E. J. Lowe, a prominent figure in contemporary metaphysics, sets out and defends his theory of what there is. His four-category ontology is a metaphysical system which recognizes four fundamental categories of beings: substantial and non-substantial particulars and substantial and non-substantial universals. Lowe argues that this system has an explanatory power which is unrivalled by more parsimonious theories and that this counts decisively in its favour. He showsthat it provides a powerful explanatory framework for a unified account of causation, dispositions, natural laws, natural necessity and many other related matters, thus constituting a full metaphysical foundation for natural science.
