All except three of the papers in this volume were presented at the colloquium on "L'Ontologie formelle aujourd'hui", Geneva, 3-5 June 1988. The three exceptions, the papers by David Armstrong, Uwe Meixner and Wolfgang Lenzen, were presented at the colloquium on "Properties", Zinal, June 1-3, 1990. It was, incidentally, at the second of these two colloquia that the European Society for Analytic Philosophy came into being. The fathers of analytic philosophy - Moore and Russell - were in no doubt that ontology or metaphysics as well as the topics oflanguage, truth and logic constituted the core subject-matter of their "analytic realism", 1 for the task of metaphysics as they conceived things was the description of 2 the world. And logic and ontology are indissolubly linked in the system of the grandfather of analytic philosophy, Frege. After the Golden Age of analytic philosophy - in Cambridge and Austria - opposition to realism as well as the "linguistic turn" contributed for a long time to the eclipse of ontology. 3 Thanks in large measure to the work of some of the senior contributors to the present volume - Roderick Chisholm, Herbert Hochberg, David Armstrong and Karel Lambert - ontology and metaphysics now enjoy once again the central position they occupied some eighty years ago in the heyday of analytic philosophy.

Inhalt
The Basic Ontological Categories.- 1. Introduction.- 2. The Basic Concepts.- 3. Individual Things and Events.- 4. Beginnings and Processes.- 5. Necessary Substance.- Properties.- 1. Why We Should Admit Properties.- 2. Universals vs. Tropes.- On Negative and Disjunctive Properties.- Particulars, Individual Qualities, and Universals.- Characteristica Universalis.- 1. Preamble.- 2. From Leibniz to Frege.- 3. Directly Depicting Diagrams vs. Existential Graphs.- 4. Some Conditions on a Directly Depicting Language.- 5. The Oil-Painting Principle.- 6. Primitives and Definitions.- 7. Substance.- 8. Accidents.- 9. Sub-Atoms (Mutually Dependent Parts of Atoms).- 10. Boundaries and Boundary Dependence.- 11. Universals.- Definite Descriptions and the Theory of Objects.- 1. A New Explanation.- 2. An Application of the Foregoing Explanation.- Truth Makers, Truth Predicates, and Truth Types.- Worlds and States of Affairs: How Similar Can They Be?.- 1. Motivation.- 2. Salmon's Counterexample.- 3. TheBranching Conception.- Was Frege Right about Variable Objects?.- Logical Atomism and Its Ontological Refinement: A Defense.- 1. Introduction.- 2. Logical Atomism, What.- 3. Examples of the Avoidance of Unnecessary Facts.- 4. Disputed Case I: Negative Propositions.- 5. Disputed Case II: Universal Generalization.- 6. Other Higher Order Functors.- 7. Statistical Generalizations and Probability.- 8. Laws of Nature and Causality.- 9. Applied Mathematics, Dispositions, and Others.- 10. Resolution and Ultimate Facts.- 11. Concluding Remarks.- Intentionality and Tendency: How to Make Aristotle Up-To-Date.- 1. Introduction.- 2. The Problem.- 3. Aristotle.- 4. Newtonian Self-Change.- 5. Intentionality.- 6. Temporally Extended Entities.- 7. The Duality of Intentions.- 8. Formal Ontology Today.- 9. Summary.- Leibniz on Properties and Individuals.- Index of Names.- Index of Subjects.