‘Try to imagine Nowheresville – a world very like our own except that no one, or hardly anyone…has rights’. This is the thought experiment conducted by the philosopher Joel Feinberg at the beginning of his essay on ‘The Nature and Value of Rights’. Surely such a world would be a deficient one from the moral point of view. Perhaps it would even be a wicked or iniquitous society, an anarchic place where life is nasty, brutish and short. But let us not jump to this conclusion too readily. Feinberg is quite willing to allow many other moral features of great respectability to exist in Nowheresville. ‘In particular, let the virtues of moral sensibility flourish. Fill this imagined world with as much benevolence, compassion, sympathy and pity as it will conveniently hold without strain.’

Go even further, Feinberg suggests. Take into account the Kantians who insist on the idea of moral duty and include such an idea as motive for moral behaviour in our imaginary society. But maybe we have now gone too far. Maybe the introduction of duties has also brought in by the back door the idea of rights, due to the important and widely held doctrine of the correlativity of rights and duties. If people have duties, then there must be corresponding people who can claim these duties. But this does not necessarily hold. Not every duty has a correlative right, as we shall argue later, and the correlativity doctrine is not as tidy as some think.