The God Protocols

Nick Szabo's essay "The God Protocols" argues that multiparty secure computation can, in principle, replace trusted third parties in contracts, including negotiations, with a virtual computer that needs no trusted intermediary. He describes a "blind bargaining" example in which Alice submits a bid, Bob submits an ask, and the shared program returns only whether the bid exceeds the ask. Szabo identifies three practical limits: the virtual computer is very slow, privacy, fairness and fault tolerance trade off against one another, and it can only do what its algorithm and inputs specify. He also suggests that mutually confidential auditing could support reputation systems, though he notes that performance-phase enforcement is less developed.