Survey of philosophical views on the character and status of events; by Roberto Casati and Achille Varzi.

Survey of attempts to draw the distinction between concrete and abstract objects; by Gideon Rosen.

Information on ontology, on the history of ontology, and on contemporary ontology and its applications.

An extensive resource site on the development of ontology, especially in the twentieth century.

By Barry Miller.

Short article by Roberto Casati of the École Polytechnique and Achille C. Varzi of Columbia.

Forum for discussion and study of the Metaphysics of Quality as proposed by Robert M Pirsig in his books Lila: An Inquiry into Morals and Zen and the Art of Motorcycle Maintenance.

Paper by Axel Randrup defending idealism and arguing that materialism leads to logical contradictions, which closes by considering the implications of this for religion.

Aims to establish that conscious experience involves non-physical properties. It is one of the most discussed arguments against physicalism; by Martine Nida-Rümelin.

Discussion of the thesis that everything is physical; by Daniel Stoljar.

A principle of analytic ontology first explicitly formulated by Leibniz. It states that no two distinct substances exactly resemble each other.

An article describing tropes; by John Bacon.

On the nature of consciousness - looking for soul in a soulless world.

Notes on the relational element in the assertion that things exist. Patterned on Wittgenstein's Philosophical Investigations.

Collected definitions, from leading philosophical reference works and from philosophers from Wolff to Husserl.

Sequence of short essays on this topic.