XIII—The Definition of Good: Moore's Axiomatic of the Science of Ethics

Abstract

MooRE's doctrine of the indefinability of good has occasionally been misunderstood as meaning that good is indefinable because it is not clear; indeed, that it could not be clear because it is not accessible to rational understanding. Even Moore himself, for a very short moment in his life,' doubted that it was; and thus faltered in his intuition of the self-evident clarity of this notion. With this one exception, however, he steadfastly kept to the conviction expressed in Principia Ethica, that the notion of good is so simple as to be incapable of proof, so transparently clear as to be in no need of proof, so self-evident as to be understood as soon as it is mentioned,2 so unique as to belong to nothing but Ethics, and so fundamental as to serve as basic for a systematic science. Anyone familiar with the concept of a systematic science ought, on reading Moore's account, immediately to conclude that his notion of good had all the characteristics of an axiom, and that all that were needed to bring about the systematic science of Ethics would be to articulate this notion so as to form this axiom, and to deduce the science from it. But nobody, so far, has