Clausal Form Logic, formal system, graph, Graph-based Clausal Form Logic, RDF model, Fuzzy logic, Fuzzy predicate logic.

This paper follows the work of T. Richards specialization Clausal Form Logic (CFL) formal system of the first order logic. The paper presents also the way of using graph-based clausal form statements in the frame of fuzzy semantic networks. The goal of our research is to follow the direction towards graph-based clausal form knowledge representation shaped by Richards and build up a fuzzy graph-based formal system. The new formal system Fuzzy Graph-based Clausal Form Logic (FGCFL) has its own graph-based language with the expressivity similar to that one of CFL and enriched Fuzzy logic (implementation of fuzzy logic increases expressivity). The idea of the FGCFL graph-based approach is also useful in the frame of the fuzzy RDF model especially in its graph version.