Philosophical ethics includes two different domains.
It is a more recent phenomenon and has received its primary attention in this century. Metaethics is the examination of the logic and language of moral reflection, moral discourse, and moral action. The person doing metaethics does not make recommendations on how people should behave but rather seeks to gain insight on the nature of moral terms, on the logical structure and interrelatedness of moral assertions, and the like. Any recommendation offered by the metaethician would be on how we ought to view and use moral discourse. The reading by Ayer is an example of metaethics.