Normative ethics asks, "What makes 'murder is wrong' a true statement? Happiness for the greatest number of people? Sense of duty?"
In contrast, meta-ethics asks, "What kind of statement is 'murder is wrong?' Does it even express a fact at all, or just a grunt of personal emotion?"
II. "Murder is wrong" expresses a true (or false) fact
If moral statements express true or false statements, then this theory is called cognitivism. Cognitivism further splits into:
- Moral realism: Moral statements express facts about the world, independent of anyone's opinion or any group or societal opinion.
- Moral non-realism: While moral statements do express facts, they are just made true by subjective opinions of people, either at the individual or societal level.
Moral statements are just expressions of emotion, or of commands. This theory is called non-cognitivism. "Murder is wrong" really means "Blech! Murder!" or "Don't murder!" Note how neither one of these statements can be true or false.
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