In "The Fundamental Crisis of Mathematics," contradictions in the foundations of this science are demonstrated. This includes the mathematics of the infinite, created by Georg Cantor (1845-1918). It was originally highly emotional and controversially debated in an unscientific manner. Hilbert saw himself in a paradise from which he could not be expelled, while Poincaré diagnosed a disease from which mathematics would recover. However, contradictions were not proven, although the author points them out. In the axiomatic justification of Cantor's theory that followed, zero was incorrectly defined. The correction also necessitates a fundamental revision of the mathematics of the infinite. In contrast, Kurt Gödel's (1906-1978) incompleteness theorems, which assert the existence of mathematical statements for which neither proof nor disproof is possible, have so far been undisputed.