Hallucination Is Inevitable: An Innate Limitation of Large Language Models

drob518 12 points 11 comments May 04, 2026
arxiv.org · View on Hacker News

Discussion Highlights (6 comments)

bell-cot

IANAL, nor expert in this space. But might any such care to comment on the consequences, if this "it is impossible, even in theory , to eliminate LLM hallucinations" result holds up?

Jiro

From that abstract it doesn't sound like they allowed for the possibility that the LLM could be trained to say "I don't know" for some things.

thomastjeffery

Describing it as a limitation is the problem. Hallucination is the core feature. It's the only thing they do!

whythismatters

>Submitted on 22 Jan 2024 (v1), last revised 13 Feb 2025 (this version, v2)

stevefan1999

LLM or transformers just merely extracting signals from human text and build a "contextualized" predictor over a long sequence of words sorted by the information (technically it is attention) of each token, then generate sentences that way, one by one into other sequences at a time. But the biggest problem is, even human itself is subjectable to hallucination. That is called being delusional, or being drugged. So it is inevitable from the first principle.

red75prime

They prove that no finite amount of training data is enough to extrapolate an adversarially constructed non-continuous function. It's something akin to the no free lunch theorem (NFL). No one uses the NFL to "prove" that LLMs can't learn to be the best optimizers, because it also proves that people can't be the best optimizers, but we manage somehow, so the theorem is irrelevant. This is a fallacy of proving too much.

Semantic search powered by Rivestack pgvector
8,303 stories · 78,303 chunks indexed