Solving PoP at Scale

Based on these high level building blocks, several requirements can be deduced to evaluate different approaches to a global PoP mechanism:

• Inclusivity and scalability: A global PoP should be maximally inclusive, i.e. available to everyone. This means the mechanism should be able to distinguish between billions of people. There should be a feasible path to implementation at a global scale and people should be able to participate regardless of nationality, race, gender or economic means.

• Fraud Resistant: For a global proof of personhood, the important part is not “identification” (i.e. “is someone who they claim they are?”), but rather negative identification (i.e.“has this person registered before?”). This means that fraud prevention, in terms of preventing duplicate sign-ups, is critical. A significant amount of duplicates would severely restrict the design space of possible applications and make it impossible to treat all humans equally. This would have severe implications for use cases like a fair token distribution, democratic governance, reputation systems like credit scores, and welfare (including UBI).

• Personbound: Once a proof of personhood is issued, it should be personbound: it should be hard to sell or steal (i.e. transfer) and hard to lose. Note that if the PoP mechanism is designed properly, this wouldn’t prevent pseudonymity. This leads to the requirement that the PoP mechanism should allow for authentication in a way that makes it hard for fraudsters to impersonate the legitimate individual. Further, even if the individual lost all information, irrespective of any past actions, it should always be possible for them to recover.

Those cover the requirements that can be deduced from the required building blocks of a proof of personhood mechanism. However, there are further important requirements that can be deduced from the values inherent to the Worldcoin project:

• Decentralization: The issuance of a global PoP credential is foundational infrastructure that should not be controlled by a single entity to maximize resilience and integrity.

• Privacy: The PoP mechanism should preserve the privacy of individuals. Data shared by individuals should be minimized. Users should be in control of their data.