In metaphilosophy and ethics, metaethics is the study of the nature, scope, ground, and meaning of moral judgment, ethical belief, or values. It is one of the three branches of ethics generally studied by philosophers, the others being normative ethics (questions of how one ought to be and act) and applied ethics (practical questions of right behavior in given, usually contentious, situations).
While normative ethics addresses such questions as "What should I do?", evaluating specific practices and principles of action, metaethics addresses questions about the nature of goodness, how one can discriminate good from evil, and what the proper account of moral knowledge is. Similar to accounts of knowledge generally, the threat of skepticism about the possibility of moral knowledge and cognitively meaningful moral propositions often motivates positive accounts in metaethics. Another distinction is often made between the nature of questions related to each: first-order (substantive) questions belong to the domain of normative ethics, whereas metaethics addresses second-order (formal) questions.
