Abraham Fraenkel

Abraham Fraenkel was born in 1891 in Munich

Fraenkel was born on February 17, 1891, in Munich to a Neo-Orthodox family. His father, Avi'ezri Fraenkel, was a commercial adviser and later a founder of Agudat Yisrael. He studied at the universities of Munich, Marburg, Berlin and Breslau, and earned a doctorate in mathematics from Marburg in 1914 under Kurt Hensel.

He fought in the German army throughout World War I. He then taught at Marburg and became a professor there in 1922. In 1928 he moved to Kiel University and was also appointed professor at the Hebrew University of Jerusalem.

After losing his job in Germany, he settled permanently in the Land of Israel in 1933 and changed his first name from Adolf to Abraham. He was the first dean of the faculty of mathematics and natural sciences and served as rector from 1938 to 1940. His work on set theory added the axiom of replacement to Zermelo's system, giving the Zermelo-Fraenkel axioms.

He was a Zionist active in the Mizrachi movement and a member of the Jewish National Council and the Assembly of Representatives. He edited the mathematics section of the Hebrew Encyclopedia and wrote a 5-volume introduction to mathematics in Hebrew. He retired from the Hebrew University in 1959, then taught at Bar-Ilan University, and died in Jerusalem on October 15, 1965.