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Why I'm still bearish on LLMs after Navier-Stokes

496 points · 653 comments · jaykru

  1. carodgers · · focus · HN ↗
    This April 2026 paper is a fun and related read.

    <a href="https:&#x2F;&#x2F;arxiv.org&#x2F;html&#x2F;2509.24239v4" rel="nofollow">https:&#x2F;&#x2F;arxiv.org&#x2F;html&#x2F;2509.24239v4

    Researchers asked frontier models to play chess. Have a look at the MAR rates in Table 3. When not explicitly told which moves were legal, no model identified legal moves at a rate better than 80%. Many asked for more illegal moves than legal moves. And even when explicitly told which moves were legal, the models continued to ask for illegal moves. With illegal asks discarded, none of the bots could beat a chess model calibrated to 1100 ELO.

    The author of the originating post says that &quot;current frontier models need laborious oversight and guardrails on even the simplest tasks&quot;, and he&#x27;s absolutely correct.

    1. glitchc · · focus · HN ↗
      Why not ask it to implement a chess engine first, and then use that to play against you?

      Does the LLM need to learn to play chess if it can build a chess engine to play for it instead?

      1. lionkor · · focus · HN ↗
        With that approach, the benchmark falls apart. Of course it can write a chess engine, because it learned on lots of stolen source code of chess engines. This has nothing to do with the LLM&#x27;s ability to reason.

        Writing a well understood engine for a super popular problem does not count as reasoning about the problem.

        1. glitchc · · focus · HN ↗
          &gt; Writing a well understood engine for a super popular problem does not count as reasoning about the problem.

          Doesn&#x27;t writing the engine imply understanding about the problem domain? Tool use is a widely accepted measure of intelligence.

          1. well_ackshually · · focus · HN ↗
            &gt;Tool use is a widely accepted measure of intelligence.

            Stop anthropomorphizing the parrot. The parrot has had stockfish&#x27;s source code blasted at high pressure into its head along with dozens of millions of other pieces of code whose sole role is to have efficient algorithms to more or less brute force through the best result. Brute forcing (no matter how smart it is) isn&#x27;t understanding the problem domain.

            1. glitchc · · focus · HN ↗
              I&#x27;m not fully convinced that human beings aren&#x27;t stochastic parrots. Much of the behaviour I observe in daily life reflects a blind adherence to set of beliefs that are an amalgation of &quot;a person of authority said to do this&quot; at an early age.
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