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naaskingyesterday at 7:50 PM3 repliesview on HN

I think it's correct to say that LLM have word models, and given words are correlated with the world, they also have degenerate world models, just with lots of inconsistencies and holes. Tokenization issues aside, LLMs will likely also have some limitations due to this. Multimodality should address many of these holes.


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swyxyesterday at 9:27 PM

(editor here) yes, a central nuance i try to communicate is not that LLMs cannot have world models (and in fact they've improved a lot) - it is just that they are doing this so inefficiently as to be impractical for scaling - we'd have to scale them up to so many more trillions of parameters more whereas our human brains are capable of very good multiplayer adversarial world models on 20W of power and 100T neurons.

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AreShoesFeet000yesterday at 8:07 PM

So you think that enough of the complexity of the universe we live in is faithfully represented in the products of language and culture?

People won’t even admit their sexual desires to themselves and yet they keep shaping the world. Can ChatGPT access that information somehow?

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D-Machineyesterday at 8:03 PM

It's also important to handle cases where the word patterns (or token patterns, rather) have a negative correlation with the patterns in reality. There are some domains where the majority of content on the internet is actually just wrong, or where different approaches lead to contradictory conclusions.

E.g. syllogistic arguments based on linguistic semantics can lead you deeply astray if you those arguments don't properly measure and quantify at each step.

I ran into this in a somewhat trivial case recently, trying to get ChatGPT to tell me if washing mushrooms ever really actually matters practically in cooking (anyone who cooks and has tested knows, in fact, a quick wash has basically no impact ever for any conceivable cooking method, except if you wash e.g. after cutting and are immediately serving them raw).

Until I forced it to cite respectable sources, it just repeated the usual (false) advice about not washing (i.e. most of the training data is wrong and repeats a myth), and it even gave absolute nonsense arguments about water percentages and thermal energy required for evaporating even small amounts of surface water as pushback (i.e. using theory that just isn't relevant when you actually properly quantify). It also made up stuff about surface moisture interfering with breading (when all competent breading has a dredging step that actually won't work if the surface is bone dry anyway...), and only after a lot of prompts and demands to only make claims supported by reputable sources, did it finally find McGee's and Kenji Lopez's actual empirical tests showing that it just doesn't matter practically.

So because the training data is utterly polluted for cooking, and since it has no ACTUAL understanding or model of how things in cooking actually work, and since physics and chemistry are actually not very useful when it comes to the messy reality of cooking, LLMs really fail quite horribly at producing useful info for cooking.