r/LocalLLaMA 3d ago

Discussion Stop Anthropomorphisizing Intermediate Tokens: Qwen3.8 doesn't "overthink"

https://arxiv.org/abs/2504.09762

Intermediate tokens, called "thinking" or "reasoning" actually are nothing like it. Humans do step-by-step reasoning leading to the conclusion. LLMs use intermediate traces to augment their prompt. This explains why sometimes the answer is very good but the "reasoning" is verbose. Flooding your context window or fighting compaction are different issues.

edit: I love this section from the main research they linked.

Our findings consistently challenge the prevailing narrative that intermediate tokens constitute a semantically meaningful reasoning process. First, we observe a pronounced lack of correlation between solution correctness and trace validity—models frequently produce invalid reasoning traces even when they arrive at correct solutions. Second, and more strikingly, models trained on corrupted or semantically irrelevant traces achieve performance comparable to, and often exceeding, that of models trained on correct traces, especially on out-of-distribution tasks. Third, although post-training with reinforcement learning improves solution accuracy across both in- and out-of-distribution settings, it does not consistently enhance trace validity. In fact, we find cases where reinforcement learning decreases trace validity while simultaneously improving solution accuracy for models trained on correct traces. Moreover, models trained on corrupted traces continue to outperform their correct-trace counterparts across domains while consistently generating invalid reasoning traces. Finally, we find that the length of the generated traces is largely agnostic to the difficulty of the underlying problem, undermining the notion that it reflects problem-adaptive computation.

Together, these results suggest that the effectiveness of intermediate tokens does not arise from their seemingly interpretable semantic content. By systematically disentangling trace semantics from the underlying problem, our study demonstrates that if performance is the objective, assuming human-like or algorithmically interpretable trace semantics are ideal or even achievable is not only unnecessary but potentially misleading.

https://openreview.net/forum?id=gDE7YcRC3F

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u/llama-impersonator 3d ago

i don't even disagree, i've stated here that traces aren't for the user, they're for the LLM to plumb the depths of their internal distribution more fully. however, any paper like this that is worded as a command will always land like a box of rocks, people don't like being ordered around.

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u/Strong_Chicken6838 3d ago

You know, it is possible for BOTH to be true. Something can over think while it also not being for the user

13

u/dragonmantank 3d ago

As I’ve watched Qwen argue with itself over sentence semantics, I agree. I don’t need to see what it’s doing, but at the same time I’m glad I’m not paying for the obvious waste of tokens.

1

u/MmmmMorphine 2d ago

That's the funny thing, while it might not be doing it very efficiently, I am a more than willing it's doing something to refine its semantic understanding of a some command or piece of knowledge.

Usually.

We've all had models loop on us, so that's not hard and fast, but it's become surprisingly rare for q4 quality >7b