Addressing inequities that result from interactions between economic activity and large-scale ecological processes requires a theory of justice that takes into account how those interactions affect relative social position-the distribution of benefits and burdens in a society. For theorist John Rawls, the evaluation of relative social position is based on certain "primary goods"-consisting of rights and liberties, powers and opportunities, and income and wealth. In contrast, Martha Nussbaum bases this evaluation on central human functional capabilities, or conditions that make it possible for people to achieve things, such as "being able to have good health" and "being able to move freely from place to place." While some of Nussbaum's "capabilities" address the same "goods" that concern Rawls, income and wealth play a less central role in her theory. A person's capabilities, Nussbaum argues, are what indicate whether circumstances will allow that person to translate the things he or she has into actual achievements. Nussbaum's approach rightly suggests that identifying injustice in the distribution of benefits and harms that result from human interactions with the environment ultimately requires assessing how environmental conditions affect people's capacities. Such a theory of justice would certainly help societies as they face the real conflict between protecting environmental conditions necessary for basic capabilities and engaging in certain kinds of economic productivity.