For decades, roles have been discussed and applied in different ways in various fields of computer science, but apparently no consensus on their understanding is available. Thus, role terms like “patient”, “runner”, or “factor” qualify for further investigation, which aims at covering and generalizing recurrent understandings and uses of roles. The generality of roles suggests their inclusion in top-level ontologies. This paper extends and refines analyses of roles for the top-level ontology General Formal Ontology (GFO). The primary foundation of this (...) account comprises the notions of role, player, and context and their interrelations, associated with situations of, for instance, some human who plays a patient role in a hospital context. Further, a classification of roles is introduced, which at top distinguishes two role types: abstract roles, providing a means of viewing something in a context, and social roles, which are complex social objects in vaguely defined contexts. These types are mixed in the literature, and their differences restrict the theory common to all roles. Based on this framework, the paper discusses controversial issues of roles, demonstrating the expressiveness of the overall account, which allows for fine-grained distinctions and the integration of prior work. (shrink)

The General Formal Ontology (GFO) is a top-level ontology that is being developed at the University of Leipzig since 1999. Besides introducing some of the basic principles of the ontology, we expound axiomatic fragments of its formalization and present ontological models of several use cases. GFO is a top-level ontology that integrates objects and processes into a unified framework, in a way that differs significantly from other ontologies. Another unique selling feature of GFO is its meta-ontological architecture, which includes set (...) theory into ontology and which accounts for its specific role in common representation approaches. The second level of that architecture starts from the distinction of categories and individuals, which forms the backbone of the world’s structure. Furthermore, GFO comprises several kinds of categories, among them universals and concepts, and it considers several ontological regions and levels. In the context of this special issue paper, we study five pre-determined use cases from the perspective of GFO. The results of these analyses yield insights into how the ontology treats several important notions. Very abridged, this covers material objects and their composition; roles and social entities; properties with their relations to objects and processes, and their changing; changes of processes, including a functional perspective; and, eventually, the nature and changing of concepts as well as terminology. A final part summarizes application projects that use GFO in various contexts. (shrink)