Act and principle contractualism

Unrejectability is the property shared by things no one could reasonably reject. Following the lead of T. M. Scanlon, modern contractualists hold Principle Contractualism: An act is obligatory when conformity to unrejectable principles requires its performance. This article entertains Act Contractualism: An act is obligatory when its performance is unrejectable. The article hypothesizes that Principle Contractualism owes its initial plausibility to the assumption that following it somehow realizes unrejectability, if only indirectly. The article then argues that, whereas following Act Contractualism realizes unrejectability, following Principle Contractualism realizes a convoluted, principle-mediated, non-causal conformity relation between acts and unrejectability. But then the notion that this relation is what matters ultimately in action does not seem to enjoy independent plausibility. After interrogating Scanlon's objection that the challenge to the principle-based nature of contractualism is 'misconceived', I conclude that Act Contractualism is the more fitting contractualist theory of obligation.