

140:01

single piece is relevant, what problem it solves. You're presenting the pain before you present a  

140:06

solution, and how clever is that? You want to take the student  

140:08

through that progression. There are a lot of other small  

140:11

things that make it nice and engaging and  interesting. Always prompting the student.  

140:17

There's a lot of small things like that are  important and a lot of good educators will do  

140:22

this. How would you solve this? I'm not going to  present the solution before you guess. That would  

140:27

be wasteful. That's a little bit of a…I don’t  want to swear but it’s a dick move towards you  

140:34

to present you with the solution before I give  you a shot to try to come up with it yourself. 

140:38

Because if you try to come up with it yourself,  you get a better understanding of what the action  

140:46

space is, what the objective is, and then  why only this action fulfills that objective. 

140:53

You have a chance to try it yourself, and you  have an appreciation when I give you the solution. 

140:58

It maximizes the amount of  knowledge per new fact added. 

141:02

Why do you think, by default, people who are  genuine experts in their field are often bad  

141:10

at explaining it to somebody ramping up? It's the curse of knowledge and expertise. 

141:16

This is a real phenomenon, and I suffered  from it myself as much as I try not to. 

141:21

But you take certain things for granted,  and you can't put yourself in the shoes  

141:24

of new people who are just starting out. This is pervasive and happens to me as  

141:28

well. One thing that's extremely helpful.  As an example, someone was trying to show  

141:32

me a paper in biology recently, and I just  instantly had so many terrible questions. 

141:38

What I did was I used ChatGPT to ask the  questions with the paper in the context window. 

141:43

It worked through some of the simple things. Then I shared the thread to the person who  

141:49

wrote that paper or worked on that work. I felt like if they could see the dumb  

141:54

questions I had, it might help  them explain better in the future. 

142:00

For my material, I would love it if people  shared their dumb conversations with ChatGPT  

142:04

about the stuff that I've created  because it really helps me put myself  

142:07

again in the shoes of someone who's starting out. Another trick that just works astoundingly well. 

142:16

If somebody writes a paper or a blog post or an  announcement, it is in 100% of cases that just  

142:25

the narration or the transcription of how they  would explain it to you over lunch is way more,  

142:33

not only understandable, but actually  also more accurate and scientific,  

142:39

in the sense that people have a bias  to explain things in the most abstract,  

142:44

jargon-filled way possible and to clear  their throat for four paragraphs before  

142:48

they explain the central idea. But there's something about  

142:51

communicating one-on-one with a person  which compels you to just say the thing. 

142:57

Just say the thing. I saw that  tweet, I thought it was really good. 

143:00

I shared it with a bunch of people. I noticed this many, many times. 

143:06

The most prominent example is that I  remember back in my PhD days doing research. 

143:11

You read someone's paper, and you  work to understand what it's doing. 

143:15

Then you catch them, you're having beers  at the conference later, and you ask them,  

143:18

"So this paper, what were you doing? What is the  paper about?" They will just tell you these three  

143:23

sentences that perfectly captured the essence  of that paper and totally give you the idea. 

143:26

And you didn't have to read the paper. It's only when you're sitting at the table  

143:30

with a beer or something, and they're  like, "Oh yeah, the paper is just,  

143:33

you take this idea, you take that idea and try  this experiment and you try out this thing." 

143:37

They have a way of just putting it  conversationally just perfectly.  

143:40

Why isn't that the abstract? Exactly. This is coming from the  

143:47

perspective of how somebody who's trying to  explain an idea should formulate it better. 

143:51

What is your advice as a student to other  students, if you don't have a Karpathy  

143:57

who is doing the exposition of an idea? If you're reading a paper from somebody  

144:00

or reading a book, what strategies do  you employ to learn material you're  

144:07

interested in in fields you're not an expert at? I don't know that I have unique tips and tricks,  

144:13

to be honest. It's a painful process. One thing  that has always helped me quite a bit is—I  

144:26

had a small tweet about this—learning things  on demand is pretty nice. Learning depth-wise.  

144:31

I do feel you need a bit of alternation of  learning depth-wise, on demand—you're trying  

144:35

to achieve a certain project that you're going  to get a reward from—and learning breadth-wise,  

144:38

which is just, "Oh, let's do whatever 101,  and here's all the things you might need." 

144:42

Which is a lot of school—does breadth-wise  learning, like, "Oh, trust me, you'll need  

144:45

this later," that kind of stuff. Okay, I trust  you. I'll learn it because I guess I need it. 

144:50

But I love the kind of learning  where you'll get a reward out of  

144:53

doing something, and you're learning on demand. The other thing that I've found extremely helpful. 

144:59

This is an aspect where education is a bit more  selfless, but explaining things to people is a  

145:04

beautiful way to learn something more deeply. This happens to me all the time. 

145:09

It probably happens to other people too because  I realize if I don't really understand something,  

145:13

I can't explain it. I'm trying and I'm like,  

145:17

"Oh, I don't understand this." It's so annoying to come to terms with that. 

145:21

You can go back and make sure you understood it. It fills these gaps of your understanding. 

145:25

It forces you to come to terms  with them and to reconcile them. 

145:28

I love to re-explain things and people  should be doing that more as well. 

145:33

That forces you to manipulate the knowledge  and make sure that you know what you're  

145:36

talking about when you're explaining it. That's an excellent note to close on. Andrej,  

145:40

that was great. Thank you.

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Andrej Karpathy discusses the current state and future of AI, particularly focusing on agents, the decade ahead, and the evolution of AI capabilities. He contrasts the

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