Logical Analysis of Triadic Propositions

Abstract

The present article intends to show a reasonable and documentary analysis of two important logical classifications: classification of quantified proposition into factual and external and classification of positive predicative proposition into factual, external and mental. The overlap of these two classifications which was happened because of the participation of the term, created many problems and ambiguities in understanding of the predecessors’ knowledge of sciences. The present article is an attempt to study these two classifications with a logical and epistemological approach. Our attitude in this article is a historical one. We first, analyze the bipartite classification then explain two reports of the triadic classification. In the shade of logical analysis and historical explanation the weaknesses and strengths of these classifications would become clear. Also we survey the opposing viewpoint in this problem.