When do humans extend their ethical scope to include nature? Anthropocentrism and ecocentrism are two ways of understanding an extension of ethics to nature. In an anthropocentric ethic nature deserves moral consideration because how nature is treated a¡ects humans. In an ecocentric ethic nature deserves moral consideration because nature has intrinsic value. In two experiments participants (n = 91 and 84) generated moral reasoning responses to ecological moral dilemmas. The reasoning was coded as ecocentric, anthropocentric, or nonenvironmental (i.e., social contracts, truthfulness). Individual di¡erences and situational variables were examined in relation to moral reasoning about ecological dilemmas. Pro-environmental attitudes were related to more ecocentric and anthropocentric and less nonenvironmental reasoning. The presence of information about the impact of ecological damage on the environment, especially a more ‘‘wild’’ environment, elicited more ecocentric reasoning, while the presence of a social commitment elicited more nonenvironmental moral reasoning. The implications of the research for con£icts over environmental commons dilemmas are discussed.