Some theorists believe that there is a plurality of values, and that in many circumstances these values are incommensurable, or at least incomparable. Others believe that all values are reducible to a single super-value, or that even if there is a plurality of irreducible values these values are commensurable. But I will argue that both sides have got it wrong. Values are neither commensurable nor incommensurable, at least not in the way most people think. We are free to believe in (...) incommensurability or not, depending on what particular conception of morality we want to embrace. Incommensurability is accordingly not a theory about value. It is a presupposition that provides a necessary background condition for a certain kind of value to exist. It is therefore not the kind of view that can be morally true or false. As a presupposition, it can only be accepted or rejected on grounds that do not presuppose that morality already exists. Incommensurability is, like the rejection of hard determinism, one of the presuppositions on which morality as we know it happens to be based. (shrink)

In this commentary on Darrel Moellendorf’s Mobilizing Hope: Climate Change & Global Poverty (Oxford: Oxford University Press, 2022), I discuss his use of the precautionary principle, whether his hope for climate-friendly ‘green growth’ is realistic given the tendency for inequality to accelerate as it gets higher, and what I call his assumption of a liberal baseline. That is, I worry that the audience to whom the book is addressed are those who already accept the environmental and economic values to which (...) Moellendorf appeals, while those who are blocking effective action on climate change in fact reject those values and are therefore unlikely to be moved by the arguments the book presents. (shrink)