A sufficiently large random reversible circuit is plausibly a secure cryptographic permutation, while a large random irreversible circuit collapses to only a few possible outputs.

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1. 21 Aug 2026

   Vitalik Buterin quoted

   Their wordsA big-enough random reversible circuit is plausibly a secure cryptographic permutation, a big-enough random irreversible circuit degenerates into having only a few possible outputs.

   ↗Obfuscation (Part III): Local Mixingvitalik.eth.limo