Dear Robert, I believe you are right. I think one needs to go beyond market valuations and utilitarianism more in general to find better rationales for protecting the biosphere. In this respect, I personally like Micheal Sandel who in his book about justice (What is the right thing to do?) appeals to Aristotle philosophy and the role of "telos" (purpose). At the same time I find the contribution of John O'Neill an extremely important one (specifically regarding environmental policy). The key point is that we cannot rely on utilitarianism and market valuation in order to find rationales for protecting nature. Instead we need to exert collective value judgement engaging in collective deliberation.