Abstract

This paper raises an objection to two important arguments for reductive ethical naturalism. Reductive ethical naturalism is the view that ethical properties reduce to the properties countenanced by the natural and social sciences. The main arguments for reductionism in the literature hold that ethical properties reduce to natural properties by supervening on them, either because supervenience is alleged to guarantee identity via mutual entailment, or because non-reductive supervenience relations render the supervenient properties superfluous. After carefully characterizing naturalism and reductionism, we will present, explain, and raise objections against each of the main reductionist arguments: that supervenience does not support the claim that ethical properties and their subvenient natural properties are mutually entailing; that reductive views undermine the claim that ethical properties yield resemblance; and that supervenience does not entail that non-descriptive ethical properties are superfluous in the most fundamental sense.