Ethical reasoning of all types is anthropocentric, in that it is addressed to agents, but anthropocentric starting points vary in the preference they accord the human species. Realist claims about environmental values, utilitarian reasoning and rights-based reasoning all have difficulties in according ethical concern to certain all aspects of natural world. Obligation-based reasoning can provide quite strong if incomplete reasons to protect the natural world, including individual non-human animals. Although it cannot establish all the conclusions to which anti-speciesists aspire, it (...) may establish many of them with some clarity. (shrink)