Vitalik Buterin explains that pluralistic identity systems can function either explicitly through social verification (e.g., Circles) or implicitly through multiple existing ID sources, thereby avoiding identity monopolies.

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He explained these could be explicit, using social-graph-based verification like Circles, or implicit, relying on multiple ID providers — government documents, social platforms, and others — so no one ID gains near-total market share.

Explicit pluralistic identity or ‘social-graph-based identity,’ a user has to prove a certain feature through attestations from others in the community Implicit pluralistic identity system, a user can provide any ID—government IDs or social media IDs—for verification.