Buterin Warns Sam Altman’s World Threatens Online Privacy
Ethereum co-founder Vitalik Buterin warned on June 28, 2025, that the eyeball-scanning digital identification system promoted by Sam Altman’s World project poses critical privacy risks by threatening user pseudonymity.
Formerly operating as Worldcoin, the rebranded “World” initiative was launched by Tools for Humanity, an organization co-founded by Sam Altman and Alex Blania. The project’s core mission is to differentiate human users from artificial intelligence agents by capturing biometric eyeball scans and registering a unique, verified identity on the blockchain.
In a comprehensive blog post, Buterin highlighted that World’s method—utilizing zero-knowledge proofs (ZKPs) to authenticate humanity while preserving anonymity—mirrors strategies currently investigated by several digital ID and passport initiatives. The Ethereum creator conceded that, superficially, a “ZK-wrapped digital ID” seems promising for safeguarding social media, voting systems, and online services from bot manipulation without sacrificing user privacy.
The Hidden Dangers of a “One-Per-Person” ID System
Despite these apparent benefits, Buterin cautioned that the underlying “one-per-person” framework introduces severe structural dangers. He explained that real-world privacy and pseudonymity rely heavily on maintaining separate accounts for different activities. Under a singular ID system, even one shielded by zero-knowledge proofs, society risks drifting toward a reality where all online actions are tied back to a single public persona. Buterin warned that stripping away the ability to remain pseudonymous carries dangerous consequences in an increasingly volatile world.
Real-World Surveillance and Government Coercion
To illustrate these dangers, Buterin pointed to recent policy shifts, such as the U.S. government requiring student and scholar visa applicants to make their social media accounts public for hostility screening. He argued that even if no obvious connection exists between accounts linked to a single digital ID, state actors could easily compel individuals to unlock their private keys, exposing their entire digital footprint.
The Alternative: Embracing Pluralistic Identity
To solve the bot-verification dilemma without compromising personal privacy, Buterin champions a decentralized concept known as “pluralistic identity.” This model rejects any single dominant authority—be it an individual, corporation, or platform—for issuing credentials.
Instead, pluralistic verification can function explicitly, using peer-to-peer trust networks, or implicitly, by combining multiple independent identity verification systems. Buterin views this hybrid, decentralized approach as the most viable path forward.
He suggested that the most constructive path forward for current “one-per-person” biometric initiatives would be to integrate their technologies with decentralized, social-graph-based identity networks.
