LLMs being "Language Models" means they model language, it doesn't mean they "model the world with language".
On the contrary, modeling language requires you to also model the world, but that's in the hidden state, and not using language.
LLMs being "Language Models" means they model language, it doesn't mean they "model the world with language".
On the contrary, modeling language requires you to also model the world, but that's in the hidden state, and not using language.
LLMs can only model tokens, and tokens are produced by humans trying to model the world. Tokenized models are NOT the only kinds of models humans can produce (we can have visual, kinaesthetic, tactile, gustatory, and all sorts of sensory, non-linguistic models of the world).
LLMs are trained on tokenizations of text, and most of that text is humans attempting to translate their various models of the world into tokenized form. I.e. humans make tokenized models of their actual models (which are still just messy models of the world), and this is what LLMs are trained on.
So, do "LLMS model the world with language"? Well, they are constrained in that they can only model the world that is already modeled by language (generally: tokenized). So the "with" here is vague. But patterns encoded in the hidden state are still patterns of tokens.
Humans can have models that are much more complicated than patterns of tokens. Non-LLM models (e.g. models connected to sensors, such as those in self-driving vehicles, and VLMs) can use more than simple linguistic tokens to model the world, but LLMs are deeply constrained relative to humans, in this very specific sense.
But I know very little about this.
This is mostly incorrect, unless you mean "they both become tensor / vector representations (embeddings)". But these vector representations are not comparable.
E.g. if you have a VLM with a frozen dual-backbone architecture (say, a vision transformer encoder trained on images, and an LLM encoder backbone pre-trained in the usual LLM way), then even if, for example, you design this architecture so the embedding vectors produced by each encoder have the same shape, to be combined via another component, e.g. some unified transformer, it will not be the case that e.g. the cosine similarity between an image embedding and a text embedding is a meaningful quantity (it will just be random nonsense). The representations from each backbone are not identical, and the semantic structure of each space is almost certainly very different.
They present a statistical model of an existing corpus of text.
If this existing corpus includes useful information it can regurgitate that.
It cannot, however, synthesize new facts by combining information from this corpus.
The strongest thing you could feasibly claim is that the corpus itself models the world, and that the LLM is a surrogate for that model. But this is not true either. The corpus of human produced text is messy, containing mistakes, contradictions, and propaganda; it has to be interpreted by someone with an actual world model (a human) in order for it to be applied to any scrnario; your typical corpus is also biased towards internet discussions, the english language, and western prejudices.
The bet OpenAI has made is that if this is the optimal final form, then given enough data and training, gradient descent will eventually build it. And I don't think that's entirely unreasonable, even if we haven't quite reached that point yet. The issues are more in how language is an imperfect description of the world. LLMs seems to be able to navigate the mistakes, contradictions and propaganda with some success, but fail at things like spatial awareness. That's why OpenAI is pushing image models and 3d world models, despite making very little money from them: they are working towards LLMs with more complete world models unchained by language
I'm not sure if they are on the right track, but from a theoretical point I don't see an inherent fault
First, the subjectivity of language.
1) People only speak or write down information that needs to be added to a base "world model" that a listener or receiver already has. This context is extremely important to any form of communication and is entirely missing when you train a pure language model. The subjective experience required to parse the text is missing.
2) When people produce text, there is always a motive to do so which influences the contents of the text. This subjective information component of producing the text is interpreted no different from any "world model" information.
A world model should be as objective as possible. Using language, the most subjective form of information is a bad fit.
The other issue in this argument is that you're inverting the implication. You say an accurate world model will produce the best word model, but then suddenly this is used to imply that any good word model is a useful world model. This does not compute.
Which companies try to address with image, video and 3d world capabilities, to add that missing context. "Video generation as world simulators" is what OpenAI once called it
> When people produce text, there is always a motive to do so which influences the contents of the text. This subjective information component of producing the text is interpreted no different from any "world model" information.
Obviously you need not only a model of the world, but also of the messenger, so you can understand how subjective information relates to the speaker and the world. Similar to what humans do
> The other issue in this argument is that you're inverting the implication. You say an accurate world model will produce the best word model, but then suddenly this is used to imply that any good word model is a useful world model. This does not compute
The argument is that training neural networks with gradient descent is a universal optimizer. It will always try to find weights for the neural network that cause it to produce the "best" results on your training data, in the constraints of your architecture, training time, random chance, etc. If you give it training data that is best solved by learning basic math, with a neural architecture that is capable of learning basic math, gradient descent will teach your model basic math. Give it enough training data that is best solved with a solution that involves building a world model, and a neural network that is capable of encoding this, then gradient descent will eventually create a world model.
Of course in reality this is not simple. Gradient descent loves to "cheat" and find unexpected shortcuts that apply to your training data but don't generalize. Just because it should be principally possible doesn't mean it's easy, but it's at least a path that can be monetized along the way, and for the moment seems to have captivated investors
Let me illustrate the point using a different argument with the same structure: 1) The best professional chefs are excellent at cutting onions 2) Therefore, if we train a model to cuy onions using gradient descent, that model will be a very good profrssional chef
2) clearly does not follow from 1)
Note humans generate their own non-complete world model. For example there are sounds and colors we don’t hear or see. Odors we don’t smell. Etc…. We have an incomplete model of the world, but we still have a model that proves useful for us.
This takes "world model" far too literally. Audio-visual generative AI models that create non-textual "spaces" are not world models in the sense the previous poster meant. I think what they meant by world model is that the vast majority of the knowledge we rely upon to make decisions is tacit, not something that has been digitized, and not something we even know how to meaningfully digitize and model. And even describing it as tacit knowledge falls short; a substantial part of our world model is rooted in our modes of actions, motivations, etc, and not coupled together in simple recursive input -> output chains. There are dimensions to our reality that, before generative AI, didn't see much systematic introspection. Afterall, we're still mired in endless nature v. nurture debates; we have a very poor understanding about ourselves. In particular, we have extremely poor understanding of how we and our constructed social worlds evolve dynamically, and it's that aspect of our behavior that drives the frontier of exploration and discovery.
OTOH, the "world model" contention feels tautological, so I'm not sure how convincing it can be for people on the other side of the debate.
At no point have I seen anyone here as the question of "What is the minimum viable state of a world model".
We as humans with our ego seem to state that because we are complex, any introspective intelligence must be as complex as us to be as intelligent as us. Which doesn't seem too dissimilar to saying a plane must flap its wings to fly.
I think one could probably argue "yes", to "simple tasks in novel environments". This stuff is super new though.
Note the "Planning" and "Robot Manipulation" parts of V-JEPA 2: https://arxiv.org/pdf/2506.09985:
> Planning: We demonstrate that V-JEPA 2-AC, obtained by post-training V-JEPA 2 with only 62 hours of unlabeled robot manipulation data from the popular Droid dataset, can be deployed in new environments to solve prehensile manipulation tasks using planning with given subgoals. Without training on any additional data from robots in our labs, and without any task-specific training or reward, the model successfully handles prehensile manipulation tasks, such as Grasp and Pick-and-Place with novel objects and in new environments.
That would be like saying studying mathematics can't lead to someone discovering new things in mathematics.
Nothing would ever be "novel" if studying the existing knowledge could not lead to novel solutions.
GPT 5.2 Thinking is solving Erdős Problems that had no prior solution - with a proof.
The point is that the LLM did not model maths to do this, made calls to a formal proof tool that did model maths, and was essentially working as the step function to a search algorithm, iterating until it found the zero in the function.
That's clever use of the LLM as a component in a search algorithm, but the secret sauce here is not the LLM but the middleware that operated both the LLM and the formal proof tool.
That middleware was the search tool that a human used to find the solution.
This is not the same as a synthesis of information from the corpus of text.
It cannot, however, synthesize new facts by combining information from this corpus.
Are we sure? Why can't the LLM use tools, run experiments, and create new facts like humans?The LLM is not the main component in such a system.
But I don't know what you're asking exactly. Maybe you could specify what it is you mean by "real world model" and what you take fact-regurgitating to mean.
But I don't know what you're asking exactly. Maybe you could specify what it is you mean by "real world model" and what you take fact-regurgitating to mean.
You said this: If this existing corpus includes useful information it can regurgitate that.It cannot, however, synthesize new facts by combining information from this corpus.
So I'm wondering if you think world models can synthesize new facts.But that small semantic note aside, if an LLM is used to trigger other tools to find new facts, then those other tools are modeling the "world" or a particular domain. Alternatively you could say that the system as a whole, that the LLM is a part of, models the "world" or a particular domain.
If an LLM uses a calculator to come up with an answer, does it make it worse than a model that can inference the answer without using a tool?
That sounds highly technical if you ask me. People complain if you recompress music or images with lossy codecs, but when an LLM does that suddenly it's religious?
So LLMs are linguistic (token pattern) models of linguistic models (streams of tokens) describing world models (more than tokens).
It thus does not in fact follow that LLMs model the world (as they are missing everything that is not encoded in non-linguistic semantics).
But it is extremely silly to say that "large language models are language models" is a bad faith argument.
Everything you are saying is either incoherent because you actually mean "AI" or "transformer", or is just plain wrong, since e.g. not all problems can be solved using e.g. single-channel, recursively-applied transformers, as I mention elsewhere here: https://news.ycombinator.com/item?id=46948612. The design of LLMs absolutely determines the range of their applicability, and the class of problems they are most suited for. This isn't even a controversial take, lots of influencers and certainly most serious researchers recognize the fundamental limitations of the LLM approach to AI.
You literally have no idea what you are talking about and clearly do not read or understand any actual papers where these models are developed, and are just repeating simplistic metaphors from blog posts, and buying into marketing.