The philosophical approach of this volume is mainly structuralist, using logical tools to investigate the formal structure of various kinds of objects in our world, as characterised by language and as systematised by philosophy. This volume mainly analyses the structural properties of collections or pluralities (with applications to the philosophy of set theory), homogeneous objects like water, and the semantics and philosophy of events. This book thereby complements algebraic work that has been done on other philosophical entities, i.e. propositions, properties, relations, or situations. Located in the triangle of language, logic and philosophy, this volume is unique in combining the resources of different ¹elds in an interdisciplinary enterprise. Half of the fourteen chapters of this volume are original papers, complementing the collection of the author's previously published essays on the subject.

Preface
Introduction
The logical analysis of plurals and mass terms: a lattice-theoretical approach
Plural
Hydras. On the logic of relative clause constructions with multiple heads
Generalized Quantifiers and Plurals
Je drei Äpfel - three apples each: Quantification and the German je
First-Order Axioms for the Logic of Plurality
Ten Years of Research on Plurals - Where Do We Stand?
The French Revolution - a Philosophical Event?
Algebraic Semantics of Event Structures
The Ontology of Individuals and Events
Quantity and number
Algebraic semantics for Natural Language: Some philosophy, some applications
Language and ontology
Mereology, Second-order logic, and Set theory
Appendix: A chapter in lattice theory.