ABSTRACT
How has the historical boundary developed between logic and set theory? Prior to Georg Cantor’s researches, the notion of class belonged to logic and hence constituted a part of philosophy. In particular George Boole, whose logic continued to be influenced by the Aristotelian tradition, employed the notion of class in this fashion . 1 Yet during the 1880s, when Cantor generalized his funda mental notion from that of a point-set (a set of ^ -tuples of real numbers) to that of a set with elements of arbitrary nature, the time was ripe for an interplay between set theory as a part of mathematics and logic as a part of philosophy .2
