 The shortcomings of utilitarianism have prompted several recent philosophers to revive the old idea of the social contract as a better way of bringing coherence to our thinking about justice. The idea here is not that people actually have entered a contract to establish justice, or that they should proceed to do so, but that we can understand justice better by asking the question: what principles to govern their institutions, practices and personal behaviour would people choose to adopt if they all had to agree on them in advance? The contract, in other words, is hypothetical; but the search for agreement is meant to ensure that the principles chosen would, when implemented, not lead to outcomes that people could not accept. Thus whereas a utilitarian might, under some circumstances, be prepared to support slavery – if the misery of the slaves were outweighed by the heightened pleasures of the slave-owners – contractarians claims that no-one could accept a principle permitting slavery, lest they themselves were destined to be slaves when the principle was applied.