Confident and wrong
A model that stores knowledge in distributed weights has no way to flag its own uncertainty.
A database can tell you "this record doesn't exist." A language model can't check whether a fact is in its weights before generating it — it just generates what's most probable. And what's most probable often sounds correct, because the training data contained mostly correct information.
This produces a specific failure mode: hallucination. The model generates text that sounds authoritative and is completely false. It might invent citations to papers that don't exist. It might describe a historical event that never happened, in accurate-sounding detail. It might give a confident answer about a law that doesn't say what the model claims.
The model isn't lying. It has no concept of truth versus falsehood. It's predicting what would plausibly follow from the prompt — and sometimes what would plausibly follow is wrong.
This is structural. It's not a bug that will be fixed in the next version. Understanding it changes how you should use these tools.
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