Abstract

One of the important discussions in predicative logic which is very close to the discussions in the logic of propositions is the problem of logical relations between propositions. This problem was often referred to under the title "contradiction and conversion" or "the principles of proposition" in early logical books, and today it is studied under the title "representative reasoning". These relations were gradually indentified in the course of the history of logic and assumed particular names. However, the correctness of some of them has been questioned by a group of logicians.In this paper, by reference to the number of logical relations and two ways of classifying them, the writer investigates whether logicians have referred to all possible logical relations, and whether all the existing ones have been identified based on rational reasoning or through induction. Finally, he tries to demonstrate how many definite relations exist between propositions consisting of two definite terms , and which of them is more fundamental