Exchanges with and without the sword: slavery, politics-as-exchange and freedom in James M. Buchanan's institutional economics
批判布坎南的“作为交换的政治”概念，指出其将奴隶制视为双边协议，逻辑上要求奴隶主同意才能废除，并建议引入退出权以区分强制与自愿交换，从而构建一致的自由主义宪政。
Abstract James M. Buchanan's politics-as-exchange retrospectively conceptualized formal institutions emerging from bilateral agreements to establish reciprocal rights and prospectively guided constitutional entrepreneurs to broker Pareto-superior reforms that had unanimous consent. Buchanan believed this conceptualization of politics-as-exchange was necessitated by his ontological–methodological individualism and would initiate a new era of consensual politics, but it is argued it led to illiberal conclusions that reflected dissonance between his Kantian individualism and Humean subjectivism. It meant, for example, that slavery was characterized as a bilateral agreement between very unequal parties and it is argued it logically implied abolition required the consent of slaveowners. But Buchanan's ontology was compatible with the introduction into his framework of a right of exit that would have differentiated between exchanges with and without the sword to produce a consistent liberal constitutionalism.