{"slug": "claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight", "title": "Claude Fable 5.1 decoded a centuries-old royalist message hidden in plain sight since 1653", "summary": "Anthropic's Claude Fable 5.1 decoded a 371-year-old royalist cipher, the 'Cyphral Distich' by Sir Thomas Urquhart, in 44 minutes without human help, according to Vals AI. The solution, which spells 'O God uphold King Charls the Second and make him the supreme ruler of this land,' was found by systematically mapping each number to words in Urquhart's 1653 publication. Vals AI noted that Fable 5.1 succeeded through persistence rather than superior cryptanalysis.", "body_md": "# Claude Fable 5.1 decoded a centuries-old royalist message hidden in plain sight since 1653\n\n**Anthropic's Claude Fable 5.1 appears to have cracked a centuries-old number puzzle that researchers considered unsolved.** The \"Cyphral Distich\" by Sir Thomas Urquhart, published in 1653, consists of two lines of 32 numbers each. [According to Vals AI](https://www.vals.ai/blogs/fable-solves-cyphral-distich), Fable 5.1 solved it in 44 minutes with no human help.\n\nThe author had spent months testing other frontier models on unsolved puzzles. None produced a verifiable solution. Fable 5.1 was tasked with finding a solvable puzzle on its own. It sifted through various problems and flagged the Cyphral Distich as promising.\n\nThe key was hiding in the book itself. Each number points to a word in one of the 32 sections of Urquhart's publication. The first letters of those words spell out: \"O God uphold King Charls the Second and make him the supreme ruler of this land.\" In hindsight, the solution is simple, and humans could have solved it too. [Fable 5.1 succeeded](https://the-decoder.com/anthropics-claude-fable-5-1-promises-better-coding-and-research-at-up-to-45-percent-less/) not through better cryptanalysis but through systematic trial and error and sheer persistence, according to Vals AI.\n\n```\nAI News Without the Hype – Curated by Humans\n\n\t\t\t\t\tSubscribe to THE DECODER for ad-free reading, a weekly AI newsletter, our exclusive \"AI Radar\" frontier report six times a year, full archive access, and access to our comment section.\t\t\t\t\n\n\t\t\t\t\tSubscribe now\n```\n\n[Vals AI / Cyphral Distich](https://www.vals.ai/blogs/fable-solves-cyphral-distich)", "url": "https://wpnews.pro/news/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight", "canonical_source": "https://the-decoder.com/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight-since-1653/", "published_at": "2026-09-03 14:15:28+00:00", "updated_at": "2026-09-03 14:26:19.295732+00:00", "lang": "en", "topics": ["artificial-intelligence", "large-language-models", "ai-research"], "entities": ["Anthropic", "Claude Fable 5.1", "Vals AI", "Sir Thomas Urquhart", "Cyphral Distich"], "alternates": {"html": "https://wpnews.pro/news/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight", "markdown": "https://wpnews.pro/news/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight.md", "text": "https://wpnews.pro/news/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight.txt", "jsonld": "https://wpnews.pro/news/claude-fable-5-1-decoded-a-centuries-old-royalist-message-hidden-in-plain-sight.jsonld"}}