Since ancient times, ontology, the analysis and categorisation of what exists, has been fundamental to philosophical enquiry. But, until recently, ontology has been seen as an abstract, purely theoretical discipline, far removed from the practical applications of science. However, with the increasing use of sophisticated computerised information systems, solving problems of an ontological nature is now key to the effective use of technologies supporting a wide range of human activities. The ship of Theseus and the tail of Tibbles the cat are no longer merely amusing puzzles. We employ databases and software applications to deal with everything from ships and ship building to anatomy and amputations. When we design a computer to take stock of a ship yard or check that all goes well at the veterinary hospital, we need to ensure that our system operates in a consistent and reliable way even when manipulating information that involves subtle issues of semantics and identity. So, whereas ontologists may once have shied away from practical problems, now the practicalities of achieving cohesion in an information-based society demand that attention must be paid to ontology.

Researchers in such areas as artificial intelligence, formal and computational linguistics, biomedical informatics, conceptual modeling, knowledge engineering and information retrieval have come to realise that a solid foundation for their research calls for serious work in ontology, understood as a general theory of the types of entities and relations that make up their respective domains of inquiry. In all these areas, attention is now being focused on the content of information rather than on just the formats and languages used to represent information. The clearest example of this development is provided by the many initiatives growing up around the project of the Semantic Web. And, as the need for integrating research in these different fields arises, so does the realisation that strong principles for building well-founded ontologies might provide significant advantages over ad hoc, case-based solutions. The tools of formal ontology address precisely these needs, but a real effort is required in order to apply such philosophical tools to the domain of information systems. Reciprocally, research in the information sciences raises specific ontological questions which call for further philosophical investigations.

The purpose of FOIS is to provide a forum for genuine interdisciplinary exchange in the spirit of a unified effort towards solving the problems of ontology, with an eye to both theoretical issues and concrete applications. In our call for papers, we asked for contributions reporting work in a wide range of areas, all of which are important to the development of formal ontologies:

Foundational Issues:

• Kinds of entity: particulars vs. universals, continuants vs. occurrents, abstracta vs. concreta, dependent vs. independent, natural vs. artificial

• Formal relations: parthood, identity, connection, dependence, constitution, subsumption, instantiation

• Vagueness and granularity

• Identity and change

• Formal comparison among ontologies

• Ontology of physical reality (matter, space, time, motion, …)

• Ontology of biological reality (genes, proteins, cells, organisms, …)

• Ontology of mental reality (mental attitudes, emotions, …)

• Ontology of social reality (institutions, organizations, norms, social relationships, artistic expressions, …)

• Ontology of the information society (information, communication, meaning negotiation, …)

• Ontology and natural language semantics, ontology and cognition, ontology and epistemology, semiotics

Methodologies and Applications:

• Top-level vs. application ontologies

• Role of reference ontologies; Ontology integration and alignment

• Ontology-driven information systems design

• Requirements engineering

• Knowledge engineering

• Knowledge management and organization

• Knowledge representation; Qualitative modeling

• Computational lexica; Terminology

• Information retrieval; Question-answering

• Semantic web; Web services; Grid computing

• Domain-specific ontologies, especially for: Linguistics, Geography, Law, Library science, Biomedical science, E-business, Enterprise integration

Out of the 76 papers submitted to FOIS-06, 29 were secected by the Programme Committee, with the help of a number of extra reviewers (listed in the following section on Conference Organisation). With few exceptions, all papers have been refereed by three experts. On behalf of the Organising Committee, we would like to thank the members of the Program Committee and additional reviewers for their careful work and constructive suggestions, which have helped us to produce a very high quality conference programme. We are also extremely grateful to the two invited speakers, Doug Lenat and Antony Galton, for enthusiastically agreeing to speak at FOIS. Finally, we would like to thank the Conference Chair, Nicola Guarino, the Local Chair, Bill Andersen, the Publicity Chair, Leo Obrst, the Website Administrator, Sira Greco, and Allan Third for help with editing the camera ready copy. The hard work and good will of all these people have contributed to the success of FOIS-06.

Brandon Bennett, Christiane Fellbaum