The semantic thesis: Moral statements have meaning, they express propositions, or are the kind of things that can be true or false.
# The alethic thesis: Some moral propositions are true.
# The metaphysical thesis: The metaphysical status of moral facts is robust and ordinary, not importantly different from other facts about the world.

Moral anti-realism is the denial of at least one of these claims. Ethical subjectivists deny the third claim, instead arguing that moral facts are not metaphysically ordinary,