If the natural environment is in the precarious state to which many attest, what would this demand of us? What duties are suggested by the observation that our collective behavior threatens the planet, even if no particular individual intends harm? Can we legitimately ask those who sincerely hold little or no interest in the long-term viability of the earth s ecosphere to value it in the same way as committed environmentalists do and to act accordingly? In The Moral Weight of Ecology: Public Goods, Cooperative Duties, and Environmental Politics, Edward Tverdek engages these questions and ultimately argues that the demands of ecology upon all of us are in fact quite substantial. The book is not, however, another study in environmental ethics, examining what it if anything we owe the natural world. Rather, The Moral Weight of Ecology addresses the matter from the perspective of political economy and social choice theory. Tverdek seeks to disarm both the intuitive libertarian notion that no one should be compelled to value and contribute toward something for which she has little regard as well as the romantic environmentalist assertion that one cannot assign an economic value to nature. We must in some way price the natural world, Tverdek argues, but how we do so necessarily depends on what we believe would be a fair way to distribute the costs and burdens of maintaining it, and these moral beliefs must be antecedent to the consumer preferences economists consider the raw data for determining the value of the environment."