Handling irresolvable conflicts in the Semantic Web: an RDF-based conflict-tolerant version of the Deontic Traditional Scheme

Abstract This paper introduces a computational ontology for deontic reasoning, fully implemented in RDF* and SPARQL*, designed to support reasoning in the presence of irresolvable conflicts. These are situations in which two or more norms prescribe incompatible obligations, prohibitions or permissions, without any clear priority among them. Existing approaches in formal deontic logic are typically limited to the propositional level, focused primarily on obligation as the central modality, and are rarely implemented in a way that is compatible with Semantic Web standards. The framework presented here addresses these limitations by providing a first-order, Resource Description Framework (RDF)-based formalization of all standard deontic modalities: obligations, permissions, optionality and their negations. It supports the explicit representation and reasoning about violations and conflicts while also accounting for contextual constraints. The ontology integrates contributions from three research areas that have so far largely developed in isolation: RDF-based LegalTech solutions, reification-based models of Natural Language Semantics and conflict-tolerant approaches in formal deontic logic. By incorporating contradictions and conflicts into the object language, the ontology supports advanced reasoning tasks within a framework that adheres to W3C standards. This makes it suitable for integration into industrial LegalTech applications where normative reasoning is required1.