This chapter first introduces one of the main ideas of the book — that the normativity of the intentional is the ‘key to metaethics’. It is suggested that this idea naturally captures a kind of Platonism about the normative. It then compares the theory that is outlined in the rest of the book with the best-known alternative theories (such as expressivist and constructivist theories, the theories built around a ‘conceptual analysis’ of normative concepts, the naturalist theory that is known as ‘Cornell moral realism’, and quietist forms of realism). Finally, it gives a summary of the contents of later chapters, and makes some comments on the philosophical method that is used in the rest of the book.
Keywords: metaethics, normativity, intentional, Platonism, expressivism, constructivism, conceptual analysis, naturalism, Cornell moral realism, quietism