In my view, disciplines arise in response to problems and the boundaries between them have whatever rationale they possess to the degree that different problems can be handled separately from one another. The difficulty lies in the problems themselves with which political philosophy typically deals, particularly when the idea of justice comes into play. Let us say, in again a rather vacuous phrase, that political philosophy consists in systematic reflection about the nature and purpose of political life. Nothing puzzling in that, it would seem. Yet political philosophers have tended to tackle this subject in two quite different ways, depending on how they position themselves with regard to the domain of morality.