A central feature of ethical thought is that it appears to involve not only descriptive belief, belief about what is the case, but also normative belief about what should be done. Suppose we take this at face value and understand normative thought in ethics to consist of attitudes that, at the most basic explanatory level, are genuine beliefs. What then should we say about the basic nature of the normative properties that such beliefs are about? I argue that normative properties are complex naturalistic properties of psychology. In the first chapter, I consider the non-naturalistic realist position, according to which our world contains the instantiation of irreducibly normative, metaphysically sui generis properties. I argue that proponent...