In his book What We Owe to Each Other, Thomas Scanlon proposes what he calls a ‘contractualist’ explanation of what he describes as ‘a central part of the territory called morality’, i.e. our duties to other rational creatures. If Scanlon is right, the fact that another creature is rational generates a particular kind of moral constraint on how we may act towards it: one should ‘treat rational creatures only in ways that would be allowed by principles that they could not reasonably reject insofar as they too were seeking principles of mutual governance which other rational creatures could not reasonably reject . This is then used to explain what makes actions right, at least within his central moral area. Such actions will be right because ...