The 'method of superposition' in Euclid

Abstract

The ‘method of superposition’ is described through the singular use of the diagram, but it is appropriate to study the latter in the context of visual-linguistic cooperation, that is, in the framework of inferentially relevant expressive heterogeneity, characteristic of Euclidean proof. The purpose of this paper is then to examine the ‘method of superposition’ in detail, in particular, its argumentative strategy, doing justice to such heterogeneous modality. This examination identifies two salient features: a) an original inferential use of the diagram (systematically counterbalanced by the linguistic contribution), and b) a precise awareness of the deductive limits of such an association.