Beyond ‘permissionless’: governance, commitment, and rule change in public blockchains
批评区块链经济学中‘无需许可’的假设，指出其忽略了规则变更的治理问题。通过分析八个公共区块链系统及两个案例，论证区块链安全受制于制度承诺条件，如基础层固定性、联盟集中度等。
Abstract The blockchain economics literature often models consensus participants as anonymous, interchangeable agents operating without institutional context. This paper argues that this ‘permissionless’ assumption describes open admission but abstracts from governance over rule change. Once governance is restored, mutable blockchain systems face a standard commitment problem: rule-changing coalitions may revise protocol rules after participants make chain-specific investments. The paper develops this claim through a comparative-institutional analysis of eight public blockchain systems and two illustrative cases: the BTC Core governance episode and the Ethereum DAO intervention. TCP/IP provides the institutional comparator: technical systems can evolve extensively while preserving base-layer semantic fixedness. Once governance is included, blockchain security is constrained not only by consensus costs but also by institutional commitment conditions: base-layer fixedness, coalition concentration, coordination thresholds, and identity-linked accountability.