Positive Thesis
The non-cognitivist requires the positive thesis because they owe us Moral Language Moral sentences express attitudes or commands When you assert a moral statement, what you imply is a expression of Reaction or expression of a Commands. E.g:
- Killing is wrong. Actually is a command “Boo, killing, booo, yuck!”
Negative Thesis
Moral sentences are not truth-apt Realist can accept the positive thesis (moral statements can express 2+ ideas at the same time). It is the negative thesis that is the point of disagreement