斯坎伦的契约主义道德理论,是为了取代效益主义而建立起来的。效益主义在证成一个行为的道德正确性时,会考虑受该行为影响的人的福祉总计,因而人数很多时变得很重要。人数在道德上的重要性,似乎也符合我们的直觉。这也是效益主义有吸引力的其中一个理由。斯坎伦的契约主义,由于坚持只有个人理由才构成反对一项原则的理据,因而面临难以说明人数在道德上重要的问题。他提出“打破平衡论证”来尝试说明,在不依赖总计的情况下,也能说明人数的重要。本文认为他的论证是不成功的,但只要引入几个重要区分,在契约主义框架内,其实可以容纳总计而不会滑向效益主义。 Scanlan’s contractarian moral theory was established to replace the benefit doctrine. Benefit doctrine, in justifying the moral correctness of an act, takes into account the total well-being of those affected by the act, and becomes significant when the number is large. The moral importance of numbers seems to fit our intuition. It is also one of the reasons why benefit doctrine is attractive. Scanlon’s contractarianism, faced with a mere personal justification that justifies its opposition to a principle, faces a problem that makes it difficult to account for the ethical importance of numbers. He proposed “breaking the balance argument ” to try to explain that, independent of the total, it can also explain the importance of the number. This article argues that his argument is unsuccessful, but as long as a few important distinctions are introduced, it is in the framework of contractualism that it can accommodate aggregates without slips into benefits.