Abstract

In his paper How to Be a Moral Realist Boyd attempts to show how cases of ethical indeterminacy can be accounted for from an ethical realist’s standpoint. Boyd describes cases of extensional vagueness in the life-sciences which arise from knowable and definite underlying structures and draws an analogy to ethics to argue his case. This paper argues that an equally compelling analogy can be drawn between another type of scientific indeterminacy – that in quantum mechanics – and the related ethical cases. Because quantum mechanical uncertainty is a real and not merely epistemic limitation on physical description, it cannot be explained by reference to an underlying real structure. Thus this new analogy, where it seems valid, provides an argument for ethical antirealism in describing indeterminate ethical situations.