Metaethics is the study of the foundations of ethics, particularly in the philosophy of language, the philosophy of mind, epistemology, and metaphysics. Metaethical realism is a position that maintains a judgment like ?it is wrong to betray a friend? is true or false (philosophy of language), is a function of the mind?s ability to represent facts about the world (philosophy of mind) that are mind-independent (epistemology), and which is made true or false by reality (metaphysics). Metaethical expressivism by contrast maintains that such judgments are not true or false in the normal sense, are expressions of our attitudes that we come to on the basis of practical reasoning, and which reveal facts about cognition rather than truths about a mind-independent reality. This course examines classical and contemporary versions of these two positions in metaethics.