He is known especially for his work on moral realism and on David Hume's moral theory.

This form of moral realism is the view that moral facts are facts about nature.

However, I will not assume the truth of moral realism here.

This makes moral realism a non-nihilist form of cognitivism.

Within moral realism, the two main subdivisions are ethical naturalism and ethical non-naturalism.

However, on certain versions of the meta-ethical view called moral realism, moral facts are both descriptive and prescriptive at the same time.

He is a leading defender of a non-naturalistic moral realism, holding that moral statements are not reducible to natural terms.

However, both moral realism and ethical non-naturalism are not essential to the view; most ethical intuitionists simply happen to hold those views as well.

According to moral realism, such a sentence claims there to be some objective property of 'wrongness' associated with the act of murder.

The less-condemning attitude toward inappropriate behavior is a sign of the "moral realism" of the 1990's, some experts say.