This paper argues for a distinction between two classes of ergative-absolutive languages, one in which absolutive corresponds to nominative case, and the other in which absolutive corresponds to a morphological default, masking abstract nominative case on the intransitive subject and abstract accusative case on the transitive object. The author argues that abstract case is imperfectly realized as morphological case according to the Elsewhere Principle. Languages examined include Georgian, Warlpiri, Niuean, Enga, and the Pama-Nyungan languages Djapu, Kugu Nganhcara, and Margany.