Concept Graphs with Cuts as Diagrammatic First Order

In the research field of diagrammatic reasoning, there are some attempts for providing diagrammatic forms of logic. Probably the most important one is Sowa's system of conceptual graphs from which Sowa claims that they have at least the expressiveness of first order predicate logic (FOPL). But a closer observation shows that their definitions lack (mathematical) preciseness, which yields several ambiguities, gaps and flaws. In my dissertatio