Vitalik Buterin warns Sam Altman’s World digital IDs risk killing pseudonymity online

Ethereum co-founder Vitalik Buterin has some concerns related to digital identity projects like World, which claims to have signed up more than 13 million “unique humans.”

In a post published Saturday, Buterin chose to specifically discuss the risks and rewards of digital ID projects which utilize zero-knowledge proofs. While the popular thought leader had much to say on the matter, one of his major assertions is that projects like World (formerly Worldcoin), which is famously backed by OpenAI CEO Sam Altman, could kill off the pseudonymity that so many internet users enjoy, especially in the crypto space.

“Under one-per-person ID, even if ZK-wrapped, we risk coming closer to a world where all of your activity must de-facto be under a single public identity,” Buterin wrote in his post. “In a world of growing risk (eg. drones), taking away the option for people to protect themselves through pseudonymity has significant downsides.”

World is a digital identity project primarily developed and promoted by Tools for Humanity, which was co-founded by Altman and CEO Alex Blania. Users who have their eyeball scanned to prove they are human are given both a World ID and a crypto bonus in the form of WLD tokens. The biometric data collected by World’s silvery Orbs to create a digital identity is protected, in part, by using zero-knowledge proofs, a solution also called ZK wrapping, which allows a user to prove something is true (like being a human) without revealing the underlying data (their actual identity).

Buterin acknowledges in his post that digital identity initiatives which use zero-knowledge proofs appear to be going mainstream, mentioning not only World, but also both European Union and Taiwanese initiatives.

While Buterin sees downsides to any one-ID-for-each-person system, he admitted there are benefits, such as helping to discern from AI-powered agents. One of World’s biggest selling points is the notion that it can make the internet a better place by helping users know which other users are human and which are not.

“On the surface, widespread adoption of ZK-wrapped digital ID seems like it would be a great victory … protecting our social media, voting, and all kinds of internet services against manipulation from sybils and bots, all without compromising on privacy,” he wrote. 

But to take advantage of pseudonymity, one needs to be able to do things like possess and manage multiple email and social media accounts. ZK-wrapped, digital identity projects like World, could put pseudonymity in jeopardy if implemented rigidly, argues Buterin.

“In this world, social media apps … will just use one app-specific ID for each user, and because the ID system is one-per-person, each user will only be able to have one account (as opposed to “weak ID” like eg. Google accounts today, where it’s reasonably feasible for an average person to get ~5 accounts),” Buterin added.

World, which for months after launching triggered criticism among privacy advocates across the globe, has gained momentum lately. The project recently launched in the United States and plans a Visa card. It also has a pilot program lined up with Tinder in Japan that would provide users with greater clarity about the identities of those they are interacting with on the dating app.

Instead of a single ZK-wrapped “one-per-person ID” solution, Buterin suggests using a pluralistic model where no one person, institution or platform is in charge of issuing digital identities.

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