How can ‘we’ all live well together on one planet with a finite amount of ecological space crucial for life? While a mass extinction is underway, it seems that the pronoun ‘we’ can no longer merely refer to humanity. As previously introduced, over the last two decades a new body of literature has sprung up that tries to tackle this problem – either directly or indirectly – via evoking some understanding of justice (such as Baxter 2005, Nussbaum 2006, Schlosberg 2007). Because an account of justice to nonhumans in whichever form is a considerable addition to a position that attributes moral considerability to nonhumans, it is met with resistance from outside as well as within environmental philosophy. At best it is a widely held suspicion against the idea that justice is applicable to nonhumans; at worst it is an outright rejection that justice as a concept can expand beyond the human community. Thus, after having discussed in Chapter 2 that nonhuman living beings are morally considerable, this chapter will elaborate on the theoretical basis of interspecies justice to show that it is more than just a slogan.

Recall the distinction between ethical arguments and arguments about justice; this distinction remains true outside the human realm. For example, a convincing argument against fox hunting because it causes the foxes suffering does not automatically lead to the claim that these animals are entitled to a certain amount of space and food in order for their situation to be distributively just. In order to make a strong case for ecological justice, it is necessary to maintain a clear distinction between the realm of ethics and the more particular realm of justice. As previously discussed, this distinction between ethics and justice also indicates that a theory of ecological justice is part of, and not a substitution for, a more general theory of environmental ethics. In other words, all issues of justice are part of the realm of ethics but not all ethical considerations can be framed as problems of justice. Consequently, moral considerability is a necessary, but not sufficient, criterion for being a holder of entitlements of justice.