Metaethics is the most abstract area of moral philosophy. It doesn’t ask what acts, or what kind of acts are good or bad, right or wrong; rather, it asks about the nature of goodness and badness, what it is to be morally right or wrong.
Moral Realism and Antirealism
Perhaps the biggest controversy in metaethics is that which divides moral realists and antirealists.
Moral realists hold that moral facts are objective facts that are out there in the world. Things are good or bad independent of us, and then we come along and discover morality.
Antirealists hold that moral facts are not out there in the world until we put them there, that the facts about morality are determined by facts about us. On this view, morality is not something that we discover so much as something that we invent.
Cognitivism and Noncognitivism
Cognitivism and noncognitivism are theories of the meaning of moral statements.
According to cognitivism, moral statements describe the world. If I say that lying is wrong, then according to the cognitivist I have said something about the world, I have attributed a property wrongness to an act lying. Whether lying has that property is an objective matter, and so my statement is objectively either true or false.
Noncognitivists disagree with this analysis of moral statements. According to noncognitivists, when someone makes a moral statement they are not describing the world; rather, they are expressing their feelings or telling people what to do. Because noncognitivism holds that moral statements are not descriptive, it entails that moral statements are neither true nor false. To be true is to describe something as being the way that it is, and to be false is to describe something as being other than the way that it is; statements that aren’t descriptive can’t be either.