Scholarly AI system diagrams as an access point to mental models

Complex systems, such as Artificial Intelligence (AI) systems, are comprised of many interrelated components. In order to represent these systems, demonstrating the relations between components is essential. Perhaps because of this, diagrams, as "icons of relation", are a prevalent medium for signifying complex systems. Diagrams used to communicate AI system architectures are currently extremely varied. The diversity in diagrammatic conceptual modelling choices provides an opportunity to gain insight into the aspects which are being prioritised for communication. In this philosophical exploration of AI systems diagrams, we integrate theories of conceptual models, communication theory, and semiotics. We discuss consequences of standardised diagrammatic languages for AI systems, concluding that while we expect engineers implementing systems to benefit from standards, researchers would have a larger benefit from guidelines.