 One way to loosen up our thinking about justice is by paying greater attention to the history of the concept. We can learn a great deal by reading what Aristotle, or Aquinas, or Hume, has to say about the concept, but as we do so, we also see that elements we would expect to find are missing (there is nothing about rights in Aristotle, for example), while others that we would not anticipate are present. This may in some part be due to the idiosyncrasies of each thinker, but more importantly it reflects differences in the form of social life in which each was embedded – its economic, legal and political structure, especially. Various attempts have been made to write histories of justice that are more than just catalogues of what individual thinkers have said: they aim to trace and explain systematic shifts in the way that justice has been interpreted (for contrasting examples, see MacIntyre 1988, Fleischacker 2004, Johnston 2011). These should not be read as enlightenment stories in which our understanding of justice steadily improves as the centuries roll by. MacIntyre’s view, for example, is that modern liberal societies cannot sustain the practices within which notions of justice find their proper home. We can get a better grasp of what justice means to us by seeing the various conceptions that compete for our attention as tied to aspects of our social world that did not exist in the past, and are equally liable to disappear in the future.