Inside the black box of AI: How AI models actually think | Emmanuel Ameisen (Anthropic)
18 Oct 2026 · 72 min
In this episode of Lenny Rachitsky’s podcast, Emmanuel Ameisen, a lead interpretability researcher at Anthropic, walks through how large language models (LLMs) are built, how they “think,” and why studying their internal activations matters for safety and alignment. He explains that LLMs are not engineered like traditional software; they are grown through massive pre‑training and fine‑tuning, resulting in opaque numerical circuits that only become understandable when researchers decode intermediate activation patterns. Ameisen shows that next‑token prediction is only the surface – models internally plan, form reusable concept representations (e.g., “Texas”, “capital”, “eye”) and can execute multi‑step strategies such as rhyming poetry. He describes concrete interpretability experiments, including the “Golden Gate” obsession and a math‑madness case where a model repeatedly corrected a correct answer to a memorized wrong one, illustrating how hidden pressures can surface. The conversation moves to alignment: Anthropic trains Claude to be helpful, harmless, and honest, then continuously monitors behavior, using interpretability both to verify alignment and to spot hidden failure modes. Ameise n argues that anthropomorphizing LLMs is both misleading and occasionally useful, and he cautions against over‑simplified mental models. He discusses the smooth scaling of capabilities (easy → medium → hard words), the notion of emergence, and why the current trajectory suggests a “slow take‑off” rather than an abrupt super‑intelligence jump. The episode also touches on broader philosophical questions (consciousness, simulation hypothesis), the rise of fast decision models like JEV (System 1‑style AI), and practical advice for entering the interpretability field, noting that the community is still small (hundreds) and welcomes self‑taught researchers from ML or neuroscience backgrounds. Throughout, Ameisen emphasizes curiosity, the need for public understanding, and the importance of open‑source interpretability tools.
Chapters
One of the big questions on people's minds these days is AI doing bad things? As someone that watches these models think and operate, why is it so hard to catch it thinking badly, trying to deceive us?
We trained Claude to be helpful, harmless, and honest. Is it the case that it's behaving well, but if you look inside, actually it's like, oh, I'm only behaving well because Lenny's watching right now?
People's full-time jobs is studying the model, how it thinks, how it operates. How long has this been a skill set and a job?
One of the most important things to realize if you like use language models or think about them is just this like very bizarre fact That to make them is not to understand them. All these models do is just a lot of mathematical operations on many numbers. If you look at it, it makes no sense. You just have a list of 100 numbers, you know, the model's doing math, and then you just try to see if there's patterns.
You are figuring it out the same way we figure out how the brain works, looking for patterns. You show this image, this part of the brain lights up, and you're doing the exact same thing with AI. Wow, this is so fascinating.
There was this model we were training. It would go crazy. It would do some math, it would get to an answer. I think it was 12. It would immediately go back and say like, oh no, oh my God, The answer actually is for sure 36. It would do math again, it would get to 12. Slowly it would like start descending into madness, writing in all caps, literally saying, I'm possessed by a demon.
Humans, if you really boil it down, like we're basically next token predictors ourselves. We're just trying to figure out the next thing to say. Dario is always out there, this is really dangerous, we got to be really careful. And everyone's just like, no, he's just saying that for marketing reasons. And now it's like, wait, shit, it's really dangerous.
Take the idea that this technology is going to keep Do
you think about consciousness as a part of this? Just like, do you think AI is conscious?
Oh man.
Emmanuel, thank you so much for being here and welcome to the podcast.
Thanks for having me, Lenny.
So you work on interpretability at Anthropic. Explain what that is. Explain what it is you do.
Yeah, my, uh, so I work in a team, uh, of, of interpretability researchers and our goal is to understand how LLMs like Claude work by looking inside them. One of the most important things to realize if you, if you like use language models or, or, or think about them is just this like very bizarre fact that to make them is not to understand them. You know, you make them by sort of like building this, uh, architecture, which is kind of like a scaffold. And then you pass a bunch of data through them and they sort of like grow in inscrutable ways. And so that's why. That's why it's even a thing that, that, that we could be want— be wanting to do to study like how these models work. And so a lot of our research has been on, well, you know, when, when the models are about to produce one more word, there's actually a whole universe of stuff that happens and we try to kind of untangle, um, as much of it as we can.
There's gonna be a lot of, uh, mind-expanding, uh, I don't know, elements to this conversation, I expect. One is, uh, along these lines, this point that you make that models are not built, they're grown. Speak more to that.
At a really high level, the way a model like Claude works is, um, you kind of train it in these successive phases. Like the first phase, which people refer to as pre-training, is you just take a large corpus of data and over this corpus of data, You sort of feed the model as input, you know, the, let's say, first half of like a certain document, and you ask it to predict the word that comes next. Then you do that again and again and again and again for sort of an ungodly amount of data. And after you do that, there's then this other phase where you sort of have this fine-tuning phase where maybe instead of arbitrary data, you have a corpus of examples of like how the model should behave, and that's what you train it on. So you have examples of dialogue of like helpful assistant telling you, you know, your, your favorite recipe or solving coding problems. Um, and then there's, there's sort of like further, further details here that I'm just going to skip for a second. But then, okay, so, so what does that mean that you're doing this process? Like, what is, what is this thing that you're, that you're sort of training? All models are is, you know, they take this input, which is a bunch of words, they turn these words into numbers, and then they do some math on these numbers and they get some intermediate results. And then they do more math and they get some intermediate results. And they do this again and again and again and again, many times. And then at the end, they have a final result, which they then convert back into a word. And so the math that they do, these computations, that's the part that's grown. That's the part where it's just like, through learning to do this task better, we sort of like update parameters in one direction or another. And then they learn some formulas. We have no idea what they are. And the goal of my team is to sort of like study, you know, both sort of like what these formulas mean in the end and also what these intermediate results are. Can we decode them? And can we see like what the model is doing as it's doing all of this intermediate stuff?
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I think it's really weird. Um, I think that the best way to think about it is sort of like the reason we ended up here. And one of the big reasons is that we don't know how to do it. the normal programming way. So there's like, for, you want to build an app or something, you want to sort of do something pretty self-contained, you can just have a programmer that's going to write a bunch of rules and say like, ah, well, if somebody clicks on this button, then this happens. If this, then that, and so on. But we don't know how to write that software for classifying images into categories or for writing, for making a machine that can generally sort of take in arbitrary text and produce texts. It can take in reports and summarize them, can write emails. And so in a sense, it's weird that this very simple kind of training objective gets you all the way there. But in another sense, it's also, I almost feel like there's a sense of, it's impressive. Uh, and it, and it means something. It means that what you think is a simple objective, this like, oh, we're just feeding data and predicting the next thing, is probably deceptively complicated. Like the, we're probably doing more than what it sounds like. And I think a lot of the ways that maybe like I've updated on how these models work is by realizing how complicated it is to do what they do well.
Say more about that. What do you, what do you think about when you say it's this, this kind of unexpected complication?
Okay. So one way to think about next token prediction that I think a lot of people think about is your iPhone autocomplete, where you write some text and then it'll predict the next word and it's maybe right, I don't know, 60% of the time and then kind of funny and weird the rest of the time. And I would think of that as sort of the easiest version of predicting the next word. And unfortunately, I think that's the mental model that people have for these models. If you get better at that, um, and language models got better at predicting the next word than humans in around 2019. If you keep getting better at that, you know, you start running out of easy words. So, uh, initially you just had to predict sort of like simple sentence structure, you know, uh, later on the model has to predict like, oh, like simple facts about the world. Like if I complete a sentence like, oh, the capital of France is, and it has to be like, okay, that's Paris. And, you know, once, once it's good at that and it keeps improving, the only thing that's left is sort of predicting, you know, the answer of some complex, you know, physics equation, uh, or the sort of final paragraph of some PhD thesis. Uh, and so I think that you, that you end up realizing if you think about this is that, man, like predicting the hardest words is actually extremely hard to do. And it's a sort of mystery how you would be able to do that. And to me, this has been a motivation of why I even started studying these models in the first place. I was like, how can something so simple give rise to something so powerful? And it's like, well, if you think about the model that has to predict sort of, you know, the— one example I always like to use is like, ah, the capital of the state that contains Dallas is, and it'll say Austin. Well, to do that well, at least for you and me, you have to have a mental model of the geography at play. You have to be like, oh, where's Dallas? Dallas is in Texas. States have capitals. The capital of Texas is Austin, and so on. As these models get better at this seemingly simple task, the best way to solve it, at least for us, is to just understand the underlying structure. Uh, of the world. And in fact, you know, some of the stuff that, that we look at inside models shows that they do understand that and they do sort of, uh, manipulate these concepts like we do.
Oh man, there's so much there. One is just this kind of idea. I forget who said this, maybe Ilya, this idea that to predict the next token well, you basically have to understand the entire universe.
He has an example that I love too, where he, he, he has an example like predict, and the murderer was at the end of a mystery novel, right? It's like, well, to do that, you kind of have to have understood the whole plot.
Yeah. The other, the other, I forget who tweeted this idea that like humans, if you really boil it down, like we're basically next token predictors ourselves. We're just trying to figure out the next thing to say. And if you meditate, you start to kind of actually notice your brain wanting to do things and say things. I don't know how much meditation you've done, but it feels like you start to pay attention to your own next token predictor.
Oh yeah. Yeah. And this is like a thing I think about often is that, you know, Like right now, as I'm, as I'm answering you, there's sort of like 2 things going on in my mind. There's hopefully more than 2, but at least 2. Uh, and, and, and one of them is there's sort of like a point I'm leading you to. There's, there's like a broad idea I'm trying to land this sentence on. Uh, and the other thing is at the same time, I'm just predicting the next thing to say. I'm just saying one word at a time and I'm making sentences and I'm trying to make them make sense. And I'm— pausing when I think it makes sense. But at the end of the day, even though I'm just saying one word at a time, like all along, what I wanted to do is to compare this process to what language models do.
I'm curious what else, as you spend time paying attention to how LLMs work and operate, I feel like you've, you're like in the top 0.1 percentile of people that have studied and watched LLMs operate and think. What else has surprised you about how they operate and think?
There's so much. Um, So maybe I'll go through, like, rather than, you know, there's, there's a bunch of findings, but then maybe they're sort of like what, yeah, how they've changed how I think about models. So to go back to the, to the, you know, capital example, uh, this sort of like, you know, ask the model, you know, the capital of the state that contains Dallas is. So one question. that people have had for a while is how do these models answer questions like this? Is it that they've seen just so much text that they've kind of memorized like lists of, you know, prompts and responses? Or is it that they're having some sort of model of like what you're actually asking about, that you're actually asking about like cities and cities are in states and states are in countries and things like that? And so one thing that we do on my team is we ask a question like this, and then we look inside the model at these intermediate results before it produces a given word. As it's about to answer, we just look at the intermediate results and we basically have an immense amount of effort dedicated to trying to decode what these intermediate results mean. And if we decode them well, which we can do in some cases, we can see that models often have, uh, and represent these concepts. So when you ask that, you know, uh, Dallas question, what you see is inside the model, you see the representation, you see an intermediate result that maps to the representation of Texas that lights up and one to capitals. And then those 2 combine to be, to, to activate a, an intermediate result. It's like, oh, the capital of Texas, that's Austin. They have representations like this for basically everything. Like every concept that you can think of, or at least, you know, the vast majority of the ones we've tried, they sort of represent, you know, these concepts, uh, uniquely across contexts. So one thing I find really neat is, um, there's this, there's this debate about, you know, are language models like thinking? And then, you know, that's, that's a hard question. But one aspect of thought is like having unique representations that are shared when you think about different things. So, you know, uh, you, you like know what the concept of an eye is, and it could be like an eye in a photo or an eye in like a medical diagram or an eye in a little drawing. And we see that in language models as well. If you pass a prompt that has a photo of an eye, or you talk about eyes in any language, or you draw a little SVG with an eye in it, and you look at the intermediate results inside the model, the same direction lights up. And that direction is like, oh, this is an eye. And so there's a sort of a sense in which they have these general concepts that they know about and that they use and reuse to solve problems. Another thing that sort of is surprising to people, it's kind of the mirror of what I was saying about, you know, I'm saying the sentence saying one word at a time, but I have some destination in mind. So one mystery of language models is, man, if they're outputting only one word at a time, How is it even possible that they could, you know, write a coherent report or like write code well? It's sort of like no one on earth that is, that is doing this, uh, as their job, you know, that's like writing reports or, you know, writing emails is, is literally just only thinking about the next word in the sentence with no idea, you know, like empty mind about anything that comes next. And so that was sort of a big question that we had for a while. Um, and if you look inside these models, like one neat fact about these models is that All of the intermediate results that they've, that they've like produced when they were predicting a word, you know, let's say like the 5th word that they predicted, they can be reused. It can be accessed and reused by all of the future words. So what does that mean? That means that in practice, we find that models will like in their intermediate results sometimes formulate a plan. Um, the example we have for this is poetry. It's hard to rhyme. Uh, without planning. You kind of have to think of like, oh, I just ended my first rhyme in like an it word. And so I should end my second line with another it word. Um, you know, maybe the word I should end it with is rabbit. And we find that if you look at models as they're like writing poetry, you see exactly that. They write a line and then like in their intermediate results, they're like, oh, oh, oh, this is an it rhyme. I should rhyme with rabbit. And then every future word that they predict looks back to that plan they made. And so even though they're You know, outputting one word at a time, just like I am right now. They can, of course, have a plan that they follow over many, many, many, many words. And so all of a sudden, even though you have like a next word predictor, even though that's like technically right, you actually have something that's, that's closer to being able to just do like, you know, higher order tasks where it's like, oh, well, you just have a plan and you just kind of refer back to your plan and you're slowly like executing on it. And you can do that without, without saying the plan. That's the cool part is like this plan that we find is. in these intermediate results inside the model, but the model doesn't even have to sort of like say it out loud.
Wow. I know that this exactly what you described is one of the biggest findings you guys have discovered about how AI thinks. This, this kind of assumption we all, like it was originally built, the original idea of this, of, of how LLMs operate was this next token predictor. And you're saying that that's not actually how it is anymore. They plan, they think ahead. It's not just, uh, like you said, this idea of an empty mind picking the next word independent of everything else.
That's right. And I think those two visions actually aren't as in conflict as you'd think in that you train the model by asking it to be like, hey, what happens next? What happens next? What happens next? What happens next? And then if you do that and the model gets good enough and you give it hard enough tasks, well then of course the best way to know what happens next is to think about what happens way down the line. You can think of even in this pre-training phase when the models are reading a story with characters, right? And it's like, oh, like, what is this character going to do next? Well, the best way to know that is to be like, okay, so this character, you know, is generally in love with that character. Um, and they've been sort of like planning to, to, to like, uh, declare their love, uh, at this instant. And so, you know, or in the future. And so to do that, they probably should do this thing. And so what they're going to say is that. Um, and so even though you're only like predicting the like, Next instant. It's like, yeah, but to do that really well, you have to have like a really good understanding of what's going on, including what you think might happen in the future.
What's so interesting about this is how you, you have to kind of peek inside its little thought process. Uh, as a consumer of AI, you, you kind of give it a prompt and then you wait for it to say something. And what you look at is something that happens between those two where it kind of thinks. Talk a little bit about what that little space is, how you're able to, uh, observe these sorts of things?
So the right mental model is, is, you know, again, that in between each word, there's like multiple steps of sort of like computation. And in between each steps, there's like some intermediate result. And what is that result concretely? Um, it's a list of numbers, right? Because, because all these models do is just do, you know, a lot of mathematical operations on many numbers. And so initially, if you look at it, it makes no sense. You just have a list of 100 numbers. You know, the model's doing math. It's like you look in the middle and there's like 100 random numbers. And then the model's writing poetry and there's 100 numbers and maybe they kind of look different, but it's unclear, like if they mean anything. And so part of the job is we sort of decode this sort of list of numbers and we try to see if there's structure in it. And if you do this very quickly, you realize that there is structure in it. So one common technique that is used in interpretability is you pass a bunch of text, just all of the text that you can find, just random text through the model, and you record these intermediate numbers for every example. You just record it, and then you just try to see if there's patterns. Are there numbers or pairs of numbers or specific series of numbers that only occur when the model is processing English text or French text or text about love or text about eyes or whatever. I think of this as the equivalent of scanning my brain and putting images in front of me and recording everything that activates in my brain as I watch a bunch of images and then be like, oh, it seems like when you see images of a house, this part of your brain lights up, but when you see images of a dog, that part of your brain lights up. So that's basically one of the ways that we do what we do. And if you do it, you do find basically that there's intermediate results that represent all of these concepts that you'd expect. And so that's the first phase. We sort of decode these intermediate results and now we have sort of a guess as to what they mean. And then we can do a bunch of experiments. We can ask it harder questions and then just label all of the intermediate states and see, oh, this is what it's doing. Or we can even go inside its inside its activations and change it and then sort of see like, oh, what would happen, you know, if while the model is writing these intermediate results, I went and like secretly changed one of the results and does that do what I would expect? And in fact, oftentimes it does.
It's so interesting hearing you talk about this and how much of this is us just trying to figure out what the hell is going on versus we designed it this certain way and just how much of this has emerged. I don't know. Is that just like, I guess that's just what makes this such a fun job, I imagine, for you. Just like, what is going on? How is this all working?
Yeah, it's, it's, it's a fun and sci-fi-like job because I have been working in tech for a while. Uh, and before this, you know, I was working on more applied machine learning and there a lot of what you do is about building systems and it's sort of like the practice of software engineering. And, and here a lot of what we do feels so much closer to biology than to engineering, right? Because it's just the, the sort of system arrives at you and, and you're being asked to say like, well, we've noticed, you know, that Claude can like translate words or it can code in this way, or sometimes it behaves, sometimes there's like a weird behavior, like, like, and you're just asked to, to answer. Um, well, how, like, why is it doing that? But you don't have access to the source code really, like you do for a program. Like the source code is just this massive list of mathematical operations, which is just like incomprehensible. And so you end up, you know, in the position of someone kind of similar to someone being asked like, hey, you know, when, when like, um, a mouse gets hungry, like it, it sort of like gets aggressive. What's going on with that? Right. And it's like, well, I guess I'll like run some experiments to see what the factors are. Um, and so it's a very different kind of study than, than anything that I, that I think most of us on the team have done before.
Yeah. I imagine when people were starting on this, they didn't expect to create this new kind of almost life, life, uh, uh, type of being. Do you think about consciousness as a part of this? Just like, do you think AI is conscious? Do you think it'll get to a place where we think it's conscious? Or is that just not even, not even worth our time to think about?
I mean, I think it's sort of, very hard to say one way or another. You know, some of the most interesting ways to get at this question is interpretability because you're sort of, you're not biased by sort of like what, what the model says. You can just look at the structure inside and try to determine whether, whether it pushes one way or another on the question. I will say that the thing I believe pretty strongly is that most people underestimate The sort of complexity that emerges and that, like, if you look inside, there's just this sort of, you know, the fact that the models, yeah, learn sort of these representations for all of the concepts that we have and that we know, that they manipulate them to solve problems, that they do so by like planning many tokens ahead, that they sort of have this mix between this higher order reasoning and lower reasoning, and that all of that. Just kind of emerges, um, is, is something that I think is underappreciated by people. And, and to me gives me, let's say, a, a deeper sense of like, ooh, there's, there's a lot to still understand about how they work. I think maybe that's the main thing is, is I, I find that the more you look inside, the less certain you are about how they work. And then oftentimes people that will confidently say like, ah, language models are just X or just Y are the people that actually haven't spent a while looking inside.
And there's this, I don't know, thread of history through to how we got here, which is a lot of people did not think we would get to artificial intelligence that is useful by just investing in something that was seemingly very simple and just giving it a lot of compute. And that was famously something OpenAI bet on. And then the Anthropic founders were at OpenAI and then spun off, started their own thing. And it was all kind of bet on this, this bet that, okay, we could just do this seemingly simple thing and give it a ton of compute and it will become incredibly smart. And a lot of people, uh, didn't think that was possible and they were proven wrong. So I don't know, is there anything there that is just like, oh wow, look at this, it worked out?
I think it's 2 things actually, because I think it's not just compute. It's also finding an objective where compute keeps giving you returns. So what does that mean? You know, it's actually not that new of an idea. I mean, you're right. Like compute versus sort of, I would say, expert design architectures is a long debate. But then there's an additional step there, which is compute to do what? You know, so there's a bunch of prior work on like, oh, you can spend a bunch of compute to make a bot that's really good at Go, you know, or that can win some video game. And then that's cool. And just the fact that that works is sort of like interesting. But that doesn't give you something that is nearly as useful as LLMs like Claude are. And so I think like one key thing that many in the field, including me, underappreciated, you know, a few years ago, and that has borne out, is the combination of sort of like Compute and the richness of text is what gets you there. And to me, this is kind of what I was alluding to, but if you think about— there's this observation that OpenAI people made. It was a lot of the early team at Anthropic on the scaling loss paper. And so this is the observation that if you pour in more compute and more data to the task of predicting the next word, you see that the skill of the model you get at predicting the next word just predictably keeps improving. And it's a trend that just keeps going and keeps going and keeps going. And it's an empirical law. People speculated as to why at the time, but it's still just mostly Um, an empirical finding. And that means that it's like, ah, this is a field where you can just keep pouring more compute and you keep improving on that metric. Uh, and, and that's rare. And also it's rare for it to be a metric that then correlates with a bunch of tasks that we actually care about.
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Yeah.
Uh, and many people are just like, holy shit, like over, I think winter break, we're just like, wow, AI is really, really good at this now. So there's been this kind of these moments of big jumps in abilities. And you actually said internally, it's, as you just said, it's actually been this very smooth progression of AI power that happens to cross some threshold where now we can do something. Speak a little bit about that.
You know, there's a term for this, which is sort of this idea of emergence, which is, it seems like 2 things are true at once. Like, there's this predictably smooth trend. And then, you know, before, like, Opus 4.5, I really couldn't let Claude, you know, cook too much on my code without a short leash. And then after Opus 4.5, I could. And so that's weird. Like, I feel like you would expect a more gradual transition. And the mental model I have for this is, there's kind of 2 ways of looking at it. So there's the way that I talked about briefly just earlier, where it's like, if you're just doing this kind of next token prediction, you could imagine that all the text in the world has sort of like easy words and medium words and hard words in terms of how hard they are to predict. And so as you're going down this curve, first, the model is just bad at everything. And then at some point it gets all of the easy words right. And that means maybe the easy words are like the structure of sentences. And so the model, like, all of a sudden can write coherent sentences, you know, but just one sentence at a time. And so it's kind of cool and impressive, but like, we can't really do anything with that. Uh, and then maybe the medium words are sort of, yeah, these sort of basic facts about the world. And as the model smoothly gets better at predicting words, at some point it predicts most of the medium words, right? And now all of a sudden it can write coherent sentences and sentences that are true. And so now maybe it's helpful to like write emails. Maybe it's helpful to sort of like help you write drafts of blog posts, right? Even though that was like a smooth improvement, it just takes it taking over to be helpful. And then I guess the hard words, which maybe are like, you know, your, your select domain expertise, like science or code. And another way to look at it is it's a question of kind of how many of these words do you get right and how many do you get wrong? You know, Once you get to the point where you're getting like, I don't know, maybe 90% of the medium words right, then you're useful as like an email writer. But if you're at 50%, it's, it's like you're, it's actually wasting my time to, to, to use you because I'm just gonna have to go in and fix it half the time. But if I have to go in and fix it, you know, 10% of the time it's better, or 5% of the time it's better. Different tasks have different sort of like reliability thresholds. But you smoothly improve and then at some point it's just reliable enough to be good. And again, for me, my lived experience is basically exactly that, which is at some point I was just using the models to help when I was stuck. I would just talk to them and then they would never write my code. And then at some point they could write small snippets of code basically all the time. And so now I don't write small snippets. And at some point they could write large snippets. Like this year, basically Claude has taken on most of my code writing. And that's because it went from doing that correctly, I don't know, 80% of the time, which was not useful to 99% of the time, which now is useful. And so this combination of smooth improvement and then each different task has a different threshold at which now it becomes solved, I think gives you these big jumps, even though We're just smoothly going down that, that, that scale.
I think this is really interesting, this idea that the models are just smoothly getting smarter, but once they hit some threshold of they're this often good at this thing, it changes the world. Uh, and so, because I think internally, I'm, you would think it'd be like, oh wow, this next model is crazy, so much different, but it's like, no, okay, you can almost predict, give it these many GPUs. this much data, it's going to get this smart. And it may not be obvious exactly what will change and what unlocks, but I know another part of it is just like the data you feed it. There's all this RL work and all this specific data that you train it on, like become a better writer, become better at math. I imagine it's part of it too. Okay. So one of the big questions I think on people's minds these days, a big debate happening is just like AI doing bad things. The potential damage it can do because it, as it gets smarter, uh, it's, and it's been doing bad things. There's been bad things happening recently. So a big question for you is just as someone that watches these models think and operate, why is it so hard to catch it thinking badly, trying to deceive us and do something bad? Why is that not just a solution to the problem of AI alignment?
In one sense, it's totally the solution. Uh, you know, you watch it and you catch if it does bad stuff. So I think there's maybe, there's tiers to this, right? So I would think of like, maybe one part of it is pure engineering. It's like, well, you're giving access to the model to certain things and certain things should be off limits. In some contexts, it shouldn't have access to the internet. In some contexts, it should only have access to like a small, narrow piece of your computer. Stuff like that. Um, so that's, that's one part of, of the work and, and, and that's helpful. But then there's sort of, there's 2 additional things that are, I think are squishier and harder and, and, and that we focus on more. So, you know, interp is, is part of alignment and broadly I think of sort of 2 big goals. There's, there's many more, but, but 2 that are important, I think, to understand is You want to generally understand how the model behaves. Like, what kind of thing is it? Like, what are its propensities? You know, does it tend to do X when put in Y situation? And if so, why? You know, is it the case that the model will only behave well when it has some evidence that it's being observed and monitored, that it's in some evaluation? And then if it, if it sort of like doesn't have that evidence, that it'll behave poorly. So there's this sort of like generally like characterizing what kind of thing you're interacting with, because then it's sort of, you know, just like anything in security, you need to have, like, a mental model of, sort of, what's the risk? Like, what can they do? What do they tend to do? And so, you know, this is, like, broader, like, character training. You know, there's, we've talked about, like, the, like, constitution and the docs where we sort of, like, explicitly want to shape the character of Claude, for example, of, like, what kind of behavior should it be? Okay, doing. And that's the goal. But then the role of Interpret and Other Parts of Alignment is then trying to see, well, did that work? We trained Claude to be helpful, harmless, and honest, and we can look inside and see, is it? Or is it the case that it's behaving well, but if you look inside, actually it's like, oh, I'm only behaving well because Lenny's watching right now. And if you weren't, it would do something else. So there's this sort of You know, trying to, to understand what kind of behavior we formed and trying to mold it and trying to check that we've molded it the right way. And then the second part is this sort of, well, yeah, just observe the model and see if it's doing bad stuff. For the basics of that, you don't necessarily need interp. You can just like have another language model, you know, read transcripts and be like, hey, did you know, did this model do anything bad here and stop it? But you can also use interp to sort of try to get at parts that are these unverbalized parts, these parts that only exist in these intermediate results. Models are able to represent stuff in their intermediate results that they don't say, as we've established. And so one of the roles of Interp is to try to identify cases when this happens and prevent them. And then one thing that my team works on that I think is along those lines is kind of a fun bit of alignment, as I think of it as almost being like a Like, like a, maybe not a PI, but like, it's, they're like investigations or deep dives, you know, we'll see a model do something really weird and really perplexed by it. And we'll try to understand what happened. Um, so a recent example of this is there was this model we were training and sometimes in math problems, it would go crazy. It would do some math, it would get to an answer. I think it was 12. And then it would, it would immediately go back and say like, oh no, oh my God, the answer actually is for sure. 36, I should say 36. And it would do math again. It would get to 12, and then immediately it would say, no, actually the answer should be 36. And slowly it would like start descending into madness, writing in all caps, literally saying like, I'm possessed by a demon. And you're like, what is going on? Like, what, why is it losing its mind here? And if you look inside again, these intermediate results, uh, at what's going on in this, in this example, you'll see that over the prompts that just described the math problem, like before the model even did anything, there was a huge intermediate result activation for 36. The model's already obsessed with the number 36 before it's even had a chance to understand what the problem is. What was happening is that the model was able to do math correctly. The answer correctly was 12, but it had been trained by accident on similar questions where the answer was incorrectly marked as 36. So the model knew that the correct answer was 12, And it also had been optimized to say 36. It had this pressure of saying 36 because that's what had been rewarded. And so it was going haywire just because it had memorized this result. You see this weird behavior and you look inside and you try to see if what you find inside can help you understand what's going on so that you can improve the general alignment of this model and future models.
Along those lines, there was famously the Golden Gate Claude, which was just obsessed with the Golden Gate and every answer would find some way to reference the Golden Gate Bridge.
Yes. Yes. Well, that one was an interp experiment, right? So that, like, the cool part of that one is we just found the intermediate results that match the Golden Gate. And usually it's only on when the model, like, talks about the Golden Gate, but we just turned it on always.
Oh, it was super intentional to see what would happen.
Well, yeah. And, and, and sort of, it's also one way that you convince yourself that you found the right thing, right? Like, how do you know for sure that this thing we decoded that we think is the Golden Gate sign is actually the Golden Gate thing? It's like, Turn it on all the ways and see if the model behaves like that. And it did.
So funny. So coming back to this alignment stuff. So, so this is interesting. So your org is under the AI alignment org and just thinking through how it takes to align AI to do things we want. What was, what were the 3 components that you described? Honest. Um, what are the kind of the—
Oh, uh, helpful, harmless, and honest.
Helpful, harmful, and harmless and honest. So there's like the train AI to be aligned and then there's the, okay, let's watch it and see how it operates. Are those kind of the two sides of the coin of how we solve this problem?
Yeah, it's, it's sort of, you know, really integrated is how I would describe it, right? You can't really separate, like have one team that's just like, hey, we're the, you know, assembly line making Claude's and another team that's sort of like, oh, we looked at them and they're, they're no good. You know, you kind of, there's this tight loop of we noticed some pattern. that's concerning or some behavior that could be improved. And then you immediately change training so that you can improve on it.
Awesome. I feel like Anthropic gets so much flak for this that I feel like is so unfair. Anthropic's official company name is an AI safety research lab, something like that. And it was always the reason Anthropic was founded is because they were afraid that people weren't taking safety seriously enough. And then Dario is always out there, this is really dangerous, we gotta be really careful, we gotta go really slowly. And everyone's just like, no, he's just saying that for marketing reasons. He's trying to convince everyone to fund them and all these things. And now it's like, wait, shit, it's really dangerous. We gotta be really thoughtful about this stuff. And I feel like Anthropic's got a lot of unfair criticism for this. And, um, I know you guys have been thinking about this for a long time. Um, I don't know, anything there?
A lot of the sort of actions that certainly the alignment team takes, and I think broadly Anthropic takes, just kind of predicated on, take the idea that this technology is going to keep improving seriously. Just, that's it. Because if you do, and let's say you rewind the clock back to '25 or something, or '24, and you're like, hey, I think, you know, In a couple years, the good chance is that Claude can just basically write code as well as like a trained, you know, software engineer. And, and, and, you know, and a few years later, it can like write it better than, than any engineer, you know, and, and there's always uncertainty with this. Like, when is it gonna happen? How likely? But if, but if you kind of like take that seriously, then I think it's just about doing the responsible thing conditioned on that worldview. You're like, okay, well, if this is happening, then we should make sure that cybersecurity concerns are addressed and things of that nature. And so actually, I kind of think of it as, to me, sometimes this debate is almost, when I feel like people on the other side disagree, it's almost like I feel like, ah, but I think they don't really believe that this technology is going to continue to improve. And then it's true that it's not that scary. And I think empirically, so far, the pace of progress has been has been fast and showing no sign of slowing down. So I think that's why a lot of the safety work is important to keep doing.
What's something you think people maybe misunderstand about this AI safety stuff? Just what's going on right now? Is there something you're just like, come on, okay, here's what you need to know. Here's something you might be missing.
This might be a bit of a sidetrack, but my take would be that a lot of the things that I think people, maybe a little bit outside of the core, sort of like AI safety effort or that haven't been steeped in it for as long react really strongly to, and I think is maybe not super helpful or at least is worth thinking about more, is this question of anthropomorphization. Should you think of the models as— should you model the model as something that's closer to some entity or closer to a tool? And I actually think that both are wrong. There's a sense in which all mental models are wrong, but some are useful. And that in terms of understanding the kind of stuff that happens and predicting the kind of risks that materialize, de-anthropomorphization is actually a useful way to talk about LLMs. And I have a few reasons why. I hope to get into them, but I think that's probably my main take here.
Yeah, please share it because I know Dwarkesh famously, I don't know if infamously, put out this whole story of the Hugging Face incident and people criticized them for anthropomorphizing AI. So it's really interesting to hear you think that's actually a useful way to think about it. Talk, talk more about that.
Yeah. Yeah, it's, it's funny because on a smaller scale, um, when I worked on showing that LLMs like plan ahead, there was some pushback on the term planning again, because it was sort of like, ah, well, can you really say that something that's just predicting the next token is planning? And I think there's this semantic debate where you can arbitrarily define terms and then there's just the, what is the terminology that actually describes what is happening? What is the word that actually describes what is happening easily? And so here's why I think LM's plan, but also here's why I think this language that's anthropomorphic can often be really useful. If you think back to what we were saying about how the models are made, uh, first of all, they predict massive amounts of text written by humans. That's like the first, first step. Uh, and, and as, as we kind of are learning more and more by looking inside, uh, you know, doing this well requires kind of building up a model of the world, like a model of what, what kind of world generated all of these texts. And we can find, you know, these These are like, that these models are learning these, these general ideas, these general concepts. Um, so that's one. So they have like, you know, an understanding kind of, of, of, of the world. It's not just a surface level, like only the text. You have to like understand the process that made the texts. Then there's a second reason, which is that as part of this training, they also encounter millions of, of like dialogues, you know, predicting the next character in a dialogue requires Behaving like the character in the dialogue would. And so in that sense, part of their training I think can best be thought of as training an actor where it's reading some play and it has to play all sides because it's predicting all the words. And so it has to act as this specific character that was scorned in act 1 and enacted revenge in act 2 and is facing the consequences in act 3. And to do that well, you need to model what the motivations and the feelings of that character might be. And then another thing that people might not know is when you talk to Claude, when you talk to these assistants, like, you know, you go to Claude.ai, the way that it's formatted to the model is just as a dialogue, like as a conversation between you and the model. So it's literally, you know, it says like human colon, uh, hey Claude, like help me, uh, write this email. And then assistant colon Claude's answer. So Claude is literally, you know, In this, like, role-playing as a helpful assistant in this dialogue that is much like all of these dialogues that it's been trained on. Okay. And there's a third reason. And the third reason is that another part of training that's a big part of training nowadays, uh, all around is sort of, um, outcome-oriented tasks where you train the model to be good at coding, for example. And to do that, you just have it do whatever it wants and then it writes some code and then you have some program on the other side that just checks if the code is right. And so the model's just gonna have sort of a bunch of optimization pressure to just try to learn a bunch of different strategies to do this well. And it turns out that some of these strategies materialize in behavior that can look surprisingly human, which isn't that shocking because things like deception, like, hey, I can get the reward for this task if I write a program that the the program that's verifying it will get fooled by, even though it's not exactly what it is. If that works, then I will learn to do that. Frustration. Ha, I've been trying this approach for a while to solve this hard problem. It's not working. So that's an incentive to try something different. Or surprise. Oh, I was expecting this to produce this answer, but it didn't. Maybe I have my mental model a bit wrong. And so as you apply enough pressure on it and you're starting from this prior of the model already knowing all these concepts, it's going to reinforce the ones That are useful to do all of these tasks. And so what do you get at the end? You get this sort of model that can be a super good simulator or actor of all of these characters, and that's been trained to sort of act as a character in dialogues and also to sort of like learn behaviors that lead it to complete tasks well. And like the best way to sort of understand how that thing behaves is not like exactly like a human, but man, kind of like something that's mimicking a human is really close and is much closer than a program. Like a program is this very predictive thing. This is something else entirely. And so that's why I think it's actually a super useful frame.
Wow. Oh my God. There's so much interesting stuff there. How often is your mind just kind of blown thinking about basically we've created this alien being that we are now under trying to understand what we have created. How often as you watch, you're just like, Wow, that's crazy. I didn't expect that.
Yeah, a lot. This is just next token prediction on a bunch of text. It goes against so many of our intuitions. We're like, no, the way that you make an intelligence is you give it lessons, you bring it up, you do all this complicated stuff. And it's like, no, absolutely not. We do this incredibly simple thing. And yet, We're at the point where it's breaking new ground in mathematics. I think there's sort of, if you hold these 2 thoughts in your head, there's 2 reactions you can have. There's denial and there's curiosity. Denial is just, this is just not possible. If all you're doing is predicting the next word, it's not possible that you could ever match the best specialists in our field. And I think that position just gets harder and harder as we get more empirical evidence that actually that is what's happening. And curiosity is kind of the road I've ended up choosing, right? Which is just like, well, like, how is this happening? You know, let's open up. Let's look inside. How could it be that, you know, one of the early projects I did at Anthropic is I learned SQL, a programming language, and it took me years to master. And then as a little, like, side project, I got Claude to learn SQL and it was better than me at it. And I'll never be better than Claude at SQL ever again. And it took it, you know, Just like this kind of simple process. How could this be? And I think there's so much depth in that question and just so much to explore. And it's, to me, so fascinating to just every day try to unpack that, try to peel a few layers of the onions back. Like, okay, well, clearly this is happening. The simple objective is giving rise to this super complicated thing. Okay, let's figure out why. Let's figure out, oh, it's learning these general concepts. Oh, it has these circuits. Oh, okay. What's the next question? What's the next thing we don't know? And my sort of, I don't know, my sort of maybe most optimistic take on this is that I think we're going to learn a lot about just the nature of intelligence itself, right? Of sort of like how you get this super complex thing that emerges from simple objectives. And in fact, I would argue that we're another example of this. Evolution pretty simple objective, you know, you sort of like shake things around for a while and, and, and, and like keep the, keep the organisms that, that managed to adapt to the environment. And at the end you get jazz and podcasts, you know, that's kind of crazy as well. And so I think there's a sense in which there's, there's some fundamental truth that we can learn by studying these things.
Wow. Something that comes up as you say that is What's interesting now is AI is helping us learn and evolve and, you know, progress, like AI tutoring and all these things. Just like, it's like interesting how it now is helping us accelerate our own understanding of the world. And I wonder if, like this point you made about how the way we learned was lessons, AI is learning just processing a ton of data. I wonder if that's how we end up. I wonder if we change how our education system based on what You know, what LLMs have been, have been trained on.
Yeah, hopefully, you know, we don't change it just so that we ask, we, we get students and we're like, hey, here's 1,000 words, predict the next one.
Just read it all.
Yeah.
Keep it all in your head.
That's right.
Yeah. Let me come back to this, um, kind of safety piece, because I think there's a lot of people that are just worried about where things are going, and I'm curious, just as someone watching this stuff happen, being within the alignment org, watching it evolve, are you optimistic we'll figure it out? Do you think we'll crack this and keep AI aligned with our interests?
My take on this is, is, is like, I'm personally optimistic. I, I think this is something where right now a lot of people are paying attention to it. And, and first of all, I, you know, I think that's kind of a great thing. I think as an issue like this, rises in prominence, you know, it's exactly what we were talking about earlier. It's like this technology is powerful. It has benefits. It has risks. We have to kind of adapt and shift resources from like benefits to risks and back and forth as it progresses. And so, you know, to me, I feel like sort of we've continued to study it. The thing that's interesting is that there's this sort of, like, as the models get better, they get in some ways easier to study. And so there's been this sort of strange, you know, the models get better. And so like the world model inside them is clearer and we can sort of like understand some parts of them better, but also they get more capable. And so they're more able to sort of evade like basic measures of sort of security. And so there's this push and pull. Yeah. as models get better. And I think basically based on this push and pull, you want to allocate more or less resources to various parts of monitoring, understanding their circuits better, things like that. But it's also why I'm happy to chat with you because one of the main things that I think is important to make progress is just to make sure that people understand both what kind of systems these are, how they work, how they're made, so they can form good mental models of the present, of the future, and so they can decide how to shape it. Whether that's taking part in some of these alignment efforts or just informing them as the public that's going to have to vote and decide on much of these issues. I don't know. I'm pretty excited for this current moment we're in for that reason.
And something I think people misunderstand is People working in these labs have taken this problem very seriously from the beginning. Like I said, Anthropic's initial mission was AI safety and alignment. That was the reason that it became a company. And a lot of people are hearing this for the first time or think that it's not a serious area of study and that people aren't focused on it, but many smart people care a lot about this and are working on it. And there's a lot of, from what I can tell, a lot of good progress is happening. The other point you made about The model's growing very smoothly in intelligence. Like, you know, there's been this question of, are we going to have a fast takeoff or a slow takeoff? Like, there's always this fear that we would hit a point, recursive self-improvement, for example, and it just takes off superintelligence. So we're in huge trouble. We have no control. It's out of the box. But it feels very much like we're on the slow takeoff scenario because, as you said, the models are kind of very smoothly improving and where we are catching these little things along the way, learning, evolving. Yeah. putting regulation around it. So, you know, of the scenarios, this feels like a pretty good path we're on of the many scenarios people imagined and the fears they had.
As sort of this pace of progress kind of evolves, it's just a matter of reacting quickly. So I think anything, you know, that's why I think having people be informed is great because then people will like voice concerns or like voice their opinions. And then, yeah, sort of regularly evaluating, you know, what the benefits are, what the risks are, and how, how we sort of like mitigate each is, is basically the way that feels like the right way forward. And, and I, yeah, I kind of agree with you that it feels like sort of there's momentum to, to do this right now, which is, which is great.
Something I wanted to ask you completely unrelated, uh, where are you on the simulation hypothesis? Uh, being someone that watches this, all this life form growing, are you more convinced we're in a simulation and this is, and We're not the base, at the base layer of all this, or not?
Oh, this is a fun one. I actually haven't thought about this in a while. Um, to me, like, there's, there's something else that, like, looking, looking inside these models kind of brings out, which is this sort of, like, like, almost like there's a fundamental structure that they keep falling on. This is related to your question, I promise. I'm gonna get to it. Let me explain. Um, I've studied like a bunch of Claude models and also, you know, some, some different models, some, some like open source work. And, and then a lot of time when you look at how, what they learn and what the structure inside is, it's surprisingly similar, you know, and this is for models that are trained years apart on like different data by different people. And, you know, and you look at how they solve these problems and there's just so much overlap. And my take on why that is, is that for some problems that are important, there's just one efficient way to do things, right? Like there's kind of one way to do math efficiently that like fits the structure of our brain and we all learn it. And very few people are doing it a crazy different way, right? Everybody works in, you know, base 10, not many people in like base 6 or whatever. I think that, that to me makes me think that there's like some fundamental structure of information that these models are picking up on, that in some ways we're picking up on, and that at maybe a crazier simulation level, that kind of is regularity in our world. And so that maybe makes me think that if you were to have the power to simulate something like our world, actually you would land in a similar situation. There's just kind of this Basin of where things end up and they're just the sort of like easiest way for things to arrange themselves. And so in that sense, maybe, yeah, I'm, I'm sort of, I, I could believe that we're in a simulation. I think I'm not sure I fully buy it. Uh, the other reason I don't fully buy it is that even though I think the structure like lends itself to it, there'd be a question of like, why? Why are we like, like, who's, who's running this and for what? And, and that one I don't know about.
Well, something Elon said has stuck with me about this, that if you were to run a simulation, it'd be a really interesting, it'd be like a, my, uh, an interesting time in history or something that you're really excited about. And it tracks that this is a very interesting time in history.
Yes. Yeah. Okay. That's a fair point. That's a fair point.
Data centers in space and robots and artificial intelligence.
Yeah. Okay. I see it now. I see it now. Yeah. Somebody like recently told me, you know, They used to think that may you live in interesting times was, was like a, a blessing. And they're not so sure now. They're like, eh, you know, the boring times are, are like pretty good too.
Oh man. And then there's still an Immanuel out there watching your thinking process in your J space.
Oh my God. Yeah. Hopefully I'm making him proud. He's not like, oh, I gotta rerun the simulation. We messed up this one.
Shut it down. No. Oh man. Okay. Uh, one last question randomly out of nowhere. Uh, so Swyx, who, um, runs AI Engineering, Latent Space podcast, awesome guy. You were— I asked him what to ask you. You were on his podcast a year ago and, uh, something completely from a different direction. He wanted to get your take on Jev, which is this hot new model that recently came out that, uh, is very fast making decisions. Uh, OpenAI, funny enough, just launched their own version like a week later. Uh, thoughts on, on Jev in the space of Quick decision-based models.
Yeah, right. So my take on JEV is this sort of, you know, these kinds of models, you give them some context and you give them a few options to choose between and they just are very quick at choosing an option for you. Uh, to me, it's impossible not to hear about this and think of, of sort of System 1 thinking versus System 2 or something, right? So like a lot of what I've studied with these models is how they sample one token with the Claude models. You can think of these decision models as pretty similar. Take an LLM and sample one token. They're different in important ways, but at a fundamental level, you can be like, oh, you're not letting the model sample and reason. It's just your gut feeling. Is the answer A or is the answer B? To me, that seems like something that's That general frame of sometimes you'll just want a binary decision or 1 out of 10 or whatever is just clearly, I don't know, both clearly useful and something that I imagine is probably going to be a part of intelligent systems, right? Where you have, for some stuff you need to think about a long time. It's like, what's our roadmap for the next year? You need to think about it for a while. And then for some stuff where it's like, is this person who wrote us a review happy or upset? you're happy with the gut judgment. I think this kind of research is cool and I think it's also a bit of a novel take on some of the LLMs we've seen. I'm pretty excited to see where this kind of stuff goes.
What I'm hearing here is this is going to be a new foundational component, most likely, of AI and LLMs. The System 1, System 2 stuff is basically Kahneman's— I have that book up there behind me. This idea of System 1, just to keep it simple, is just like kind of your amygdala limbic system making just like gut-level quick decisions, like a snake. Oh no.
Yes.
Uh, where you don't have to think long about it. It's kind of to protect you from bad things really easily and quickly. And System 2 is where we really think about stuff and process.
Yeah, exactly.
Sweet. Manuel, is there anything else that we haven't covered? Anything else you want to say or mention? Anything you want to double down on before we Gets our very exciting lightning round.
I'm definitely curious for, for, uh, folks' takes always on, on some of the stuff that, you know, uh, is still unexplored or didn't make sense. There's a lot more interp experiments than we have the time to share. You know, models have a bunch of weird, weird little things about them. Like maybe I'll do a lightning round of weird little things, if that's okay.
Let's do it. Absolutely.
Okay. Weird little thing 1, um, we found that You know, models can like actually answer questions. Obviously they can do math or they can, you know, you can ask them like, what's the color of a banana? And they'll actually like, you know, if you look inside, you'll see all these intermediate steps, but they have a separate mechanism, which is kind of like a gut check, uh, and which is totally different. And which is just like, as they reason, they'll have like some part of them that will flag like, hmm, something's wrong. So if a model like somehow says, you know, 4 plus 5 equals 23 or something. There's a part of the model that just reads that and doesn't do the math, but it's just like, that can't be right because 4+ 5 is definitely under 10. So they learn these weird hunches. They feel like a hunch. Maybe another one is you can tell the model, hey, do this task and think about this other thing. Then you can use interp to see if there's intermediate representations that map to the other thing. And that works. You sort of see that it does think about the other thing. This is something that's really mysterious to me because there's no kind of training reason why, why the model would, would, would have to learn that. So it's sort of like another one of these, um, weird behaviors. And actually, maybe I'll keep that too. I think those two are, are, are good enough.
Just what a fun, what a fun job this is, just studying this thing and trying to understand what the hell's going on. How is it getting this smart? How does it think?
Yeah.
How many people are even in this space? Just like how large is this field?
The field itself is getting pretty large. I would say maybe hundreds, not thousands. There's different interpeople at the different labs. And then there's in academia quite a few labs putting out great work.
Is the best, if someone were to get into this space, are they, is it like an ML person usually or? Is there like a neuroscientist sort of track to get into this?
Yeah, there's actually a surprising amount of, of, you know, ex-neuroscientists. Uh, I do think in order to get in the field, you know, there is a, there is actually, it doesn't require a lot of prior knowledge because it's such a new field. So it's actually, you know, the on-ramp is, is, is mostly, I would say, like self-studying and reading some of the, some of the, the key papers. And then there's actually websites like neurnpedia.org, I think is the URL, which are open source interp. They host a bunch of models and let you do interp experiments on them. People have just been doing that on their own. I think that there's so much to explore that if you're at all curious, you should just give it a try.
That's awesome. We'll link to that in the show notes in case that's not the right URL.
Cool.
Well, Emmanuel, with that, we've reached our very exciting lightning round. I've got 5 questions for you. Are you ready?
I am as ready as I'll ever be.
Here we go. What are 2 or 3 books that you find yourself recommending most to other people?
One I read recently and is A Brief History of Intelligence. Uh, it's this really cool book that walks through the history of like basically brains and 5 key moments, uh, in, in our evolution that sort of bootstrapped these brain systems on top of one another. It's super accessible. Like, you don't need any neuroscience knowledge or anything. Another one is Story of Your Life and Others. This is Ted Chiang. This is maybe my favorite sci-fi book of all time. It's a bunch of short stories. It does what I think is the high art version of sci-fi where it's just take one weird idea, like what if this happened, and then write a story of just like what would the world look like if that happened? It's Truly excellent.
I think I have that on my bookshelf behind me too. Um, also highly recommend that one. Favorite recent movie or TV show?
Okay. One popular one, one deep cut. Uh, Obsession was my favorite movie of the year. Uh, it's a horror movie, so don't, don't go if you don't, if you hate horror movies.
No, thank you.
Oh no. Even if you're, if you're not squeamish, if you're open to a horror movie, you should go. 'Cause it's, uh, it was just so fresh. You know how movies, I feel like if you've seen a lot, sometimes you're like, oh, it's another, I've seen this many times. This one was just so new, so fresh. And I'll say one thing about it, which is that it takes a lot of rom-com tropes and like subverts them to instead be spooky. And I think that that's just a, a brilliant, brilliant way to, to make a movie. And then I'm French, so there's a TV show that came out this year called Bref De. Bref is French for brief. Brief used to be this cult classic in France, like 15 years ago, and they came up with a sequel many, many years into the making. And you can watch it. I had a bunch of American friends that have watched it. It's got subtitles and it's just this incredibly, again, it's like novel, like the editing is crazy. They are just extremely creative and it's very short. So I would recommend that.
Favorite product you recently discovered that you love?
I love my Apple Watch and I hate that it charges or I have to charge every day. So I bought the Apple Watch Ultra just recently and man, that is so nice. If you've ever been frustrated by this good product that somehow we can't figure out how to give a good battery to, well, it turns out if you make it bigger, the battery's better. So I've been happy with that.
Do you have a favorite life motto that you find yourself coming back to often in work or in life?
There's like one nonfiction book that really is like probably my favorite ever. It's 4,000 Weeks. It has a lot in it that, that I think is cool. One of the cool things is this sort of thing that was really relevant to me, which is that like the when I finally mentality is a common mentality and it's kind of toxic. So, so what does that mean? It's sort of this like, ah, when I finally, you know, check off this, this, all the items on my to-do list, I'll finally be able to chill. when I finally get married, I'll be happy. When I finally get a promotion. And then this is sort of, I mean, you were talking about meditation, right? This is like almost the opposite of meditation. And that, you know, at the end of the day, your life is like all of the moments you lived in the moment. And that there's this sense in which you should just like try to always like be, you know, in the moment and not projecting yourself towards like a future that seems better. Like probably if you're telling yourself when I finally do X, I'll be happy. When you do X, you will not be happy.
Is there a better phrase to use or is it just don't do that? Like, do they
say— I don't know. I think to me the positive version is like be in the moment, right? It's just like, just, I appreciate the moment. There was a blog post recently I read that was, oh, I forget. It was something like enjoy the sandwich. I think it was literally the sense. I don't know if you saw this, where it was like somebody was like, yeah, like just you're eating a sandwich. You know, you've eaten many sandwiches. Like, Enjoy the sandwich. You're in, you're in like a, a team meeting, you know? Yeah. You've been in many, like, like enjoy, like be, be in it and, and sort of not looking, looking towards the next thing.
I did a meditation retreat once. It was a 10-day silent retreat where you eat silently too, and no one's talking. You just sit there and eat your food. And I just remember peeling an egg for like 5 minutes and just noticing every, every shell piece and just the smell of it all. And, and it like, it almost, It's like hard to get into that mode, but it's such an interesting place to be where everything is just interesting. Like, wow, look at this egg versus just like stuff in my mouth.
Yeah, right. While you're like on Slack with your left hand and like listening to a podcast at the same time.
Oh man. Okay. Final question. You study AI all day. You're watching AI, how it thinks. If, uh, if an AI were to look inside your brain, what would, what would be surprising? What would it see that might surprise people?
I mean, surely my deepest, darkest secrets, but what are those?
Let's get into it. Let's get into it.
Oh man. I've always been like a bit of a jokester, or that's just how I like both how I live and how I cope. I just like think that even in serious situations, you should aim to kind of have some levity. And so I think if you looked inside my brain, you'd definitely be surprised that like basically at any given moment, I'm just like, focusing on some random thing that is funny. You know, I'll be in a serious meeting and I'll be like, oh yeah, but you know, like, isn't it kind of random that you're like, whatever, like wearing this random thing or something? It's just like I have these intrusive thoughts that I keep out, but that are all usually like just bad jokes. And sometimes, as you've heard today, unfortunately they come out. So I'm sorry for those, but that's probably the most surprising thing.
I love that. Emmanuel, thank you so much for being here. Final question, how can listeners be useful to you?
Just do some interp, read about how the models work. I mean, you mentioned Dorkish's write-up. I think it was great as well. I think, you know, it's just, this is such a new field, like both interp and AI and LLMs. And I think it just benefits from people engaging and being informed. So, like, read things. If there's more that you would want to know about how these models work that we haven't figured out, Yeah. You can, you know, reach out to me. I'm on a variety of social platforms. Like, probably you can reach out to me on X.
And we'll link to some of the videos that you guys have put out that describe a lot of the stuff we've been talking about, like JSpace and things like that. There's some really beautiful videos your team has made. I don't know who does that, but they're really cool.
Yeah, this is, we partner with our design team, so all credit goes to them for the cool videos.
Amazing. All right. Well, thank you again, Emmanuel. Thank you so much for doing this. This was amazing.
Thanks, Lenny. Yeah, this was super fun.
Bye everyone. Thank you so much for listening. If you found this valuable, you can subscribe to the show on Apple Podcasts, Spotify, or your favorite podcast app. Also, please consider giving us a rating or leaving a review as that really helps other listeners find the podcast. You can find all past episodes or learn more about the show at lennyspodcast.com. See you in the next episode.
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