person1981–

Holden Karnofsky

Disciplines:

Summary

American philanthropist — co-founder of GiveWell (charity effectiveness evaluation) and Open Philanthropy — who has directed over $1B in philanthropic giving toward effective causes — and who has become increasingly focused on AI safety as a priority.

Core Contribution

Creates GiveWell as evidence-based charity evaluation — Karnofsky's GiveWell introduced systematic effectiveness evaluation of charities (cost per life saved, rigorous evidence standards) that transformed how institutional philanthropy thinks about giving, and his Open Philanthropy project extended this approach to existential risk and AI safety.

Key Spikes & Highlights

Left Bridgewater to start GiveWell after being unable to find good evidence for which charities actually saved the most lives — his frustration with the non-transparency of the charity industry produced the most rigorous charity evaluation organization ever created; he found as a 25-year-old that no existing charity evaluator actually looked at evidence
Has publicly updated toward AI safety being the most important near-term philanthropic cause — his move from global health to AI safety represents the EA movement's largest public pivot and influenced hundreds of millions of dollars of philanthropic allocation

Notable Works & Achievements

GiveWell research reports

Cold Takes Substack

Open Philanthropy grant writeups

Historical Influences

Peter Singer Effective altruism movement

Intellectual Lineage

Harvard Bridgewater Associates GiveWell Open Philanthropy

Contemporaries & Peers

Elie Hassenfeld Dustin Moskovitz Will MacAskill

Minds Influenced

Philanthropy methodology EA movement

Intellectual Posterity

GiveWell Open Philanthropy Evidence-based philanthropy

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