The 10th Anniversary of the Joint Ontology Workshops (JOWO): Volume 1

The aim of this special issue is to celebrate the Joint Ontology Workshops (JOWO), the flagship event of the International Association for Ontology and its Applications (IAOA) dedicated to workshops on formal and applied ontology. With its 2024 edition, JOWO reached its first double-digit anniversary. To mark this milestone for the community of applied ontology researchers, this special issue invited authors of papers presented across these 10 editions to contribute extended and updated versions of their original works, showcasing how ideas first presented at JOWO have evolved and matured over time.

Since its first edition, JOWO has served as an umbrella event bringing together workshops that explore the many dimensions of formal and applied ontology. Applied ontology, an inherently interdisciplinary branch of knowledge representation, employs ontological analysis to tackle practical, real-world applications across a broad range of domains. As ontological analysis and methods can be applied to virtually any aspect of reality, the thematic breadth of JOWO is inherently extensive. By welcoming workshops from across the spectrum of ontology-related research, JOWO has developed into a broad and interdisciplinary venue that supports exchange between disciplines. Over the past decade, it has hosted contributions ranging from foundational issues in logic, philosophical ontology, and linguistics to applied research connecting ontology with cognitive science, conceptual modeling, robotics, natural language processing, and, more generally, artificial intelligence. In this way, JOWO has evolved in parallel with research trends, maintaining its role as a meeting point for diverse perspectives within the ontology community.

The JOWO Anniversary Special Issue was announced at the 10th JOWO edition, which was held in Enschede, the Netherlands. Mirroring the spirit of JOWO, this Special issue was intentionally open in scope, welcoming extended versions of any paper originally presented at JOWO and that had not yet appeared in a journal publication. Authors first submitted a short proposal consisting of an abstract of their intended contribution and the original JOWO publication. From these, a selection was made based on the impact of the original work, their adherence to the special issue’s inclusion criteria, and the diversity of workshops and research areas represented. Authors of the selected proposals were then invited to submit full papers. To further recognize excellence within the community, the “Best of JOWO Award” was initiated at JOWO 2024. The winners of the first “Best of JOWO” award were Anton Gnatenko, Oliver Kutz, and Nicolas Troquard with their paper “Building an Ontology of Computational Complexity.” This paper was fast-tracked through the initial proposal phase, and its extended version will be included in the second volume of this special issue.

In the full paper reviewing phase, each submission was evaluated by at least two reviewers with expertise in the paper’s subject domain, after which those submissions that received a revision recommendation went through a final revision and feedback round.

The process resulted in a two-volume Special Issue. This first volume gathers five contributions that reflect the diversity of research within the JOWO community, starting with three contributions originally presented at the Workshop on Foundational Ontology (FOUST).

The volume opens with “Approximating DOLCE in OWL: The DOLCEbasic and DOLCEnaryRel Core Modules,” first presented in Porello et al. (2024) at FOUST in 2024 and extended into the journal version by Daniele Porello, Walter Terkaj, Laure Vieu, Emilio M. Sanfilippo, and Francesco Compagno. The paper proposes a modular approach to render the foundational ontology DOLCE in OWL2, introducing DOLCEbasicOWL, a module providing the taxonomy together with DOLCE binary relations, which can be more simply accommodated in OWL; and DOLCENaryRel, the module dealing with the n-ary relations of the foundational ontology. In proposing this modular approach, the paper reflects on the challenges of translating expressive logical theories into a language suitable for implementation, such as OWL, that clearly imposes limitations on the allowed expressivity, and discusses the ontological choices to overcome these limitations.

Another FOUST descendant is the paper “How Information Complies with a Template: A Dual Mereological System,” first presented in Barton et al. (2022) at FOUST 2022 and here extended by Adrien Barton, Laure Vieu, and Jean-François Ethier. The paper offers a formal and ontological account of templates—informational entities that specify structural properties and constraints for the information content entities that comply with them. Building upon their previous work on the mereology of informational entities, the authors introduce a dual mereological framework that captures the correspondence between placeholders in templates and the slots of their fillers. Unlike earlier proposals, the theory preserves the slot structure of templates even after they are filled, providing a refined model for understanding how informational structures align with their content.

The final FOUST (2021) paper of this volume—originally presented in Masolo et al. (2021)—is “An Observational Approach to Representing Interpretation,” proposed in its extended version by Claudio Masolo, Emilio M. Sanfilippo, Emanuele Bottazzi, Roberta Ferrario, Alessandro Mosca, and Marta M. Vilardo. The paper proposes a formal theory to model observations about literary texts that is, virtually, applicable to different kinds of information. Importantly, the theory allows for the comparison of observations made by different observers about the same piece of information, thus allowing comparison of differences and commonalities between observations, also taking into account the subjective perspective of the different observers. This serves to ground ontology of interpretations of literary texts, with applications in Digital Humanities.

The fourth paper of this volume, “Metamodel Driven Information Systems as Vehicles for Ontology Discovery and Modelling” by Avi Shaked, was first presented as an extended abstract at Semantic Shield: The International Workshop on Modeling for Cybersecurity in 2024. The paper offers a reflection on metamodel-driven system development as an applied methodology for developing ontologies, showcasing, in retrospect, the development of a security modeling tool as a case in point. Among the major contributions of the paper is the demonstration of how ontological thinking supports iterative tool design and domain understanding, illustrating the value of ontological methods in practical system development.

The volume closes with “An Ontology of Exceptions for Knowledge Representation,” which was first proposed in Sacco et al. (2023) by the authors Gabriele Sacco, Loris Bozzato, and Oliver Kutz, at the Cognition and Ontology workshop in 2023 (CAOS VII). The paper proposes a framework to ground the comparison of different defeasible reasoning systems. Specifically, the goal of the paper is to provide a road map to guide the choice of an appropriate formalism for different applications in ontology design. In doing so, the paper also offers a systematic discussion of the notion of exceptionality, offering a thorough ontological analysis of different kinds of exception.

Together, these five contributions capture the breadth and richness of the JOWO community, illustrating how foundational and applied ontology continue to evolve through dialogue across domains, from logical and theoretical modeling to practical applications in information systems, knowledge representation, and the humanities.

A second volume of this special issue will follow next year, featuring additional extended contributions from JOWO’s 10-year history. In our forthcoming editorial for the second volume, we will further reflect on and look back at the evolution of the JOWO workshops and on the emerging research directions in the ontology community that they continue to inspire.