 If law aims to settle disputes about moral issues, then law must be identifiable without resolving these same disputes. The law is therefore exhausted by its sources (such as legislative enactments, judicial decisions, and customs, together with local conventions of interpretation). This kind of argument has been generalized (see Shapiro 1998), but also subjected to criticism. It is uncertain what sort of constraint is posed by the idea that it should not involve “the very same issues”—perhaps if morality is a necessary condition only there could be moral tests for authority that leave the relevant dependent reasons untouched (Coleman 2001: 126–127). And while law does indeed serve as a scheme for guiding and appraising behaviour, it may also have other functions, such as educating its subjects about right and wrong, and this may be ill-served the attitude that the rules are to be obeyed in part because they are the rules (Waluchow 1994).