Template:Are You Sure/May 12

• ... that mathematician, philosopher, and logician Stanisław Leśniewski (1886–1939) proposed a logical model comprising three nested formal systems, to which he gave the Greek-derived names of protothetic, ontology, and mereology; and that Leśniewski's writings had limited impact because of their enigmatic style and highly idiosyncratic notation; and that even thought Alfred Tarski was his sole doctoral pupil, Leśniewski nevertheless strongly influenced an entire generation of Polish logicians and mathematicians via his teaching at the University of Warsaw?