Diagrammatic relations of probative strength and inferential progression through semiotics.

Abstract

The purpose of this article is to explore the concept of diagram and diagrammatic reasoning involving semiotics in its three branches and not only

in speculative grammar. We will concentrate on the apprehension of the move- ment of reasoning, which diagrammatically begins with speculative grammar,

runs through critical logic, and consolidates at methodeutics. We seek to apply the trichotomic logic of Peirce to list the modes of reasoning with diagrams. Our intention is to move away from the categorization as taxonomy, and try to understand how sign classes can be used in the inferential process. Thus, considering a possible relationship between the hypoicon, the three classes of iconic signs in the system of ten classes of signs, and the methods of inference, we suggest three subclasses of diagrams in inferential terms that may offer a grading system, which would present degrees of accuracy or probative capacity.