Why language models hallucinate

I find this rather oddly phrased.

LLMs hallucinate because they are language models. They are stochastic models of language. They model language, not truth.

If the “truthy” responses are common in their training set for a given prompt, you might be more likely to get something useful as output. Feels like we fell into that idea and said - ok this is useful as an information retrieval tool. And now we use RL to reinforce that useful behaviour. But still, it’s a (biased) language model.

I don’t think that’s how humans work. There’s more to it. We need a model of language, but it’s not sufficient to explain our mental mechanisms. We have other ways of thinking than generating language fragments.

Trying to eliminate cases where a stochastic model the size of an LLM gives “undesirable” or “untrue” responses seems rather odd.

The reality is, language itself does not capture the entirety of what is really going on. And I'd get argue its the poorest way of expressing - but one that enables transmission through various mediums efficiently on a cost basis.

E.g. when I explain a concept, what comes to my mind is not a string of letters and words. There is a mix of imagery and even sounds that I may have acquired from learning about a concept - then I translate that into text so it can be communicated.

Theres a reason why people use native subtitles when watching netflix - text complements imagery and sounds.

I would assume most people use native subtitles when it's hard to understand what words the actors said.