Moral skepticismMoral skepticism (or moral scepticism in British English) is a class of meta-ethical theories all members of which entail that no one has any moral knowledge. Many moral skeptics also make the stronger, modal claim that moral knowledge is impossible. Moral skepticism is particularly opposed to moral realism: the view that there are knowable and objective moral truths. Some defenders of moral skepticism include Pyrrho, Aenesidemus, Sextus Empiricus, David Hume, J. L.
Moral realismMoral realism (also ethical realism) is the position that ethical sentences express propositions that refer to objective features of the world (that is, features independent of subjective opinion), some of which may be true to the extent that they report those features accurately.
Moral relativismMoral relativism or ethical relativism (often reformulated as relativist ethics or relativist morality) is used to describe several philosophical positions concerned with the differences in moral judgments across different peoples and cultures. An advocate of such ideas is often referred to as a relativist for short. Descriptive moral relativism holds only that people do, in fact, disagree fundamentally about what is moral, with no judgment being expressed on the desirability of this.
Ethical naturalismEthical naturalism (also called moral naturalism or naturalistic cognitivistic definism) is the meta-ethical view which claims that: Ethical sentences express propositions. Some such propositions are true. Those propositions are made true by objective features of the world. These moral features of the world are reducible to some set of non-moral features. The versions of ethical naturalism which have received the most sustained philosophical interest, for example, Cornell realism, differ from the position that "the way things are is always the way they ought to be", which few ethical naturalists hold.
MetaethicsIn metaphilosophy and ethics, metaethics is the study of the nature, scope, and meaning of moral judgment. 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).
