Published online by Cambridge University Press: 13 April 2010
David Brink has recently argued for the “parity” of ethics and the sciences. While the parity claim alone might be metaphysically neutral, Brink favours a form of ethical naturalism on which moral properties “are” natural properties, just as non-moral macrophysical properties “are” the microphysical states that compose them. Brink supports this claim by showing that both types of properties share certain important features: specifically, that both may be (and typically are) constituted, supervening and synthetically necessitated. I shall argue that notwithstanding these common features, there remain significant modal differences in the way the two types of properties are assigned to the world. These differences represent an important respect in which moral properties are not on par with their scientific counterparts.