Abstract
In his book A Theory of Justice, John Rawls introduces and employs the concept of “reflective equilibrium” as a method of testing which of rival moral theories is to be preferred. The introduction of this concept is plainly a significant event for moral philosophy. The criterion by which we decide to reject, say, utilitarianism in favour of a contractual theory of justice is, if anything, even more fundamental than the choice of theory itself, since our choice of moral theory may well be determined by the criterion we use.