welfare. The bargainers’ personhood-respecting motive then adds further content to these restrictions by insisting that they be genuine deontological constraints. This distinction between ‘restrictions’ and ‘constraints’ is most fully illustrated by considering the different ways in which they are defeasible: restrictions can be overridden for the sake of the greater good (for they were erected in the first place solely for the purpose of serving the greater overall good), while constraints cannot. The defeasibility of restrictions is compatible with the action required in ‘Transplant’; the defeasibility of constraints is not.
These constraints express more than just the bargainers’ desire to maximize overall well-being – they give voice to the bargainers’ desire that their moral system give adequate expression to their moral status as persons. The erection of constraints respects the sanctity of each person, as they protect persons from infringement not only insofar as this protection leads to the greater overall good, but even in those cases where infringing persons actually would be optimific.
Still, though, these constraints admit of principled exceptions. In fact, special features of the social-contract scenario seem to require the adoption of some sort of ‘defeasibility clause.’ Such a clause generates the exceptions necessary to prevent the social contract, once implemented, from collapsing back onto itself, as it were, by enabling free-riders to exploit the system to their own advantage. The bargainers’ first motive leads to the formulation of just such a principle, which justifies exceptions anytime adherence to the restrictions would be directly contrary to the initial self-interest- maximizing motive that led to the adoption of the restrictions in the first place. Once again, though, the bargainers’ second motive steps in to modify this defeasibility principle, requiring that only exceptions that are compatible with the moral status of persons may be permitted. (This is just to say that only the exceptions that are compatible with genuine constraints may be permitted.) The result so far, then, is a system of morality which yields deontological constraints that are tempered by thresholds and admit of exceptions in cases of, for example, self-defense and sanctions for wrong- doers, but do not admit of just any exception that will increase the overall good. Furthermore, these constraints and their exceptions are grounded in a common source: the bargainers’ twofold motivation.