(Audio version, read by the author, here, or search for "Joe Carlsmith Audio" on your podcast app.)

Last Friday was my last day at Open Philanthropy. I’ll be starting a new role at Anthropic in mid-November, helping with the design of Claude's character/constitution/spec. This post reflects on my time at Open Philanthropy, and it goes into more detail about my perspective and intentions with respect to Anthropic – including some of my takes on AI-safety-focused people working at frontier AI companies.

(I shared this post with Open Phil and Anthropic comms before publishing, but I’m speaking only for myself and not for Open Phil or Anthropic.)

On my time at Open Philanthropy

I joined Open Philanthropy full-time at the beginning of 2019.[1] At the time, the organization was starting to spin up a new “Worldview Investigations” team, aimed at investigating and documenting key beliefs driving the organization's cause prioritization – and with a special focus on how the organization should think about the potential impact at stake in work on transformatively powerful AI systems.[2] I joined (and eventually: led) the team devoted to this effort, and it's been an amazing project to be a part of.

I remember [...]

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Outline:

(00:51) On my time at Open Philanthropy

(08:11) On going to Anthropic

The original text contained 25 footnotes which were omitted from this narration.

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First published:
November 3rd, 2025

Source:
https://www.lesswrong.com/posts/3ucdmfGKMGPcibmF6/leaving-open-philanthropy-going-to-anthropic

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Narrated by TYPE III AUDIO.

“Leaving Open Philanthropy, going to Anthropic” by Joe Carlsmith

LessWrong (30+ Karma)