Fable 5.2 is Scary Powerful

Anthropic just released Fable 5.2. To show what it can do, they put a thousand copies of it on one of the hardest proofs in math and didn't tell them how to work together. In ten minutes the AIs had organized themselves like a company. In under thirty hours they finished a job that took eleven days two months earlier. So how big of a jump is this model? This video goes through that run using the messages the AIs wrote to each other, what else the model built, and the one skill Anthropic says it held back on purpose: the research that builds better AI. 0:00 Why Fable 5.2 matters 1:10 Fermat's Last Theorem 2:55 1,000 AIs, no boss 4:24 "Honest odds are low" 5:53 What else it built 6:50 The skill Anthropic held back 8:23 My take ## Sources - Anthropic, "Introducing Claude Fable 5.2 and Claude Mythos 5.2" (Nov 9, 2026) - Anthropic, Claude Fable 5.2 and Mythos 5.2 system card - Anthropic, "Safely scaling multi-agent teams with Claude Fable 5.2" - Anthropic, "Formalizing Fermat's Last Theorem" (Sep 4, 2026) - Anthropic, "Claude-designed electronics" - Anthropic, "Redeploying Fable 5" (July 2026) - METR, "Independent Assessment of AI R&D Acceleration at Anthropic in October 2026" - Kevin Buzzard, Mathematical Foundations of AI Conference 2026 (Erlangen AI Hub) - The Next Web, Fortune Social X - https://x.com/davelee Apple Podcast: https://podcasts.apple.com/us/podcast/dave-lee-on-investing/id1493031991 Spotify https://open.spotify.com/show/2iin015s0k21Bt4ldep9XT?si=uBV4Ft8hQEu_GE4YSIDDGg Instagram https://www.instagram.com/heydave7 Dave Lee on Parenting, https://www.youtube.com/channel/UCWD9b1BZqi2G2u30sGYIFrA NOTE: Please don’t fall for scammers who might impersonate me or others in the comment section. I do NOT give out my number or ask people to contact me. 💁🏻‍♂️ Disclaimer: All content on this channel is for discussion and illustrative purposes only and should not be construed as professional financial advice or recommendation to buy or sell any securities. Should you need such advice, consult a licensed financial or tax advisor. All views expressed are personal opinion as of date of recording and are subject to change without responsibility to update views. No guarantee is given regarding the accuracy of information on this channel. Neither host or guests can be held responsible for any direct or incidental loss incurred by applying any of the information offered. Author is long TSLA and other stocks at time of original video publish date.

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