The move from good to ought, a premise form found in many justifications of environmental ethics, is itself in need of justification. Of the potential moves from good to ought surveyed, some have considerable promise and others less or none. Those without much promise include extrapolations of obligations based on human goods to nonsentient natural entities, appeals to educated judgment, precautionary arguments, humanistic consequentialist arguments, and justifications that assert that our obligations to natural entities are neither directly to those entities (...) nor derived from our obligations to humans. Some arguments that extrapolate obligations based on goods involving sentience from humans to sentient animals are promising, but whether they are sufficient is controversial. Gandhian andAristotlian arguments are also promising, provided we can justify their ought premises. (shrink)