Logician Extraordinaire

Stanislaw Lesniewski (1886--1939) received his Ph.D. at Lwow University under the direction of Kazimierz Twardowski in 1912. After a few years of teaching in schools for girls he left for Poland and soon joined the codebreaking group that helped Poland win the battle of the Vistual. In 1919 he became Extraordinary Professor of the Foundations of Mathematics at Warsaw University, a position created especially for him. His obsession with the Russell Antinomy led him to create three foundational system for mathematics:  Protothetic, Ontology, and Mereology. His concern for rigor led him to formulate the rules of procedure in a precise way that was unmatched.  We will discuss the basic ideas of his systems and their fate.