1845-1918

German Mathematician

Georg Cantor is regarded as the founder of set theory. He also introduced the concept of transfinite numbers. This is the idea that there is not just one quantity of "infinity," but many quantities that are distinct from one another but all indefinitely large.

Cantor was born in St. Petersburg, Russia, on March 3, 1845. His father was a well-to-do merchant, and his mother was an artistic woman from a family of musicians. In 1856, the family moved to Germany. Cantor's mathematical talents soon became apparent at gymnasien, or secondary schools, in Darmstadt and Wiesbaden.

As an undergraduate student at the University of Berlin, Cantor specialized in mathematics, physics, and philosophy. There, he first met the mathematician Leopold Kronecker (1823-1891), who was later to become his archrival. In 1867, Cantor received his doctorate from the University of Göttingen, with a...