The Most Forbidden Technique is training an AI using interpretability techniques.

An AI produces a final output [X] via some method [M]. You can analyze [M] using technique [T], to learn what the AI is up to. You could train on that. Never do that.

You train on [X]. Only [X]. Never [M], never [T].

Why? Because [T] is how you figure out when the model is misbehaving.

If you train on [T], you are training the AI to obfuscate its thinking, and defeat [T]. You will rapidly lose your ability to know what is going on, in exactly the ways you most need to know what is going on.

Those bits of optimization pressure from [T] are precious. Use them wisely.

Table of Contents

1. New Paper Warns Against the Most Forbidden Technique.
2. Reward Hacking Is The Default.
3. Using [...]

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Outline:

(00:57) New Paper Warns Against the Most Forbidden Technique

(06:52) Reward Hacking Is The Default

(09:25) Using CoT to Detect Reward Hacking Is Most Forbidden Technique

(11:49) Not Using the Most Forbidden Technique Is Harder Than It Looks

(14:10) It's You, It's Also the Incentives

(17:41) The Most Forbidden Technique Quickly Backfires

(18:58) Focus Only On What Matters

(19:33) Is There a Better Way?

(21:34) What Might We Do Next?

The original text contained 6 images which were described by AI.

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First published:
March 12th, 2025

Source:
https://www.lesswrong.com/posts/mpmsK8KKysgSKDm2T/the-most-forbidden-technique

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Narrated by TYPE III AUDIO.

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