Dedekind, (Julius Wilhelm) Richard (1831–1916)

Richard Dedekind

Richard Dedekind was a German mathematician whose most important contribution was the discovery of what became known as the Dedekind cut. He realized that every real number r divides the rational numbers into two subsets: those greater than r and those less than r. Dedekind's brilliant idea was to represent the real numbers by such divisions of the rationals. He also provided important support for Georg Cantor's set theory, which was highly controversial at the time.