Getting Closer to Iconic Logic

Visual and non-symbolic representational systems are increasingly important in logic, computing and cognitive sciences. Peirce proposed a logic for representing and reasoning about “actions of the mind in thought” using iconic signs, in other words to represent the connections and similarities exhibited in the relationships that exist, on the one hand, in the representational system, and, on the other, in the objects being so represented. The proposed means towards that end was the system of icons that employs the diagrammatic logic of Existential Graphs. Some of the key notions of his systems are explored and placed into the context of our cognitive and computational realm. It is argued that a diagrammatic logic needs to be expanded in multiple ways in order to attain a comprehensive logic of icons.