In many ways the theory of justice which Rawls developed and refined is not obviously any more promising as a basis for developing a theory of ecological justice than are those of Nozick and Walzer. It, too, seems to presuppose that justice is something which fundamentally can obtain only between fully fledged moral persons. As was the case with Nozick and Walzer, Rawls barely discusses the morality of relations between humans and non-humans. Also, Rawls and Nozick share at least one point in common, namely the Kantian starting point that justice concerns the relations between autonomous beings capable of mutual recognition as moral equals. However, it has from time to time appeared possible to find materials within Rawls’s approach to facilitate the construction of a theory of justice which allows a natural place for non-persons. To understand these possibilities we need to say a bit more about the development of Rawls’s ideas.