Suggestions for extending the FAIR Principles based on a linguistic perspective on semantic interoperability.

FAIR (meta)data presuppose their successful communication between machines and humans while preserving meaning and reference. The FAIR Guiding Principles lack specificity regarding semantic interoperability. We adopt a linguistic perspective on semantic interoperability and investigate the structures and conventions ensuring reliable communication of textual information, drawing parallels with data structures by understanding both as models. We propose a conceptual model of semantic interoperability, comprising intensional and extensional terminological interoperability, as well as logical and schema propositional interoperability. Since there cannot be a universally accepted best vocabulary and best (meta)data schema, establishing semantic interoperability necessitates the provision of comprehensive sets of intensional and extensional entity mappings and schema crosswalks. In accordance with our conceptual model, we suggest additions to the FAIR Guiding Principles that encompass the requirements for semantic interoperability. Additionally, we argue that attaining FAIRness of (meta)data requires not only their organization into FAIR Digital Objects, but also the establishment of a FAIR ecosystem of FAIR Services, that include a terminology, a schema, and an operations service.