A small group of causally-implicated hidden states encodes LLM truth representations, localized over clause-ending punctuation tokens

Entities in the same semantic neighborhood but without a typed relation to this one — candidates for new edges or unrecognized duplicates.

• We hypothesize that group (b) hidden states store a representation of the statement's truthhypothesis0.812
  Motivating hypothesis driving the remainder of the paper's analysis after patching localization
• Patching group (b) hidden states (over clause-ending punctuation, early-middle layers) in LLaMA-2-13B produces the strongest causal effect on TRUE/FALSE output predictionsfinding0.808
  Localizes truth representations to specific hidden states, motivating the rest of the analysis
• Little evidence of steganography in NLAs; meaning-preserving transformations cause only small drops in FVEfinding0.778
  Quantitative evaluation showing NLAs do not heavily rely on covert encoding beyond overt language.
• LLMs linearly represent truth-relevant information beyond the plausibility of text, as evidenced by probes trained on likely performing poorly on anti-correlated datasetsclaim0.774
  Establishes that the observed linear structure is not merely a representation of text probability
• Do LLMs have a unified representation of truth that spans structurally and topically diverse data?question0.768
  Central research question driving dataset design and experimental approach
• Linear truth directions in LLMs are reliable primarily in factual recall cases and break down when truth assessment depends on computing and storing intermediate results.claim0.768
  Central empirical conclusion of the paper about the fundamental limits of truth directions.
• Internal states appear to encode Bayesian beliefs about hidden external states.claim0.765
  The inferential interpretation of internal dynamics.
• Are LLM emotion states encoded only selectively in token positions where they are operative, or in a more complex non-linear manner?question0.763
  Question raised by Anthropic and partially addressed by this paper's persistence evidence