Naturalism is an important kind of Ethical Reductionism. It holds that all evaluative properties can be reduced to natural properties; in plain language “they are natural properties”. Such an ontological doctrine has also an epistemological side to the effect that our ethical beliefs can be justified empirically, and through such a justification ethical knowledge is at the same footing as scientific knowledge. This essay is a fulfillment of a promise I made before. This essay concludes that (a) explaining particular ethical beliefs as observations, drawing on the idea of “inferential chain,” is unsuccessful; for firstly it cannot explain how our belief in ethical properties as distinct from natural properties is justified in the first place...