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LLMs aren't world models

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Re: LLMs aren't world models

#31

I just tried a few things that are simple and a world model would probably get right. Eg Question to GPT5: I am looking straight on to some objects. Looking parallel to the ground. In front of me I have a milk bottle, to the right of that is a Coca-Cola bottle. To the right of that is a glass of water. And to the right of that there’s a cherry. Behind the cherry there’s a cactus and to the left of that there’s a pean…

this seems like a strange riddle. In my mind I was thinking that regardless of the glass, all of the objects can be seen (due to perspective, and also the fact you mentioned the locations, meaning you're aware of them).

It seems to me it would only actually work in an orthographic perspective, which is not how our reality works

Re: LLMs aren't world models

#32
post #14
post #12

As far as I can tell they don’t say which LLM they used which is kind of a shame as there is a huge range of capabilities even in newly released LLMs (e.g. reasoning vs not).

ChatGPT, Claude, Grok and Google AI Overviews, whatever powers the latter, were all used in one or more of these examples, in various configurations. I think they can perform differently, and I often try more than one when the 1st try doesn't work great. I don't think there's any fundamental difference in the principle of their operation, and I think there never will be - there will be another major breakthrough

My hypothesis is that a model fails to switch into a deep thinking mode (if it has it) and blurts whatever it got from all the internet data during autoregressive training. I tested it with alpha-blending example. Gemini 2.5 flash - fails, Gemini 2.5 pro - succeeds.

How presence/absence of a world model, er, blends into all this? I guess "having a consistent world model at all times" is an incorrect description of humans, too. We seem to have it because we have mechanisms to notice errors, correct errors, remember the results, and use the results when similar situations arise, while slowly updating intuitions about the world to incorporate changes.

The current models lack "remember/use/update" parts.

Re: LLMs aren't world models

#33
post #14
post #12

As far as I can tell they don’t say which LLM they used which is kind of a shame as there is a huge range of capabilities even in newly released LLMs (e.g. reasoning vs not).

ChatGPT, Claude, Grok and Google AI Overviews, whatever powers the latter, were all used in one or more of these examples, in various configurations. I think they can perform differently, and I often try more than one when the 1st try doesn't work great. I don't think there's any fundamental difference in the principle of their operation, and I think there never will be - there will be another major breakthrough

Each of these models has a thinking/reasoning variant and a default non-thinking variant. I would expect the reasoning variants (o3 or “GPT5 Thinking”, Gemini DeepThink, Claude with Extended Thinking, etc) to do better at this. I think there is also some chance that in their reasoning traces they may display something you might see as closer to world modelling. In particular, you might find them explicitly tracking positions of pieces and checking validity.

Re: LLMs aren't world models

#34
A slight tangent: I think/wonder if the one place where AIs could be really useful, might be in translating alien languages :)

As in, an alien could teach one of our AIs their language faster than an alien could teach an human, and vice versa..

..though the potential for catastrophic disasters is also great there lol

Re: LLMs aren't world models

#35

This essay could probably benefit from some engagement with the literature on “interpretability” in LLMs, including the empirical results about how knowledge (like addition) is represented inside the neural network. To be blunt, I’m not sure being smart and reasoning from first principles after asking the LLM a lot of questions and cherry picking what it gets wrong gets to any novel insights at this point. And it alr…

https://arxiv.org/abs/2508.01191

Re: LLMs aren't world models

#36
post #14
post #12

As far as I can tell they don’t say which LLM they used which is kind of a shame as there is a huge range of capabilities even in newly released LLMs (e.g. reasoning vs not).

ChatGPT, Claude, Grok and Google AI Overviews, whatever powers the latter, were all used in one or more of these examples, in various configurations. I think they can perform differently, and I often try more than one when the 1st try doesn't work great. I don't think there's any fundamental difference in the principle of their operation, and I think there never will be - there will be another major breakthrough

> I don't think there's any fundamental difference in the principle of their operation

Yeah, they seem to be a subject to the universal approximation theorem (it needs to be checked more thoroughly, but I think we can build a transformer that is equivalent to any given fully-connected multilayered network).

That is at a certain size they can do anything a human can do at a certain point in their life (that is with no additional training) regardless of whether humans have world models and what those model are on the neuronal level.

But there are additional nuances that are related to their architectures and training regimes. And practical questions of the required size.

Re: LLMs aren't world models

#37
post #8

This essay could probably benefit from some engagement with the literature on “interpretability” in LLMs, including the empirical results about how knowledge (like addition) is represented inside the neural network. To be blunt, I’m not sure being smart and reasoning from first principles after asking the LLM a lot of questions and cherry picking what it gets wrong gets to any novel insights at this point. And it alr…

With LLMs being unable to count how many Bs are in blueberry, they clearly don't have any world model whatsoever. That addition (something which only takes a few gates in digital logic) happens to be overfit into a few nodes on multi-billion node networks is hardly a surprise to anyone except the most religious of AI believers.

The core issue there isn't that the LLM isn't building internal models to represent its world, it's that its world is limited to tokens. Anything not represented in tokens, or token relationships, can't be modeled by the LLM, by definition.

It's like asking a blind person to count the number of colors on a car. They can give it a go and assume glass, tires, and metal are different colors as there is likely a correlation they can draw from feeling them or discussing them. That's the best they can do though as they can't actually perceive color.

In this case, the LLM can't see letters, so asking it to count them causes it to try and draw from some proxy of that information. If it doesn't have an accurate one, then bam, strawberry has two r's.

I think a good example of LLMs building models internally is this: https://rohinmanvi.github.io/GeoLLM/

LLMs are able to encode geospatial relationships because they can be represented by token relationships well. Teo countries that are close together will be talked about together much more often than two countries far from each other.

Re: LLMs aren't world models

#38
post #8

This essay could probably benefit from some engagement with the literature on “interpretability” in LLMs, including the empirical results about how knowledge (like addition) is represented inside the neural network. To be blunt, I’m not sure being smart and reasoning from first principles after asking the LLM a lot of questions and cherry picking what it gets wrong gets to any novel insights at this point. And it alr…

With LLMs being unable to count how many Bs are in blueberry, they clearly don't have any world model whatsoever. That addition (something which only takes a few gates in digital logic) happens to be overfit into a few nodes on multi-billion node networks is hardly a surprise to anyone except the most religious of AI believers.

> they clearly don't have any world model whatsoever

Then how did an LLM get gold on the mathematical Olympiad, where it certainly hadn’t seen the questions before? How on earth is that possible without a decent working model of mathematics? Sure, LLMs might make weird errors sometimes (nobody is denying that), but clearly the story is rather more complicated than you suggest.

Re: LLMs aren't world models

#39
That whole bit about color blending and transparency and LLMs "not knowing colors" is hard to believe. I am literally using LLMs every day to write image-processing and computer vision code using OpenCV. It seamlessly reasons across a range of concepts like color spaces, resolution, compression artifacts, filtering, segmentation and human perception. I mean, removing the alpha from a PNG image was a preprocessing step it wrote by itself as part of a larger task I had given it, so it certainly understands transparency.

I even often describe the results e.g. "this fails when in X manner when the image has grainy regions" and it figures out what is going on, and adapts the code accordingly. (It works with uploading actual images too, but those consume a lot of tokens!)

And all this in a rather niche domain that seems relatively less explored. The images I'm working with are rather small and low-resolution, which most literature does not seem to contemplate much. It uses standard techniques well known in the art, but it adapts and combines them well to suit my particular requirements. So they seem to handle "novel" pretty well too.

If it can reason about images and vision and write working code for niche problems I throw at it, whether it "knows" colors in the human sense is a purely philosophical question.

Re: LLMs aren't world models

#40

This essay could probably benefit from some engagement with the literature on “interpretability” in LLMs, including the empirical results about how knowledge (like addition) is represented inside the neural network. To be blunt, I’m not sure being smart and reasoning from first principles after asking the LLM a lot of questions and cherry picking what it gets wrong gets to any novel insights at this point. And it alr…

Any suggestions from this literature?

The papers from Anthropic on interpretability are pretty good. They look at how certain concepts are encoded within the LLM.
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